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Sample records for acid-soluble spore proteins

  1. Properties of spores of Bacillus subtilis strains which lack the major small, acid-soluble protein

    International Nuclear Information System (INIS)

    Hackett, R.H.; Setlow, P.

    1988-01-01

    Bacillus subtilis strains containing a deletion in the gene coding for the major small, acid-soluble, spore protein (SASP-gamma) grew and sporulated, and their spores initiated germination normally, but outgrowth of SASP-gamma- spores was significantly slower than that of wild-type spores. The absence of SASP-gamma had no effect on spore protoplast density or spore resistance to heat or radiation. Consequently, SASP-gamma has a different function in spores than do the other major small, acid-soluble proteins

  2. Small acid soluble proteins for rapid spore identification.

    Energy Technology Data Exchange (ETDEWEB)

    Branda, Steven S.; Lane, Todd W.; VanderNoot, Victoria A.; Jokerst, Amanda S.

    2006-12-01

    This one year LDRD addressed the problem of rapid characterization of bacterial spores such as those from the genus Bacillus, the group that contains pathogenic spores such as B. anthracis. In this effort we addressed the feasibility of using a proteomics based approach to spore characterization using a subset of conserved spore proteins known as the small acid soluble proteins or SASPs. We proposed developing techniques that built on our previous expertise in microseparations to rapidly characterize or identify spores. An alternative SASP extraction method was developed that was amenable to both the subsequent fluorescent labeling required for laser-induced fluorescence detection and the low ionic strength requirements for isoelectric focusing. For the microseparations, both capillary isoelectric focusing and chip gel electrophoresis were employed. A variety of methods were evaluated to improve the molecular weight resolution for the SASPs, which are in a molecular weight range that is not well resolved by the current methods. Isoelectric focusing was optimized and employed to resolve the SASPs using UV absorbance detection. Proteomic signatures of native wild type Bacillus spores and clones genetically engineered to produce altered SASP patterns were assessed by slab gel electrophoresis, capillary isoelectric focusing with absorbance detection as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection.

  3. Synthesis of acid-soluble spore proteins by Bacillus subtilis.

    OpenAIRE

    Leventhal, J M; Chambliss, G H

    1982-01-01

    The major acid-soluble spore proteins (ASSPs) of Bacillus subtilis were detected by immunoprecipitation of radioactively labeled in vitro- and in vivo-synthesized proteins. ASSP synthesis in vivo began 2 h after the initiation of sporulation (t2) and reached its maximum rate at t7. This corresponded to the time of synthesis of mRNA that stimulated the maximum rate of ASSP synthesis in vitro. Under the set of conditions used in these experiments, protease synthesis began near t0, alkaline phos...

  4. Decreased UV light resistance of spores of Bacillus subtilis strains deficient in pyrimidine dimer repair and small, acid-soluble spore proteins

    International Nuclear Information System (INIS)

    Setlow, B.; Setlow, P.

    1988-01-01

    Loss of small, acid-soluble spore protein alpha reduced spore UV resistance 30- to 50-fold in Bacillus subtilis strains deficient in pyrimidine dimer repair, but gave only a 5- to 8-fold reduction in UV resistance in repair-proficient strains. However, both repair-proficient and -deficient spores lacking this protein had identical heat and gamma-radiation resistance

  5. Synthesis of acid-soluble spore proteins by Bacillus subtilis.

    Science.gov (United States)

    Leventhal, J M; Chambliss, G H

    1982-12-01

    The major acid-soluble spore proteins (ASSPs) of Bacillus subtilis were detected by immunoprecipitation of radioactively labeled in vitro- and in vivo-synthesized proteins. ASSP synthesis in vivo began 2 h after the initiation of sporulation (t2) and reached its maximum rate at t7. This corresponded to the time of synthesis of mRNA that stimulated the maximum rate of ASSP synthesis in vitro. Under the set of conditions used in these experiments, protease synthesis began near t0, alkaline phosphatase synthesis began at about t2, and refractile spores were first observed between t7 and t8. In vivo- and in vitro-synthesized ASSPs comigrated in sodium dodecyl sulfate-polyacrylamide gels. Their molecular weights were 4,600 (alpha and beta) and 11,000 (gamma). The average half-life of the ASSP messages was 11 min when either rifampin (10 micrograms/ml) or actinomycin D (1 microgram/ml) was used to inhibit RNA synthesis.

  6. Absence of transient elevated uv resistance during germination of Bacillus subtilis spores lacking small, acid-soluble spore proteins α and β

    International Nuclear Information System (INIS)

    Setlow, B.; Setlow, P.

    1988-01-01

    Dormant spores of various Bacillus species are much more resistant to UV irradiation than are the corresponding vegetative cells. This elevated spore UV resistance appears to have two causes. First, UV irradiation of spores does not produce the pyrimidine dimers formed in vegetative-cell DNA, but rather produces several other photoproducts, the most predominant of which is termed the spore photoproduct, a 5-thyminyl-5,6-dihydrothymine adduct (1, 10). Second, spores have at least two mechanisms which efficiently repair this spore photoproduct during spore germination, including one which monomerizes the adduct back to two thymines. This study shows that germinating spores of bacillus subtilis mutants which lack small, acid-soluble spore proteins α and β did not exhibit the transient elevated UV resistance seen during germination of wild-type spores

  7. Synthesis of a Bacillus subtilis small, acid-soluble spore protein in Escherichia coli causes cell DNA to assume some characteristics of spore DNA

    International Nuclear Information System (INIS)

    Setlow, B.; Hand, A.R.; Setlow, P.

    1991-01-01

    Small, acid-soluble proteins (SASP) of the alpha/beta-type are associated with DNA in spores of Bacillus subtilis. Induction of synthesis of alpha/beta-type SASP in Escherichia coli resulted in rapid cessation of DNA synthesis, followed by a halt in RNA and then protein accumulation, although significant mRNA and protein synthesis continued. There was a significant loss in viability associated with SASP synthesis in E. coli: recA+ cells became extremely long filaments, whereas recA mutant cells became less filamentous. The nucleoids of cells with alpha/beta-type SASP were extremely condensed, as viewed in both light and electron microscopes, and immunoelectron microscopy showed that the alpha/beta-type SASP were associated with the cell DNA. Induction of alpha/beta-type SASP synthesis in E. coli increased the negative superhelical density of plasmid DNA by approximately 20%; UV irradiation of E. coli with alpha/beta-type SASP gave reduced yields of thymine dimers but significant amounts of the spore photoproduct. These changes in E. coli DNA topology and photochemistry due to alpha/beta-type SASP are similar to the effects of alpha/beta-type SASP on the DNA in Bacillus spores, further suggesting that alpha/beta-type SASP are a major factor determining DNA properties in bacterial spores

  8. Different small, acid-soluble proteins of the alpha/beta type have interchangeable roles in the heat and UV radiation resistance of Bacillus subtilis spores

    International Nuclear Information System (INIS)

    Mason, J.M.; Setlow, P.

    1987-01-01

    Spores of Bacillus subtilis strains which carry deletion mutations in one gene (sspA) or two genes (sspA and sspB) which code for major alpha/beta-type small, acid-soluble spore proteins (SASP) are known to be much more sensitive to heat and UV radiation than wild-type spores. This heat- and UV-sensitive phenotype was cured completely or in part by introduction into these mutant strains of one or more copies of the sspA or sspB genes themselves; multiple copies of the B. subtilis sspD gene, which codes for a minor alpha/beta-type SASP; or multiple copies of the SASP-C gene, which codes for a major alpha/beta-type SASP of Bacillus megaterium. These findings suggest that alpha/beta-type SASP play interchangeable roles in the heat and UV radiation resistance of bacterial spores

  9. 14C Analysis of protein extracts from Bacillus spores.

    Science.gov (United States)

    Cappuccio, Jenny A; Falso, Miranda J Sarachine; Kashgarian, Michaele; Buchholz, Bruce A

    2014-07-01

    Investigators of bioagent incidents or interdicted materials need validated, independent analytical methods that will allow them to distinguish between recently made bioagent samples versus material drawn from the archives of a historical program. Heterotrophic bacteria convert the carbon in their food sources, growth substrate or culture media, into the biomolecules they need. The F(14)C (fraction modern radiocarbon) of a variety of media, Bacillus spores, and separated proteins from Bacillus spores was measured by accelerator mass spectrometry (AMS). AMS precisely measures F(14)C values of biological materials and has been used to date the synthesis of biomaterials over the bomb pulse era (1955 to present). The F(14)C of Bacillus spores reflects the radiocarbon content of the media in which they were grown. In a survey of commercial media we found that the F(14)C value indicated that carbon sources for the media were alive within about a year of the date of manufacture and generally of terrestrial origin. Hence, bacteria and their products can be dated using their (14)C signature. Bacillus spore samples were generated onsite with defined media and carbon free purification and also obtained from archived material. Using mechanical lysis and a variety of washes with carbon free acids and bases, contaminant carbon was removed from soluble proteins to enable accurate (14)C bomb-pulse dating. Since media is contemporary, (14)C bomb-pulse dating of isolated soluble proteins can be used to distinguish between historical archives of bioagents and those produced from recent media. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. A Soluble, Folded Protein without Charged Amino Acid Residues

    DEFF Research Database (Denmark)

    Højgaard, Casper; Kofoed, Christian; Espersen, Roall

    2016-01-01

    Charges are considered an integral part of protein structure and function, enhancing solubility and providing specificity in molecular interactions. We wished to investigate whether charged amino acids are indeed required for protein biogenesis and whether a protein completely free of titratable...... side chains can maintain solubility, stability, and function. As a model, we used a cellulose-binding domain from Cellulomonas fimi, which, among proteins of more than 100 amino acids, presently is the least charged in the Protein Data Bank, with a total of only four titratable residues. We find...

  11. Effects of steam autoclave treatment on Geobacillus stearothermophilus spores.

    Science.gov (United States)

    Huesca-Espitia, L C; Suvira, M; Rosenbeck, K; Korza, G; Setlow, B; Li, W; Wang, S; Li, Y-Q; Setlow, P

    2016-11-01

    To determine the mechanism of autoclave killing of Geobacillus stearothermophilus spores used in biological indicators (BIs) for steam autoclave sterilization, and rates of loss of spore viability and a spore enzyme used in BIs. Spore viability, dipicolinic acid (DPA) release, nucleic acid staining, α-glucosidase activity, protein structure and mutagenesis were measured during autoclaving of G. stearothermophilus spores. Loss of DPA and increases in spore core nucleic acid staining were slower than loss of spore viability. Spore core α-glucosidase was also lost more slowly than spore viability, although soluble α-glucosidase in spore preparations was lost more rapidly. However, spores exposed to an effective autoclave sterilization lost all viability and α-glucosidase activity. Apparently killed autoclaved spores were not recovered by artificial germination in supportive media, much spore protein was denatured during autoclaving, and partially killed autoclave-treated spore preparations did not acquire mutations. These results indicate that autoclave-killed spores cannot be revived, spore killing by autoclaving is likely by protein damage, and spore core α-glucosidase activity is lost more slowly than spore viability. This work provides insight into the mechanism of autoclave killing of spores of an organism used in BIs, and that a spore enzyme in a BI is more stable to autoclaving than spore viability. © 2016 The Society for Applied Microbiology.

  12. The Influence of Sporulation Conditions on the Spore Coat Protein Composition of Bacillus subtilis Spores.

    Science.gov (United States)

    Abhyankar, Wishwas R; Kamphorst, Kiki; Swarge, Bhagyashree N; van Veen, Henk; van der Wel, Nicole N; Brul, Stanley; de Koster, Chris G; de Koning, Leo J

    2016-01-01

    Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has also been shown that the more mature a spore is, the higher is its heat resistance most likely mediated, at least in part, by the progressive cross-linking of coat proteins. The current study for the first time assesses, at the proteomic level, the effect of two commonly used sporulation conditions on spore protein presence. 14 N spores prepared on solid Schaeffer's-glucose (SG) agar plates and 15 N metabolically labeled spores prepared in shake flasks containing 3-( N -morpholino) propane sulfonic acid (MOPS) buffered defined liquid medium differ in their coat protein composition as revealed by LC-FT-MS/MS analyses. The former condition mimics the industrial settings while the latter conditions mimic the routine laboratory environment wherein spores are developed. As seen previously in many studies, the spores prepared on the solid agar plates show a higher thermal resistance than the spores prepared under liquid culture conditions. The 14 N: 15 N isotopic ratio of the 1:1 mixture of the spore suspensions exposes that most of the identified inner coat and crust proteins are significantly more abundant while most of the outer coat proteins are significantly less abundant for the spores prepared on solid SG agar plates relative to the spores prepared in the liquid MOPS buffered defined medium. Sporulation condition-specific differences and variation in isotopic ratios between the tryptic peptides of expected cross-linked proteins suggest that the coat protein cross-linking may also be condition specific. Since the core dipicolinic acid content is found to be similar in both the spore populations, it appears that the difference in wet heat resistance is connected to the

  13. The Influence of Sporulation Conditions on the Spore Coat Protein Composition of Bacillus subtilis Spores

    Science.gov (United States)

    Abhyankar, Wishwas R.; Kamphorst, Kiki; Swarge, Bhagyashree N.; van Veen, Henk; van der Wel, Nicole N.; Brul, Stanley; de Koster, Chris G.; de Koning, Leo J.

    2016-01-01

    Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has also been shown that the more mature a spore is, the higher is its heat resistance most likely mediated, at least in part, by the progressive cross-linking of coat proteins. The current study for the first time assesses, at the proteomic level, the effect of two commonly used sporulation conditions on spore protein presence. 14N spores prepared on solid Schaeffer’s-glucose (SG) agar plates and 15N metabolically labeled spores prepared in shake flasks containing 3-(N-morpholino) propane sulfonic acid (MOPS) buffered defined liquid medium differ in their coat protein composition as revealed by LC-FT-MS/MS analyses. The former condition mimics the industrial settings while the latter conditions mimic the routine laboratory environment wherein spores are developed. As seen previously in many studies, the spores prepared on the solid agar plates show a higher thermal resistance than the spores prepared under liquid culture conditions. The 14N:15N isotopic ratio of the 1:1 mixture of the spore suspensions exposes that most of the identified inner coat and crust proteins are significantly more abundant while most of the outer coat proteins are significantly less abundant for the spores prepared on solid SG agar plates relative to the spores prepared in the liquid MOPS buffered defined medium. Sporulation condition-specific differences and variation in isotopic ratios between the tryptic peptides of expected cross-linked proteins suggest that the coat protein cross-linking may also be condition specific. Since the core dipicolinic acid content is found to be similar in both the spore populations, it appears that the difference in wet heat resistance is connected to the

  14. Spore coat protein of Bacillus subtilis. Structure and precursor synthesis.

    Science.gov (United States)

    Munoz, L; Sadaie, Y; Doi, R H

    1978-10-10

    The coat protein of Bacillus subtilis spores comprises about 10% of the total dry weight of spores and 25% of the total spore protein. One protein with a molecular weight of 13,000 to 15,000 comprises a major portion of the spore coat. This mature spore coat protein has histidine at its NH2 terminus and is relatively rich in hydrophobic amino acids. Netropsin, and antibiotic which binds to A-T-rich regions of DNA and inhibits sporulation, but not growth, decreased the synthesis of this spore coat protein by 75%. A precursor spore coat protein with a molecular weight of 25,000 is made initially at t1 of sporulation and is converted to the mature spore coat protein with a molecular weight of 13,500 at t2 - t3. These data indicate that the spore coat protein gene is expressed very early in sporulation prior to the modifications of RNA polymerase which have been noted.

  15. A Soluble, Folded Protein without Charged Amino Acid Residues

    DEFF Research Database (Denmark)

    Højgaard, Casper; Kofoed, Christian; Espersen, Roall

    2016-01-01

    side chains can maintain solubility, stability, and function. As a model, we used a cellulose-binding domain from Cellulomonas fimi, which, among proteins of more than 100 amino acids, presently is the least charged in the Protein Data Bank, with a total of only four titratable residues. We find......Charges are considered an integral part of protein structure and function, enhancing solubility and providing specificity in molecular interactions. We wished to investigate whether charged amino acids are indeed required for protein biogenesis and whether a protein completely free of titratable...... that the protein shows a surprising resilience toward extremes of pH, demonstrating stability and function (cellulose binding) in the pH range from 2 to 11. To ask whether the four charged residues present were required for these properties of this protein, we altered them to nontitratable ones. Remarkably...

  16. The influence of sporulation conditions on the spore coat protein composition of Bacillus subtilis spores.

    Directory of Open Access Journals (Sweden)

    Wishwas R. Abhyankar

    2016-10-01

    Full Text Available Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has also been shown that the more mature a spore is, the higher is its heat resistance most likely mediated, at least in part, by the progressive cross-linking of coat proteins. The current study for the first time assesses, at the proteomic level, the effect of two commonly used sporulation conditions on spore protein presence. 14N spores prepared on solid SG agar plates and 15N metabolically labelled spores prepared in shake flasks containing MOPS buffered defined liquid medium differ in their coat protein composition as revealed by LC-FT-MS/MS analyses. The former condition mimics the industrial settings while the latter conditions mimic the routine laboratory environment wherein spores are developed. As seen previously in many studies, the spores prepared on the solid agar plates show a higher thermal resistance than the spores prepared under liquid culture conditions. The 14N: 15N isotopic ratio of the 1:1 mixture of the spore suspensions exposes that most of the identified inner coat and crust proteins are significantly more abundant while most of the outer coat proteins are significantly less abundant for the spores prepared on solid SG agar plates relative to the spores prepared in the liquid MOPS buffered defined medium. Sporulation condition-specific differences and variation in isotopic ratios between the tryptic peptides of expected cross-linked proteins suggest that the coat protein cross-linking may also be condition specific. Since the core dipicolinic acid content is found to be similar in both the spore populations, it appears that the difference in wet heat resistance is connected to the differences in the coat protein composition and

  17. The regulated synthesis of a Bacillus anthracis spore coat protein that affects spore surface properties.

    Science.gov (United States)

    Aronson, A; Goodman, B; Smith, Z

    2014-05-01

    Examine the regulation of a spore coat protein and the effects on spore properties. A c. 23 kDa band in coat/exosporial extracts of Bacillus anthracis Sterne spores varied in amount depending upon the conditions of sporulation. It was identified by MALDI as a likely orthologue of ExsB of Bacillus cereus. Little if any was present in an exosporial preparation with a location to the inner coat/cortex region established by spore fractionation and immunogold labelling of electron micrograph sections. Because of its predominant location in the inner coat, it has been renamed Cotγ. It was relatively deficient in spores produced at 37°C and when acidic fermentation products were produced a difference attributable to transcriptional regulation. The deficiency or absence of Cotγ resulted in a less robust exosporium positioned more closely to the coat. These spores were less hydrophobic and germinated somewhat more rapidly. Hydrophobicity and appearance were rescued in the deletion strain by introduction of the cotγ gene. The deficiency or lack of a protein largely found in the inner coat altered spore hydrophobicity and surface appearance. The regulated synthesis of Cotγ may be a paradigm for other spore coat proteins with unknown functions that modulate spore properties in response to environmental conditions. © 2014 The Society for Applied Microbiology.

  18. Mechanism of Bacillus subtilis spore inactivation by and resistance to supercritical CO2 plus peracetic acid.

    Science.gov (United States)

    Setlow, B; Korza, G; Blatt, K M S; Fey, J P; Setlow, P

    2016-01-01

    Determine how supercritical CO2 (scCO2 ) plus peracetic acid (PAA) inactivates Bacillus subtilis spores, factors important in spore resistance to scCO2 -PAA, and if spores inactivated by scCO2 -PAA are truly dead. Spores of wild-type B. subtilis and isogenic mutants lacking spore protective proteins were treated with scCO2 -PAA in liquid or dry at 35°C. Wild-type wet spores (aqueous suspension) were more susceptible than dry spores. Treated spores were examined for viability (and were truly dead), dipicolinic acid (DPA), mutations, permeability to nucleic acid stains, germination under different conditions, energy metabolism and outgrowth. ScCO2 -PAA-inactivated spores retained DPA, and survivors had no notable DNA damage. However, DPA was released from inactivated spores at a normally innocuous temperature (85°C), and colony formation from treated spores was salt sensitive. The inactivated spores germinated but did not outgrow, and these germinated spores had altered plasma membrane permeability and defective energy metabolism. Wet or dry coat-defective spores had increased scCO2 -PAA sensitivity, and dry spores but not wet spores lacking DNA protective proteins were more scCO2 -PAA sensitive. These findings suggest that scCO2 -PAA inactivates spores by damaging spores' inner membrane. The spore coat provided scCO2 -PAA resistance for both wet and dry spores. DNA protective proteins provided scCO2 -PAA resistance only for dry spores. These results provide information on mechanisms of spore inactivation of and resistance to scCO2 -PAA, an agent with increasing use in sterilization applications. © 2015 The Society for Applied Microbiology.

  19. Use of yeast spores for microencapsulation of enzymes.

    Science.gov (United States)

    Shi, Libing; Li, Zijie; Tachikawa, Hiroyuki; Gao, Xiao-Dong; Nakanishi, Hideki

    2014-08-01

    Here, we report a novel method to produce microencapsulated enzymes using Saccharomyces cerevisiae spores. In sporulating cells, soluble secreted proteins are transported to the spore wall. Previous work has shown that the spore wall is capable of retaining soluble proteins because its outer layers work as a diffusion barrier. Accordingly, a red fluorescent protein (RFP) fusion of the α-galactosidase, Mel1, expressed in spores was observed in the spore wall even after spores were subjected to a high-salt wash in the presence of detergent. In vegetative cells, however, the cell wall cannot retain the RFP fusion. Although the spore wall prevents diffusion of proteins, it is likely that smaller molecules, such as sugars, pass through it. In fact, spores can contain much higher α-galactosidase activity to digest melibiose than vegetative cells. When present in the spore wall, the enzyme acquires resistance to environmental stresses including enzymatic digestion and high temperatures. The outer layers of the spore wall are required to retain enzymes but also decrease accessibility of the substrates. However, mutants with mild spore wall defects can retain and stabilize the enzyme while still permitting access to the substrate. In addition to Mel1, we also show that spores can retain the invertase. Interestingly the encapsulated invertase has significantly lower activity toward raffinose than toward sucrose.This suggests that substrate selectivity could be altered by the encapsulation.

  20. PON-Sol: prediction of effects of amino acid substitutions on protein solubility.

    Science.gov (United States)

    Yang, Yang; Niroula, Abhishek; Shen, Bairong; Vihinen, Mauno

    2016-07-01

    Solubility is one of the fundamental protein properties. It is of great interest because of its relevance to protein expression. Reduced solubility and protein aggregation are also associated with many diseases. We collected from literature the largest experimentally verified solubility affecting amino acid substitution (AAS) dataset and used it to train a predictor called PON-Sol. The predictor can distinguish both solubility decreasing and increasing variants from those not affecting solubility. PON-Sol has normalized correct prediction ratio of 0.491 on cross-validation and 0.432 for independent test set. The performance of the method was compared both to solubility and aggregation predictors and found to be superior. PON-Sol can be used for the prediction of effects of disease-related substitutions, effects on heterologous recombinant protein expression and enhanced crystallizability. One application is to investigate effects of all possible AASs in a protein to aid protein engineering. PON-Sol is freely available at http://structure.bmc.lu.se/PON-Sol The training and test data are available at http://structure.bmc.lu.se/VariBench/ponsol.php mauno.vihinen@med.lu.se Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. The Conserved Spore Coat Protein SpoVM Is Largely Dispensable in Clostridium difficile Spore Formation.

    Science.gov (United States)

    Ribis, John W; Ravichandran, Priyanka; Putnam, Emily E; Pishdadian, Keyan; Shen, Aimee

    2017-01-01

    The spore-forming bacterial pathogen Clostridium difficile is a leading cause of health care-associated infections in the United States. In order for this obligate anaerobe to transmit infection, it must form metabolically dormant spores prior to exiting the host. A key step during this process is the assembly of a protective, multilayered proteinaceous coat around the spore. Coat assembly depends on coat morphogenetic proteins recruiting distinct subsets of coat proteins to the developing spore. While 10 coat morphogenetic proteins have been identified in Bacillus subtilis , only two of these morphogenetic proteins have homologs in the Clostridia : SpoIVA and SpoVM. C. difficile SpoIVA is critical for proper coat assembly and functional spore formation, but the requirement for SpoVM during this process was unknown. Here, we show that SpoVM is largely dispensable for C. difficile spore formation, in contrast with B. subtilis . Loss of C. difficile SpoVM resulted in modest decreases (~3-fold) in heat- and chloroform-resistant spore formation, while morphological defects such as coat detachment from the forespore and abnormal cortex thickness were observed in ~30% of spoVM mutant cells. Biochemical analyses revealed that C. difficile SpoIVA and SpoVM directly interact, similarly to their B. subtilis counterparts. However, in contrast with B. subtilis , C. difficile SpoVM was not essential for SpoIVA to encase the forespore. Since C. difficile coat morphogenesis requires SpoIVA-interacting protein L (SipL), which is conserved exclusively in the Clostridia , but not the more broadly conserved SpoVM, our results reveal another key difference between C. difficile and B. subtilis spore assembly pathways. IMPORTANCE The spore-forming obligate anaerobe Clostridium difficile is the leading cause of antibiotic-associated diarrheal disease in the United States. When C. difficile spores are ingested by susceptible individuals, they germinate within the gut and

  2. Heat, hydrogen peroxide, and UV resistance of Bacillus subtilis spores with increased core water content and with or without major DNA-binding proteins

    International Nuclear Information System (INIS)

    Popham, D.L.; Sengupta, S.; Setlow, P.

    1995-01-01

    Spores of a Bacillus subtilis strain with an insertion mutation in the dacB gene, which codes for an enzyme involved in spore cortex biosynthesis, have a higher core water content than wild-type spores. Spores lacking the two major α/β-type small, acid-soluble proteins (SASP) (termed a α - β - spores) have the same core water content as do wild-type spores, but α - β - dacB spores had more core water than did dacB spores. The resistance of α - β - , α - β - dacB, dacB, and wild-type spores to dry and moist heat, hydrogen peroxide, and UV radiation has been determined, as has the role of DNA damage in spore killing by moist heat and hydrogen peroxide. These data (1) suggest that core water content has little if any role in spore UV resistance and are consistent with binding of α/β-type SASP to DNA being the major mechanism providing protection to spores from UV radiation; (2) suggest that binding of αβ-type SASP to DNA is the major mechanism unique to spores providing protection from dry heat; (3) suggest that spore resistance to moist heat and hydrogen peroxide is affected to a large degree by the core water content, as increased core water resulted in large decreases in spore resistance to these agents; and (4) indicate that since this decreased resistance (i.e., in dacB spores) is not associated with increased spore killing by DNA damage, spore DNA must normally be extremely well protected against such damage, presumably by the saturation of spore DNA by α/β-type SASP. 19 refs., 2 figs., 5 tabs

  3. Spore membrane(s) as the site of damage within heated Clostridium perfringens spores.

    Science.gov (United States)

    Flowers, R S; Adams, D M

    1976-02-01

    Clostridium perfringens spores were injured by ultrahigh-temperature treatment at 105 C for 5 min. Injury was manifested as an increased sensitivity to polymyxin and neomycin. Since many of the survivors could not germinate normally the ultrahigh-temperature-treated spores were sensitized to and germinated by lysozyme. Polymyxin reportedly acts upon the cell membrane. Neomycin may inhibit protein synthesis and has surface-active properties. Injured spores were increasingly sensitive to known surface-active agents, sodium lauryl sulfate, sodium deoxycholate, and Roccal, a quaternary ammonium compound. Injured spores sensitive to polymyxin and neomycin also were osmotically fragile and died during outgrowth in a liquid medium unless the medium was supplemented with 20% sucrose, 10% dextran, or 10% polyvinylpyrrolidone. The results suggested that a spore structure destined to become cell membrane or cell wall was the site of injury. Repair of injury during outgrowth in the presence of protein, deoxyribonucleic acid, ribonucleic acid and cell wall synthesis inhibitors was consistent with this hypothesis.

  4. Detection of spore coat protein of Bacillus subtilis by immunological method

    International Nuclear Information System (INIS)

    Uchida, Aritsune; Kadota, Hajime

    1976-01-01

    The spore coat protein of Bacillus subtilis was separated, and the qualitative assay for the spore coat protein was made by use of the immunological technique. The immunological method was found to be useful for judging the maturation of spore coat in the course of sporulation. The spore coat protein antigen appeared at t 2 stage of sporulation. The addition of rifampicin at the earlier stages of sporulation inhibited the increase in content of the spore coat antigen. (auth.)

  5. Sialic Acid Binding Properties of Soluble Coronavirus Spike (S1 Proteins: Differences between Infectious Bronchitis Virus and Transmissible Gastroenteritis Virus

    Directory of Open Access Journals (Sweden)

    Christine Winter

    2013-07-01

    Full Text Available The spike proteins of a number of coronaviruses are able to bind to sialic acids present on the cell surface. The importance of this sialic acid binding ability during infection is, however, quite different. We compared the spike protein of transmissible gastroenteritis virus (TGEV and the spike protein of infectious bronchitis virus (IBV. Whereas sialic acid is the only receptor determinant known so far for IBV, TGEV requires interaction with its receptor aminopeptidase N to initiate infection of cells. Binding tests with soluble spike proteins carrying an IgG Fc-tag revealed pronounced differences between these two viral proteins. Binding of the IBV spike protein to host cells was in all experiments sialic acid dependent, whereas the soluble TGEV spike showed binding to APN but had no detectable sialic acid binding activity. Our results underline the different ways in which binding to sialoglycoconjugates is mediated by coronavirus spike proteins.

  6. Biomarkers of Aspergillus spores

    Science.gov (United States)

    Sulc, Miroslav; Peslova, Katerina; Zabka, Martin; Hajduch, Marian; Havlicek, Vladimir

    2009-02-01

    We applied both matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometric and 1D sodium dodecylsulfate polyacrylamide gel electrophoretic (1D-PAGE) approaches for direct analysis of intact fungal spores of twenty four Aspergillus species. In parallel, we optimized various protocols for protein extraction from Aspergillus spores using acidic conditions, step organic gradient and variable sonication treatment. The MALDI-TOF mass spectra obtained from optimally prepared samples provided a reproducible fingerprint demonstrating the capability of the MALDI-TOF approach to type and characterize different fungal strains within the Aspergillus genus. Mass spectra of intact fungal spores provided signals mostly below 20 kDa. The minimum material amount represented 0.3 [mu]g (10,000 spores). Proteins with higher molecular weight were detected by 1D-PAGEE Eleven proteins were identified from three selected strains in the range 5-25 kDa by the proteomic approach. Hemolysin and hydrophobin have the highest relevance in host-pathogen interactions.

  7. Protein Composition of Infectious Spores Reveals Novel Sexual Development and Germination Factors in Cryptococcus.

    Directory of Open Access Journals (Sweden)

    Mingwei Huang

    2015-08-01

    Full Text Available Spores are an essential cell type required for long-term survival across diverse organisms in the tree of life and are a hallmark of fungal reproduction, persistence, and dispersal. Among human fungal pathogens, spores are presumed infectious particles, but relatively little is known about this robust cell type. Here we used the meningitis-causing fungus Cryptococcus neoformans to determine the roles of spore-resident proteins in spore biology. Using highly sensitive nanoscale liquid chromatography/mass spectrometry, we compared the proteomes of spores and vegetative cells (yeast and identified eighteen proteins specifically enriched in spores. The genes encoding these proteins were deleted, and the resulting strains were evaluated for discernable phenotypes. We hypothesized that spore-enriched proteins would be preferentially involved in spore-specific processes such as dormancy, stress resistance, and germination. Surprisingly, however, the majority of the mutants harbored defects in sexual development, the process by which spores are formed. One mutant in the cohort was defective in the spore-specific process of germination, showing a delay specifically in the initiation of vegetative growth. Thus, by using this in-depth proteomics approach as a screening tool for cell type-specific proteins and combining it with molecular genetics, we successfully identified the first germination factor in C. neoformans. We also identified numerous proteins with previously unknown functions in both sexual development and spore composition. Our findings provide the first insights into the basic protein components of infectious spores and reveal unexpected molecular connections between infectious particle production and spore composition in a pathogenic eukaryote.

  8. Universal nucleic acids sample preparation method for cells, spores and their mixture

    Science.gov (United States)

    Bavykin, Sergei [Darien, IL

    2011-01-18

    The present invention relates to a method for extracting nucleic acids from biological samples. More specifically the invention relates to a universal method for extracting nucleic acids from unidentified biological samples. An advantage of the presently invented method is its ability to effectively and efficiently extract nucleic acids from a variety of different cell types including but not limited to prokaryotic or eukaryotic cells and/or recalcitrant organisms (i.e. spores). Unlike prior art methods which are focused on extracting nucleic acids from vegetative cell or spores, the present invention effectively extracts nucleic acids from spores, multiple cell types or mixtures thereof using a single method. Important that the invented method has demonstrated an ability to extract nucleic acids from spores and vegetative bacterial cells with similar levels effectiveness. The invented method employs a multi-step protocol which erodes the cell structure of the biological sample, isolates, labels, fragments nucleic acids and purifies labeled samples from the excess of dye.

  9. Muricholic acids inhibit Clostridium difficile spore germination and growth.

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    Michael B Francis

    Full Text Available Infections caused by Clostridium difficile have increased steadily over the past several years. While studies on C. difficile virulence and physiology have been hindered, in the past, by lack of genetic approaches and suitable animal models, newly developed technologies and animal models allow these processes to be studied in detail. One such advance is the generation of a mouse-model of C. difficile infection. The development of this system is a major step forward in analyzing the genetic requirements for colonization and infection. While important, it is equally as important in understanding what differences exist between mice and humans. One of these differences is the natural bile acid composition. Bile acid-mediated spore germination is an important step in C. difficile colonization. Mice produce several different bile acids that are not found in humans. These muricholic acids have the potential to impact C. difficile spore germination. Here we find that the three muricholic acids (α-muricholic acid, β-muricholic acid and ω-muricholic acid inhibit C. difficile spore germination and can impact the growth of vegetative cells. These results highlight an important difference between humans and mice and may have an impact on C. difficile virulence in the mouse-model of C. difficile infection.

  10. Reinforcement of Bacillus subtilis spores by cross-linking of outer coat proteins during maturation.

    Science.gov (United States)

    Abhyankar, Wishwas; Pandey, Rachna; Ter Beek, Alexander; Brul, Stanley; de Koning, Leo J; de Koster, Chris G

    2015-02-01

    Resistance characteristics of bacterial endospores towards various environmental stresses such as chemicals and heat are in part attributed to their coat proteins. Heat resistance is developed in a late stage of sporulation and during maturation of released spores. Using our gel-free proteomic approach and LC-FT-ICR-MS/MS analysis we have monitored the efficiency of the tryptic digestion of proteins in the coat during spore maturation over a period of eight days, using metabolically (15)N labeled mature spores as reference. The results showed that during spore maturation the loss of digestion efficiency of outer coat and crust proteins synchronized with the increase in heat resistance. This implicates that spore maturation involves chemical cross-linking of outer coat and crust layer proteins leaving the inner coat layer proteins unmodified. It appears that digestion efficiencies of spore surface proteins can be linked to their location within the coat and crust layers. We also attempted to study a possible link between spore maturation and the observed heterogeneity in spore germination. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. The influence of sporulation conditions on the spore coat protein composition of Bacillus subtilis spores.

    OpenAIRE

    Wishwas R. Abhyankar; Wishwas R. Abhyankar; Kiki Kamphorst; Bhagyashree N. Swarge; Bhagyashree N. Swarge; Henk van Veen; Nicole N. van der Wel; Stanley Brul; Chris G. de Koster; Leo J. de Koning

    2016-01-01

    Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has also been shown that the more mature a spore is, the higher is its heat resistance most likely mediated, at least in part, by the progressive cross-linking of coat proteins. The current study for t...

  12. The Influence of Sporulation Conditions on the Spore Coat Protein Composition of Bacillus subtilis Spores

    OpenAIRE

    Abhyankar, Wishwas R.; Kamphorst, Kiki; Swarge, Bhagyashree N.; van Veen, Henk; van der Wel, Nicole N.; Brul, Stanley; de Koster, Chris G.; de Koning, Leo J.

    2016-01-01

    Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has also been shown that the more mature a spore is, the higher is its heat resistance most likely mediated, at least in part, by the progressive cross-linking of coat proteins. The current study for t...

  13. [Studies on difference between sporoderm-broken and nonbroken spores of Ganoderma lucidum (Leyss. ex Fr.) Karst. by polysaccharide analysis].

    Science.gov (United States)

    Bao, X F; Fang, J N

    2001-05-01

    To compare the release ability of water-soluble polysaccharides in sporoderm-broken and nonbroken spores of Ganoderma lucidum, and establish a comparatively correct method for the determination and analysis of polysaccharide contents in Chinese herbs. The release ability of water-soluble polysaccharides was determined on the basis of phenol-sulfuric acid modification in different conditions. The release ability of polysaccharides of sporoderm-broken spores was much greater than that of nonbroken spores; and the phenol-sulfuric acid modified cation method proved excellent in accuracy and reproducibility, with a relative error less than 1.5%. The spores should be wall-wracked if used as a nutriment, or for extraction and analysis of their effective components. The method can be successfully used for the determination of polysaccharide contents in Chinese herbs or nutriments.

  14. Spore coat protein synthesis in cell-free systems from sporulating cells of Bacillus subtilis.

    Science.gov (United States)

    Nakayama, T; Munoz, L E; Sadaie, Y; Doi, R H

    1978-09-01

    Cell-free systems for protein synthesis were prepared from Bacillus subtilis 168 cells at several stages of sporulation. Immunological methods were used to determine whether spore coat protein could be synthesized in the cell-free systems prepared from sporulating cells. Spore coat protein synthesis first occurred in extracts from stage t2 cells. The proportion of spore coat protein to total proteins synthesized in the cell-free systems was 2.4 and 3.9% at stages t2 and t4, respectively. The sodium dodecyl sulfate-urea-polyacrylamide gel electrophoresis patterns of immunoprecipitates from the cell-free systems showed the complete synthesis of an apparent spore coat protein precursor (molecular weight, 25,000). A polypeptide of this weight was previously identified in studies in vivo (L.E. Munoz, Y. Sadaie, and R.H. Doi, J. Biol. Chem., in press). The synthesis in vitro of polysome-associated nascent spore coat polypeptides with varying molecular weights up to 23,000 was also detected. These results indicate that the spore coat protein may be synthesized as a precursor protein. The removal of proteases in the crude extracts by treatment with hemoglobin-Sepharose affinity techniques may be preventing the conversion of the large 25,000-dalton precursor to the 12,500-dalton mature spore coat protein.

  15. Modeling Thermal Inactivation of Bacillus Spores

    Science.gov (United States)

    2009-03-01

    information is preserved and replicated by the Watson - Crick base pairing in which 4-3 complementary bases recognize each other. One incorrect amino acid can...hydrolysis reactions to take place with the spore’s DNA and other proteins. These chemical reactions degrade the DNA and proteins to such an extent that the... DNA cannot be repaired or replicated, thus causing spore death. We further assert that damage to a spore is based on a certain initial DNA information

  16. Effect of enzymatic treatment of extracted sunflower proteins on solubility, amino acid composition, and surface activity.

    Science.gov (United States)

    Conde, José Miñones; Escobar, María del Mar Yust; Pedroche Jiménez, Justo J; Rodríguez, Francisco Millán; Rodríguez Patino, Juan M

    2005-10-05

    Industrial proteins from agriculture of either animal or vegetable origin, including their peptide derivatives, are of great importance, from the qualitative and quantitative point of view, in food formulations (emulsions and foams). A fundamental understanding of the physical, chemical, and functional properties of these proteins is essential if the performance of proteins in foods is to be improved and if underutilized proteins, such as plant proteins (and their hydrolysates and peptides derivatives), are to be increasingly used in traditional and new processed food products (safe, high-quality, health foods with good nutritional value). In this contribution we have determined the main physicochemical characteristics (solubility, composition, and analysis of amino acids) of a sunflower protein isolate (SPI) and its hydrolysates with low (5.62%), medium (23.5%), and high (46.3%) degrees of hydrolysis. The hydrolysates were obtained by enzymatic treatment with Alcalase 2.4 L for DH 5.62 and 23.5% and with Alcalase 2.4 L and Flavorzyme 1000 MG sequentially for DH 46.3%. The protein concentration dependence on surface pressure (surface pressure isotherm), a measure of the surface activity of the products (SPI and its hydrolysates), was obtained by tensiometry. We have observed that the degree of hydrolysis has an effect on solubility, composition, and content of the amino acids of the SPI and its hydrolysates. The superficial activity and the adsorption efficiency were also affected by the degree of hydrolysis.

  17. Production of soluble mammalian proteins in Escherichia coli: identification of protein features that correlate with successful expression

    Directory of Open Access Journals (Sweden)

    Perera Rajika L

    2004-12-01

    Full Text Available Abstract Background In the search for generic expression strategies for mammalian protein families several bacterial expression vectors were examined for their ability to promote high yields of soluble protein. Proteins studied included cell surface receptors (Ephrins and Eph receptors, CD44, kinases (EGFR-cytoplasmic domain, CDK2 and 4, proteases (MMP1, CASP2, signal transduction proteins (GRB2, RAF1, HRAS and transcription factors (GATA2, Fli1, Trp53, Mdm2, JUN, FOS, MAD, MAX. Over 400 experiments were performed where expression of 30 full-length proteins and protein domains were evaluated with 6 different N-terminal and 8 C-terminal fusion partners. Expression of an additional set of 95 mammalian proteins was also performed to test the conclusions of this study. Results Several protein features correlated with soluble protein expression yield including molecular weight and the number of contiguous hydrophobic residues and low complexity regions. There was no relationship between successful expression and protein pI, grand average of hydropathicity (GRAVY, or sub-cellular location. Only small globular cytoplasmic proteins with an average molecular weight of 23 kDa did not require a solubility enhancing tag for high level soluble expression. Thioredoxin (Trx and maltose binding protein (MBP were the best N-terminal protein fusions to promote soluble expression, but MBP was most effective as a C-terminal fusion. 63 of 95 mammalian proteins expressed at soluble levels of greater than 1 mg/l as N-terminal H10-MBP fusions and those that failed possessed, on average, a higher molecular weight and greater number of contiguous hydrophobic amino acids and low complexity regions. Conclusions By analysis of the protein features identified here, this study will help predict which mammalian proteins and domains can be successfully expressed in E. coli as soluble product and also which are best targeted for a eukaryotic expression system. In some cases

  18. Soluble protein isolated from low cost fish and fish wastes

    OpenAIRE

    Lekshmy Nair, A.; Gopakumar, K.

    1982-01-01

    The method of preparation, composition, amino acid content, protein efficiency ratio and areas of possible application of water soluble protein isolates from low cost fish and fish wastes are discussed in detail in this communication.

  19. Direct high-pressure NMR observation of dipicolinic acid leaking from bacterial spore: A crucial step for thermal inactivation.

    Science.gov (United States)

    Akasaka, Kazuyuki; Maeno, Akihiro; Yamazaki, Akira

    2017-12-01

    A bacterial spore protects itself with an unusually high concentration (~10% in dry weight of spore) of dipicolinic acid (DPA), the release of which is considered the crucial step for inactivating it under mild pressure and temperature conditions. However, the process of how the spore releases DPA in response to pressure remains obscure. Here we apply 1 H high-resolution high-pressure NMR spectroscopy, for the first time, to the spore suspension of Bacillus subtilis natto and monitor directly and in real-time the leaking process of DPA in response to pressure of 200MPa at 20°C. We find that about one third of the total DPA leaks immediately upon applying pressure, but that the rest leaks slowly in hrs upon decreasing the pressure. Once DPA is fully released from the spore, the proteins of the spore become easily denatured at a mild temperature, e.g., 80°C, much below the temperature commonly used to inactivate spores (121°C). The success of the present experiment opens a new avenue for studying bacterial spores and cells at the molecular level in response to pressure, temperature and other perturbations. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Resistance to and killing by the sporicidal microbicide peracetic acid.

    Science.gov (United States)

    Leggett, Mark J; Schwarz, J Spencer; Burke, Peter A; Mcdonnell, Gerald; Denyer, Stephen P; Maillard, Jean-Yves

    2015-03-01

    To elucidate the mechanisms of spore resistance to and killing by the oxidizing microbicide peracetic acid (PAA). Mutants of Bacillus subtilis lacking specific spore structures were used to identify resistance properties in spores and to understand the mechanism of action of PAA. We also assessed the effect of PAA treatment on a number of spore properties including heat tolerance, membrane integrity and germination. The spore coat is essential for spore PAA resistance as spores with defective coats were greatly sensitized to PAA treatment. Small acid-soluble spore proteins apparently provide no protection against PAA. Defects in spore germination, specifically in germination via the GerB and GerK but not the GerA germination receptors, as well as leakage of internal components suggest that PAA is active at the spore inner membrane. It is therefore likely that the inner membrane is the major site of PAA's sporicidal activity. PAA treatment targets the spore membrane, with some of its activity directed specifically against the GerB and GerK germination receptors. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. A study of Ganoderma lucidum spores by FTIR microspectroscopy

    Science.gov (United States)

    Wang, Xin; Chen, Xianliang; Qi, Zeming; Liu, Xingcun; Li, Weizu; Wang, Shengyi

    2012-06-01

    In order to obtain unique information of Ganoderma lucidum spores, FTIR microspectroscopy was used to study G. lucidum spores from Anhui Province (A), Liaoning Province (B) and Shangdong Province (C) of China. IR micro-spectra were acquired with high-resolution and well-reproducibility. The IR spectra of G. lucidum spores from different areas were similar and mainly made up of the absorption bands of polysaccharide, sterols, proteins, fatty acids, etc. The results of curve fitting indicated the protein secondary structures were dissimilar among the above G. lucidum spores. To identify G. lucidum spores from different areas, the H1078/H1640 value might be a potentially useful factor, furthermore FTIR microspectroscopy could realize this identification efficiently with the help of hierarchical cluster analysis. The result indicates FTIR microspectroscopy is an efficient tool for identification of G. lucidum spores from different areas. The result also suggests FTIR microspectroscopy is a potentially useful tool for the study of TCM.

  2. A Clostridium difficile-Specific, Gel-Forming Protein Required for Optimal Spore Germination

    Directory of Open Access Journals (Sweden)

    M. Lauren Donnelly

    2017-01-01

    Full Text Available Clostridium difficile is a Gram-positive spore-forming obligate anaerobe that is a leading cause of antibiotic-associated diarrhea worldwide. In order for C. difficile to initiate infection, its aerotolerant spore form must germinate in the gut of mammalian hosts. While almost all spore-forming organisms use transmembrane germinant receptors to trigger germination, C. difficile uses the pseudoprotease CspC to sense bile salt germinants. CspC activates the related subtilisin-like protease CspB, which then proteolytically activates the cortex hydrolase SleC. Activated SleC degrades the protective spore cortex layer, a step that is essential for germination to proceed. Since CspC incorporation into spores also depends on CspA, a related pseudoprotease domain, Csp family proteins play a critical role in germination. However, how Csps are incorporated into spores remains unknown. In this study, we demonstrate that incorporation of the CspC, CspB, and CspA germination regulators into spores depends on CD0311 (renamed GerG, a previously uncharacterized hypothetical protein. The reduced levels of Csps in gerG spores correlate with reduced responsiveness to bile salt germinants and increased germination heterogeneity in single-spore germination assays. Interestingly, asparagine-rich repeat sequences in GerG’s central region facilitate spontaneous gel formation in vitro even though they are dispensable for GerG-mediated control of germination. Since GerG is found exclusively in C. difficile, our results suggest that exploiting GerG function could represent a promising avenue for developing C. difficile-specific anti-infective therapies.

  3. Acid and bile tolerance of spore-forming lactic acid bacteria.

    Science.gov (United States)

    Hyronimus, B; Le Marrec, C; Sassi, A H; Deschamps, A

    2000-11-01

    Criteria for screening probiotics such as bile tolerance and resistance to acids were studied with 13 spore-forming lactic acid producing bacteria. Different strains of Sporolactobacillus, Bacillus laevolacticus, Bacillus racemilacticus and Bacillus coagulans grown in MRS broth were subjected to low pH conditions (2, 2.5 and 3) and increasing bile concentrations. Among these microorganisms, Bacillus laevolacticus DSM 6475 and all Sporolactobacillus strains tested except Sporolactobacillus racemicus IAM 12395, were resistant to pH 3. Only Bacillus racemilacticus and Bacillus coagulans strains were tolerant to bile concentrations over 0.3% (w/v).

  4. Biochemical characterization of soluble proteins in pecan [Carya illinoinensis (Wangenh.) K. Koch].

    Science.gov (United States)

    Venkatachalam, Mahesh; Roux, Kenneth H; Sathe, Shridhar K

    2008-09-10

    Pecans (cv. Desirable) contained approximately 10% protein on a dry weight basis. The minimum nitrogen solubility (5.9-7.5%) at 0.25-0.75 M trichloroacetic acid represented the nonprotein nitrogen. Among the solvents assessed for protein solubilization, 0.1 M NaOH was the most effective, while borate saline buffer (pH 8.45) was judged to be optimal for protein solubilization. The protein solubility was minimal in the pH range of 3-7 and significantly increased on either side of this pH range. Increasing the NaCl concentration from 0 to 4 M significantly improved ( approximately 8-fold increase) protein solubilization. Following Osborne protein fractionation, the alkali-soluble glutelin fraction (60.1%) accounted for a major portion of pecan proteins followed by globulin (31.5%), prolamin (3.4%), and albumin (1.5%), respectively. The majority of pecan polypeptides were in the molecular mass range of 12-66 kDa and in the pI range of 4.0-8.3. The pecan globulin fraction was characterized by the presence of several glycoprotein polypeptides. Lysine was the first limiting essential amino acid in the defatted flour, globulin, prolamin, and alkaline glutelin fractions. Leucine and tryptophan were the first limiting essential amino acids in albumin and acid glutelin fractions, respectively. Rabbit polyclonal antibodies detected a range of pecan polypeptides in the 12-60 kDa range, of which the globulin fraction contained the most reactive polypeptides.

  5. Proteins YlaJ and YhcN contribute to the efficiency of spore germination in Bacillus subtilis.

    Science.gov (United States)

    Johnson, Christian L; Moir, Anne

    2017-04-01

    The YlaJ and YhcN spore lipoproteins of Bacillus subtilis contain a common domain, and are of unknown function. Homologues of YlaJ or YhcN are widespread in Bacilli and are also encoded in those Clostridia that use cortex lytic enzymes SleB and CwlJ for cortex hydrolysis during germination. In B. subtilis, we report that single and double mutants lacking YlaJ and/or YhcN show a reduced rate of spore germination in L-alanine, with a delay in loss of heat resistance, release of dipicolinic acid and OD fall. If B. subtilis spores lack the cortex lytic enzyme CwlJ, spore cortex degradation and subsequent outgrowth to form colonies is strictly dependent on the other cortex lytic enzyme SleB, allowing a test of SleB function; in a cwlJ mutant background, the combined loss of both ylaJ and yhcN genes resulted in a spore population in which only 20% of spores germinated and outgrew to form colonies, suggesting that SleB activity is compromised. YlaJ and YhcN have a role in germination that is not yet well defined, but these proteins are likely to contribute, directly or indirectly, to early events in germination, including effective SleB function. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Characterization of a soluble phosphatidic acid phosphatase in bitter melon (Momordica charantia).

    Science.gov (United States)

    Cao, Heping; Sethumadhavan, Kandan; Grimm, Casey C; Ullah, Abul H J

    2014-01-01

    Momordica charantia is often called bitter melon, bitter gourd or bitter squash because its fruit has a bitter taste. The fruit has been widely used as vegetable and herbal medicine. Alpha-eleostearic acid is the major fatty acid in the seeds, but little is known about its biosynthesis. As an initial step towards understanding the biochemical mechanism of fatty acid accumulation in bitter melon seeds, this study focused on a soluble phosphatidic acid phosphatase (PAP, 3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4) that hydrolyzes the phosphomonoester bond in phosphatidate yielding diacylglycerol and P(i). PAPs are typically categorized into two subfamilies: Mg(2+)-dependent soluble PAP and Mg(2+)-independent membrane-associated PAP. We report here the partial purification and characterization of an Mg(2+)-independent PAP activity from developing cotyledons of bitter melon. PAP protein was partially purified by successive centrifugation and UNOsphere Q and S columns from the soluble extract. PAP activity was optimized at pH 6.5 and 53-60 °C and unaffected by up to 0.3 mM MgCl2. The K(m) and Vmax values for dioleoyl-phosphatidic acid were 595.4 µM and 104.9 ηkat/mg of protein, respectively. PAP activity was inhibited by NaF, Na(3)VO(4), Triton X-100, FeSO4 and CuSO4, but stimulated by MnSO4, ZnSO4 and Co(NO3)2. In-gel activity assay and mass spectrometry showed that PAP activity was copurified with a number of other proteins. This study suggests that PAP protein is probably associated with other proteins in bitter melon seeds and that a new class of PAP exists as a soluble and Mg(2+)-independent enzyme in plants.

  7. Soluble Non-ammonia Nitrogen in Ruminal and Omasal Digesta of Korean Native Steers Supplemented with Soluble Proteins

    Directory of Open Access Journals (Sweden)

    C. W. Choi

    2012-09-01

    Full Text Available An experiment was conducted to study the effect of soluble protein supplements on concentration of soluble non-ammonia nitrogen (SNAN in the liquid phase of ruminal (RD and omasal digesta (OD of Korean native steers, and to investigate diurnal pattern in SNAN concentration in RD and OD. Three ruminally cannulated Korean native steers in a 3×3 Latin square design consumed a basal diet of rice straw and corn-based concentrate (control, and that supplemented (kg/d DM basis with intact casein (0.24; IC or acid hydrolyzed casein (0.46; AHC. Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 2.0 h intervals after a morning feeding. The SNAN fractions (free amino acid (AA, peptide and soluble protein in RD and OD were assessed using the ninhydrin assay. Concentrations of free AA and total SNAN in RD were significantly (p<0.05 lower than those in OD. Although free AA concentration was relatively high, mean peptide was quantitatively the most important fraction of total SNAN in both RD and OD, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis of Korean native steers. Diurnal variation in peptide concentration in OD for the soluble protein supplemented diets during the feeding cycle peaked 2 h post-feeding and decreased thereafter whereas that for the control was relatively constant during the entire feeding cycle. Diurnal variation in peptide concentration was rather similar between RD and OD.

  8. Optimization of translation profiles enhances protein expression and solubility.

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Hess

    Full Text Available mRNA is translated with a non-uniform speed that actively coordinates co-translational folding of protein domains. Using structure-based homology we identified the structural domains in epoxide hydrolases (EHs and introduced slow-translating codons to delineate the translation of single domains. These changes in translation speed dramatically improved the solubility of two EHs of metagenomic origin in Escherichia coli. Conversely, the importance of transient attenuation for the folding, and consequently solubility, of EH was evidenced with a member of the EH family from Agrobacterium radiobacter, which partitions in the soluble fraction when expressed in E. coli. Synonymous substitutions of codons shaping the slow-transiting regions to fast-translating codons render this protein insoluble. Furthermore, we show that low protein yield can be enhanced by decreasing the free folding energy of the initial 5'-coding region, which can disrupt mRNA secondary structure and enhance ribosomal loading. This study provides direct experimental evidence that mRNA is not a mere messenger for translation of codons into amino acids but bears an additional layer of information for folding, solubility and expression level of the encoded protein. Furthermore, it provides a general frame on how to modulate and fine-tune gene expression of a target protein.

  9. Protein Solubility as Quality Index for Processed Soybean

    Directory of Open Access Journals (Sweden)

    Rodica Căpriţă

    2010-05-01

    Full Text Available Protein quality of soybean meal (SBM is linked to both the reduction of antinutritional factors (ANFs, and the optimization of protein digestibility. Both insufficient- and over-heating result in poor quality SBM. Inadequate heating fails to completely destroy the ANFs, which may have a detrimental impact on animal performance, while excessive heating reduces the availability of lysine via the Maillard reaction and possibly, to a lesser extent, of other amino acids. The objective of our study was to compare some biochemical laboratory procedures for assessing quality of SBM: urease index (UI, protein dispersibility index (PDI, KOH protein solubility (PS, and nitrogen solubility index (NSI. The experimental data reveal that UI is not useful to determine excessive heat treatment since additional heating has no effect on the urease index. KOH protein solubility remains high, during initial heat treatment. In marked contrast, the PDI and NSI decreased incrementally from 78% to 20% and from 97% to 60%, respectively, when heating 0 to 30 minutes. Combing the PDI test with the urease test could be useful to monitor soybean quality. SBM containing low UI (0.3 or below and high PDI (40 to 45% may indicate that the sample is definitely high quality because it has been adequately heat processed, but not overprocessed.

  10. Identification of the immunogenic spore and vegetative proteins of Bacillus anthracis vaccine strain A16R.

    Directory of Open Access Journals (Sweden)

    Xiankai Liu

    Full Text Available Immunoproteomics was used to screen the immunogenic spore and vegetative proteins of Bacillus anthracis vaccine strain A16R. The spore and vegetative proteins were separated by 2D gel electrophoresis and transferred to polyvinylidene difluoride membranes, and then western blotting was performed with rabbit immune serum against B.anthracis live spores. Immunogenic spots were cut and digested by trypsin. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry was performed to identify the proteins. As a result, 11 and 45 immunogenic proteins were identified in the spores and vegetative cells, respectively; 26 of which have not been reported previously. To verify their immunogenicity, 12 of the identified proteins were selected to be expressed, and the immune sera from the mice vaccinated by the 12 expressed proteins, except BA0887, had a specific western blot band with the A16R whole cellular lytic proteins. Some of these immunogenic proteins might be used as novel vaccine candidates themselves or for enhancing the protective efficacy of a protective-antigen-based vaccine.

  11. Use of Fatty Acid Methyl Ester Profiles for Discrimination of Bacillus cereus T-Strain Spores Grown on Different Media▿

    Science.gov (United States)

    Ehrhardt, Christopher J.; Chu, Vivian; Brown, TeeCie; Simmons, Terrie L.; Swan, Brandon K.; Bannan, Jason; Robertson, James M.

    2010-01-01

    The goal of this study was to determine if cellular fatty acid methyl ester (FAME) profiling could be used to distinguish among spore samples from a single species (Bacillus cereus T strain) that were prepared on 10 different medium formulations. To analyze profile differences and identify FAME biomarkers diagnostic for the chemical constituents in each sporulation medium, a variety of statistical techniques were used, including nonmetric multidimensional scaling (nMDS), analysis of similarities (ANOSIM), and discriminant function analysis (DFA). The results showed that one FAME biomarker, oleic acid (18:1 ω9c), was exclusively associated with spores grown on Columbia agar supplemented with sheep blood and was indicative of blood supplements that were present in the sporulation medium. For spores grown in other formulations, multivariate comparisons across several FAME biomarkers were required to discern profile differences. Clustering patterns in nMDS plots and R values from ANOSIM revealed that dissimilarities among FAME profiles were most pronounced when spores grown with disparate sources of complex additives or protein supplements were compared (R > 0.8), although other factors also contributed to FAME differences. DFA indicated that differentiation could be maximized with a targeted subset of FAME variables, and the relative contributions of branched FAME biomarkers to group dissimilarities changed when different media were compared. When taken together, these analyses indicate that B. cereus spore samples grown in different media can be resolved with FAME profiling and that this may be a useful technique for providing intelligence about the production methods of Bacillus organisms in a forensic investigation. PMID:20097814

  12. Use of fatty acid methyl ester profiles for discrimination of Bacillus cereus T-strain spores grown on different media.

    Science.gov (United States)

    Ehrhardt, Christopher J; Chu, Vivian; Brown, TeeCie; Simmons, Terrie L; Swan, Brandon K; Bannan, Jason; Robertson, James M

    2010-03-01

    The goal of this study was to determine if cellular fatty acid methyl ester (FAME) profiling could be used to distinguish among spore samples from a single species (Bacillus cereus T strain) that were prepared on 10 different medium formulations. To analyze profile differences and identify FAME biomarkers diagnostic for the chemical constituents in each sporulation medium, a variety of statistical techniques were used, including nonmetric multidimensional scaling (nMDS), analysis of similarities (ANOSIM), and discriminant function analysis (DFA). The results showed that one FAME biomarker, oleic acid (18:1 omega9c), was exclusively associated with spores grown on Columbia agar supplemented with sheep blood and was indicative of blood supplements that were present in the sporulation medium. For spores grown in other formulations, multivariate comparisons across several FAME biomarkers were required to discern profile differences. Clustering patterns in nMDS plots and R values from ANOSIM revealed that dissimilarities among FAME profiles were most pronounced when spores grown with disparate sources of complex additives or protein supplements were compared (R > 0.8), although other factors also contributed to FAME differences. DFA indicated that differentiation could be maximized with a targeted subset of FAME variables, and the relative contributions of branched FAME biomarkers to group dissimilarities changed when different media were compared. When taken together, these analyses indicate that B. cereus spore samples grown in different media can be resolved with FAME profiling and that this may be a useful technique for providing intelligence about the production methods of Bacillus organisms in a forensic investigation.

  13. Determination of soluble protein contents from RVNRL

    International Nuclear Information System (INIS)

    Wan Manshol Wan Zin; Nurulhuda Othman

    1996-01-01

    This project was carried out to determine the soluble protein contents on RVNRL film vulcanisates, with respect to the RVNRL storage time, gamma irradiation dose absorbed by the latex and the effect of different leaching time and leaching conditions. These three factors are important in the hope to determine the best possible mean of minimizing the soluble protein contents in products made from RVNRL. Within the nine months storage period employed in the study, the results show that, the longer the storage period the less the soluble protein extracted from the film samples. Gamma irradiation dose absorbed by the samples, between 5.3 kGy to 25.2 kGy seems to influence the soluble protein contents of the RVNRL films vulcanisates. The higher the dose the more was the soluble protein extracted from the film samples. At an absorbed dose of 5.3 kGy and 25.2 kGy, the soluble contents were 0. 198 mg/ml and 0.247 mg/ml respectively. At a fixed leaching temperature, the soluble proteins increases with leaching time and at a fixed leaching time, the soluble proteins increases with leaching temperature. ne highest extractable protein contents was determined at a leaching time of 10 minutes and leaching temperature of 90'C The protein analysis were done by using Modified Lowry Method

  14. Enzyme-driven Bacillus spore coat degradation leading to spore killing.

    Science.gov (United States)

    Mundra, Ruchir V; Mehta, Krunal K; Wu, Xia; Paskaleva, Elena E; Kane, Ravi S; Dordick, Jonathan S

    2014-04-01

    The bacillus spore coat confers chemical and biological resistance, thereby protecting the core from harsh environments. The primarily protein-based coat consists of recalcitrant protein crosslinks that endow the coat with such functional protection. Proteases are present in the spore coat, which play a putative role in coat degradation in the environment. However these enzymes are poorly characterized. Nonetheless given the potential for proteases to catalyze coat degradation, we screened 10 commercially available proteases for their ability to degrade the spore coats of B. cereus and B. anthracis. Proteinase K and subtilisin Carlsberg, for B. cereus and B. anthracis spore coats, respectively, led to a morphological change in the otherwise impregnable coat structure, increasing coat permeability towards cortex lytic enzymes such as lysozyme and SleB, thereby initiating germination. Specifically in the presence of lysozyme, proteinase K resulted in 14-fold faster enzyme induced germination and exhibited significantly shorter lag times, than spores without protease pretreatment. Furthermore, the germinated spores were shown to be vulnerable to a lytic enzyme (PlyPH) resulting in effective spore killing. The spore surface in response to proteolytic degradation was probed using scanning electron microscopy (SEM), which provided key insights regarding coat degradation. The extent of coat degradation and spore killing using this enzyme-based pretreatment approach is similar to traditional, yet far harsher, chemical decoating methods that employ detergents and strong denaturants. Thus the enzymatic route reduces the environmental burden of chemically mediated spore killing, and demonstrates that a mild and environmentally benign biocatalytic spore killing is achievable. © 2013 Wiley Periodicals, Inc.

  15. Influence of biopolymers on the solubility of branched-chain amino acids and stability of their solutions.

    Science.gov (United States)

    Hong, Chi Rac; Lee, Gyu Whan; Paik, Hyun-Dong; Chang, Pahn-Shick; Choi, Seung Jun

    2018-01-15

    This study confirmed the possibility of biopolymer-type stabilizers to increase the saturation concentration of branched-chain amino acids by preventing their crystallization/precipitation. Although microfluidization increased the initial solubility, it failed to increase the saturation concentration of the branched-chain amino acids. The saturation concentration of the branched-chain amino acids increased from 3.81% to 4.42% and 4.85% after the incorporation of food hydrocolloids and proteins, respectively. However, the branched-chain amino acids:stabilizer ratio did not affect the solubility. In the case of food hydrocolloid-based solutions, crystal formation and growth of branched-chain amino acids occurred during storage, resulting in the precipitation of branched-chain amino acid crystals. However, food proteins effectively increased the stability of the solubilized branched-chain amino acids. The improved solubility and stability of the solubilized branched-chain amino acids could be attributed to interactions between the functional groups (carboxyl, amine, sulfate, aliphatic, aromatic, etc.) of the stabilizer and the branched-chain amino acid molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Solubility of xenon in amino-acid solutions. II. Nine less-soluble amino acids

    Science.gov (United States)

    Kennan, Richard P.; Himm, Jeffrey F.; Pollack, Gerald L.

    1988-05-01

    Ostwald solubility (L) of xenon gas, as the radioisotope 133Xe, has been measured as a function of solute concentration, at 25.0 °C, in aqueous solutions of nine amino acids. The amino-acid concentrations investigated covered much of their solubility ranges in water, viz., asparagine monohydrate (0-0.19 M), cysteine (0-1.16 M), glutamine (0-0.22 M), histidine (0-0.26 M), isoleucine (0-0.19 M), methionine (0-0.22 M), serine (0-0.38 M), threonine (0-1.4 M), and valine (0-0.34 M). We have previously reported solubility results for aqueous solutions of six other, generally more soluble, amino acids (alanine, arginine, glycine, hydroxyproline, lysine, and proline), of sucrose and sodium chloride. In general, L decreases approximately linearly with increasing solute concentration in these solutions. If we postulate that the observed decreases in gas solubility are due to hydration, the results under some assumptions can be used to calculate hydration numbers (H), i.e., the number of H2O molecules associated with each amino-acid solute molecule. The average values of hydration number (H¯) obtained at 25.0 °C are 15.3±1.5 for asparagine, 6.8±0.3 for cysteine, 11.5±1.1 for glutamine, 7.3±0.7 for histidine, 5.9±0.4 for isoleucine, 10.6±0.8 for methionine, 11.2±1.3 for serine, 7.7± 1.0 for threonine, and 6.6±0.6 for valine. We have also measured the temperature dependence of solubility L(T) from 5-40 °C for arginine, glycine, and proline, and obtained hydration numbers H¯(T) in this range. Between 25-40 °C, arginine has an H¯ near zero. This may be evidence for an attractive interaction between xenon and arginine molecules in aqueous solution.

  17. Biomarkers of Aspergillus spores: Strain typing and protein identification

    Czech Academy of Sciences Publication Activity Database

    Šulc, Miroslav; Pešlová, Kateřina; Žabka, Martin; Hajdúch, M.; Havlíček, Vladimír

    2009-01-01

    Roč. 280, 1-3 (2009), s. 162-168 ISSN 1387-3806 R&D Projects: GA MŠk LC07017; GA ČR GP203/05/P575 Institutional research plan: CEZ:AV0Z50200510 Keywords : aspergillus * spore * protein Subject RIV: EE - Microbiology, Virology Impact factor: 2.117, year: 2009

  18. Spores of the mycorrhizal fungus Glomus mosseae host yeasts that solubilize phosphate and accumulate polyphosphates.

    Science.gov (United States)

    Mirabal Alonso, Loreli; Kleiner, Diethelm; Ortega, Eduardo

    2008-04-01

    The present paper reports the presence of bacteria and yeasts tightly associated with spores of an isolate of Glomus mosseae. Healthy spores were surface disinfected by combining chloramine-T 5%, Tween-40, and cephalexin 2.5 g L(-1) (CTCf). Macerates of these spores were incubated on agar media, microorganisms were isolated, and two yeasts were characterized (EndoGm1, EndoGm11). Both yeasts were able to solubilize low-soluble P sources (Ca and Fe phosphates) and accumulate polyphosphates (polyPs). Sequence analysis of 18S ribosomal deoxyribonucleic acid showed that the yeasts belong to the genera Rhodotorula or Rhodosporidium (EndoGm1) and Cryptococcus (EndoGm11). Results from inoculation experiments showed an effect of the spore-associated yeasts on the root growth of rice, suggesting potential tripartite interactions with mycorrhizal fungi and plants.

  19. Solubility of cefoxitin acid in different solvent systems

    International Nuclear Information System (INIS)

    Yuan, Fuhong; Wang, Yongli; Xiao, Liping; Huang, Qiaoyin; Xu, Jinchao; Jiang, Chen; Hao, Hongxun

    2016-01-01

    Highlights: • The solubility of cefoxitin acid in different solvent systems was measured. • Three models were used to correlate the solubility data. • The dissolution enthalpy of the dissolution process was calculated. - Abstract: Cefoxitin acid is one kind of important pharmaceutical intermediate. Its solubility is crucial for designing and optimizing the crystallization processes. In this work, the solubility of cefoxitin acid in organic solvents (methanol, acetonitrile, ethanol, isopropanol, n-propanol and ethyl acetate), water and water-methanol mixtures was measured spectrophotometrically using a shake-flask method within the temperature range 278.15–303.15 K. PXRD data and the Karl Fischer method were used to verify the crystal form stability of cefoxitin acid in the solubility measuring process. The melting points, the enthalpy and entropy of fusion were estimated. Results showed that the solubility of cefoxitin acid increases with the increasing temperature in all tested solvents in this work, and the solubility of cefoxitin acid increases with the increasing methanol concentration in water-methanol mixtures. The experimental solubility values were well correlated using the modified Apelblat equation, NRTL model and CNIBS/R-K model. An equation proposed by Williamson was adopted to calculate the molar enthalpy during the dissolution process.

  20. Fermentable soluble fibres spare amino acids in healthy dogs fed a low-protein diet.

    Science.gov (United States)

    Wambacq, Wendy; Rybachuk, Galena; Jeusette, Isabelle; Rochus, Kristel; Wuyts, Brigitte; Fievez, Veerle; Nguyen, Patrick; Hesta, Myriam

    2016-06-28

    Research in cats has shown that increased fermentation-derived propionic acid and its metabolites can be used as alternative substrates for gluconeogenesis, thus sparing amino acids for other purposes. This amino acid sparing effect could be of particular interest in patients with kidney or liver disease, where this could reduce the kidneys'/liver's burden of N-waste removal. Since dogs are known to have a different metabolism than the obligatory carnivorous cat, the main objective of this study was to assess the possibility of altering amino acid metabolism through intestinal fermentation in healthy dogs. This was studied by supplementing a low-protein diet with fermentable fibres, hereby providing an initial model for future studies in dogs suffering from renal/liver disease. Eight healthy dogs were randomly assigned to one of two treatment groups: sugar beet pulp and guar gum mix (SF: soluble fibre, estimated to mainly stimulate propionic acid production) or cellulose (IF: insoluble fibre). Treatments were incorporated into a low-protein (17 %) extruded dry diet in amounts to obtain similar total dietary fibre (TDF) contents for both diets (9.4 % and 8.2 % for the SF and IF diet, respectively) and were tested in a 4-week crossover feeding trial. Apparent faecal nitrogen digestibility and post-prandial fermentation metabolites in faeces and plasma were evaluated. Dogs fed the SF diet showed significantly higher faecal excretion of acetic and propionic acid, resulting in a higher total SCFA excretion compared to IF. SF affected the three to six-hour postprandial plasma acylcarnitine profile by significantly increasing AUC of acetyl-, propionyl-, butyryl- + isobutyryl-, 3-OH-butyryl-, 3-OH-isovaleryl- and malonyl-L-carnitine. Moreover, the amino acid plasma profile at that time was modified as leucine + isoleucine concentrations were significantly increased by SF, and a similar trend for phenylalanine and tyrosine's AUC was found. These results indicate

  1. Ptaquiloside in bracken spores from Britain

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Schmidt, Bjørn; Sheffield, Elizabeth

    2013-01-01

    Secondary metabolites from bracken fern (Pteridium aquilinum (L.) Kuhn) are suspected of causing cancer in humans. The main carcinogen is the highly water-soluble norsesquiterpene glucoside ptaquiloside, which may be ingested by humans through food, e.g. via contaminated water, meat or milk. It has...... been postulated that carcinogens could also be ingested through breathing air containing bracken spores. Ptaquiloside has not previously been identified in bracken spores. The aim of the study was to determine whether ptaquiloside is present in bracken spores, and if so, to estimate its content...

  2. On the solubility of nicotinic acid and isonicotinic acid in water and organic solvents

    International Nuclear Information System (INIS)

    Abraham, Michael H.; Acree, William E.

    2013-01-01

    Highlights: ► Solubilities of nicotinic acid and isonicotinic acids in organicsolvents have been determined. ► Solubilities are used to calculate Abraham descriptors for the two acids. ► These descriptors then yield water-solvent and gas-solvent partitions into numerous solvents. ► The solubility of the neutral acids in water is obtained. ► The method is straightforward and can be applied to any set of compound solubilities. -- Abstract: We have determined the solubility of nicotinic acid in four solvents and the solubility of isonicotinic acid in another four solvents. These results, together with literature data on the solubility of nicotinic acid in five other organic solvents and isonicotinic acid in four other organic solvents, have been analyzed through two linear Gibbs energy relationships in order to extract compound properties, or descriptors, that encode various solute–solvent interactions. The descriptors for nicotinic acid and isonicotinic acid can then be used in known equations for partition of solutes between water and organic solvents to predict partition coefficients and then further solubility in a host of organic solvents, as well as to predict a number of other physicochemical properties

  3. Structure, diversity and evolution of protein toxins from spore-forming entomopathogenic bacteria

    NARCIS (Netherlands)

    Maagd, de R.A.; Bravo, A.; Berry, C.; Crickmore, N.; Schnepf, H.E.

    2003-01-01

    Gram-positive spore-forming entomopathogenic bacteria can utilize a large variety of protein toxins to help them invade, infect, and finally kill their hosts, through their action on the insect midgut. These toxins belong to a number of homology groups containing a diversity of protein structures

  4. Solubility of sparingly soluble drug derivatives of anthranilic acid.

    Science.gov (United States)

    Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra

    2011-03-24

    This work is a continuation of our systematic study of the solubility of pharmaceuticals (Pharms). All substances here are derivatives of anthranilic acid, and have an anti-inflammatory direction of action (niflumic acid, flufenamic acid, and diclofenac sodium). The basic thermal properties of pure Pharms, i.e., melting and glass-transition temperatures as well as the enthalpy of melting, have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The equilibrium mole fraction solubilities of three pharmaceuticals were measured in a range of temperatures from 285 to 355 K in three important solvents for Pharm investigations: water, ethanol, and 1-octanol using a dynamic method and spectroscopic UV-vis method. The experimental solubility data have been correlated by means of the commonly known G(E) equation: the NRTL, with the assumption that the systems studied here have revealed simple eutectic mixtures. pK(a) precise measurement values have been investigated with the Bates-Schwarzenbach spectrophotometric method. © 2011 American Chemical Society

  5. Comparing side chain packing in soluble proteins, protein-protein interfaces, and transmembrane proteins.

    Science.gov (United States)

    Gaines, J C; Acebes, S; Virrueta, A; Butler, M; Regan, L; O'Hern, C S

    2018-05-01

    We compare side chain prediction and packing of core and non-core regions of soluble proteins, protein-protein interfaces, and transmembrane proteins. We first identified or created comparable databases of high-resolution crystal structures of these 3 protein classes. We show that the solvent-inaccessible cores of the 3 classes of proteins are equally densely packed. As a result, the side chains of core residues at protein-protein interfaces and in the membrane-exposed regions of transmembrane proteins can be predicted by the hard-sphere plus stereochemical constraint model with the same high prediction accuracies (>90%) as core residues in soluble proteins. We also find that for all 3 classes of proteins, as one moves away from the solvent-inaccessible core, the packing fraction decreases as the solvent accessibility increases. However, the side chain predictability remains high (80% within 30°) up to a relative solvent accessibility, rSASA≲0.3, for all 3 protein classes. Our results show that ≈40% of the interface regions in protein complexes are "core", that is, densely packed with side chain conformations that can be accurately predicted using the hard-sphere model. We propose packing fraction as a metric that can be used to distinguish real protein-protein interactions from designed, non-binding, decoys. Our results also show that cores of membrane proteins are the same as cores of soluble proteins. Thus, the computational methods we are developing for the analysis of the effect of hydrophobic core mutations in soluble proteins will be equally applicable to analyses of mutations in membrane proteins. © 2018 Wiley Periodicals, Inc.

  6. Synergistic Effects of High Hydrostatic Pressure, Mild Heating, and Amino Acids on Germination and Inactivation of Clostridium sporogenes Spores

    Science.gov (United States)

    Ishimori, Takateru; Takahashi, Katsutoshi; Goto, Masato; Nakagawa, Suguru; Kasai, Yoshiaki; Konagaya, Yukifumi; Batori, Hiroshi; Kobayashi, Atsushi

    2012-01-01

    The synergistic effects of high hydrostatic pressure (HHP), mild heating, and amino acids on the germination of Clostridium sporogenes spores were examined by determining the number of surviving spores that returned to vegetative growth after pasteurization following these treatments. Pressurization at 200 MPa at a temperature higher than 40°C and treatment with some of the 19 l-amino acids at 10 mM or higher synergistically facilitated germination. When one of these factors was omitted, the level of germination was insignificant. Pressures of 100 and 400 MPa were less effective than 200 MPa. The spores were effectively inactivated by between 1.8 and 4.8 logs by pasteurization at 80°C after pressurization at 200 MPa at 45°C for 120 min with one of the amino acids with moderate hydrophobicity, such as Leu, Phe, Cys Met, Ala, Gly, or Ser. However, other amino acids showed poor inactivation effects of less than 0.9 logs. Spores in solutions containing 80 mM of either Leu, Phe, Cys, Met, Ala, Gly, or Ser were successfully inactivated by pasteurization by more than 5.4 logs after pressurization at 200 MPa at 70°C for 15 to 120 min. Ala and Met reduced the spore viability by 2.8 and 1.8 logs, respectively, by pasteurization at a concentration of 1 mM under 200 MPa at 70°C. These results indicate that germination of the spores is facilitated by a combination of high hydrostatic pressure, mild heating, and amino acids. PMID:22983975

  7. The Role of Aquaporins in pH-Dependent Germination of Rhizopus delemar Spores.

    Directory of Open Access Journals (Sweden)

    Tidhar Turgeman

    Full Text Available Rhizopus delemar and associated species attack a wide range of fruit and vegetables after harvest. Host nutrients and acidic pH are required for optimal germination of R. delemar, and we studied how this process is triggered. Glucose induced spore swelling in an acidic environment, expressed by an up to 3-fold increase in spore diameter, whereas spore diameter was smaller in a neutral environment. When suspended in an acidic environment, the spores started to float, indicating a change in their density. Treatment of the spores with HgCl2, an aquaporin blocker, prevented floating and inhibited spore swelling and germ-tube emergence, indicating the importance of water uptake at the early stages of germination. Two putative candidate aquaporin-encoding genes-RdAQP1 and RdAQP2-were identified in the R. delemar genome. Both presented the conserved NPA motif and six-transmembrane domain topology. Expressing RdAQP1 and RdAQP2 in Arabidopsis protoplasts increased the cells' osmotic water permeability coefficient (Pf compared to controls, indicating their role as water channels. A decrease in R. delemar aquaporin activity with increasing external pH suggested pH regulation of these proteins. Substitution of two histidine (His residues, positioned on two loops facing the outer side of the cell, with alanine eliminated the pH sensing resulting in similar Pf values under acidic and basic conditions. Since hydration is critical for spore switching from the resting to activate state, we suggest that pH regulation of the aquaporins can regulate the initial phase of R. delemar spore germination, followed by germ-tube elongation and host-tissue infection.

  8. Mechanism of Sporicidal Activity for the Synergistic Combination of Peracetic Acid and Hydrogen Peroxide.

    Science.gov (United States)

    Leggett, Mark J; Schwarz, J Spencer; Burke, Peter A; McDonnell, Gerald; Denyer, Stephen P; Maillard, Jean-Yves

    2016-02-15

    There is still great interest in controlling bacterial endospores. The use of chemical disinfectants and, notably, oxidizing agents to sterilize medical devices is increasing. With this in mind, hydrogen peroxide (H2O2) and peracetic acid (PAA) have been used in combination, but until now there has been no explanation for the observed increase in sporicidal activity. This study provides information on the mechanism of synergistic interaction of PAA and H2O2 against bacterial spores. We performed investigations of the efficacies of different combinations, including pretreatments with the two oxidizers, against wild-type spores and a range of spore mutants deficient in the spore coat or small acid-soluble spore proteins. The concentrations of the two biocides were also measured in the reaction vessels, enabling the assessment of any shift from H2O2 to PAA formation. This study confirmed the synergistic activity of the combination of H2O2 and PAA. However, we observed that the sporicidal activity of the combination is largely due to PAA and not H2O2. Furthermore, we observed that the synergistic combination was based on H2O2 compromising the spore coat, which was the main spore resistance factor, likely allowing better penetration of PAA and resulting in the increased sporicidal activity. Copyright © 2016 Leggett et al.

  9. Sensitizing Clostridium difficile Spores With Germinants on Skin and Environmental Surfaces Represents a New Strategy for Reducing Spores via Ambient Mechanisms

    Directory of Open Access Journals (Sweden)

    Michelle Marie Nerandzic

    2017-10-01

    Full Text Available Background: Clostridium difficile is a leading cause of healthcare-associated infections worldwide. Prevention of C. difficile transmission is challenging because spores are not killed by alcohol-based hand sanitizers or many commonly used disinfectants. One strategy to control spores is to induce germination, thereby rendering the spores more susceptible to benign disinfection measures and ambient stressors. Methods/Results: C. difficile spores germinated on skin after a single application of cholic acid-class bile salts and co-germinants; for 4 C. difficile strains, recovery of viable spores from skin was reduced by ~0.3 log10CFU to 2 log10CFU after 2 hours and ~1 log10CFU to >2.5 log 10CFU after 24 hours. The addition of taurocholic acid to 70% and 30% ethanol significantly enhanced reduction of viable spores on skin and on surfaces. Desiccation, and to a lesser extent the presence of oxygen, were identified as the stressors responsible for reductions of germinated spores on skin and surfaces. Additionally, germinated spores became susceptible to killing by pH 1.5 hydrochloric acid, suggesting that germinated spores that remain viable on skin and surfaces might be killed by gastric acid after ingestion. Antibiotic-treated mice did not become colonized after exposure to germinated spores, whereas 100% of mice became colonized after exposure to the same quantity of dormant spores. Conclusions: Germination could provide a new approach to reduce C. difficile spores on skin and in the environment and to render surviving spores less capable of causing infection. Our findings suggest that it may be feasible to develop alcohol-based hand sanitizers containing germinants that reduce spores on hands.

  10. Characterization of Acid Soluble Collagen from Redbelly Yellowtail Fusilier Fish Skin (Caesio cuning

    Directory of Open Access Journals (Sweden)

    Ika Astiana

    2016-04-01

    Full Text Available Fish skin can be used as raw material for producing collagen. The collagen can be extracted by chemical or combination of chemical and enzymatic processes. Extraction of collagen chemically can do with the acid process that produces acid soluble collagen (ASC. This study aimed to determine the optimum concentration and time of pretreatment and extraction, also to determine the characteristics of the acid soluble collagen from the skin of yellow tail fish. Extraction of collagen done by pretreatment using NaOH at the concentration of 0.05; 0.1; and 0.15 M and extraction using acetic acid at the concentration of 0.3; 0.5; and 0.7 M. Pretreatment NaOH with concentration 0.05 M and soaking time of 8 hours is the best combination for eliminating non collagen protein. Combination treatment of acetic acid at the concentration of 0.3 M for 3 days obtained the best solubility. The yield of collagen ASC was 18.4±1.49% (db and 5.79±0.47% (wb. Amino acid composition that is dominant in the ASC collagen was glycine (25.09±0.003%, alanine (13.71±0.075%, and proline (12.15±0.132%. Collagen from yellow tail fish skin has α1, α2, β and γ protein structure with the molecular weight of 125, 113, 170-181, and 208 KDa. The transition and melting temperatures of collagen were 67.69oC and 144.4oC. The surface structure of collagen by analysis of SEM has fibers on the surface.

  11. Dynamics of Spore Coat Morphogenesis in Bacillus subtilis

    Science.gov (United States)

    McKenney, Peter T.; Eichenberger, Patrick

    2011-01-01

    SUMMARY Spores of Bacillus subtilis are encased in a protective coat made up of at least 70 proteins. The structure of the spore coat has been examined using a variety of genetic, imaging and biochemical techniques, however, the majority of these studies have focused on mature spores. In this study we use a library of 41 spore coat proteins fused to the Green Fluorescent Protein (GFP) to examine spore coat morphogenesis over the time-course of sporulation. We found considerable diversity in the localization dynamics of coat proteins and were able to establish 6 classes based on localization kinetics. Localization dynamics correlate well with the known transcriptional regulators of coat gene expression. Previously, we described the existence of multiple layers in the mature spore coat. Here, we find that the spore coat initially assembles a scaffold that is organized into multiple layers on one pole of the spore. The coat then encases the spore in multiple coordinated waves. Encasement is driven, at least partially, by transcription of coat genes and deletion of sporulation transcription factors arrests encasement. We also identify the trans-compartment SpoIIIAH-SpoIIQ channel as necessary for encasement. This is the first demonstration of a forespore contribution to spore coat morphogenesis. PMID:22171814

  12. Regulation of expression of a select group of Bacillus anthracis spore coat proteins.

    Science.gov (United States)

    Aronson, Arthur

    2018-04-01

    The spore coat of Bacilli is a relatively complex structure comprised of about 70 species of proteins in 2 or 3 layers. While some are involved in assembly or protection, the regulation of many are not well defined so lacZ transcriptional fusions were constructed to six Bacillus anthracis spore coat genes in order to gain insight into their possible functions. The genes were selected on the basis of the location of the encoded proteins within the coat and distribution among spore forming species. Conditions tested were temperature and media either as solid or liquid. The most extensive differences were for the relatively well expressed fusions to the cotH and cotM genes, which were greatest at 30°C on plates of a nutrient rich medium. The cotJ operon was moderately expressed under all conditions although somewhat higher on enriched plates at 30°C. Cot S was low under all conditions except for a substantial increase in biofilm medium. Cot∝ and cotF were essentially invariant with a somewhat greater expression in the more enriched medium. The capacity of a subset of coat genes to respond to various conditions reflects a flexibility in spore coat structure that may be necessary for adaptation to environmental challenges. This could account, at least in part, for the complexity of this structure.

  13. Solubilities of boric acid in heavy water

    International Nuclear Information System (INIS)

    Nakai, Shigetsugu; Aoi, Hideki; Hayashi, Ken-ichi; Katoh, Taizo; Watanabe, Takashi.

    1988-01-01

    A gravimetric analysis using meta-boric acid (HBO 2 or DBO 2 ) as a weighing form has been developed for solubility measurement. The method gave satisfactory results in preliminary measurement of solubilities of boric acid in light water. By using this method, the solubilities of 10 B enriched D 3 BO 3 in heavy water were measured. The results are as follows; 2.67 (7deg C), 3.52 (15deg C), 5.70 (30deg C), 8.87 (50deg C) and 12.92 (70deg C) w/o, respectively. These values are about 10% lower than those in light water. Thermodynamical consideration based on the data shows that boric acid is the water structure breaker. (author)

  14. Distinction of broken cellular wall Ganoderma lucidum spores and G. lucidum spores using FTIR microspectroscopy

    Science.gov (United States)

    Chen, Xianliang; Liu, Xingcun; Sheng, Daping; Huang, Dake; Li, Weizu; Wang, Xin

    2012-11-01

    In this paper, FTIR microspectroscopy was used to identify broken cellular wall Ganoderma lucidum spores and G. lucidum spores. For IR spectra, broken cellular wall G. lucidum spores and G. lucidum spores were mainly different in the regions of 3000-2800, 1660-1600, 1400-1200 and 1100-1000 cm-1. For curve fitting, the results showed the differences in the protein secondary structures and the polysaccharide structures/content between broken cellular wall G. lucidum spores and G. lucidum spores. Moreover, the value of A1078/A1741 might be a potentially useful factor to distinguish broken cellular wall G. lucidum spores from G. lucidum spores. Additionally, FTIR microspectroscopy could identify broken cellular wall G. lucidum spores and G. lucidum spores accurately when it was combined with hierarchical cluster analysis. The result suggests FTIR microspectroscopy is very simple and efficient for distinction of broken cellular wall G. lucidum spores and G. lucidum spores. The result also indicates FTIR microspectroscopy may be useful for TCM identification.

  15. X-radiation effect on soluble proteins of gastric mucosa

    International Nuclear Information System (INIS)

    Sukhomlinov, B.F.; Chajka, Ya.P.; Fedorovich, A.N.

    1979-01-01

    Using the method of electrophoresis in agar gel soluble proteins of gastric mucosa of rats were separated into 11 fractions. Proteins posessing a proteolytic (pH 1.8) and lipase (pH 7.4) activity were localized within the second and third prealbumin fractions. Soluble proteins of gastric mucosa contain glyco- and lipoproteid complexes. Exposure of rats to 1000 R of X-rays induces quantitative redistribution within the electrophoretic spectrum of soluble proteins and a considerable disturbance of the proteolytic activity of total soluble proteins throughout the entire period of observation (from 10 min to 72h)

  16. The solubilities of benzene polycarboxylic acids in water

    International Nuclear Information System (INIS)

    Apelblat, Alexander; Manzurola, Emanuel; Abo Balal, Nazmia

    2006-01-01

    The solubilities in water of all benzene polycarboxylic acids are discussed, using data determined in this work (benzoic, terephthalic, trimellitic, trimesic, and pyromellitic acids) and available from the literature (benzoic, phthalic, isophthalic, terephthalic, hemimellitic, trimelitic, trimesic, mellophanic, prehnitic, pyromellitic, benzene-pentacarboxylic and mellitic acids). The apparent molar enthalpies of solution at the saturation point for these benzene polycarboxylic acids were determined from the temperature dependence of the solubilities

  17. Characterization of soluble protein BCP 11/24 from bovine corneal epithelium, different from the principal soluble protein BCP 54

    NARCIS (Netherlands)

    Bakker, C.; Pasmans, S.; Verhagen, C.; van Haren, M.; van der Gaag, R.; Hoekzema, R.

    1992-01-01

    The water-soluble fraction of bovine corneal epithelium was analysed by polyacrylamide gel electrophoresis in the presence of SDS (SDS-PAGE). Next to the principal soluble protein BCP 54, which has recently been identified as a corneal aldehyde dehydrogenase (ALDH), another abundant protein was

  18. Relationship between Molecular Structure Characteristics of Feed Proteins and Protein Digestibility and Solubility

    Directory of Open Access Journals (Sweden)

    Mingmei Bai

    2016-08-01

    Full Text Available The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller’s dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as α-helices and β-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area of feed proteins were correlated with their the in vitro digestibility and solubility (p≤0.003; moreover, the relatively quantitative amounts of α-helices, random coils, and α-helix to β-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility (p≤0.004. On the other hand, the percentage of β-sheet structures was negatively correlated with protein in vitro digestibility (p<0.001 and solubility (p = 0.002. These results demonstrate that the molecular structure characteristics of feed proteins are closely related to their in vitro digestibility at 28 h and solubility. Furthermore, the α-helix-to-β-sheet ratio can be used to predict the nutritional value of feed proteins.

  19. Distinction of broken cellular wall Ganoderma lucidum spores and G. lucidum spores using FTIR microspectroscopy.

    Science.gov (United States)

    Chen, Xianliang; Liu, Xingcun; Sheng, Daping; Huang, Dake; Li, Weizu; Wang, Xin

    2012-11-01

    In this paper, FTIR microspectroscopy was used to identify broken cellular wall Ganoderma lucidum spores and G. lucidum spores. For IR spectra, broken cellular wall G. lucidum spores and G. lucidum spores were mainly different in the regions of 3000-2800, 1660-1600, 1400-1200 and 1100-1000 cm(-1). For curve fitting, the results showed the differences in the protein secondary structures and the polysaccharide structures/content between broken cellular wall G. lucidum spores and G. lucidum spores. Moreover, the value of A1078/A1741 might be a potentially useful factor to distinguish broken cellular wall G. lucidum spores from G. lucidum spores. Additionally, FTIR microspectroscopy could identify broken cellular wall G. lucidum spores and G. lucidum spores accurately when it was combined with hierarchical cluster analysis. The result suggests FTIR microspectroscopy is very simple and efficient for distinction of broken cellular wall G. lucidum spores and G. lucidum spores. The result also indicates FTIR microspectroscopy may be useful for TCM identification. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Inactivation kinetics of spores of Bacillus cereus strains treated by a peracetic acid-based disinfectant at different concentrations and temperatures.

    Science.gov (United States)

    Sudhaus, Nadine; Pina-Pérez, Maria Consuelo; Martínez, Antonio; Klein, Günter

    2012-05-01

    The purpose of this study was to assess the effect of a commercial peracetic acid-based disinfectant against spores of Bacillus cereus, to identify the most influential factor for the final number of microorganisms after different disinfection procedures, and to evaluate the nature of the inactivation kinetics. The spores of four different strains of B. cereus (DSM 318, 4312, 4313, and 4384) were treated with five different disinfectant concentrations (0.25%, 0.5%, 1.0%, 1.5%, and 2.0% [w/v]) at three different temperatures (10°C, 15°C, and 20°C) with or without protein load. A higher temperature and PES 15/23 concentration resulted in a higher inactivation. Inactivation of B. cereus strain 4312 was around 2 log₁₀ cycles at 10°C and around 7 log₁₀ at 20°C (conc=1% [w/v] PAA; t=60 min; without protein). The protein load at higher concentrations did not significantly reduce the efficacy of the disinfectant (p>0.05). This article indicates the applicability of the Weibull model to fit the B. cereus disinfectant survival curves. A Monte Carlo simulation was used to carry out a sensitivity analysis, which revealed the most influential factors affecting the final number of microorganisms after the disinfection process.

  1. Lysine Rich Proteins in the Salt-Soluble Protein Fraction of Barley

    DEFF Research Database (Denmark)

    Ingversen, J.; Køie, B.

    1973-01-01

    Fractionation of the protein complex from Emir barley showed that the salt-soluble fraction accounts for 44% of the total lysine content but only for 2.......Fractionation of the protein complex from Emir barley showed that the salt-soluble fraction accounts for 44% of the total lysine content but only for 2....

  2. Lipid recognition propensities of amino acids in membrane proteins from atomic resolution data

    Directory of Open Access Journals (Sweden)

    Morita Mizuki

    2011-12-01

    Full Text Available Abstract Background Protein-lipid interactions play essential roles in the conformational stability and biological functions of membrane proteins. However, few of the previous computational studies have taken into account the atomic details of protein-lipid interactions explicitly. Results To gain an insight into the molecular mechanisms of the recognition of lipid molecules by membrane proteins, we investigated amino acid propensities in membrane proteins for interacting with the head and tail groups of lipid molecules. We observed a common pattern of lipid tail-amino acid interactions in two different data sources, crystal structures and molecular dynamics simulations. These interactions are largely explained by general lipophilicity, whereas the preferences for lipid head groups vary among individual proteins. We also found that membrane and water-soluble proteins utilize essentially an identical set of amino acids for interacting with lipid head and tail groups. Conclusions We showed that the lipophilicity of amino acid residues determines the amino acid preferences for lipid tail groups in both membrane and water-soluble proteins, suggesting that tightly-bound lipid molecules and lipids in the annular shell interact with membrane proteins in a similar manner. In contrast, interactions between lipid head groups and amino acids showed a more variable pattern, apparently constrained by each protein's specific molecular function.

  3. Lipid recognition propensities of amino acids in membrane proteins from atomic resolution data

    International Nuclear Information System (INIS)

    Morita, Mizuki; Katta, AVSK Mohan; Ahmad, Shandar; Mori, Takaharu; Sugita, Yuji; Mizuguchi, Kenji

    2011-01-01

    Protein-lipid interactions play essential roles in the conformational stability and biological functions of membrane proteins. However, few of the previous computational studies have taken into account the atomic details of protein-lipid interactions explicitly. To gain an insight into the molecular mechanisms of the recognition of lipid molecules by membrane proteins, we investigated amino acid propensities in membrane proteins for interacting with the head and tail groups of lipid molecules. We observed a common pattern of lipid tail-amino acid interactions in two different data sources, crystal structures and molecular dynamics simulations. These interactions are largely explained by general lipophilicity, whereas the preferences for lipid head groups vary among individual proteins. We also found that membrane and water-soluble proteins utilize essentially an identical set of amino acids for interacting with lipid head and tail groups. We showed that the lipophilicity of amino acid residues determines the amino acid preferences for lipid tail groups in both membrane and water-soluble proteins, suggesting that tightly-bound lipid molecules and lipids in the annular shell interact with membrane proteins in a similar manner. In contrast, interactions between lipid head groups and amino acids showed a more variable pattern, apparently constrained by each protein's specific molecular function

  4. Gel-free proteomic identification of the Bacillus subtilis insoluble spore coat protein fraction.

    NARCIS (Netherlands)

    Abhyankar, W; Beek, A.T.; Dekker, H.; Kort, R.; Brul, S.; de Koster, C. G.

    2011-01-01

    Species from the genus Bacillus have the ability to form endospores, dormant cellular forms that are able to survive heat and acid preservation techniques commonly used in the food industry. Resistance characteristics of spores towards various environmental stresses are in part attributed to their

  5. Gel-free proteomic identification of the Bacillus subtilis insoluble spore coat protein fraction

    NARCIS (Netherlands)

    Abhyankar, W.; Beek, A.T.; Dekker, H.; Kort, R.; Brul, S.; Koster, C.G. de

    2011-01-01

    Species from the genus Bacillus have the ability to form endospores, dormant cellular forms that are able to survive heat and acid preservation techniques commonly used in the food industry. Resistance characteristics of spores towards various environmental stresses are in part attributed to their

  6. The Use of Germinants to Potentiate the Sensitivity of Bacillus anthracis Spores to Peracetic Acid.

    Science.gov (United States)

    Celebi, Ozgur; Buyuk, Fatih; Pottage, Tom; Crook, Ant; Hawkey, Suzanna; Cooper, Callum; Bennett, Allan; Sahin, Mitat; Baillie, Leslie

    2016-01-01

    Elimination of Bacillus anthracis spores from the environment is a difficult and costly process due in part to the toxicity of current sporicidal agents. For this reason we investigated the ability of the spore germinants L-alanine (100 mM) and inosine (5 mM) to reduce the concentration of peracetic acid (PAA) required to inactivate B. anthracis spores. While L-alanine significantly enhanced (p = 0.0085) the bactericidal activity of 500 ppm PAA the same was not true for inosine suggesting some form of negative interaction. In contrast the germinant combination proved most effective at 100 ppm PAA (p = 0.0009). To determine if we could achieve similar results in soil we treated soil collected from the burial site of an anthrax infected animal which had been supplemented with spores of the Sterne strain of B. anthracis to increase the level of contamination to 10(4) spores/g. Treatment with germinants followed 1 h later by 5000 ppm PAA eliminated all of the spores. In contrast direct treatment of the animal burial site using this approach delivered using a back pack sprayer had no detectable effect on the level of B. anthracis contamination or on total culturable bacterial numbers over the course of the experiment. It did trigger a significant, but temporary, reduction (p < 0.0001) in the total spore count suggesting that germination had been triggered under real world conditions. In conclusion, we have shown that the application of germinants increase the sensitivity of bacterial spores to PAA. While the results of the single field trial were inconclusive, the study highlighted the potential of this approach and the challenges faced when attempting to perform real world studies on B. anthracis spores contaminated sites.

  7. The use of germinants to potentiate the sensitivity of Bacillus anthracis spores to peracetic acid

    Directory of Open Access Journals (Sweden)

    Ozgur eCelebi

    2016-01-01

    Full Text Available Elimination of Bacillus anthracis spores from the environment is a difficult and costly process due in part to the toxicity of current sporicidal agents. For this reason we investigated the ability of the spore germinants L-alanine (100 mM and inosine (5 mM to reduce the concentration of peracetic acid (PAA required to inactivate B.anthracis spores. While L-alanine significantly enhanced (p=0.0085 the bactericidal activity of 500 ppm PAA the same was not true for inosine suggesting some form of negative interaction. In contrast the germinant combination proved most effective at 100 ppm PAA (p=0.0009. To determine if we could achieve similar results in soil we treated soil collected from the burial site of an anthrax infected animal which had been supplemented with spores of the Sterne strain of B.anthracis to increase the level of contamination to 104 spores/g. Treatment with germinants followed one hour later by 5000 ppm PAA eliminated all of the spores. In contrast direct treatment of the animal burial site using this approach delivered using a back pack sprayer had no detectable effect on the level of B.anthracis contamination or on total culturable bacterial numbers over the course of the experiment. It did trigger a significant, but temporary, reduction (p<0.0001 in the total spore count suggesting that germination had been triggered under real world conditions. In conclusion, we have shown that the application of germinants increase the sensitivity of bacterial spores to PAA. While the results of the single field trial were inconclusive, the study highlighted the potential of this approach and the challenges faced when attempting to perform real world studies on B.anthracis spores contaminated sites.

  8. The immunological characteristics and probiotic function of recombinant Bacillus subtilis spore expressing Clonorchis sinensis cysteine protease.

    Science.gov (United States)

    Tang, Zeli; Shang, Mei; Chen, Tingjin; Ren, Pengli; Sun, Hengchang; Qu, Hongling; Lin, Zhipeng; Zhou, Lina; Yu, Jinyun; Jiang, Hongye; Zhou, Xinyi; Li, Xuerong; Huang, Yan; Xu, Jin; Yu, Xinbing

    2016-12-19

    Clonorchiasis, a food-borne zoonosis, is caused by Clonorchis sinensis. The intestinal tract and bile ducts are crucial places for C. sinensis metacercariae to develop into adult worms. The endospore of Bacillus subtilis is an ideal oral immunization vehicle for delivery of heterologous antigens to intestine. Cysteine protease of C. sinensis (CsCP) is an endogenous key component in the excystment of metacercariae and other physiological or pathological processes. We constructed a fusion gene of CotC (a coat protein)-CsCP and obtained B. subtilis spores with recombinant plasmid of pEB03-CotC-CsCP (B.s-CotC-CsCP). CotC-CsCP expressed on spores' surface was detected by Western blotting and immunofluorescence. Immunological characteristics of recombinant spore coat protein were evaluated in a mouse model. The levels of CsCP-specific antibodies were detected by ELISA. Effects of recombinant spores on mouse intestine were evaluated by histological staining. The activities of biochemical enzymes in serum were assayed by microplate. Liver sections of infected mice were evaluated by Ishak score after Masson's trichrome. The B.s-CotC-CsCP spores displayed CsCP on their coat. Specific IgG and isotypes were significantly induced by coat proteins of B.s-CotC-CsCP spores after subcutaneous immunization. IgA levels in intestinal mucus and bile of B.s-CotC-CsCP orally treated mice significantly increased. Additionally, more IgA-secreting cells were observed in enteraden and lamina propria regions of the mouse jejunum, and an increased amount of acidic mucins in intestines were also observed. There were no significant differences in enzyme levels of serum among groups. No inflammatory injury was observed in the intestinal tissues of each group. The degree of liver fibrosis was significantly reduced after oral immunization with B.s-CotC-CsCP spores. Bacillus subtilis spores maintained the original excellent immunogenicity of CsCP expressed on their surface. Both local and systemic

  9. Protein- protein interaction detection system using fluorescent protein microdomains

    Science.gov (United States)

    Waldo, Geoffrey S.; Cabantous, Stephanie

    2010-02-23

    The invention provides a protein labeling and interaction detection system based on engineered fragments of fluorescent and chromophoric proteins that require fused interacting polypeptides to drive the association of the fragments, and further are soluble and stable, and do not change the solubility of polypeptides to which they are fused. In one embodiment, a test protein X is fused to a sixteen amino acid fragment of GFP (.beta.-strand 10, amino acids 198-214), engineered to not perturb fusion protein solubility. A second test protein Y is fused to a sixteen amino acid fragment of GFP (.beta.-strand 11, amino acids 215-230), engineered to not perturb fusion protein solubility. When X and Y interact, they bring the GFP strands into proximity, and are detected by complementation with a third GFP fragment consisting of GFP amino acids 1-198 (strands 1-9). When GFP strands 10 and 11 are held together by interaction of protein X and Y, they spontaneous association with GFP strands 1-9, resulting in structural complementation, folding, and concomitant GFP fluorescence.

  10. Common structural features of cholesterol binding sites in crystallized soluble proteins.

    Science.gov (United States)

    Bukiya, Anna N; Dopico, Alejandro M

    2017-06-01

    Cholesterol-protein interactions are essential for the architectural organization of cell membranes and for lipid metabolism. While cholesterol-sensing motifs in transmembrane proteins have been identified, little is known about cholesterol recognition by soluble proteins. We reviewed the structural characteristics of binding sites for cholesterol and cholesterol sulfate from crystallographic structures available in the Protein Data Bank. This analysis unveiled key features of cholesterol-binding sites that are present in either all or the majority of sites: i ) the cholesterol molecule is generally positioned between protein domains that have an organized secondary structure; ii ) the cholesterol hydroxyl/sulfo group is often partnered by Asn, Gln, and/or Tyr, while the hydrophobic part of cholesterol interacts with Leu, Ile, Val, and/or Phe; iii ) cholesterol hydrogen-bonding partners are often found on α-helices, while amino acids that interact with cholesterol's hydrophobic core have a slight preference for β-strands and secondary structure-lacking protein areas; iv ) the steroid's C21 and C26 constitute the "hot spots" most often seen for steroid-protein hydrophobic interactions; v ) common "cold spots" are C8-C10, C13, and C17, at which contacts with the proteins were not detected. Several common features we identified for soluble protein-steroid interaction appear evolutionarily conserved. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  11. New insights into structure and function of the different types of fatty acid-binding protein

    NARCIS (Netherlands)

    Zimmerman, Augusta Wilhelmina

    2002-01-01

    Fatty acid binding proteins (FABPs) are small cytosolic proteins with virtually identical backbone structures that facilitate the solubility and intracellular transport of fatty acids. They may also modulate the effect of fatty acids on various metabolic enzymes and receptors and on cellular

  12. Evaluation of citric acid and GDL in the recovery at different pH levels of Clostridium sporogenes PA 3679 spores subjected to HTST treatment conditions.

    Science.gov (United States)

    Silla Santos, M H; Torres Zarzo, J

    1996-04-01

    Spores of Clostridium sporogenes PA 3679 were treated at different temperatures (121, 126, 130 and 135 degrees C) in white asparagus purée (pH 5.8) and acidified with glucono-delta-lactone (GDL) and citric acid to pH levels of 5.5, 5.0 and 4.5. Afterwards, the spores were recovered in MPA3679 medium in various conditions: unacidified (pH 7.5), acidified with GDL (500 ppm) and acidified with citric acid (500 and 250 ppm) to pH levels of 6.5, 6.0 and 5.0. The results indicated that the pH levels, concentration and type of acid used act synergistically rather than independently. Citric acid has a stronger inhibiting effect than GDL on the recovery of C. sporogenes PA 3679 spores. At the higher heat treatments (130 and 135 degrees C) the major injury on the spores sensitize more than against the acids and low pH values.

  13. Contrasting evolutionary patterns of spore coat proteins in two Bacillus species groups are linked to a difference in cellular structure

    Science.gov (United States)

    2013-01-01

    Background The Bacillus subtilis-group and the Bacillus cereus-group are two well-studied groups of species in the genus Bacillus. Bacteria in this genus can produce a highly resistant cell type, the spore, which is encased in a complex protective protein shell called the coat. Spores in the B. cereus-group contain an additional outer layer, the exosporium, which encircles the coat. The coat in B. subtilis spores possesses inner and outer layers. The aim of this study is to investigate whether differences in the spore structures influenced the divergence of the coat protein genes during the evolution of these two Bacillus species groups. Results We designed and implemented a computational framework to compare the evolutionary histories of coat proteins. We curated a list of B. subtilis coat proteins and identified their orthologs in 11 Bacillus species based on phylogenetic congruence. Phylogenetic profiles of these coat proteins show that they can be divided into conserved and labile ones. Coat proteins comprising the B. subtilis inner coat are significantly more conserved than those comprising the outer coat. We then performed genome-wide comparisons of the nonsynonymous/synonymous substitution rate ratio, dN/dS, and found contrasting patterns: Coat proteins have significantly higher dN/dS in the B. subtilis-group genomes, but not in the B. cereus-group genomes. We further corroborated this contrast by examining changes of dN/dS within gene trees, and found that some coat protein gene trees have significantly different dN/dS between the B subtilis-clade and the B. cereus-clade. Conclusions Coat proteins in the B. subtilis- and B. cereus-group species are under contrasting selective pressures. We speculate that the absence of the exosporium in the B. subtilis spore coat effectively lifted a structural constraint that has led to relaxed negative selection pressure on the outer coat. PMID:24283940

  14. The Influence of Sporulation Conditions on the Spore Coat Protein Composition of Bacillus subtilis Spores

    NARCIS (Netherlands)

    Abhyankar, Wishwas R.; Kamphorst, Kiki; Swarge, Bhagyashree N.; van Veen, Henk; van der Wel, Nicole N.; Brul, Stanley; de Koster, Chris G.; de Koning, Leo J.

    2016-01-01

    Spores are of high interest to the food and health sectors because of their extreme resistance to harsh conditions, especially against heat. Earlier research has shown that spores prepared on solid agar plates have a higher heat resistance than those prepared under a liquid medium condition. It has

  15. Two novel heat-soluble protein families abundantly expressed in an anhydrobiotic tardigrade.

    Directory of Open Access Journals (Sweden)

    Ayami Yamaguchi

    Full Text Available Tardigrades are able to tolerate almost complete dehydration by reversibly switching to an ametabolic state. This ability is called anhydrobiosis. In the anhydrobiotic state, tardigrades can withstand various extreme environments including space, but their molecular basis remains largely unknown. Late embryogenesis abundant (LEA proteins are heat-soluble proteins and can prevent protein-aggregation in dehydrated conditions in other anhydrobiotic organisms, but their relevance to tardigrade anhydrobiosis is not clarified. In this study, we focused on the heat-soluble property characteristic of LEA proteins and conducted heat-soluble proteomics using an anhydrobiotic tardigrade. Our heat-soluble proteomics identified five abundant heat-soluble proteins. All of them showed no sequence similarity with LEA proteins and formed two novel protein families with distinct subcellular localizations. We named them Cytoplasmic Abundant Heat Soluble (CAHS and Secretory Abundant Heat Soluble (SAHS protein families, according to their localization. Both protein families were conserved among tardigrades, but not found in other phyla. Although CAHS protein was intrinsically unstructured and SAHS protein was rich in β-structure in the hydrated condition, proteins in both families changed their conformation to an α-helical structure in water-deficient conditions as LEA proteins do. Two conserved repeats of 19-mer motifs in CAHS proteins were capable to form amphiphilic stripes in α-helices, suggesting their roles as molecular shield in water-deficient condition, though charge distribution pattern in α-helices were different between CAHS and LEA proteins. Tardigrades might have evolved novel protein families with a heat-soluble property and this study revealed a novel repertoire of major heat-soluble proteins in these anhydrobiotic animals.

  16. Relationship between Molecular Structure Characteristics of Feed Proteins and Protein In vitro Digestibility and Solubility.

    Science.gov (United States)

    Bai, Mingmei; Qin, Guixin; Sun, Zewei; Long, Guohui

    2016-08-01

    The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller's dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR) spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as α-helices and β-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area) of feed proteins were correlated with their the in vitro digestibility and solubility (p≤0.003); moreover, the relatively quantitative amounts of α-helices, random coils, and α-helix to β-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility (p≤0.004). On the other hand, the percentage of β-sheet structures was negatively correlated with protein in vitro digestibility (pdigestibility at 28 h and solubility. Furthermore, the α-helix-to-β-sheet ratio can be used to predict the nutritional value of feed proteins.

  17. The cellulose-binding activity of the PsB multiprotein complex is required for proper assembly of the spore coat and spore viability in Dictyostelium discoideum.

    Science.gov (United States)

    Srinivasan, S; Griffiths, K R; McGuire, V; Champion, A; Williams, K L; Alexander, S

    2000-08-01

    The terminal event of spore differentiation in the cellular slime mould Dictyostelium discoideum is the assembly of the spore coat, which surrounds the dormant amoeba and allows the organism to survive during extended periods of environmental stress. The spore coat is a polarized extracellular matrix composed of glycoproteins and cellulose. The process of spore coat formation begins by the regulated secretion of spore coat proteins from the prespore vesicles (PSVs). Four of the major spore coat proteins (SP96, PsB/SP85, SP70 and SP60) exist as a preassembled multiprotein complex within the PSVs. This complete complex has an endogenous cellulose-binding activity. Mutant strains lacking either the SP96 or SP70 proteins produce partial complexes that do not have cellulose-binding activity, while mutants lacking SP60 produce a partial complex that retains this activity. Using a combination of immunofluorescence microscopy and biochemical methods we now show that the lack of cellulose-binding activity in the SP96 and SP70 mutants results in abnormally assembled spore coats and spores with greatly reduced viability. In contrast, the SP60 mutant, in which the PsB complex retains its cellulose-binding activity, produces spores with apparently unaltered structure and viability. Thus, it is the loss of the cellulose-binding activity of the PsB complex, rather than the mere loss of individual spore coat proteins, that results in compromised spore coat structure. These results support the idea that the cellulose-binding activity associated with the complete PsB complex plays an active role in the assembly of the spore coat.

  18. Hyphal Growth from Spores of the Mycorrhizal Fungus Glomus Caledonius: Effect of Amino Acids

    DEFF Research Database (Denmark)

    Hepper, C.M.; Jakobsen, Iver

    1983-01-01

    Hyphal growth from spores of Glomus caledonius (Nicol. and Gerd.) Trappe and Gerdemann was stimulated by cystine, glycine and lysine at optimum concentrations of 4.6, 556 and 825 mg l−1 respectively. When all three amino acids were supplied together in water agar, five times more growth...

  19. Facilitating protein solubility by use of peptide extensions

    Science.gov (United States)

    Freimuth, Paul I; Zhang, Yian-Biao; Howitt, Jason

    2013-09-17

    Expression vectors for expression of a protein or polypeptide of interest as a fusion product composed of the protein or polypeptide of interest fused at one terminus to a solubility enhancing peptide extension are provided. Sequences encoding the peptide extensions are provided. The invention further comprises antibodies which bind specifically to one or more of the solubility enhancing peptide extensions.

  20. Expression and characterization of a novel spore wall protein from ...

    African Journals Online (AJOL)

    Microsporidia are obligate intracellular, eukaryotic, spore-forming parasites. The environmentally resistant spores, which harbor a rigid cell wall, are critical for their survival outside their host cells and host-to-host transmission. The spore wall comprises two major layers: the exospore and the endospore. In Nosema ...

  1. Development of Spore Protein of Myxobolus koi as an Immunostimulant for Prevent of Myxobolusis on Gold Fish (Cyprinus carpio Linn) by Oral Immunisation

    Science.gov (United States)

    Mahasri, Gunanti

    2017-02-01

    Production of Gold fish (Cyprinus carpio Linn) in Indonesia has always increased from 2013 to 2015 year by year with increasing average 2% per year. The amount of production was respectively 571.892 tonnes, 1129.273 tonnes, and 1186.674 tonnes. There were almost no problems to sale of gold fish because it had a good enough prospect. The aims of this research were Isolation of spore protein of Myxobolus koi by using SDS-PAGE to analyze immun respons and survival rate gold fish that immunized with spore protein of Myxobolus koi. The method of this research used experimental method, and belonged to 4 treatments that are: Controle = the group of gold fish not immunized with protein spore of Myxobolus koi neither infected by Myxobolus koi (T1). The group immunized and infested by spore of Myxobolus koi (T2), The group which immunized and not infested by Myxobolus koi (T3), and The group only infested by Myxobolus koi (T4). The dose of immunostimulant was 5 ml in 1 kg of food. The result showed that there were two bands of whole spore protein with molecule weight (MW) 150 kDa and 72 kDa and one band of crude protein Myxobolus koi with molecule weight 73 kD and the optical density point was 0.132 on the first day and increased to 0.769 on the 56 th day. The result also showed that the immun respons and survival rate increased from 27% to 86% in chellence test. The protein spore of Myxobolus koi can used to develops material for immunostimulant and to prevent the myxobolusis.

  2. One of the Two Genes Encoding Nucleoid-Associated HU Proteins in Streptomyces coelicolor Is Developmentally Regulated and Specifically Involved in Spore Maturation▿ †

    Science.gov (United States)

    Salerno, Paola; Larsson, Jessica; Bucca, Giselda; Laing, Emma; Smith, Colin P.; Flärdh, Klas

    2009-01-01

    Streptomyces genomes encode two homologs of the nucleoid-associated HU proteins. One of them, here designated HupA, is of a conventional type similar to E. coli HUα and HUβ, while the other, HupS, is a two-domain protein. In addition to the N-terminal part that is similar to that of HU proteins, it has a C-terminal domain that is similar to the alanine- and lysine-rich C termini of eukaryotic linker histones. Such two-domain HU proteins are found only among Actinobacteria. In this phylum some organisms have only a single HU protein of the type with a C-terminal histone H1-like domain (e.g., Hlp in Mycobacterium smegmatis), while others have only a single conventional HU. Yet others, including the streptomycetes, produce both types of HU proteins. We show here that the two HU genes in Streptomyces coelicolor are differentially regulated and that hupS is specifically expressed during sporulation, while hupA is expressed in vegetative hyphae. The developmental upregulation of hupS occurred in sporogenic aerial hyphal compartments and was dependent on the developmental regulators whiA, whiG, and whiI. HupS was found to be nucleoid associated in spores, and a hupS deletion mutant had an average nucleoid size in spores larger than that in the parent strain. The mutant spores were also defective in heat resistance and spore pigmentation, although they possessed apparently normal spore walls and displayed no increased sensitivity to detergents. Overall, the results show that HupS is specifically involved in sporulation and may affect nucleoid architecture and protection in spores of S. coelicolor. PMID:19717607

  3. A review of machine learning methods to predict the solubility of overexpressed recombinant proteins in Escherichia coli.

    Science.gov (United States)

    Habibi, Narjeskhatoon; Mohd Hashim, Siti Z; Norouzi, Alireza; Samian, Mohammed Razip

    2014-05-08

    Over the last 20 years in biotechnology, the production of recombinant proteins has been a crucial bioprocess in both biopharmaceutical and research arena in terms of human health, scientific impact and economic volume. Although logical strategies of genetic engineering have been established, protein overexpression is still an art. In particular, heterologous expression is often hindered by low level of production and frequent fail due to opaque reasons. The problem is accentuated because there is no generic solution available to enhance heterologous overexpression. For a given protein, the extent of its solubility can indicate the quality of its function. Over 30% of synthesized proteins are not soluble. In certain experimental circumstances, including temperature, expression host, etc., protein solubility is a feature eventually defined by its sequence. Until now, numerous methods based on machine learning are proposed to predict the solubility of protein merely from its amino acid sequence. In spite of the 20 years of research on the matter, no comprehensive review is available on the published methods. This paper presents an extensive review of the existing models to predict protein solubility in Escherichia coli recombinant protein overexpression system. The models are investigated and compared regarding the datasets used, features, feature selection methods, machine learning techniques and accuracy of prediction. A discussion on the models is provided at the end. This study aims to investigate extensively the machine learning based methods to predict recombinant protein solubility, so as to offer a general as well as a detailed understanding for researches in the field. Some of the models present acceptable prediction performances and convenient user interfaces. These models can be considered as valuable tools to predict recombinant protein overexpression results before performing real laboratory experiments, thus saving labour, time and cost.

  4. EFFECT OF HEAT TREATMENT ON SOYBEAN PROTEIN SOLUBILITY

    Directory of Open Access Journals (Sweden)

    RODICA CĂPRIŢĂ

    2007-05-01

    Full Text Available The use of soybean products in animal feeds is limited due to the presence of antinutritional factors (ANF. Proper heat processing is required to destroy ANF naturally present in raw soybeans and to remove solvent remaining from the oil extraction process. Over and under toasting of soybean causes lower nutritional value. Excessive heat treatment causes Maillard reaction which affects the availability of lysine in particular and produces changes to the chemical structure of proteins resulting in a decrease of the nutritive value. The objective of this study was to evaluate the effect of heating time on the protein solubility. The investigation of the heating time on protein solubility in soybean meal (SBM revealed a negative correlation (r = -0.9596. Since the urease index is suitable only for detecting under processed SBM, the protein solubility is an important index for monitoring SBM quality.

  5. Self assembling nanocomposites for protein delivery: supramolecular interactions of soluble polymers with protein drugs.

    Science.gov (United States)

    Salmaso, Stefano; Caliceti, Paolo

    2013-01-02

    Translation of therapeutic proteins to pharmaceutical products is often encumbered by their inadequate physicochemical and biopharmaceutical properties, namely low stability and poor bioavailability. Over the last decades, several academic and industrial research programs have been focused on development of biocompatible polymers to produce appropriate formulations that provide for enhanced therapeutic performance. According to their physicochemical properties, polymers have been exploited to obtain a variety of formulations including biodegradable microparticles, 3-dimensional hydrogels, bioconjugates and soluble nanocomposites. Several soluble polymers bearing charges or hydrophobic moieties along the macromolecular backbone have been found to physically associate with proteins to form soluble nanocomplexes. Physical complexation is deemed a valuable alternative tool to the chemical bioconjugation. Soluble protein/polymer nanocomplexes formed by physical specific or unspecific interactions have been found in fact to possess peculiar physicochemical, and biopharmaceutical properties. Accordingly, soluble polymeric systems have been developed to increase the protein stability, enhance the bioavailability, promote the absorption across the biological barriers, and prolong the protein residence in the bloodstream. Furthermore, a few polymers have been found to favour the protein internalisation into cells or boost their immunogenic potential by acting as immunoadjuvant in vaccination protocols. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Membrane Proteins Are Dramatically Less Conserved than Water-Soluble Proteins across the Tree of Life.

    Science.gov (United States)

    Sojo, Victor; Dessimoz, Christophe; Pomiankowski, Andrew; Lane, Nick

    2016-11-01

    Membrane proteins are crucial in transport, signaling, bioenergetics, catalysis, and as drug targets. Here, we show that membrane proteins have dramatically fewer detectable orthologs than water-soluble proteins, less than half in most species analyzed. This sparse distribution could reflect rapid divergence or gene loss. We find that both mechanisms operate. First, membrane proteins evolve faster than water-soluble proteins, particularly in their exterior-facing portions. Second, we demonstrate that predicted ancestral membrane proteins are preferentially lost compared with water-soluble proteins in closely related species of archaea and bacteria. These patterns are consistent across the whole tree of life, and in each of the three domains of archaea, bacteria, and eukaryotes. Our findings point to a fundamental evolutionary principle: membrane proteins evolve faster due to stronger adaptive selection in changing environments, whereas cytosolic proteins are under more stringent purifying selection in the homeostatic interior of the cell. This effect should be strongest in prokaryotes, weaker in unicellular eukaryotes (with intracellular membranes), and weakest in multicellular eukaryotes (with extracellular homeostasis). We demonstrate that this is indeed the case. Similarly, we show that extracellular water-soluble proteins exhibit an even stronger pattern of low homology than membrane proteins. These striking differences in conservation of membrane proteins versus water-soluble proteins have important implications for evolution and medicine. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  7. Decontamination of materials contaminated with Bacillus anthracis and Bacillus thuringiensis Al Hakam spores using PES-Solid, a solid source of peracetic acid.

    Science.gov (United States)

    Buhr, T L; Wells, C M; Young, A A; Minter, Z A; Johnson, C A; Payne, A N; McPherson, D C

    2013-08-01

    To develop test methods and evaluate survival of Bacillus anthracis Ames, B. anthracis ∆Sterne and B. thuringiensis Al Hakam spores after exposure to PES-Solid (a solid source of peracetic acid), including PES-Solid formulations with bacteriostatic surfactants. Spores (≥ 7 logs) were dried on seven different test materials and treated with three different PES-Solid formulations (or preneutralized controls) at room temperature for 15 min. There was either no spore survival or less than 1 log (<10 spores) of spore survival in 56 of 63 test combinations (strain, formulation and substrate). Less than 2.7 logs (<180 spores) survived in the remaining seven test combinations. The highest spore survival rates were seen on water-dispersible chemical agent resistant coating (CARC-W) and Naval ship topcoat (NTC). Electron microscopy and Coulter analysis showed that all spore structures were intact after spore inactivation with PES-Solid. Three PES-Solid formulations inactivated Bacillus spores that were dried on seven different materials. A test method was developed to show that PES-Solid formulations effectively inactivate Bacillus spores on different materials. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  8. Solubilities of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures

    International Nuclear Information System (INIS)

    Wang, Hui; Wang, Qinbo; Xiong, Zhenhua; Chen, Chuxiong; Shen, Binwei

    2015-01-01

    Highlights: • Solubilities of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were measured at 1 atm. • The experimental temperature ranges at (298.35 to 355.65) K. • Effects of benzyl alcohol mass concentration at (0.00 to 1.00) on the solubilities of benzoic acid were studied. • The experimental data were correlated with NRTL model. • Thermodynamic functions of dissolution of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were discussed. - Abstract: The solubility of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures was measured at temperature from (298.35 to 355.65) K and atmospheric pressure. The measured solubility increases with the increasing temperature at constant solvent composition. The effects of mass fraction benzaldehyde in the solvent mixtures at (0.0 to 1.00) on the solubility were studied. The measured solubility decreases with the increasing mass fraction of benzaldehyde. The experimental results were correlated with the non-random two-liquid (NRTL) equations, and good agreement between the correlated and the experimental values was obtained. Thermodynamic functions for the solution of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures were calculated with the van’t Hoff plot. The apparent dissolution Gibbs free energy change was also calculated

  9. Poly(aspartic acid) with adjustable pH-dependent solubility.

    Science.gov (United States)

    Németh, Csaba; Gyarmati, Benjámin; Abdullin, Timur; László, Krisztina; Szilágyi, András

    2017-02-01

    Poly(aspartic acid) (PASP) derivatives with adjustable pH-dependent solubility were synthesized and characterized to establish the relationship between their structure and solubility in order to predict their applicability as a basic material for enteric coatings. Polysuccinimide, the precursor of PASP, was modified with short chain alkylamines, and the residual succinimide rings were subsequently opened to prepare the corresponding PASP derivatives. Study of the effect of the type and concentration of the side groups on the pH-dependent solubility of PASP showed that solubility can be adjusted by proper selection of the chemical structure. The Henderson-Hasselbalch (HH) and the extended HH equations were used to describe the pH-dependent solubility of the polymers quantitatively. The estimate provided by the HH equation is poor, but an accurate description of the pH-dependent solubility can be found with the extended HH equation. The dissolution rate of a polymer film prepared from a selected PASP derivative was determined by fluorescence marking. The film dissolved rapidly when the pH was increased above its pK a . Cellular viability tests show that PASP derivatives are non-toxic to a human cell line. These polymers are thus of great interest as starting materials for enteric coatings. Poly(amino acid) type biocompatible polymers were synthesized for future use as pharmaceutical film coatings. To this end, we tailored the pH-dependent solubility of poly(aspartic acid) (PASP). It was found that both the solubility and the pK a values of the modified PASP depended strongly on composition. Fluorescent marking was used to characterize the dissolution of a chosen PASP derivative. In acidic media only a negligible amount of the polymer dissolved, but dissolution was very fast and complete at the pH values that prevail in the small intestine. As a consequence, enteric coatings based on such PASP derivatives may be used for drug delivery in the gastrointestinal tract

  10. Soluble arabinoxylan alters digesta flow and protein digestion of red meat-containing diets in pigs.

    Science.gov (United States)

    Zhang, Dagong; Williams, Barbara A; Mikkelsen, Deirdre; Li, Xiuhua; Keates, Helen L; Lisle, Allan T; Collins, Helen M; Fincher, Geoffrey B; Bird, Anthony R; Topping, David L; Gidley, Michael J; Bryden, Wayne L

    2015-09-01

    The aim of this study was to investigate how a moderate increase in dietary meat content combined (or not) with soluble fibre would influence protein digestion as well as digesta characteristics and flow. Four groups of pigs were fed Western-style diets (high-protein/high-fat) containing two types of barbecued red meat, one with and one without a wheat arabinoxylan-rich fraction. After 4 wk, digesta samples were collected from small and large intestinal sites and analyzed for protein, amino acids, dry matter, and acid-insoluble ash. Tissue samples were also collected from each site. Arabinoxylan consumption led to somewhat lower apparent protein digestibility within the small and large intestines as well as shorter mean retention times. This suggests that the lowered protein digestibility is due, at least partly, to shorter access time to digestive proteases and absorptive surfaces. Additionally, digesta mass was higher in pigs fed arabinoxylan while dry matter (%) was lower, indicating an increased digesta water-holding capacity due to the presence of a soluble dietary fiber. Data showed that solubilized wheat arabinoxylan provides potential health benefits through decreased protein digestibility, increased digesta mass, and reduced mean retention time, even for diets with a moderately higher protein content. These factors are associated with efficiency of digestion and satiety, both of which have implications for prevention of obesity and other health disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Proteomic Analysis of Bacillus cereus Spores

    National Research Council Canada - National Science Library

    Schwandt, Kerrie

    2002-01-01

    .... All of the identified proteins were plausible spore components, and included chaperonins, sporulation regulators, ribosomal proteins, proteases, and metabolic enzymes involved in energy production...

  12. Breaking the spores of Ganoderma lucidum by fermentation with ...

    African Journals Online (AJOL)

    In this paper, fermentation of G. lucidum with Lactobacillus plantarum was applied to break down the sporoderm. Scanning electron microscope (SEM) was used to characterize the spores. The broken spores were found on the 3rd day and complete breaking on the 5th day of fermentation. Lactic acid, acetic acid and ...

  13. Protein solubility and folding enhancement by interaction with RNA.

    Directory of Open Access Journals (Sweden)

    Seong Il Choi

    Full Text Available While basic mechanisms of several major molecular chaperones are well understood, this machinery has been known to be involved in folding of only limited number of proteins inside the cells. Here, we report a chaperone type of protein folding facilitated by interaction with RNA. When an RNA-binding module is placed at the N-terminus of aggregation-prone target proteins, this module, upon binding with RNA, further promotes the solubility of passenger proteins, potentially leading to enhancement of proper protein folding. Studies on in vitro refolding in the presence of RNA, coexpression of RNA molecules in vivo and the mutants with impaired RNA binding ability suggests that RNA can exert chaperoning effect on their bound proteins. The results suggest that RNA binding could affect the overall kinetic network of protein folding pathway in favor of productive folding over off-pathway aggregation. In addition, the RNA binding-mediated solubility enhancement is extremely robust for increasing soluble yield of passenger proteins and could be usefully implemented for high-throughput protein expression for functional and structural genomic research initiatives. The RNA-mediated chaperone type presented here would give new insights into de novo folding in vivo.

  14. Atomic force microscopy imaging and single molecule recognition force spectroscopy of coat proteins on the surface of Bacillus subtilis spore.

    Science.gov (United States)

    Tang, Jilin; Krajcikova, Daniela; Zhu, Rong; Ebner, Andreas; Cutting, Simon; Gruber, Hermann J; Barak, Imrich; Hinterdorfer, Peter

    2007-01-01

    Coat assembly in Bacillus subtilis serves as a tractable model for the study of the self-assembly process of biological structures and has a significant potential for use in nano-biotechnological applications. In the present study, the morphology of B. subtilis spores was investigated by magnetically driven dynamic force microscopy (MAC mode atomic force microscopy) under physiological conditions. B. subtilis spores appeared as prolate structures, with a length of 0.6-3 microm and a width of about 0.5-2 microm. The spore surface was mainly covered with bump-like structures with diameters ranging from 8 to 70 nm. Besides topographical explorations, single molecule recognition force spectroscopy (SMRFS) was used to characterize the spore coat protein CotA. This protein was specifically recognized by a polyclonal antibody directed against CotA (anti-CotA), the antibody being covalently tethered to the AFM tip via a polyethylene glycol linker. The unbinding force between CotA and anti-CotA was determined as 55 +/- 2 pN. From the high-binding probability of more than 20% in force-distance cycles it is concluded that CotA locates in the outer surface of B. subtilis spores. Copyright (c) 2007 John Wiley & Sons, Ltd.

  15. Solubility of salicylic acid in pure alcohols at different temperatures

    International Nuclear Information System (INIS)

    Lim, Junhyuk; Jang, Sunghyun; Cho, Hye Kyoung; Shin, Moon Sam; Kim, Hwayong

    2013-01-01

    Highlights: ► Solubility data of salicylic acid in pure alkanols were measured. ► The experimental data were correlated with NRTL, UNIQUAC and Wilson models. ► The data are fit well with all three models for the six pure alcohols studied. ► Adjustable interaction parameters were suggested. - Abstract: This work focused on the experimental measurements and the numerical calculations of the solubility of salicylic acid in various alcohols. The solubility of salicylic acid in pure alcohols was determined using a (solid + liquid) equilibrium measurement apparatus at temperatures ranging from (278.15 to 318.15) K. Also, the melting temperature and fusion enthalpy of salicylic acid were determined by a differential scanning calorimeter (TA instrument Q100). The experimental results were correlated with the equation for solubility of a solid in a liquid with the nonrandom two liquid (NRTL), universal quasi-chemical (UNIQUAC) and Wilson models for liquid phase activity coefficients to validate the quality of the data taken. Adjustable interaction parameters were also provided. The experimental data fit appropriately with all three models for the pure alcohols studied.

  16. Adsorption of β-galactosidase of Alicyclobacillus acidocaldarius on wild type and mutants spores of Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Sirec Teja

    2012-08-01

    Full Text Available Abstract Background The Bacillus subtilis spore has long been used as a surface display system with potential applications in a variety of fields ranging from mucosal vaccine delivery, bioremediation and biocatalyst development. More recently, a non-recombinant approach of spore display has been proposed and heterologous proteins adsorbed on the spore surface. We used the well-characterized β-galactosidase from the thermoacidophilic bacterium Alicyclobacillus acidocaldarius as a model to study enzyme adsorption, to analyze whether and how spore-adsorption affects the properties of the enzyme and to improve the efficiency of the process. Results We report that purified β-galactosidase molecules were adsorbed to purified spores of a wild type strain of B. subtilis retaining ca. 50% of their enzymatic activity. Optimal pH and temperature of the enzyme were not altered by the presence of the spore, that protected the adsorbed β-galactosidase from exposure to acidic pH conditions. A collection of mutant strains of B. subtilis lacking a single or several spore coat proteins was compared to the isogenic parental strain for the adsorption efficiency. Mutants with an altered outermost spore layer (crust were able to adsorb 60-80% of the enzyme, while mutants with a severely altered or totally lacking outer coat adsorbed 100% of the β-galactosidase molecules present in the adsorption reaction. Conclusion Our results indicate that the spore surface structures, the crust and the outer coat layer, have an negative effect on the adhesion of the β-galactosidase. Electrostatic forces, previously suggested as main determinants of spore adsorption, do not seem to play an essential role in the spore-β-galactosidase interaction. The analysis of mutants with altered spore surface has shown that the process of spore adsorption can be improved and has suggested that such improvement has to be based on a better understanding of the spore surface structure

  17. Production of a water-soluble fertilizer containing amino acids by solid-state fermentation of soybean meal and evaluation of its efficacy on the rapeseed growth.

    Science.gov (United States)

    Wang, Jianlei; Liu, Zhemin; Wang, Yue; Cheng, Wen; Mou, Haijin

    2014-10-10

    Soybean meal is a by-product of soybean oil extraction and contains approximately 44% protein. We performed solid-state fermentation by using Bacillus subtilis strain N-2 to produce a water-soluble fertilizer containing amino acids. Strain N-2 produced a high yield of protease, which transformed the proteins in soybean meal into peptide and free amino acids that were dissolved in the fermentation products. Based on the Plackett-Burman design, the initial pH of the fermentation substrate, number of days of fermentation, and the ratio of liquid to soybean meal exhibited significant effects on the recovery of proteins in the resulting water-soluble solution. According to the predicted results of the central composite design, the highest recovery of soluble proteins (99.072%) was achieved at the optimum conditions. Under these conditions, the resulting solution contained 50.42% small peptides and 7.9% poly-γ-glutamic acid (γ-PGA). The water-soluble fertilizer robustly increased the activity of the rapeseed root system, chlorophyll content, leaf area, shoot dry weight, root length, and root weight at a concentration of 0.25% (w/v). This methodology offers a value-added use of soybean meal. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Characterization of Acid Soluble Collagen from Redbelly Yellowtail Fusilier Fish Skin (Caesio cuning

    Directory of Open Access Journals (Sweden)

    Ika Astiana

    2016-04-01

    Full Text Available Fish skin can be used as raw material for producing collagen. The collagen can be extracted by chemicalor combination of chemical and enzymatic processes. Extraction of collagen chemically can do with theacid process that produces acid soluble collagen (ASC. This study aimed to determine the optimumconcentration and time of pretreatment and extraction, also to determine the characteristics of the acidsoluble collagen from the skin of yellow tail fish. Extraction of collagen done by pretreatment using NaOH atthe concentration of 0.05; 0.1; and 0.15 M and extraction using acetic acid at the concentration of 0.3; 0.5; and0.7 M. Pretreatment NaOH with concentration 0.05 M and soaking time of 8 hours is the best combinationfor eliminating non collagen protein. Combination treatment of acetic acid at the concentration of 0.3 Mfor 3 days obtained the best solubility. The yield of collagen ASC was 18.4±1.49% (db and 5.79±0.47%(wb. Amino acid composition that is dominant in the ASC collagen was glycine (25.09±0.003%, alanine(13.71±0.075%, and proline (12.15±0.132%. Collagen from yellow tail fish skin has α1, α2, β and γprotein structure with the molecular weight of 125, 113, 170-181, and 208 KDa. The transition and meltingtemperatures of collagen were 67.69oC and 144.4oC. The surface structure of collagen by analysis of SEM hasfibers on the surface.Keywords: cholesterol, fatty acids, meat tissue, proximate, red snapper (L. argentimaculatus

  19. Structure-property relationships in halogenbenzoic acids: Thermodynamics of sublimation, fusion, vaporization and solubility.

    Science.gov (United States)

    Zherikova, Kseniya V; Svetlov, Aleksey A; Kuratieva, Natalia V; Verevkin, Sergey P

    2016-10-01

    Temperature dependences of vapor pressures for 2-, 3-, and 4-bromobenzoic acid, as well as for five isomeric bromo-methylbenzoic acids were studied by the transpiration method. Melting temperatures and enthalpies of fusion for all isomeric bromo-methylbenzoic acids and 4-bromobenzoic acid were measured with a DSC. The molar enthalpies of sublimation and vaporization were derived. These data together with results available in the literature were collected and checked for internal consistency using a group-additivity procedure and results from X-ray structural diffraction studies. Specific (hydrogen bonding) interactions in the liquid and in the crystal phase of halogenbenzoic acids were quantified based on experimental values of vaporization and sublimation enthalpies. Structure-property correlations of solubilities of halogenobenzoic acids with sublimation pressures and sublimation enthalpies were developed and solubilities of bromo-benzoic acids were estimated. These new results resolve much of the ambiguity in the available thermochemical and solubility data on bromobenzoic acids. The approach based on structure property correlations can be applied for the assessment of water solubility of sparingly soluble drugs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Role of the gerA operon in L-alanine germination of Bacillus licheniformis spores

    Directory of Open Access Journals (Sweden)

    Løvdal Irene S

    2012-03-01

    Full Text Available Abstract Background The genome of Bacillus licheniformis DSM 13 harbours three neighbouring open reading frames showing protein sequence similarities to the proteins encoded from the Bacillus subtilis subsp. subtilis 168 gerA operon, GerAA, GerAB and GerAC. In B. subtilis, these proteins are assumed to form a germinant receptor involved in spore germination induced by the amino acid L-alanine. Results In this study we show that disruption of the gerAA gene in B. licheniformis MW3 hamper L-alanine and casein hydrolysate-triggered spore germination, measured by absorbance at 600 nm and confirmed by phase contrast microscopy. This ability was restored by complementation with a plasmid-borne copy of the gerA locus. Addition of D-alanine in the casein hydrolysate germination assay abolished germination of both B. licheniformis MW3 and the complementation mutant. Germination of both B. licheniformis MW3 and the gerA disruption mutant was induced by the non-nutrient germinant Ca2+-Dipicolinic acid. Conclusions These results demonstrate that the B. licheniformis MW3 gerA locus is involved in germination induced by L-alanine and potentially other components present in casein hydrolysate.

  1. Role of the gerA operon in L-alanine germination of Bacillus licheniformis spores

    Science.gov (United States)

    2012-01-01

    Background The genome of Bacillus licheniformis DSM 13 harbours three neighbouring open reading frames showing protein sequence similarities to the proteins encoded from the Bacillus subtilis subsp. subtilis 168 gerA operon, GerAA, GerAB and GerAC. In B. subtilis, these proteins are assumed to form a germinant receptor involved in spore germination induced by the amino acid L-alanine. Results In this study we show that disruption of the gerAA gene in B. licheniformis MW3 hamper L-alanine and casein hydrolysate-triggered spore germination, measured by absorbance at 600 nm and confirmed by phase contrast microscopy. This ability was restored by complementation with a plasmid-borne copy of the gerA locus. Addition of D-alanine in the casein hydrolysate germination assay abolished germination of both B. licheniformis MW3 and the complementation mutant. Germination of both B. licheniformis MW3 and the gerA disruption mutant was induced by the non-nutrient germinant Ca2+-Dipicolinic acid. Conclusions These results demonstrate that the B. licheniformis MW3 gerA locus is involved in germination induced by L-alanine and potentially other components present in casein hydrolysate. PMID:22420404

  2. [Distribution and spatial ordering of biopolymer molecules in resting bacterial spores].

    Science.gov (United States)

    Duda, V I; Korolev, Iu N; El'-Registan, G I; Duzha, M V; Telegin, N L

    1978-01-01

    The presence, distribution and spatial arrangement of biopolymers in situ were studied in both a total intact spore and in a certain cellular layer using a spectroscopic technique of attenuated total refraction (ATR-IR) in the IR region. In contrast to vegetative cells, intact spores were characterized by isotropic distribution of protein components. This feature can be regarded as an index of the cryptobiotic state of spores. However, the distribution of protein components among individual layers of a spore was anisotropic. Bonds characterized by amide I and amide II bands were most often ordered in a layer which comprised cellular structures from the exosporium to the inner spore membrane.

  3. Elastic and inelastic light scattering from single bacterial spores in an optical trap allows the monitoring of spore germination dynamics

    OpenAIRE

    Peng, Lixin; Chen, De; Setlow, Peter; Li, Yong-qing

    2009-01-01

    Raman scattering spectroscopy and elastic light scattering intensity (ESLI) were used to simultaneously measure levels of Ca-dipicolinic acid (CaDPA) and changes in spore morphology and refractive index during germination of individual B. subtilis spores with and without the two redundant enzymes (CLEs), CwlJ and SleB, that degrade spores’ peptidoglycan cortex. Conclusions from these measurements include: 1) CaDPA release from individual wild-type germinating spores was biphasic; in a first h...

  4. INCREASING NUTRITIONAL CONTENT OF ARTIFICIAL FEED WITH WHOLE SPORE PROTEIN OF MYXOBOLUS KOI AS AN IMMUNOSTIMULTANT ON GOLDFISH (CYPRINUS CARPIO L.

    Directory of Open Access Journals (Sweden)

    Qusairi A.

    2018-02-01

    Full Text Available The production of goldfish in Indonesia in 2010-2013 has increased by 7.09%, the lowest average production increase compared with other main commodities such as shrimp, tilapia, catfish, and others. One of the primary causes of the low increase in production is the presence of disease and high price of feed in some central goldfish productions. The purpose of this study was to analyze the effect of whole spore protein of Myxobolus koi on goldfish (Cyprinus carpio L. through feed to immune response, growth rate, feed efficiency and survival rate. This research was conducted with complete randomized design with 5 replications. This study used two types of treatment, control (100% artificial feed and artificial feed + immunostimulant (whole spore protein of Myxobolus koi + Boster® Progol adhesive spores. The results showed that whole spore protein of Myxobolus koi given to the feed as immunostimulant can cause response of the immune through the increase of monocytes and lymphocytes in white blood cells on days 7, 14 and 28 observations, daily growth rate of 5.55% compared without immunostimulant with the rate of 1.13%; feed efficiency of 36.57% compared with no immunostimulant, which is only 23.84%, and the treatment gives a 99% survival rate.

  5. Density, viscosity, and N2O solubility of aqueous amino acid salt and amine amino acid salt solutions

    International Nuclear Information System (INIS)

    Aronu, Ugochukwu E.; Hartono, Ardi; Svendsen, Hallvard F.

    2012-01-01

    Highlights: ► Density of amino acid salt and amine amino acid salt. ► Viscosity of amino acid salt and amine amino acid salt. ► Henry’s law constant/N 2 O solubility of amino acid salt and amine amino acid salt. ► Schumpe model. Correlations for density, viscosity, and N 2 O solubility. - Abstract: Physicochemical properties of aqueous amino acid salt (AAS), potassium salt of sarcosine (KSAR) and aqueous amine amino acid salt (AAAS), 3-(methylamino)propylamine/sarcosine (SARMAPA) have been studied. Densities of KSAR were measured for sarcosine mole fraction 0.02 to 0.25 for temperature range 298.15 K to 353.15 K, the viscosities were measured for 0.02 to 0.10 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.10 mole fraction sarcosine solutions (298.15 K to 363.15 K). Densities of SARMAPA were measured for sarcosine mole fraction 0.02 to 0.23 for temperature range (298.15 K to 353.15 K), viscosities were measured for 0.02 to 0.16 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.16 mole fraction sarcosine solutions (298.15 K to 343.15 K). Experimental results were correlated well with empirical correlations and N 2 O solubility results for KSAR were predicted adequately by a Schumpe model. The solubilities of N 2 O in AAS and AAAS are significantly lower than values for amines. The solubilities vary as: amine > AAAS > AAS.

  6. How to find soluble proteins: a comprehensive analysis of alpha/beta hydrolases for recombinant expression in E. coli

    Directory of Open Access Journals (Sweden)

    Barth Sandra

    2005-04-01

    Full Text Available Abstract Background In screening of libraries derived by expression cloning, expression of active proteins in E. coli can be limited by formation of inclusion bodies. In these cases it would be desirable to enrich gene libraries for coding sequences with soluble gene products in E. coli and thus to improve the efficiency of screening. Previously Wilkinson and Harrison showed that solubility can be predicted from amino acid composition (Biotechnology 1991, 9(5:443–448. We have applied this analysis to members of the alpha/beta hydrolase fold family to predict their solubility in E. coli. alpha/beta hydrolases are a highly diverse family with more than 1800 proteins which have been grouped into homologous families and superfamilies. Results The predicted solubility in E. coli depends on hydrolase size, phylogenetic origin of the host organism, the homologous family and the superfamily, to which the hydrolase belongs. In general small hydrolases are predicted to be more soluble than large hydrolases, and eukaryotic hydrolases are predicted to be less soluble in E. coli than prokaryotic ones. However, combining phylogenetic origin and size leads to more complex conclusions. Hydrolases from prokaryotic, fungal and metazoan origin are predicted to be most soluble if they are of small, medium and large size, respectively. We observed large variations of predicted solubility between hydrolases from different homologous families and from different taxa. Conclusion A comprehensive analysis of all alpha/beta hydrolase sequences allows more efficient screenings for new soluble alpha/beta hydrolases by the use of libraries which contain more soluble gene products. Screening of hydrolases from families whose members are hard to express as soluble proteins in E. coli should first be done in coding sequences of organisms from phylogenetic groups with the highest average of predicted solubility for proteins of this family. The tools developed here can be used

  7. Properties of whey protein isolates extruded under acidic and alkaline conditions.

    Science.gov (United States)

    Onwulata, C I; Isobe, S; Tomasula, P M; Cooke, P H

    2006-01-01

    Whey proteins have wide acceptance and use in many products due to their beneficial nutritional properties. To further increase the amount of whey protein isolates (WPI) that may be added to products such as extruded snacks and meats, texturization of WPI is necessary. Texturization changes the folding of globular proteins to improve interaction with other ingredients and create new functional ingredients. In this study, WPI pastes (60% solids) were extruded in a twin-screw extruder at 100 degrees C with 4 pH-adjusted water streams: acidic (pH 2.0 +/- 0.2) and alkaline (pH 12.4 +/- 0.4) streams from 2 N HCl and 2 N NaOH, respectively, and acidic (pH 2.5 +/- 0.2) and alkaline (pH 11.5 +/- 0.4) electrolyzed water streams; these were compared with WPI extruded with deionized water. The effects of water acidity on WPI solubility at pH 7, color, microstructure, Rapid Visco Analyzer pasting properties, and physical structure were determined. Alkaline conditions increased insolubility caused yellowing and increased pasting properties significantly. Acidic conditions increased solubility and decreased WPI pasting properties. Subtle structural changes occurred under acidic conditions, but were more pronounced under alkaline conditions. Overall, alkaline conditions increased denaturation in the extruded WPI resulting in stringy texturized WPI products, which could be used in meat applications.

  8. Clostridium perfringens Sporulation and Sporulation-Associated Toxin Production

    Science.gov (United States)

    Li, Jihong; Paredes-Sabja, Daniel; Sarker, Mahfuzur R.; McClane, Bruce A.

    2015-01-01

    The ability of Clostridium perfringens to form spores plays a key role during the transmission of this Gram-positive bacterium to cause disease. Of particular note, the spores produced by food poisoning strains are often exceptionally resistant to food environment stresses such as heat, cold and preservatives, which likely facilitates their survival in temperature-abused foods. The exceptional resistance properties of spores made by most type A food poisoning strains and some type C foodborne disease strains involves their production of a variant small acid soluble protein-4 that binds more tightly to spore DNA compared to the small acid soluble protein-4 made by most other C. perfringens strains. Sporulation and germination by C. perfringens and Bacillus spp. share both similarities and differences. Finally, sporulation is essential for production of C. perfringens enterotoxin, which is responsible for the symptoms of C. perfringens type A food poisoning, the second most common bacterial foodborne disease in the USA. During this foodborne disease, C. perfringens is ingested with food and then, using sporulation-specific alternate sigma factors, this bacterium sporulates and produces the enterotoxin in the intestines. PMID:27337447

  9. N-3 Polyunsaturated Fatty Acids Decrease the Protein Expression of Soluble Epoxide Hydrolase via Oxidative Stress-Induced P38 Kinase in Rat Endothelial Cells.

    Science.gov (United States)

    Okada, Takashi; Morino, Katsutaro; Nakagawa, Fumiyuki; Tawa, Masashi; Kondo, Keiko; Sekine, Osamu; Imamura, Takeshi; Okamura, Tomio; Ugi, Satoshi; Maegawa, Hiroshi

    2017-06-24

    N -3 polyunsaturated fatty acids (PUFAs) improve endothelial function. The arachidonic acid-derived metabolites (epoxyeicosatrienoic acids (EETs)) are part of the endothelial hyperpolarization factor and are vasodilators independent of nitric oxide. However, little is known regarding the regulation of EET concentration by docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in blood vessels. Sprague-Dawley rats were fed either a control or fish oil diet for 3 weeks. Compared with the control, the fish oil diet improved acetylcholine-induced vasodilation and reduced the protein expression of soluble epoxide hydrolase (sEH), a key EET metabolic enzyme, in aortic strips. Both DHA and EPA suppressed sEH protein expression in rat aorta endothelial cells (RAECs). Furthermore, the concentration of 4-hydroxy hexenal (4-HHE), a lipid peroxidation product of n -3 PUFAs, increased in n -3 PUFA-treated RAECs. In addition, 4-HHE treatment suppressed sEH expression in RAECs, suggesting that 4-HHE (derived from n -3 PUFAs) is involved in this phenomenon. The suppression of sEH was attenuated by the p38 kinase inhibitor (SB203580) and by treatment with the antioxidant N-acetyl-L-cysteine. In conclusion, sEH expression decreased after n -3 PUFAs treatment, potentially through oxidative stress and p38 kinase. Mild oxidative stress induced by n -3 PUFAs may contribute to their cardio-protective effect.

  10. Spore inactivation and DPA release in Alicyclobacillus acidoterrestris under different stress conditions.

    Science.gov (United States)

    Bevilacqua, Antonio; Ciuffreda, Emanuela; Sinigaglia, Milena; Corbo, Maria Rosaria

    2015-04-01

    This paper reports on the inactivation of spores of 5 strains of Alicyclobacillus acidoterrestris under different stress conditions (acidic and alkaline pH, high temperature, addition of lysozyme, hydrogen peroxide and p-coumaric acid). The research was divided into two different steps; first, each stress was studied alone, thus pointing out a partial uncoupling between spore inactivation and DPA release, as H2O2 reduced spore level below the detection but it did not cause the release of DPA. A partial correlation was found only for acidic and alkaline pH. 2nd step was focused on the combination of pH, temperature and H2O2 through a factorial design; experiments were performed on both fresh and 4 month-old spores and pinpointed a different trend for DPA release as a function of spore age. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. A Cumulative Spore Killing Approach: Synergistic Sporicidal Activity of Dilute Peracetic Acid and Ethanol at Low pH Against Clostridium difficile and Bacillus subtilis Spores.

    Science.gov (United States)

    Nerandzic, Michelle M; Sankar C, Thriveen; Setlow, Peter; Donskey, Curtis J

    2016-01-01

    Background.  Alcohol-based hand sanitizers are the primary method of hand hygiene in healthcare settings, but they lack activity against bacterial spores produced by pathogens such as Clostridium difficile and Bacillus anthracis. We previously demonstrated that acidification of ethanol induced rapid sporicidal activity, resulting in ethanol formulations with pH 1.5-2 that were as effective as soap and water washing in reducing levels of C difficile spores on hands. We hypothesized that the addition of dilute peracetic acid (PAA) to acidified ethanol would enhance sporicidal activity while allowing elevation of the pH to a level likely to be well tolerated on skin (ie, >3). Methods.  We tested the efficacy of acidified ethanol solutions alone or in combination with PAA against C difficile and Bacillus subtilis spores in vitro and against nontoxigenic C difficile spores on hands of volunteers. Results.  Acidification of ethanol induced rapid sporicidal activity against C difficile and to a lesser extent B subtilis. The addition of dilute PAA to acidified ethanol resulted in synergistic enhancement of sporicidal activity in a dose-dependent fashion in vitro. On hands, the addition of 1200-2000 ppm PAA enhanced the effectiveness of acidified ethanol formulations, resulting in formulations with pH >3 that were as effective as soap and water washing. Conclusions.  Acidification and the addition of dilute PAA induced rapid sporicidal activity in ethanol. Our findings suggest that it may be feasible to develop effective sporicidal ethanol formulations that are safe and tolerable on skin.

  12. Drug Solubility in Fatty Acids as a Formulation Design Approach for Lipid-Based Formulations: A Technical Note.

    Science.gov (United States)

    Lee, Yung-Chi; Dalton, Chad; Regler, Brian; Harris, David

    2018-06-06

    Lipid-based drug delivery systems have been intensively investigated as a means of delivering poorly water-soluble drugs. Upon ingestion, the lipases in the gastrointestinal tract digest lipid ingredients, mainly triglycerides, within the formulation into monoglycerides and fatty acids. While numerous studies have addressed the solubility of drugs in triglycerides, comparatively few publications have addressed the solubility of drugs in fatty acids, which are the end product of digestion and responsible for the solubility of drug within mixed micelles. The objective of this investigation was to explore the solubility of a poorly water-soluble drug in fatty acids and raise the awareness of the importance of drug solubility in fatty acids. The model API (active pharmaceutical ingredient), a weak acid, is considered a BCS II compound with an aqueous solubility of 0.02 μg/mL and predicted partition coefficient >7. The solubility of API ranged from 120 mg/mL to over 1 g/mL in fatty acids with chain lengths across the range C18 to C6. Hydrogen bonding was found to be the main driver of the solubilization of API in fatty acids. The solubility of API was significantly reduced by water uptake in caprylic acid but not in oleic acid. This report demonstrates that solubility data generated in fatty acids can provide an indication of the solubility of the drug after lipid digestion. This report also highlights the importance of measuring the solubility of drugs in fatty acids in the course of lipid formulation development.

  13. Efficient protein production method for NMR using soluble protein tags with cold shock expression vector

    International Nuclear Information System (INIS)

    Hayashi, Kokoro; Kojima, Chojiro

    2010-01-01

    The E. coli protein expression system is one of the most useful methods employed for NMR sample preparation. However, the production of some recombinant proteins in E. coli is often hampered by difficulties such as low expression level and low solubility. To address these problems, a modified cold-shock expression system containing a glutathione S-transferase (GST) tag, the pCold-GST system, was investigated. The pCold-GST system successfully expressed 9 out of 10 proteins that otherwise could not be expressed using a conventional E. coli expression system. Here, we applied the pCold-GST system to 84 proteins and 78 proteins were successfully expressed in the soluble fraction. Three other cold-shock expression systems containing a maltose binding protein tag (pCold-MBP), protein G B1 domain tag (pCold-GB1) or thioredoxin tag (pCold-Trx) were also developed to improve the yield. Additionally, we show that a C-terminal proline tag, which is invisible in 1 H- 15 N HSQC spectra, inhibits protein degradation and increases the final yield of unstable proteins. The purified proteins were amenable to NMR analyses. These data suggest that pCold expression systems combined with soluble protein tags can be utilized to improve the expression and purification of various proteins for NMR analysis.

  14. An odd–even effect on solubility of dicarboxylic acids in organic solvents

    International Nuclear Information System (INIS)

    Zhang, Hui; Yin, Qiuxiang; Liu, Zengkun; Gong, Junbo; Bao, Ying; Zhang, Meijing; Hao, Hongxun; Hou, Baohong; Xie, Chuang

    2014-01-01

    Highlights: • The solubilities of the homologous series of C2–C10 dicarboxylic acids were determined in four selected solvents. • The experimental data were well correlated with the modified Apelblat equation. • The odd–even effect of solubility was found and explained. • The enthalpy, entropy and the molar Gibbs free energy of solution were predicted. - Abstract: The solubility of the homologous series of dicarboxylic acids, HOOC-(CH 2 ) n−2 -COOH (n = 2 to 10), in ethanol, acetic acid, acetone and ethyl acetate was measured at temperatures ranging from (278.15 to 323.15) K by a static analytic method at atmospheric pressure. Dicarboxylic acids with even number of carbon atoms exhibit lower values of solubility than adjacent homologues with odd carbon numbers. This odd–even effect of solubility is attributed to the twist of molecules and interlayer packing in solid state as explained in our previous work. The alternation varies in different solvents, which is believed to be associated with the properties of solvents. Finally, the dissolution enthalpy, dissolution entropy and the molar Gibbs free energy were calculated using the fitting parameters of the modified Apelblat equation. The molar Gibbs free energy also showed apparent odd–even alternation in keeping with the alternation of solubility

  15. Limitations of polyethylene glycol-induced precipitation as predictive tool for protein solubility during formulation development.

    Science.gov (United States)

    Hofmann, Melanie; Winzer, Matthias; Weber, Christian; Gieseler, Henning

    2018-05-01

    Polyethylene glycol (PEG)-induced protein precipitation is often used to extrapolate apparent protein solubility at specific formulation compositions. The procedure was used for several fields of application such as protein crystal growth but also protein formulation development. Nevertheless, most studies focused on applicability in protein crystal growth. In contrast, this study focuses on applicability of PEG-induced precipitation during high-concentration protein formulation development. In this study, solubility of three different model proteins was investigated over a broad range of pH. Solubility values predicted by PEG-induced precipitation were compared to real solubility behaviour determined by either turbidity or content measurements. Predicted solubility by PEG-induced precipitation was confirmed for an Fc fusion protein and a monoclonal antibody. In contrast, PEG-induced precipitation failed to predict solubility of a single-domain antibody construct. Applicability of PEG-induced precipitation as indicator of protein solubility during formulation development was found to be not valid for one of three model molecules. Under certain conditions, PEG-induced protein precipitation is not valid for prediction of real protein solubility behaviour. The procedure should be used carefully as tool for formulation development, and the results obtained should be validated by additional investigations. © 2017 Royal Pharmaceutical Society.

  16. The Influence of Tissue Lyophilization and Gamma Irradiation on the Solubility of Proteins

    International Nuclear Information System (INIS)

    Komender, J.; Jendyk, J.; Leibschang, J.

    1967-01-01

    Most recent methods of tissue preservation are based on lyophilization and sterilization with gamma rays. Unfortunately the tissues preserved by this method lose their viability, this being connected with protein denaturation. The denaturing influence either of lyophilization or sterilization with gamma rays on different materials has been described. However, no observations on denaturation of proteins in prepared grafts are known. The work aimed at establishing the influence of individual stages of the procedure used in a tissue bank on the solubility of proteins. An experiment was performed using rat liver as a model tissue. Solubility of protein was determined in five groups of material, as follows: (1) fresh tissue, used as a control, (2) frozen tissue, (3) frozen and lyophilized tissue, (4) frozen, lyophilized and irradiated tissue, and (5) fresh irradiated tissue. Folin's method was used for determination of protein in water extracts of tissues. It was found that: (1) the whole procedure considerably diminished the protein solubility, (2) freezing diminishes the protein solubility by 35% on average, (3) lyophilization causes no further protein denaturation, (4) protein solubility is reduced most (by about 65%) by sterilization with gamma rays. (author)

  17. Diverse supramolecular structures formed by self‐assembling proteins of the B acillus subtilis spore coat

    Science.gov (United States)

    Jiang, Shuo; Wan, Qiang; Krajcikova, Daniela; Tang, Jilin; Tzokov, Svetomir B.; Barak, Imrich

    2015-01-01

    Summary Bacterial spores (endospores), such as those of the pathogens C lostridium difficile and B acillus anthracis, are uniquely stable cell forms, highly resistant to harsh environmental insults. B acillus subtilis is the best studied spore‐former and we have used it to address the question of how the spore coat is assembled from multiple components to form a robust, protective superstructure. B . subtilis coat proteins (CotY, CotE, CotV and CotW) expressed in E scherichia coli can arrange intracellularly into highly stable macro‐structures through processes of self‐assembly. Using electron microscopy, we demonstrate the capacity of these proteins to generate ordered one‐dimensional fibres, two‐dimensional sheets and three‐dimensional stacks. In one case (CotY), the high degree of order favours strong, cooperative intracellular disulfide cross‐linking. Assemblies of this kind could form exquisitely adapted building blocks for higher‐order assembly across all spore‐formers. These physically robust arrayed units could also have novel applications in nano‐biotechnology processes. PMID:25872412

  18. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol–Water Mixtures

    Science.gov (United States)

    2018-01-01

    The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization. We reviewed the available data on the solubility of α-amino acids in water, water–ethanol mixtures, and ethanol at 298.15 K and 0.1 MPa. The solubility of l-alanine, l-proline, l-arginine, l-cysteine, and l-lysine in water and ethanol mixtures and the solubility of l-alanine, l-proline, l-arginine, l-cysteine, l-lysine, l-asparagine, l-glutamine, l-histidine, and l-leucine in pure ethanol systems were measured and are published here for the first time. The impact on the solubility of amino acids that can convert in solution, l-glutamic acid and l-cysteine, was studied. At lower concentrations, only the ninhydrin method and the ultraperfomance liquid chromatography (UPLC) method yield reliable results. In the case of α-amino acids that convert in solution, only the UPLC method was able to discern between the different α-amino acids and yields reliable results. Our results demonstrate that α-amino acids with similar physical structures have similar changes in solubility in mixed water/ethanol mixtures. The solubility of l-tryptophan increased at moderate ethanol concentrations. PMID:29545650

  19. A facile physical approach to make chitosan soluble in acid-free water.

    Science.gov (United States)

    Fu, Yinghao; Xiao, Congming

    2017-10-01

    We changed the situation that chitosan was only dissolved in diluted acid through mild physical treatment. In viewing of the usual methods to modify chitosan are chemical ones, we established the approach by using a water-soluble chitosan derivative as the model polymer. Its water-solubility was modulated via changing the concentration of solution and varying the precipitants. Such a physical method was adopted to treat chitiosan. One gram chitosan was dissolved in a mixture of 100mL 10% acetic acid and 50mL methanol, and then precipitated from a precipitant consisted of 10mL ethanol and 90mL acetate ester. The treated chitosan became soluble in acid-free water completely, and its solubility was 8.02mg/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. High-level expression of soluble recombinant proteins in Escherichia coli using an HE-maltotriose-binding protein fusion tag.

    Science.gov (United States)

    Han, Yingqian; Guo, Wanying; Su, Bingqian; Guo, Yujie; Wang, Jiang; Chu, Beibei; Yang, Guoyu

    2018-02-01

    Recombinant proteins are commonly expressed in prokaryotic expression systems for large-scale production. The use of genetically engineered affinity and solubility enhancing fusion proteins has increased greatly in recent years, and there now exists a considerable repertoire of these that can be used to enhance the expression, stability, solubility, folding, and purification of their fusion partner. Here, a modified histidine tag (HE) used as an affinity tag was employed together with a truncated maltotriose-binding protein (MBP; consisting of residues 59-433) from Pyrococcus furiosus as a solubility enhancing tag accompanying a tobacco etch virus protease-recognition site for protein expression and purification in Escherichia coli. Various proteins tagged at the N-terminus with HE-MBP(Pyr) were expressed in E. coli BL21(DE3) cells to determine expression and solubility relative to those tagged with His6-MBP or His6-MBP(Pyr). Furthermore, four HE-MBP(Pyr)-fused proteins were purified by immobilized metal affinity chromatography to assess the affinity of HE with immobilized Ni 2+ . Our results showed that HE-MBP(Pyr) represents an attractive fusion protein allowing high levels of soluble expression and purification of recombinant protein in E. coli. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Efficient protein production method for NMR using soluble protein tags with cold shock expression vector

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Kokoro [Fujifilm Corporation, Analysis Technology Center (Japan); Kojima, Chojiro, E-mail: kojima@protein.osaka-u.ac.j [Nara Institute of Science and Technology (NAIST), Graduate School of Biological Sciences (Japan)

    2010-11-15

    The E. coli protein expression system is one of the most useful methods employed for NMR sample preparation. However, the production of some recombinant proteins in E. coli is often hampered by difficulties such as low expression level and low solubility. To address these problems, a modified cold-shock expression system containing a glutathione S-transferase (GST) tag, the pCold-GST system, was investigated. The pCold-GST system successfully expressed 9 out of 10 proteins that otherwise could not be expressed using a conventional E. coli expression system. Here, we applied the pCold-GST system to 84 proteins and 78 proteins were successfully expressed in the soluble fraction. Three other cold-shock expression systems containing a maltose binding protein tag (pCold-MBP), protein G B1 domain tag (pCold-GB1) or thioredoxin tag (pCold-Trx) were also developed to improve the yield. Additionally, we show that a C-terminal proline tag, which is invisible in {sup 1}H-{sup 15}N HSQC spectra, inhibits protein degradation and increases the final yield of unstable proteins. The purified proteins were amenable to NMR analyses. These data suggest that pCold expression systems combined with soluble protein tags can be utilized to improve the expression and purification of various proteins for NMR analysis.

  2. Levels of acid-soluble polyphosphate in growing cultures of Saccharomyces cerevisiae.

    OpenAIRE

    Solimene, R; Guerrini, A M; Donini, P

    1980-01-01

    Short-chain acid-soluble polyphosphates were extracted from growing cultures of Saccharomyces cerevisiae, and the changes in the levels of these compounds were determined. The production of acid-soluble polyphosphates correlated with the mitochondrial activities since it occurred in two bursts in respiration-competent yeast cells and in only one burst in respiration-deficient yeast cells. The possible role of these compounds is discussed.

  3. Efficiency of peracetic acid in inactivating bacteria, viruses, and spores in water determined with ATP bioluminescence, quantitative PCR, and culture-based methods.

    Science.gov (United States)

    Park, Eunyoung; Lee, Cheonghoon; Bisesi, Michael; Lee, Jiyoung

    2014-03-01

    The disinfection efficiency of peracetic acid (PAA) was investigated on three microbial types using three different methods (filtration-based ATP (adenosine-triphosphate) bioluminescence, quantitative polymerase chain reaction (qPCR), culture-based method). Fecal indicator bacteria (Enterococcus faecium), virus indicator (male-specific (F(+)) coliphages (coliphages)), and protozoa disinfection surrogate (Bacillus subtilis spores (spores)) were tested. The mode of action for spore disinfection was visualized using scanning electron microscopy. The results indicated that PAA concentrations of 5 ppm (contact time: 5 min), 50 ppm (10 min), and 3,000 ppm (5 min) were needed to achieve 3-log reduction of E. faecium, coliphages, and spores, respectively. Scanning electron microscopy observation showed that PAA targets the external layers of spores. The lower reduction rates of tested microbes measured with qPCR suggest that qPCR may overestimate the surviving microbes. Collectively, PAA showed broad disinfection efficiency (susceptibility: E. faecium > coliphages > spores). For E. faecium and spores, ATP bioluminescence was substantially faster (∼5 min) than culture-based method (>24 h) and qPCR (2-3 h). This study suggests PAA as an effective alternative to inactivate broad types of microbial contaminants in water. Together with the use of rapid detection methods, this approach can be useful for urgent situations when timely response is needed for ensuring water quality.

  4. Fermentation of calcium-fortified soymilk with Lactobacillus: effects on calcium solubility, isoflavone conversion, and production of organic acids.

    Science.gov (United States)

    Tang, A L; Shah, N P; Wilcox, G; Walker, K Z; Stojanovska, L

    2007-11-01

    The objective of this study was to enhance calcium solubility and bioavailability from calcium-fortified soymilk by fermentation with 7 strains of Lactobacillus, namely, L. acidophilus ATCC 4962, ATCC33200, ATCC 4356, ATCC 4461, L. casei ASCC 290, L. plantarum ASCC 276, and L. fermentum VRI-003. The parameters that were used are viability, pH, calcium solubility, organic acid, and biologically active isoflavone aglycone content. Calcium-fortified soymilk made from soy protein isolate was inoculated with these probiotic strains, incubated for 24 h at 37 degrees C, then stored for 14 d at 4 degrees C. Soluble calcium was measured using atomic absorption spectrophotometry (AA). Organic acids and bioactive isoflavone aglycones, including diadzein, genistein, and glycetein, were measured using HPLC. Viability of the strains in the fermented calcium-fortified soymilk was > 8.5 log(10) CFU/g after 24 h fermentation and this was maintained for 14-d storage at 4 degrees C. After 24 h, there was a significant increase (P casei ASCC 290 demonstrated the highest increase with 89.3% and 87.0% soluble calcium after 24 h, respectively. The increase in calcium solubility observed was related to lowered pH associated with production of lactic and acetic acids. Fermentation significantly increased (P < 0.05) the level of conversion of isoflavones into biologically active aglycones, including diadzein, genistein, and glycetein. Our results show that fermenting calcium-fortified soymilk with the selected probiotics can potentially enhance the calcium bioavailability of calcium-fortified soymilk due to increased calcium solubility and bioactive isoflavone aglycone enrichment.

  5. Lipoquinones of some spore-forming rods, lactic-acid bacteria and actinomycetes.

    Science.gov (United States)

    Hess, A; Holländer, R; Mannheim, W

    1979-11-01

    The respiratory quinones of 73 strains of Gram-positive bacteria including spore-forming rods, lactic-acid bacteria and actinomyctes were examined. Menaquinones with seven isoprenoid units (MK-7) were the main quinone type found in representatives of the genus Bacillus and in Sporolactobacillus inulinus. However, a strain of B. thuringiensis produced MK-8 in addition to MK-7, and strains of B. lentus and B. pantothenticus appeared to produce MK-9 and MK-8, respectively, with no MK-7. In the clostridia and lactic-acid bacteria, no quinones were found, except in Pediococcus cerevisiae NCTC 8066 and Lactobacillus casei subsp. rhamnosus ATCC 7469, which contained menaquinones, and Streptococcus faecalis NCTC 775 and HIM 478-1, which contained demethylmenaquinones, in relatively low concentrations. Menaquinones were also found in the actinomycetes (except Actinomyces odontolyticus and Bifidobacterium bifidum which did not produce any quinones) and in Protaminobacter alboflavus ATCC 8458, the so-called Actinobacillus actinoides ATCC 15900 and Noguchia granulosis NCTC 10559.

  6. Soluble proteins from fowl feather keratin. II. Isolation of some proteins from barbs.

    Science.gov (United States)

    Murayama, K; Akahane, K; Murozono, S

    1977-01-01

    Four fractions, GF-1, 2, 3, and 4, which had been separated from S-carboxymethylated (SCM-) proteins of fowl feathers by gel filtration, were each chromatographed on a DEAE-cellulose column in 0.05 M Tris-HCl buffer (pH 8.5) containing 8 M urea. The major fraction, GF-3, was further separated into seven peaks; the first four were shown to be single components by polyacrylamide disc gel electrophoresis. Chromatograms of GF-1 and 2 showed broad peaks which appeared at nearly the same volume as in GF-3. The components from GF-3 had very similar amino acid compositions except that the SCM-cysteine content showed a tendency to increase in the order of elution from the column. SCM-extract prepared from barbs of the wing feathers of a fowl was more heterogeneous than that taken from the body feathers. A combination of gel filtration on Sephadex G-75 and chromatography on DEAE-cellulose was found to be more effective for the isolation of soluble SCM-proteins.

  7. delta 6 Hexadecenoic acid is synthesized by the activity of a soluble delta 6 palmitoyl-acyl carrier protein desaturase in Thunbergia alata endosperm.

    Science.gov (United States)

    Cahoon, E B; Cranmer, A M; Shanklin, J; Ohlrogge, J B

    1994-11-04

    delta 6 Hexadecenoic acid (16:1 delta 6) composes more than 80% of the seed oil of Thunbergia alata. Studies were conducted to determine the biosynthetic origin of the double bond of this unusual fatty acid. Assays of fractions of developing T. alata seed endosperm with [1-14C]palmitoyl (16:0)-acyl carrier protein (ACP) revealed the presence of a soluble delta 6 desaturase activity. This activity was greatest when 16:0-ACP was provided as a substrate, whereas no desaturation of the coenzyme A ester of this fatty acid was detected. In addition, delta 6 16:0-ACP desaturase activity in T. alata endosperm extracts was dependent on the presence of ferredoxin and molecular oxygen and was stimulated by catalase. To further characterize this enzyme, a cDNA encoding a diverged acyl-ACP desaturase was isolated from a T. alata endosperm cDNA library using polymerase chain reaction with degenerate oligonucleotides corresponding to conserved amino acid sequences in delta 9 stearoyl (18:0)- and delta 4 16:0-ACP desaturases. The primary structure of the mature peptide encoded by this cDNA shares 66% identity with the mature castor delta 9 18:0-ACP desaturase and 57% identity with the mature coriander delta 4 16:0-ACP desaturase. Extracts of Escherichia coli that express the T. alata cDNA catalyzed the delta 6 desaturation of 16:0-ACP. These results demonstrate that 16:1 delta 6 in T. alata endosperm is formed by the activity of a soluble delta 6 16:0-ACP desaturase that is structurally related to the delta 9 18:0- and delta 4 16:0-ACP desaturases. Implications of this work to an understanding of active site structures of acyl-ACP desaturases are discussed.

  8. Analysis of the ligand binding properties of recombinant bovine liver-type fatty acid binding protein

    DEFF Research Database (Denmark)

    Rolf, B; Oudenampsen-Krüger, E; Börchers, T

    1995-01-01

    The coding part of the cDNA for bovine liver-type fatty acid binding protein (L-FABP) has been amplified by RT-PCR, cloned and used for the construction of an Escherichia coli (E. coli) expression system. The recombinant protein made up to 25% of the soluble E. coli proteins and could be isolated...

  9. Salt and cocrystals of sildenafil with dicarboxylic acids: solubility and pharmacokinetic advantage of the glutarate salt.

    Science.gov (United States)

    Sanphui, Palash; Tothadi, Srinu; Ganguly, Somnath; Desiraju, Gautam R

    2013-12-02

    Sildenafil is a drug used to treat erectile dysfunction and pulmonary arterial hypertension. Because of poor aqueous solubility of the drug, the citrate salt, with improved solubility and pharmacokinetics, has been marketed. However, the citrate salt requires an hour to reach its peak plasma concentration. Thus, to improve solubility and bioavailability characteristics, cocrystals and salts of the drug have been prepared by treating aliphatic dicarboxylic acids with sildenafil; the N-methylated piperazine of the drug molecule interacts with the carboxyl group of the acid to form a heterosynthon. Salts are formed with oxalic and fumaric acid; salt monoanions are formed with succinic and glutaric acid. Sildenafil forms cocrystals with longer chain dicarboxylic acids such as adipic, pimelic, suberic, and sebacic acids. Auxiliary stabilization via C-H···O interactions is also present in these cocrystals and salts. Solubility experiments of sildenafil cocrystal/salts were carried out in 0.1N HCl aqueous medium and compared with the solubility of the citrate salt. The glutarate salt and pimelic acid cocrystal dissolve faster than the citrate salt in a two hour dissolution experiment. The glutarate salt exhibits improved solubility (3.2-fold) compared to the citrate salt in water. Solubilities of the binary salts follow an inverse correlation with their melting points, while the solubilities of the cocrystals follow solubilities of the coformer. Pharmacokinetic studies on rats showed that the glutarate salt exhibits doubled plasma AUC values in a single dose within an hour compared to the citrate salt. The high solubility of glutaric acid, in part originating from the strained conformation of the molecule and its high permeability, may be the reason for higher plasma levels of the drug.

  10. Architecture and assembly of the Bacillus subtilis spore coat.

    Science.gov (United States)

    Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J

    2014-01-01

    Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of "nanodot" particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization

  11. Architecture and Assembly of the Bacillus subtilis Spore Coat

    Science.gov (United States)

    Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J.

    2014-01-01

    Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of “nanodot” particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization

  12. The performance of a soluble lead-acid flow battery and its comparison to a static lead-acid battery

    International Nuclear Information System (INIS)

    Zhang, C.P.; Sharkh, S.M.; Li, X.; Walsh, F.C.; Zhang, C.N.; Jiang, J.C.

    2011-01-01

    Highlights: → We compared the electrochemical characteristics of two types of the batteries. → SLAFB shows as good performance as SLAB under the same current density. → The cycle life of two batteries is strongly influenced by the depth of discharge. → The cycle life of SLAFB can be extended by treatment with hydrogen peroxide. - Abstract: The electrochemistry of static lead-acid and soluble lead-acid flow batteries is summarised and the differences between the two batteries are highlighted. A general comparison of the performance of an unoptimised soluble lead-acid flow laboratory cell and a commercial lead-acid battery during charge and discharge is reported. The influence of the depth of discharge on cycle life for both batteries is also considered. The flow battery was found to have a better charge efficiency than the static one, but the cells were found to have comparable energy efficiencies. The self-discharge characteristics of the soluble lead-acid battery were also measured and compared to reported values for a commercial static battery. Some self-discharge of the soluble lead-acid flow battery is observed during prolonged periods on open-circuit but the battery could recover its normal performance after a single charge-discharge cycle.

  13. Solubility of gallic acid in liquid mixtures of (ethanol + water) from (293.15 to 318.15) K

    International Nuclear Information System (INIS)

    Noubigh, Adel; Jeribi, Chokri; Mgaidi, Arbi; Abderrabba, Manef

    2012-01-01

    Graphical abstract: Solubility of gallic acid vs the mole fraction of ethanol (0.0 to 1) on a solute-free basis in ethanol + water at different temperatures/K. □, 293.15; Δ, 298.15; ◊, 303.15; line calculated by equation. Highlights: ► Solubilities of gallic acid in binary mixtures were determined over the temperatures range (293.15 to 318.15) K. ► The gallic acid solubility in mixed solvents presents a maximum-solubility effect. ► Two empirical equations were proposed to correlate the solubility Data. ► The thermodynamic properties were determined. - Abstract: The solubility of gallic acid in (water + ethanol) binary solvents was determined from (293.15 to 318.15) K at atmospheric pressure using a thermostatted reactor and UV/vis spectrophotometer analysis. The effects of binary solvents composition and temperature on the solubility were discussed. It was found that gallic acid solubility in (water + ethanol) mixed solvents presents a maximum-solubility effect. Two empirical equations were proposed to correlate the solubility data. The calculated solubilities show good agreement with the experimental data within the studied temperature range. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of the gallic acid such as Gibbs energy (Δ sol G°), molar enthalpy of dissolution (Δ sol H°), and molar entropy of dissolution (Δ sol S°) were calculated.

  14. Plasma Amino Acid Responses After Consumption of Beverages with Varying Protein Type

    Science.gov (United States)

    2009-07-01

    saturated fat Protein Total earbohydT;ltes dietary fiber soluble fiber total sugar lactose sucrose other carbohydrates (maltodextrin. cocoa powder...provided by the manufacturer, 6 Plasma Amino Acids 7 coagulate for 30 min before being centrifuged for 10 min at 3,600 rpm. Resulting plasma and serum...Therefore, consumers should be aware that these products might not contain the specific protein sources being advertised. Acknowledgment The authors

  15. Formation and characterization of non-growth states in Clostridium thermocellum: spores and L-forms

    Directory of Open Access Journals (Sweden)

    Mearls Elizabeth B

    2012-08-01

    Full Text Available Abstract Background Clostridium thermocellum is an anaerobic thermophilic bacterium that exhibits high levels of cellulose solublization and produces ethanol as an end product of its metabolism. Using cellulosic biomass as a feedstock for fuel production is an attractive prospect, however, growth arrest can negatively impact ethanol production by fermentative microorganisms such as C. thermocellum. Understanding conditions that lead to non-growth states in C. thermocellum can positively influence process design and culturing conditions in order to optimize ethanol production in an industrial setting. Results We report here that Clostridium thermocellum ATCC 27405 enters non-growth states in response to specific growth conditions. Non-growth states include the formation of spores and a L-form-like state in which the cells cease to grow or produce the normal end products of metabolism. Unlike other sporulating organisms, we did not observe sporulation of C. thermocellum in low carbon or nitrogen environments. However, sporulation did occur in response to transfers between soluble and insoluble substrates, resulting in approximately 7% mature spores. Exposure to oxygen caused a similar sporulation response. Starvation conditions during continuous culture did not result in spore formation, but caused the majority of cells to transition to a L-form state. Both spores and L-forms were determined to be viable. Spores exhibited enhanced survival in response to high temperature and prolonged storage compared to L-forms and vegetative cells. However, L-forms exhibited faster recovery compared to both spores and stationary phase cells when cultured in rich media. Conclusions Both spores and L-forms cease to produce ethanol, but provide other advantages for C. thermocellum including enhanced survival for spores and faster recovery for L-forms. Understanding the conditions that give rise to these two different non-growth states, and the implications that

  16. Action of mercurials on activity of partially purified soluble protein kinase C from mice brain

    International Nuclear Information System (INIS)

    Inoue, Y.; Saijoh, K.; Sumino, K.

    1988-01-01

    The enzymatic activity of soluble protein kinase C from mice brain was inhibited by mercuric chloride (II) (HgCl 2 ) and organic mercurials, i.e. methyl mercury, phenyl mercury and p-chloromercuribenzoic acid (PCMB). The IC50 was 0.08 μM for HgCl 2 and about 1 μM for organic mercurials. Sulfhydryl blocking reagents such as 5.5'-dithiobis-2-nitrobenzoic acid (DTNB) and N-ethylmaleimide (NEM) were less potent but nevertheless inhibited the enzymic activity of protein kinase C. The Hill coefficients of HgCl 2 , DTNB and NEM were close to unity whereas the values for organic mercurials were 1.3 to 1.5. The inhibition was of a non-competitive type with respect to Hl histone. 3 H-PDBu binding activity was also inhibited by all of the reagents in a non-competitive manner. Mercurials apparently bind to sulfhydryl groups of protein kinase C to inhibit the enzymatic activity. (author)

  17. Effect of incubation temperature and pH on the recovery of Bacillus weihenstephanensis spores after exposure to a peracetic acid-based disinfectant or to pulsed light.

    Science.gov (United States)

    Trunet, C; Mtimet, N; Mathot, A-G; Postollec, F; Leguérinel, I; Couvert, O; Carlin, F; Coroller, L

    2018-04-12

    The recovery at a range of incubation temperatures and pH of spores of Bacillus weihenstephanensis KBAB4 exposed to a peracetic acid-based disinfectant (PABD) or to pulsed light was estimated. Spores of B. weihenstephanensis were produced at 30 °C and pH 7.00, at 30 °C and pH 5.50, or at 12 °C and pH 7.00. The spores were treated with a commercial peracetic acid-based disinfectant at 80 mg·mL -1 for 0 to 200 min at 18 °C or by pulsed light at fluences ranging between 0.4 and 2.3 J·cm -2 for pulsed light treatment. After each treatment, the spores were incubated on nutrient agar at 12 °C, 30 °C or 37 °C, or at pH 5.10, 6.00 or 7.40. Incubation temperature during recovery had a significant impact only near the recovery limits, beyond which surviving spores previously exposed to a PABD or to pulsed light were not able to form colonies. In contrast, a decrease in pH of the recovery nutrient agar had a progressive impact on the ability of spores to form colonies. The time to first log reduction after PABD treatment was 29.5 ± 0.7 min with recovery at pH 7.40, and was tremendously shortened 5.1 ± 0.2 min with recovery at pH 5.10. Concerning the fluence necessary for the first log reduction, it was 1.5 times higher when the spores were recovered at pH 6.00 compared to a recovery at pH 5.10. The impact of recovery temperature and pH can be described with a mathematical model using cardinal temperature and pH as parameters. These effects of temperature and pH on recovery of Bacillus weihenstephanensis spores exposed to a disinfectant combining peracetic acid and hydrogen peroxide, or pulsed light are similar, although these treatments are of different natures. Sporulation temperature or pH did not impact resistance to the peracetic acid-based disinfectant or pulsed light. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Production of a highly active, soluble form of the cytochrome P450 reductase (CPR A) from Candida tropicalis

    Science.gov (United States)

    Donnelly, Mark

    2006-08-01

    The present invention provides soluble cytochrome p450 reductase (CPR) proteins from Candida sp. having an altered N-terminal region which results in reduced hydrophobicity of the N-terminal region. Also provided are host cells comprising the subject soluble CPR proteins. In addition, the present invention provides nucleotide and corresponding amino acid sequences for soluble CPR proteins and vectors comprising the nucleotide sequences. Methods for producing a soluble CPR, for increasing production of a dicarboxylic acid, and for detecting a cytochrome P450 are also provided.

  19. Novel mitochondria-targeted heat-soluble proteins identified in the anhydrobiotic Tardigrade improve osmotic tolerance of human cells.

    Directory of Open Access Journals (Sweden)

    Sae Tanaka

    Full Text Available Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called "anhydrobiosis". Late Embryogenesis Abundant (LEA proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble and SAHS (Secretory Abundant Heat Soluble proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble, as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments.

  20. Profiling and relationship of water-soluble sugar and protein compositions in soybean seeds.

    Science.gov (United States)

    Yu, Xiaomin; Yuan, Fengjie; Fu, Xujun; Zhu, Danhua

    2016-04-01

    Sugar and protein are important quality traits in soybean seeds for making soy-based food products. However, the investigations on both compositions and their relationship have rarely been reported. In this study, a total of 35 soybean germplasms collected from Zhejiang province of China, were evaluated for both water-soluble sugar and protein. The total water-soluble sugar (TWSS) content of the germplasms studied ranged from 84.70 to 140.91 mg/g and the water-soluble protein (WSP) content varied from 26.5% to 36.0%. The WSP content showed positive correlations with the TWSS and sucrose contents but negative correlations with the fructose and glucose contents. The clustering showed the 35 germplasms could be divided into four groups with specific contents of sugar and protein. The combination of water-soluble sugar and protein profiles provides useful information for future breeding and genetic research. This investigation will facilitate future work for seed quality improvement. Copyright © 2015. Published by Elsevier Ltd.

  1. The effect of ethylenediaminetetraacetic acid on heat resistance and recovery of Clostridium sporogenes PA 3679 spores treated in HTST conditions.

    Science.gov (United States)

    Silla Santos, M H; Torres Zarzo, J

    1997-03-03

    The effect of ethylenediaminetetraacetic acid (EDTA) on the heat resistance of Clostridium sporogenes PA 3679 spores was studied. EDTA was added to heating substrates and recovery media in order to establish which stage of the heat treatment registered the greatest EDTA activity. The heating substrates assayed were phosphate buffer (pH 7.0) and white asparagus purée, at natural pH (5.8) and acidified with citric acid and glucono-delta-lactone (GDL) to pH 5.5, 5.0 and 4.5. Recovery of survivors was carried out in MPA3679A medium in various conditions of acidification with citric and GDL (250 and 500 ppm), at pH 7.5 6.5 and 6.0. The results show greater activity of EDTA on spores when it was applied in recovery of heat injured spores, than during heating. The strongest influence of EDTA during heating was found in phosphate buffer (pH 7.0), with the effect being most evident at 121 and 126 degrees C, and in asparagus purée, at 121 degrees C and pH 5.8 rather than acidified. In recovery, the inhibiting activity of EDTA was more evident in spores subjected to more severe heat treatment, either by increasing the exposure time or by raising the temperature to 130 or 135 degrees C. The pH level of the recovery medium also affected the antimicrobial activity of EDTA, which had a greater inhibiting effect at pH 7.5 than at lower pH levels (6.5, 6.0).

  2. Esterase activity as a novel parameter of spore germination in Bacillus anthracis

    International Nuclear Information System (INIS)

    Ferencko, Linda; Cote, Mindy A.; Rotman, Boris

    2004-01-01

    Spores of Bacillus anthracis were shown to produce esterase activity about 4 min after exposure to conventional germinants such as combinations of amino acids and purine ribosides. Neither amino acids nor ribosides alone induce germination and esterase activity. Expression of esterase activity was chloramphenicol resistant, and correlated with loss of spore refractivity, a traditional parameter of early germination. Based on these observations, we hypothesized that esterase activity could be used as a novel parameter for quantifying early events during spore germination. To test this hypothesis, we measured expression of esterase activity under a variety of germinating conditions. Using diacetyl fluorescein as fluorogenic substrate of esterases, we demonstrated that esterase activity was invariably induced whenever spores were triggered by known germinants. Moreover, D-alanine, an inhibitor of L-alanine-mediated germination, was found to significantly inhibit expression of esterase activity. In terms of molecular mechanisms, esterase expression could represent activation of proteases at the onset of spore germination

  3. Germination and Inactivation of Alicyclobacillus acidoterrestris Spores Induced by Moderate Hydrostatic Pressure.

    Science.gov (United States)

    Sokołowska, Barbara; Skapska, Sylwia; Fonberg-Broczek, Monika; Niezgoda, Jolanta; Porebska, Izabela; Dekowska, Agnieszka; Rzoska, Sylwester J

    2015-01-01

    Given the importance of spoilage caused by Alicyclobacillus acidoterrestris for the fruit juice industry, the objective of this work was to study the germination and inactivation of A. acidoterrestris spores induced by moderate hydrostatic pressure. Hydrostatic pressure treatment can induce the germination and inactivation of A. acidoterrestris spores. At low pH, spore germination of up to 3.59-3.75 log and inactivation of 1.85-2.04 log was observed in a low pressure window (200-300 MPa) applied at 50 degrees C for 20 min. Neutral pH suppressed inactivation, the number of spores inactivated at pH 7.0 was only 0.24-1.06 log. The pressurization temperature significantly affected spore germination and inactivation. The degree of germination in apple juice after pressurization for 30 min with 200 MPa at 20 degrees C was 2.04 log, with only 0.61 log of spores being inactivated, while at 70 degrees C spore germination was 5.94 log and inactivation 4.72 log. This temperature strongly stimulated germination and inactivation under higher (500 MPa) than lower (200 MPa) pressure. When the oscillatory mode was used, the degree of germination and inactivation was slightly higher than at continuous mode. The degree of germination and inactivation was inversely proportional to the soluble solids content and was lowest in concentrated apple juice.

  4. The acid solubility test of clay mineral under microwave

    International Nuclear Information System (INIS)

    Zheng Ying; Niu Yuqing; Wu Peisheng; Niu Xuejun

    2001-01-01

    The acid solubility test of Al 3+ in clay from some uranium ores under microwave is introduced. The result shows that the concentration of Al 3+ in solution and the acid consumption increase rapidly under microwave comparing with normal leaching condition. It is infeasible to adopt microwave slacking method for intensively leaching uranium from uranium ore containing more clay

  5. A Clostridium difficile alanine racemase affects spore germination and accommodates serine as a substrate.

    Science.gov (United States)

    Shrestha, Ritu; Lockless, Steve W; Sorg, Joseph A

    2017-06-23

    Clostridium difficile has become one of the most common bacterial pathogens in hospital-acquired infections in the United States. Although C. difficile is strictly anaerobic, it survives in aerobic environments and transmits between hosts via spores. C. difficile spore germination is triggered in response to certain bile acids and glycine. Although glycine is the most effective co-germinant, other amino acids can substitute with varying efficiencies. Of these, l-alanine is an effective co-germinant and is also a germinant for most bacterial spores. Many endospore-forming bacteria embed alanine racemases into their spore coats, and these enzymes are thought to convert the l-alanine germinant into d-alanine, a spore germination inhibitor. Although the C. difficile Alr2 racemase is the sixth most highly expressed gene during C. difficile spore formation, a previous study reported that Alr2 has little to no role in germination of C. difficile spores in rich medium. Here, we hypothesized that Alr2 could affect C. difficile l-alanine-induced spore germination in a defined medium. We found that alr2 mutant spores more readily germinate in response to l-alanine as a co-germinant. Surprisingly, d-alanine also functioned as a co-germinant. Moreover, we found that Alr2 could interconvert l- and d-serine and that Alr2 bound to l- and d-serine with ∼2-fold weaker affinity to that of l- and d-alanine. Finally, we demonstrate that l- and d-serine are also co-germinants for C. difficile spores. These results suggest that C. difficile spores can respond to a diverse set of amino acid co-germinants and reveal that Alr2 can accommodate serine as a substrate. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Protection of Bacillus pumilus spores by catalases.

    Science.gov (United States)

    Checinska, Aleksandra; Burbank, Malcolm; Paszczynski, Andrzej J

    2012-09-01

    Bacillus pumilus SAFR-032, isolated at spacecraft assembly facilities of the National Aeronautics and Space Administration Jet Propulsion Laboratory, is difficult to kill by the sterilization method of choice, which uses liquid or vapor hydrogen peroxide. We identified two manganese catalases, YjqC and BPUM_1305, in spore protein extracts of several B. pumilus strains by using PAGE and mass spectrometric analyses. While the BPUM_1305 catalase was present in six of the B. pumilus strains tested, YjqC was not detected in ATCC 7061 and BG-B79. Furthermore, both catalases were localized in the spore coat layer along with laccase and superoxide dismutase. Although the initial catalase activity in ATCC 7061 spores was higher, it was less stable over time than the SAFR-032 enzyme. We propose that synergistic activity of YjqC and BPUM_1305, along with other coat oxidoreductases, contributes to the enhanced resistance of B. pumilus spores to hydrogen peroxide. We observed that the product of the catalase reaction, gaseous oxygen, forms expanding vesicles on the spore surface, affecting the mechanical integrity of the coat layer, resulting in aggregation of the spores. The accumulation of oxygen gas and aggregations may play a crucial role in limiting further exposure of Bacilli spore surfaces to hydrogen peroxide or other toxic chemicals when water is present.

  7. CO2 Solubilities in Amide-based Brφnsted Acidic Ionic Liquids

    International Nuclear Information System (INIS)

    Palgunadi, Jelliarko; Im, Jin Kyu; Kang, Je Eun; Kim, Hoon Sik; Cheong, Min Serk

    2010-01-01

    A distinguished class of hydrophobic ionic liquids bearing a Brφnsted acidic character derived from amide-like compounds were prepared by a neutralization reaction of N,N-diethylformamide, N,N-dibutylformamide, 1-formylpiperidine, and ε-caprolactam with trifluoroacetic acid and physical absorptions of CO 2 in these ionic liquids were demonstrated and evaluated. CO 2 solubilities in these ionic liquids were influenced by the molecular structure of the cation and were apparently increased with the molar volume. Comparison based on a volume unit reveals that CO 2 solubilities in these liquids are relatively higher than those in imidazolium-based ionic liquids. Henry's coefficients calculated from low-pressure solubility tests at 313 to 333 K were used to derive the thermodynamics quantities. Enthalpy and entropy of solvation may share equal contributions in solubility

  8. Chasing equilibrium: measuring the intrinsic solubility of weak acids and bases.

    Science.gov (United States)

    Stuart, Martin; Box, Karl

    2005-02-15

    A novel procedure is described for rapid (20-80 min) measurement of intrinsic solubility values of organic acids, bases, and ampholytes. In this procedure, a quantity of substance was first dissolved at a pH where it exists predominantly in its ionized form, and then a precipitate of the neutral (un-ionized) species was formed by changing the pH. Subsequently, the rate of change of pH due to precipitation or dissolution was monitored and strong acid and base titrant were added to adjust the pH to discover its equilibrium conditions, and the intrinsic solubility of the neutral form of the compound could then be determined. The procedure was applied to a variety of monoprotic and diprotic pharmaceutical compounds. The results were highly repeatable and had a good correlation to available published values. Data collected during the procedure provided good diagnostic information. Kinetic solubility data were also collected but provided a poor guide to the intrinsic solubility.

  9. Thermodynamic Solubility Profile of Carbamazepine-Cinnamic Acid Cocrystal at Different pH.

    Science.gov (United States)

    Keramatnia, Fatemeh; Shayanfar, Ali; Jouyban, Abolghasem

    2015-08-01

    Pharmaceutical cocrystal formation is a direct way to dramatically influence physicochemical properties of drug substances, especially their solubility and dissolution rate. Because of their instability in the solution, thermodynamic solubility of cocrystals could not be determined in the common way like other compounds; therefore, the thermodynamic solubility is calculated through concentration of their components in the eutectic point. The objective of this study is to investigate the effect of an ionizable coformer in cocrystal with a nonionizable drug at different pH. Carbamazepine (CBZ), a nonionizable drug with cinnamic acid (CIN), which is an acidic coformer, was selected to prepare CBZ-CIN cocrystal and its thermodynamic solubility was studied in pH range 2-7. Instead of HPLC that is a costly and time-consuming method, a chemometric-based approach, net analyte signal standard addition method, was selected for simultaneous determination of CBZ and CIN in solution. The result showed that, as pH increases, CIN ionization leads to change in CBZ-CIN cocrystal solubility and stability in solution. In addition, the results of this study indicated that there is no significant difference between intrinsic solubility of CBZ and cocrystal despite the higher ideal solubility of cocrystal. This verifies that ideal solubility is not good parameter to predict cocrystal solubility. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  10. An estimation of influence of humic acid and organic matter originated from bentonite on samarium solubility

    International Nuclear Information System (INIS)

    Kanaji, Mariko; Sato, Haruo; Sasahira, Akira

    1999-10-01

    Organic acids in groundwater are considered to form complexes and increase the solubility of radionuclides released from vitrified waste in a high-level radioactive waste (HLW) repository. To investigate whether the solubility of samarium (Sm) is influenced by organic substances, we measured Sm solubility in the presence of different organic substances and compared those values with results from thermodynamic predictions. Humic acid (Aldrich) is commercially available and soluble organic matter originated from bentonite were used as organic substances in this study. Consequently, the solubility of Sm showed a tendency to apparently increase with increasing the concentration of humic acid, but in the presence of carbonate, thermodynamic predictions suggested that the dominant species are carbonate complexes and that the effect of organic substances are less than that of carbonate. Based on total organic carbon (TOC), the increase of Sm solubility measured with humic acid (Aldrich) was more significant than that in the case with soluble organic matter originated from bentonite. Since bentonite is presumed to include also simple organic matters of which stability constant for forming complexes is low, the effect of soluble organic matter originated from bentonite on the solubility of Sm is considered to be less effective than that of humic acid (Aldrich). Experimental values were compared with model prediction, proposed by Kim, based on data measured in a low pH region. Tentatively we calculated the increase in Sm solubility assuming complexation with humic acid. Trial calculations were carried out on the premise that the complexation reaction of metal ion with humic acid is based on neutralization process by 1-1 complexation. In this process, it was assumed that one metal ion coordinates with one unit of complexation sites which number of proton exchange sites is equal to ionic charge. Consequently, Kim's model indicated that carbonate complexes should be dominant

  11. Spore Coat Architecture of Clostridium novyi-NT spores

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; McCafferey, J; Cheong, I; Huang, X; Bettegowda, C; Kinzler, K; Zhou, S; Vogelstein, B; Malkin, A

    2007-05-07

    Spores of the anaerobic bacterium Clostridium novyi-NT are able to germinate in and destroy hypoxic regions of tumors in experimental animals. Future progress in this area will benefit from a better understanding of the germination and outgrowth processes that are essential for the tumorilytic properties of these spores. Towards this end, we have used both transmission electron microscopy and atomic force microscopy to determine the structure of dormant as well as germinating spores. We found that the spores are surrounded by an amorphous layer intertwined with honeycomb parasporal layers. Moreover, the spore coat layers had apparently self-assembled and this assembly was likely to be governed by crystal growth principles. During germination and outgrowth, the honeycomb layers as well as the underlying spore coat and undercoat layers sequentially dissolved until the vegetative cell was released. In addition to their implications for understanding the biology of C. novyi-NT, these studies document the presence of proteinaceous growth spirals in a biological organism.

  12. Characterization of Wet-Heat Inactivation of Single Spores of Bacillus Species by Dual-Trap Raman Spectroscopy and Elastic Light Scattering▿

    Science.gov (United States)

    Zhang, Pengfei; Kong, Lingbo; Setlow, Peter; Li, Yong-qing

    2010-01-01

    Dual-trap laser tweezers Raman spectroscopy (LTRS) and elastic light scattering (ELS) were used to investigate dynamic processes during high-temperature treatment of individual spores of Bacillus cereus, Bacillus megaterium, and Bacillus subtilis in water. Major conclusions from these studies included the following. (i) After spores of all three species were added to water at 80 to 90°C, the level of the 1:1 complex of Ca2+ and dipicolinic acid (CaDPA; ∼25% of the dry weight of the spore core) in individual spores remained relatively constant during a highly variable lag time (Tlag), and then CaDPA was released within 1 to 2 min. (ii) The Tlag values prior to rapid CaDPA release and thus the times for wet-heat killing of individual spores of all three species were very heterogeneous. (iii) The heterogeneity in kinetics of wet-heat killing of individual spores was not due to differences in the microscopic physical environments during heat treatment. (iv) During the wet-heat treatment of spores of all three species, spore protein denaturation largely but not completely accompanied rapid CaDPA release, as some changes in protein structure preceded rapid CaDPA release. (v) Changes in the ELS from individual spores of all three species were strongly correlated with the release of CaDPA. The ELS intensities of B. cereus and B. megaterium spores decreased gradually and reached minima at T1 when ∼80% of spore CaDPA was released, then increased rapidly until T2 when full CaDPA release was complete, and then remained nearly constant. The ELS intensity of B. subtilis spores showed similar features, although the intensity changed minimally, if at all, prior to T1. (vi) Carotenoids in B. megaterium spores' inner membranes exhibited two changes during heat treatment. First, the carotenoid's two Raman bands at 1,155 and 1,516 cm−1 decreased rapidly to a low value and to zero, respectively, well before Tlag, and then the residual 1,155-cm−1 band disappeared, in parallel

  13. Effects of gamma irradiation on physicochemical properties of heat-induced gel prepared with chicken salt-soluble proteins

    International Nuclear Information System (INIS)

    Choi, Yun-Sang; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Seo, Kwang-Wook; Kim, Young-Boong; Kim, Cheon-Jei

    2015-01-01

    The technological effects of gamma irradiation (0, 3, 7, and 10 kGy) on chicken salt-soluble meat proteins in a model system were investigated. There were no significant differences in protein, fat, and ash content, and sarcoplasmic protein solubility among all samples. The samples with increasing gamma irradiation levels had higher pH, lightness, yellowness, and apparent viscosity, whereas moisture content, water holding capacity, redness, myofibrillar protein solubility, total protein solubility, hardness, springiness, cohesiveness, gumminess, and chewiness were the highest in the unirradiated control. The result from meat products using gamma irradiation was intended to provide a basic resource processing technology. - Highlights: • The effect of gamma irradiation on salt-soluble meat proteins was investigated. • Gelling properties of salt-soluble protein affected by gamma irradiation. • Gamma irradiation of meat products provides a basic resource processing technology

  14. Ionic liquid-assisted solublization for improved enzymatic esterification of phenolic acids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    2012-01-01

    in a binary system, which is composed of ionic liquid tOMA•TFA (trioctylmethylammonium Trifluoroacetate) and octanol. Ionic liquid tOMA•TFA has great solubility towards most of phenolic acid. The strategy of increasing the solubility of phenolic in ionic liquid tOMA•TFA was proved to be an efficient way...... for increasing conversion of phenolic acids. The mixture ratio between tOMA•TFA and octanol was varied from 1:4 to 1:16 (v/v), it was found that the highest conversion of dihydrocaffeic acid (DHCA) was achieved when tOMA•TFA and octanol was mixed as 1:12 (v/v). It was also found that conversion of DHCA at 70 o...

  15. Changes in protein solubility, fermentative capacity, viscoelasticity ...

    African Journals Online (AJOL)

    Frozen dough should be stored for fewer than 21 days; time in which the loaf volume of bread made from frozen dough was approximately 40.84% smaller than that of fresh bread dough formulation. Keywords: French type bread, frozen dough, protein solubility, baking quality, viscoelasticity. African Journal of Biotechnology ...

  16. Anomalous Solubility Behavior of Several Acidic Drugs

    Directory of Open Access Journals (Sweden)

    Alex Avdeef

    2014-04-01

    Full Text Available The “anomalous solubility behavior at higher pH values” of several acidic drugs originally studied by Higuchi et al. in 1953 [1], but hitherto not fully rationalized, has been re-analyzed using a novel solubility-pH analysis computer program, pDISOL-XTM. The program internally derives implicit solubility equations, given a set of proposed equilibria and constants (iteratively refined by weighted nonlinear regression, and does not require explicit Henderson-Hasselbalch equations. The re-analyzed original barbital, phenobarbital, oxytetracycline, and sulfathiazole solubility-pH data of Higuchi et al. is consistent with the presence of dimers in saturated solutions. In the case of barbital, phenobarbital and sulfathiazole, anionic dimers, reaching peak concentrations near pH 8. However, oxytetracycline indicated a pronounced tendency to form a cationic dimer, peaking near pH 2. Under the conditions of the original study, only barbital indicated a slight tendency to form a salt precipitate at pH > 6.8, with a highly unusual stoichiometry (consistent with a slope of 0.55 in the log S – pH plot: K+ + A2H- + 3HA D KA5H4(s. Thus the “anomaly” in the Higuchi data can be rationalized by invoking specific aggregated species.

  17. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with atmospheric ... molecular weight carboxylic acids in aerosol samples collected from a rural ... include biomass burning, agriculture, livestock and soil dust. Tropical ...

  18. The PsB glycoprotein complex is secreted as a preassembled precursor of the spore coat in Dictyostelium discoideum.

    Science.gov (United States)

    Watson, N; McGuire, V; Alexander, S

    1994-09-01

    The PsB glycoprotein in Dictyostelium discoideum is one of a diverse group of developmentally regulated, prespore-cell-specific proteins, that contain a common O-linked oligosaccharide. This post-translational modification is dependent on the wild-type modB allele. The PsB protein exists as part of a multiprotein complex of six different proteins, which have different post-translational modifications and are held together by both covalent and non-covalent interactions (Watson et al. (1993). J. Biol. Chem. 268, 22634-22641). In this study we have used microscopic and biochemical analyses to examine the cellular localization and function of the PsB complex during development. We found that the PsB complex first accumulates in prespore vesicles in slug cells and is secreted later during culmination and becomes localized to both the extracellular matrix of the apical spore mass of mature fruiting bodies and to the inner layer of the spore coat. The PsB associated with the spore coat is covalently bound by disulfide bridges. The PsB protein always exists in a multiprotein complex, but the composition of the PsB complex changes during secretion and spore maturation. Some of the PsB complex proteins have been identified as spore coat proteins. These data demonstrate that some of the proteins that form the spore coat exist as a preassembled precursor complex. The PsB complex is secreted in a developmentally regulated manner during the process of spore differentiation, at which time proteins of the complex, as well as additional spore coat proteins, become covalently associated in at least two forms of extracellular matrix: the interspore matrix and the spore coat. These and other studies show that proteins with modB dependent O-linked oligosaccharides are involved in a wide variety of processes underlying morphogenesis in this organism. These developmental processes are the direct result of cellular mechanisms regulating protein targeting, assembly and secretion, and the

  19. A two-step transport pathway allows the mother cell to nurture the developing spore in Bacillus subtilis.

    Science.gov (United States)

    Ramírez-Guadiana, Fernando H; Meeske, Alexander J; Rodrigues, Christopher D A; Barajas-Ornelas, Rocío Del Carmen; Kruse, Andrew C; Rudner, David Z

    2017-09-01

    One of the hallmarks of bacterial endospore formation is the accumulation of high concentrations of pyridine-2,6-dicarboxylic acid (dipicolinic acid or DPA) in the developing spore. This small molecule comprises 5-15% of the dry weight of dormant spores and plays a central role in resistance to both wet heat and desiccation. DPA is synthesized in the mother cell at a late stage in sporulation and must be translocated across two membranes (the inner and outer forespore membranes) that separate the mother cell and forespore. The enzymes that synthesize DPA and the proteins required to translocate it across the inner forespore membrane were identified over two decades ago but the factors that transport DPA across the outer forespore membrane have remained mysterious. Here, we report that SpoVV (formerly YlbJ) is the missing DPA transporter. SpoVV is produced in the mother cell during the morphological process of engulfment and specifically localizes in the outer forespore membrane. Sporulating cells lacking SpoVV produce spores with low levels of DPA and cells engineered to express SpoVV and the DPA synthase during vegetative growth accumulate high levels of DPA in the culture medium. SpoVV resembles concentrative nucleoside transporters and mutagenesis of residues predicted to form the substrate-binding pocket supports the idea that SpoVV has a similar structure and could therefore function similarly. These findings provide a simple two-step transport mechanism by which the mother cell nurtures the developing spore. DPA produced in the mother cell is first translocated into the intermembrane space by SpoVV and is then imported into the forespore by the SpoVA complex. This pathway is likely to be broadly conserved as DPA synthase, SpoVV, and SpoVA proteins can be found in virtually all endospore forming bacteria.

  20. Elastic and inelastic light scattering from single bacterial spores in an optical trap allows the monitoring of spore germination dynamics

    Science.gov (United States)

    Peng, Lixin; Chen, De; Setlow, Peter; Li, Yong-qing

    2009-01-01

    Raman scattering spectroscopy and elastic light scattering intensity (ESLI) were used to simultaneously measure levels of Ca-dipicolinic acid (CaDPA) and changes in spore morphology and refractive index during germination of individual B. subtilis spores with and without the two redundant enzymes (CLEs), CwlJ and SleB, that degrade spores’ peptidoglycan cortex. Conclusions from these measurements include: 1) CaDPA release from individual wild-type germinating spores was biphasic; in a first heterogeneous slow phase, Tlag, CaDPA levels decreased ∼15% and in the second phase ending at Trelease, remaining CaDPA was released rapidly; 2) in L-alanine germination of wild-type spores and spores lacking SleB: a) the ESLI rose ∼2-fold shortly before Tlag at T1; b) following Tlag, the ESLI again rose ∼2-fold at T2 when CaDPA levels had decreased ∼50%; and c) the ESLI reached its maximum value at ∼Trelease and then decreased; 3) in CaDPA germination of wild-type spores: a) Tlag increased and the first increase in ESLI occurred well before Tlag, consistent with different pathways for CaDPA and L-alanine germination; b) at Trelease the ESLI again reached its maximum value; 4) in L-alanine germination of spores lacking both CLEs and unable to degrade their cortex, the time ΔTrelease (Trelease–Tlag) for excretion of ≥75% of CaDPA was ∼15-fold higher than that for wild-type or sleB spores; and 5) spores lacking only CwlJ exhibited a similar, but not identical ESLI pattern during L-alanine germination to that seen with cwlJ sleB spores, and the high value for ΔTrelease. PMID:19374431

  1. Antimicrobial and Antifungal Effects of Acid and Water-Soluble Chitosan Extracted from Indian Shrimp (Fenneropenaeus indicus Shell

    Directory of Open Access Journals (Sweden)

    Ali Taheri

    2013-06-01

    Full Text Available Background & Objective : Currently, efforts are underway to seek new and effective antimicrobial agents, and marine resources are potent candidates for this aim. The following study was conducted to investigate the efficacy of water-soluble and acid-soluble chitosan against some pathogenic organisms.   Materials & Method s: Inhibition zone of different concentrations (5, 7.5, and 10 mg/ml of acid- soluble and water-soluble chitosan were examined for in vitro antibacterial activity against 4 kinds of hospital bacteria and penicillium sp. Results were compared with 4 standard antibiotics: streptomycin, gentamicin, tetracycline, and erythromycin. Furthermore, minimum inhibitory concentration and minimum lethal concentration were determined.   Results: Inhibition activity of acid-soluble chitosan (10% showed the best result (p value < 0.05, whereas water-soluble chitosan exhibited the least antibacterial effects (p value < 0.05. Chitosan demonstrated maximum effect on V. cholera cerotype ogava , and the least effect was seen on E. coli (p value < 0.05. Acid-soluble chitosan had a more potent effect than the standard antibiotics. Also, acid-soluble chitosan (10% and water-soluble chitosan showed maximum inhibitory effects on penicillium sp.   Conclusion: Chitosan showed maximum antibacterial effect against S. aureus, V. cholerae cerotype ogava, and water-soluble chitosan demonstrated good antifungal effects, revealing a statistically significant difference with common antibacterial and antifungal medicines.

  2. Synthesis and properties of amino acid functionalized water-soluble perylene diimides

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yongshan; Li, Xuemei; Wei, Xiaofeng; Jiang, Tianyi; Wu, Junsen; Ren, Huixue [Shandong Jianzhu University, Jinan (China)

    2015-07-15

    We prepared amino acid functionalized water-soluble perylene diimides: N,N'-bi(L-glutamic acid)-perylene-3,4;9,10-dicarboxylic diimide (1), N,N'-bi(L-phenylalanine acid)-perylene-3,4;9,10-dicarboxylic diimide (2), N,N'-bi(Lglutamic amine)-perylene-3,4;9,10-dicarboxylic diimide (3) and N,N'-bi(L-phenylalanine amine)-perylene-3,4;9,10-dicarboxylic diimide (4). The structures of 3 and 4 were confirmed by {sup 1}H NMR, FT-IR and MS. The maximal absorption bands of compound 1 and 2 in concentrated sulfuric acid were red-shifted for about 48 and 74 nm, respectively, compared with that of Perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCDA). Nearly no fluorescence was observed for compounds 1 and 2 in water, while compounds 3 and 4 were significantly water-soluble and had very high fluorescent quantum. The mechanism of the optical properties change was discussed, and the π-π stacking caused by H{sup +} led to the changes of fluorescence spectrum and absorption spectrum. The calculated molecular orbital energies and the frontier molecular orbital maps of compounds 1-2 based on density function theory (DFT) calculations were reported. Owing to the high water-soluble, the perylene derivatives 3 and 4 were successfully applied as high-performance fluorochromes for living hela cells imaging.

  3. Discrimination of Spore-Forming Bacilli Using spoIVA

    Science.gov (United States)

    Venkateswaran, Kasthuri; LaDuc, Myron; Stuecker, Tara

    2009-01-01

    A method of discriminating between spore-forming and non-spore-forming bacteria is based on a combination of simultaneous sporulation-specific and non-sporulation-specific quantitative polymerase chain reactions (Q-PCRs). The method was invented partly in response to the observation that for the purposes of preventing or reducing biological contamination affecting many human endeavors, ultimately, only the spore-forming portions of bacterial populations are the ones that are problematic (or, at least, more problematic than are the non-spore-forming portions). In some environments, spore-forming bacteria constitute small fractions of the total bacterial populations. The use of sporulation-specific primers in Q-PCR affords the ability to assess the spore-forming fraction of a bacterial population present in an environment of interest. This assessment can provide a more thorough and accurate understanding of the bacterial contamination in the environment, thereby making it possible to focus contamination- testing, contamination-prevention, sterilization, and decontamination resources more economically and efficiently. The method includes the use of sporulation-specific primers in the form of designed, optimized deoxyribonucleic acid (DNA) oligonucleotides specific for the bacterial spoIVA gene (see table). [In "spoIVA," "IV" signifies Roman numeral four and the entire quoted name refers to gene A for the fourth stage of sporulation.] These primers are mixed into a PCR cocktail with a given sample of bacterial cells. A control PCR cocktail into which are mixed universal 16S rRNA primers is also prepared. ["16S rRNA" denotes a ribosomal ribonucleic acid (rRNA) sequence that is common to all organisms.] Following several cycles of heating and cooling according to the PCR protocol to amplify amounts of DNA molecules, the amplification products can be analyzed to determine the types of bacterial cells present within the samples. If the amplification product is strong

  4. The MreB-like protein Mbl of Streptomyces coelicolor A3(2) depends on MreB for proper localization and contributes to spore wall synthesis.

    Science.gov (United States)

    Heichlinger, Andrea; Ammelburg, Moritz; Kleinschnitz, Eva-Maria; Latus, Annette; Maldener, Iris; Flärdh, Klas; Wohlleben, Wolfgang; Muth, Günther

    2011-04-01

    Most bacteria with a rod-shaped morphology contain an actin-like cytoskeleton consisting of MreB polymers, which form helical spirals underneath the cytoplasmic membrane to direct peptidoglycan synthesis for the elongation of the cell wall. In contrast, MreB of Streptomyces coelicolor is not required for vegetative growth but has a role in sporulation. Besides MreB, S. coelicolor encodes two further MreB-like proteins, Mbl and SCO6166, whose function is unknown. Whereas MreB and Mbl are highly similar, SCO6166 is shorter, lacking the subdomains IB and IIB of actin-like proteins. Here, we showed that MreB and Mbl are not functionally redundant but cooperate in spore wall synthesis. Expression analysis by semiquantitative reverse transcription-PCR revealed distinct expression patterns. mreB and mbl are induced predominantly during morphological differentiation. In contrast, sco6166 is strongly expressed during vegetative growth but switched off during sporulation. All genes could be deleted without affecting viability. Even a ΔmreB Δmbl double mutant was viable. Δsco6166 had a wild-type phenotype. ΔmreB, Δmbl, and ΔmreB Δmbl produced swollen, prematurely germinating spores that were sensitive to various kinds of stress, suggesting a defect in spore wall integrity. During aerial mycelium formation, an Mbl-mCherry fusion protein colocalized with an MreB-enhanced green fluorescent protein (MreB-eGFP) fusion protein at the sporulation septa. Whereas MreB-eGFP localized properly in the Δmbl mutant, Mbl-mCherry localization depended on the presence of a functional MreB protein. Our results revealed that MreB and Mbl cooperate in the synthesis of the thickened spore wall, while SCO6166 has a nonessential function during vegetative growth.

  5. Cytokine-like factor-1, a novel soluble protein, shares homology with members of the cytokine type I receptor family.

    Science.gov (United States)

    Elson, G C; Graber, P; Losberger, C; Herren, S; Gretener, D; Menoud, L N; Wells, T N; Kosco-Vilbois, M H; Gauchat, J F

    1998-08-01

    In this report we describe the identification, cloning, and expression pattern of human cytokine-like factor 1 (hCLF-1) and the identification and cloning of its murine homologue. They were identified from expressed sequence tags using amino acid sequences from conserved regions of the cytokine type I receptor family. Human CLF-1 and murine CLF-1 shared 96% amino acid identity and significant homology with many cytokine type I receptors. CLF-1 is a secreted protein, suggesting that it is either a soluble subunit within a cytokine receptor complex, like the soluble form of the IL-6R alpha-chain, or a subunit of a multimeric cytokine, e.g., IL-12 p40. The highest levels of hCLF-1 mRNA were observed in lymph node, spleen, thymus, appendix, placenta, stomach, bone marrow, and fetal lung, with constitutive expression of CLF-1 mRNA detected in a human kidney fibroblastic cell line. In fibroblast primary cell cultures, CLF-1 mRNA was up-regulated by TNF-alpha, IL-6, and IFN-gamma. Western blot analysis of recombinant forms of hCLF-1 showed that the protein has the tendency to form covalently linked di- and tetramers. These results suggest that CLF-1 is a novel soluble cytokine receptor subunit or part of a novel cytokine complex, possibly playing a regulatory role in the immune system and during fetal development.

  6. How cocrystals of weakly basic drugs and acidic coformers might modulate solubility and stability.

    Science.gov (United States)

    Kuminek, G; Rodríguez-Hornedo, N; Siedler, S; Rocha, H V A; Cuffini, S L; Cardoso, S G

    2016-04-30

    Cocrystals of a weakly basic drug (nevirapine) with acidic coformers are shown to alter the solubility dependence on pH, and to exhibit a pHmax above which a less soluble cocrystal becomes more soluble than the drug. The cocrystal solubility advantage can be dialed up or down by solution pH.

  7. Utilization of Condensed Distillers Solubles as Nutrient Supplement for Production of Nisin and Lactic Acid from Whey

    Science.gov (United States)

    Liu, Chuanbin; Hu, Bo; Chen, Shulin; Glass, Richard W.

    The major challenge associated with the rapid growth of the ethanol industry is the usage of the coproducts, i.e., condensed distillers solubles (CDS) and distillers dried grains, which are currently sold as animal feed supplements. As the growth of the livestock industries remains flat, alternative usage of these coproducts is urgently needed. CDS is obtained after the removal of ethanol by distillation from the yeast fermentation of a grain or a grain mixture by condensing the thin stillage fraction to semisolid. In this work, CDS was first characterized and yeast biomass was proven to be the major component of CDS. CDS contained 7.50% crude protein but with only 42% of that protein being water soluble. Then, CDS was applied as a nutrient supplement for simultaneous production of nisin and lactic acid by Lactococcus lactis subsp. lactis (ATCC 11454). Although CDS was able to support bacteria growth and nisin production, a strong inhibition was observed when CDS was overdosed. This may be caused by the existence of the major ethanol fermentation byproducts, especially lactate and acetate, in CDS. In the final step, the CDS based medium composition for nisin and lactic acid production was optimized using response surface methodology.

  8. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol-Water Mixtures

    NARCIS (Netherlands)

    Bowden, Nathan A.; Sanders, Johan P.M.; Bruins, Marieke E.

    2018-01-01

    The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization. We reviewed the available data on the solubility of α-amino acids in water, water-ethanol mixtures, and ethanol at 298.15 K and 0.1 MPa. The solubility of l-alanine, l-proline,

  9. Functional Properties and Amino Acid Profile of Spirulina Platensis Protein Isolates

    International Nuclear Information System (INIS)

    Bashir, S.; Sharif, M. K.; Butt, M. S.; Shahid, M.

    2016-01-01

    Protein malnutrition and food insecurity represent serious obstructions to sustainable development, poverty reduction and food quality throughout the world. The present study has been designed to evaluate the Spirulina platensis (SP) as a protein alternative source for the utilization in food products. A protein isolate was prepared from S. platensis powder through extraction with 0.1N NaOH, precipitation at pH 3, neutralization of the dispersed precipitate to pH 6.8-7.0, and subsequent freeze drying. The S. platensis isolate amino acids compositions revealed that the total essential amino acids contribution was comparatively higher in SPI (31.16±1.43 g/100 g) as compared with SP (27.75±1.21 g/100 g). Moreover, oil and water absorption capacities, foaming and emulsifying properties, surface hydrophobicity and nitrogen solubility index were found better functional properties under laboratory conditions except emulsion properties. Conclusively, SP and its isolates might be used in various food products to curtail protein energy malnutrition. (author)

  10. The MreB-Like Protein Mbl of Streptomyces coelicolor A3(2) Depends on MreB for Proper Localization and Contributes to Spore Wall Synthesis▿ †

    Science.gov (United States)

    Heichlinger, Andrea; Ammelburg, Moritz; Kleinschnitz, Eva-Maria; Latus, Annette; Maldener, Iris; Flärdh, Klas; Wohlleben, Wolfgang; Muth, Günther

    2011-01-01

    Most bacteria with a rod-shaped morphology contain an actin-like cytoskeleton consisting of MreB polymers, which form helical spirals underneath the cytoplasmic membrane to direct peptidoglycan synthesis for the elongation of the cell wall. In contrast, MreB of Streptomyces coelicolor is not required for vegetative growth but has a role in sporulation. Besides MreB, S. coelicolor encodes two further MreB-like proteins, Mbl and SCO6166, whose function is unknown. Whereas MreB and Mbl are highly similar, SCO6166 is shorter, lacking the subdomains IB and IIB of actin-like proteins. Here, we showed that MreB and Mbl are not functionally redundant but cooperate in spore wall synthesis. Expression analysis by semiquantitative reverse transcription-PCR revealed distinct expression patterns. mreB and mbl are induced predominantly during morphological differentiation. In contrast, sco6166 is strongly expressed during vegetative growth but switched off during sporulation. All genes could be deleted without affecting viability. Even a ΔmreB Δmbl double mutant was viable. Δsco6166 had a wild-type phenotype. ΔmreB, Δmbl, and ΔmreB Δmbl produced swollen, prematurely germinating spores that were sensitive to various kinds of stress, suggesting a defect in spore wall integrity. During aerial mycelium formation, an Mbl-mCherry fusion protein colocalized with an MreB-enhanced green fluorescent protein (MreB-eGFP) fusion protein at the sporulation septa. Whereas MreB-eGFP localized properly in the Δmbl mutant, Mbl-mCherry localization depended on the presence of a functional MreB protein. Our results revealed that MreB and Mbl cooperate in the synthesis of the thickened spore wall, while SCO6166 has a nonessential function during vegetative growth. PMID:21257777

  11. Effect of processing variables on the outgrowth of Clostridium sporogenes PA 3679 spores in comminuted meat cured with sorbic acid and sodium nitrite.

    Science.gov (United States)

    Robach, M C

    1979-11-01

    The effects of the initial pH and a "short pump" on the outgrowth of Clostridium sporogenes PA 3679 spores in comminuted cured pork were studied. Fresh ground pork was cured with salt, sugar, phosphate, ascorbate, and varying amounts of sodium nitrite and sorbic acid. The product was comminuted and inoculated with 1,000 spores of C. sporogenes per g. The meat was stuffed into 1-ounce (ca. 28.4-g) aluminum tubes, cooked to 58.5 degrees C, cooled, and incubated at 27 degrees C to observe for swells. Product cured with 0.2% sorbic acid in combination with 40 ppm sodium nitrite (40 microgram/g) had better clostridium inhibition than did product cured with 120 ppm nitrite within a pH range of 5.0 to 6.7. The sorbic acid-40 ppm nitrite combination also gave better clostridial protection than did the 120 ppm nitrite alone when reduced amounts of curing ingredients were present.

  12. Effect of processing variables on the outgrowth of Clostridium sporogenes PA 3679 spores in comminuted meat cured with sorbic acid and sodium nitrite.

    Science.gov (United States)

    Robach, M C

    1979-01-01

    The effects of the initial pH and a "short pump" on the outgrowth of Clostridium sporogenes PA 3679 spores in comminuted cured pork were studied. Fresh ground pork was cured with salt, sugar, phosphate, ascorbate, and varying amounts of sodium nitrite and sorbic acid. The product was comminuted and inoculated with 1,000 spores of C. sporogenes per g. The meat was stuffed into 1-ounce (ca. 28.4-g) aluminum tubes, cooked to 58.5 degrees C, cooled, and incubated at 27 degrees C to observe for swells. Product cured with 0.2% sorbic acid in combination with 40 ppm sodium nitrite (40 microgram/g) had better clostridium inhibition than did product cured with 120 ppm nitrite within a pH range of 5.0 to 6.7. The sorbic acid-40 ppm nitrite combination also gave better clostridial protection than did the 120 ppm nitrite alone when reduced amounts of curing ingredients were present. PMID:44445

  13. Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats.

    Directory of Open Access Journals (Sweden)

    Aude Lafoux

    Full Text Available Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17-19 months of age. An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents.

  14. Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats.

    Science.gov (United States)

    Lafoux, Aude; Baudry, Charlotte; Bonhomme, Cécile; Le Ruyet, Pascale; Huchet, Corinne

    2016-01-01

    Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17-19 months of age). An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents.

  15. Oxalic acid complexes: Promising draw solutes for forward osmosis (FO) in protein enrichment

    KAUST Repository

    Ge, Qingchun; Chung, Neal Tai-Shung

    2015-01-01

    Highly soluble oxalic acid complexes (OACs) were synthesized through a one-pot reaction. The OACs exhibit excellent performance as draw solutes in FO processes with high water fluxes and negligible reverse solute fluxes. Efficient protein enrichment was achieved. The diluted OACs can be recycled via nanofiltration and are promising as draw solutes.

  16. Processing and fatty acid acylation of RAS1 and RAS2 proteins in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Fujiyama, A.; Tamanoi, F.

    1986-01-01

    The authors demonstrate the pathway for the biosynthesis of RAS1 and RAS2 gene products of Saccharomyces cerevisiae leading to their localization in membranes. The primary translation products of these genes are detected in a soluble fraction. Shortly after synthesis, these precursor molecules are converted to forms that migrate slightly faster than the precursor forms on a NaDodSO 4 /polyacrylamide gel. These processed proteins are further modified by fatty acid acylation, which is detected by [ 3 H]palmitic acid labeling. The acylated derivatives are found exclusively in cell membranes, indicating the translocation of the RAS proteins from cytosol to membranes during maturation process. The attached fatty acids can be released by mild alkaline hydrolysis, suggesting that the linkage between the fatty acid and the protein is an ester bond. The site of the modification by fatty acid is presumably localized to the COOH-terminal portion of the RAS proteins. Fraction of the membranes by sucrose gradient demonstrates that a majority of the fatty-acylated RAS proteins are localized in plasma membrane

  17. Nucleic acid labeling with [3H]orotic acid and nucleotide profile in rats in protein deprivation, enteral and parenteral essential amino acid administration, and 5-fluorouracil treatment

    International Nuclear Information System (INIS)

    Jakobsson, B.; el Hag, I.A.; Andersson, M.; Christensson, P.I.; Stenram, U.

    1990-01-01

    Rats were fed a 0% casein diet for 1 week, with or without enteral or parenteral administration of essential amino acids, or a 25% casein diet, in one group supplemented with 5-fluorouracil treatment. Ninety minutes before sacrifice the rats were given a tracer of [3H]orotic acid. Incorporation into the acid soluble fraction, RNA, and DNA was determined in liver, small intestine, bone marrow, and kidney. Nucleotide profile was examined in liver and intestine. Protein deficiency caused inter alia a decrease in body weight; a decrease in RNA/DNA ratio and an increase in the specific RNA labeling in liver and kidney; an altered nucleotide profile in the liver; an increase in the nucleotide/DNA and RNA/DNA ratios and a decrease in the specific labeling of the acid soluble fraction, RNA, and DNA in the bone marrow. These changes were prevented to the same extent by giving essential amino acids, either orally or intravenously. The minor changes in intestinal nucleotide profile in protein deprivation were prevented to a slightly larger extent by amino acids orally than parenterally. 5-Fluorouracil treatment gave a decrease in the RNA/DNA ratio in the liver and kidney but an increase in the nucleotide/DNA and RNA/DNA ratios in the bone marrow. Nucleotide profiles were unaltered. The amount of DNA per gram of tissue decreased in bone marrow and increased in kidney. Parenteral administration per se resulted in almost no changes

  18. Ferulic Acid Dehydrodimer and –Dehydrotrimer Profiles of Distillers Dried Grains with Solubles from Different Cereal Species

    DEFF Research Database (Denmark)

    Pedersen, Mads Brøgger; Bunzel, Mirko; Schäfer, Judith

    2015-01-01

    Ferulic acid dehydrodimers- (DFA) and trimers (TriFA) ester-linked to plant cell wall polymers may not only cross-link cell wall polysaccharides, but also other cell wall components including proteins and lignin, thus, enhancing the rigidity and potentially affect the enzymatic degradation...... of the plant cell wall. Corn-, wheat-, and mixed cereal distillers dried grains with solubles (DDGS) were investigated for composition of DFAs and TriFAs by reversed phase high performance liquid chromatography with ultra violet detection. Corn DDGS contained 5.3 and 5.9 times higher contents of total DFAs...... acid cross-links in the corn cell wall are presumably not modified during fermentation and DDGS processing....

  19. Electron Beam Irradiation Dose Dependently Damages the Bacillus Spore Coat and Spore Membrane

    Directory of Open Access Journals (Sweden)

    S. E. Fiester

    2012-01-01

    Full Text Available Effective control of spore-forming bacilli begs suitable physical or chemical methods. While many spore inactivation techniques have been proven effective, electron beam (EB irradiation has been frequently chosen to eradicate Bacillus spores. Despite its widespread use, there are limited data evaluating the effects of EB irradiation on Bacillus spores. To study this, B. atrophaeus spores were purified, suspended in sterile, distilled water, and irradiated with EB (up to 20 kGy. Irradiated spores were found (1 to contain structural damage as observed by electron microscopy, (2 to have spilled cytoplasmic contents as measured by spectroscopy, (3 to have reduced membrane integrity as determined by fluorescence cytometry, and (4 to have fragmented genomic DNA as measured by gel electrophoresis, all in a dose-dependent manner. Additionally, cytometry data reveal decreased spore size, increased surface alterations, and increased uptake of propidium iodide, with increasing EB dose, suggesting spore coat alterations with membrane damage, prior to loss of spore viability. The present study suggests that EB irradiation of spores in water results in substantial structural damage of the spore coat and inner membrane, and that, along with DNA fragmentation, results in dose-dependent spore inactivation.

  20. The differential effects of heat-shocking on the viability of spores from Bacillus anthracis, Bacillus subtilis, and Clostridium sporogenes after treatment with peracetic acid- and glutaraldehyde-based disinfectants.

    Science.gov (United States)

    March, Jordon K; Pratt, Michael D; Lowe, Chinn-Woan; Cohen, Marissa N; Satterfield, Benjamin A; Schaalje, Bruce; O'Neill, Kim L; Robison, Richard A

    2015-10-01

    This study investigated (1) the susceptibility of Bacillus anthracis (Ames strain), Bacillus subtilis (ATCC 19659), and Clostridium sporogenes (ATCC 3584) spores to commercially available peracetic acid (PAA)- and glutaraldehyde (GA)-based disinfectants, (2) the effects that heat-shocking spores after treatment with these disinfectants has on spore recovery, and (3) the timing of heat-shocking after disinfectant treatment that promotes the optimal recovery of spores deposited on carriers. Suspension tests were used to obtain inactivation kinetics for the disinfectants against three spore types. The effects of heat-shocking spores after disinfectant treatment were also determined. Generalized linear mixed models were used to estimate 6-log reduction times for each spore type, disinfectant, and heat treatment combination. Reduction times were compared statistically using the delta method. Carrier tests were performed according to AOAC Official Method 966.04 and a modified version that employed immediate heat-shocking after disinfectant treatment. Carrier test results were analyzed using Fisher's exact test. PAA-based disinfectants had significantly shorter 6-log reduction times than the GA-based disinfectant. Heat-shocking B. anthracis spores after PAA treatment resulted in significantly shorter 6-log reduction times. Conversely, heat-shocking B. subtilis spores after PAA treatment resulted in significantly longer 6-log reduction times. Significant interactions were also observed between spore type, disinfectant, and heat treatment combinations. Immediately heat-shocking spore carriers after disinfectant treatment produced greater spore recovery. Sporicidal activities of disinfectants were not consistent across spore species. The effects of heat-shocking spores after disinfectant treatment were dependent on both disinfectant and spore species. Caution must be used when extrapolating sporicidal data of disinfectants from one spore species to another. Heat

  1. Etching of polymers, proteins and bacterial spores by atmospheric pressure DBD plasma in air

    Science.gov (United States)

    Kuzminova, A.; Kretková, T.; Kylián, O.; Hanuš, J.; Khalakhan, I.; Prukner, V.; Doležalová, E.; Šimek, M.; Biederman, H.

    2017-04-01

    Many studies proved that non-equilibrium discharges generated at atmospheric pressure are highly effective for the bio-decontamination of surfaces of various materials. One of the key processes that leads to a desired result is plasma etching and thus the evaluation of etching rates of organic materials is of high importance. However, the comparison of reported results is rather difficult if impossible as different authors use diverse sources of atmospheric plasma that are operated at significantly different operational parameters. Therefore, we report here on the systematic study of the etching of nine different common polymers that mimic the different structures of more complicated biological systems, bovine serum albumin (BSA) selected as the model protein and spores of Bacillus subtilis taken as a representative of highly resistant micro-organisms. The treatment of these materials was performed by means of atmospheric pressure dielectric barrier discharge (DBD) sustained in open air at constant conditions. All tested polymers, BSA and spores, were readily etched by DBD plasma. However, the measured etching rates were found to be dependent on the chemical structure of treated materials, namely on the presence of oxygen in the structure of polymers.

  2. Effects of non-covalent interactions with 5-O-caffeoylquinic acid (chlorogenic acid) on the heat denaturation and solubility of globular proteins

    NARCIS (Netherlands)

    Prigent, S.V.E.; Gruppen, H.; Visser, A.J.W.G.; Koningsveld, G.A. van; Jong, G.A.H. de; Voragen, A.G.J.

    2003-01-01

    The non-covalent interactions between the monomeric phenolic compound chlorogenic acid (5-CQA) and bovine serum albumin (BSA), lysozyme, and α-lactalbumin were characterized, and their effect on protein properties was examined. 5-CQA had a low affinity for all three proteins, and these interactions

  3. Boric acid solubility in the presence of alkali metal nitrides

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, V G; Tsekhanskij, R S; Molodkin, A K; Sadetdinov, Sh V [Chuvashskij Gosudarstvennyj Univ., Cheboksary (USSR); Universitet Druzhby Narodov, Moscow (USSR))

    1983-01-01

    Methods of solubility and refractometry at 25 deg C have been applied to state that systems boric acid-lithium (sodium, potassium) nitrite-water are simple eutonic type systems. Nitrites salt in the acid and their lyotropic effect increases from lithium salt to potassium salt. The disclosed succession in change of the effect is determined by the character of cation hydration in the medium the acidic reaction of which is conditioned by boric acid polymerization and partial oxidation of nitrite ion into nitrate ion. Boric acid is salted out from solutions containing lithium and sodium cations with increase of nitrate ion.

  4. Boric acid solubility in the presence of alkali metal nitrides

    International Nuclear Information System (INIS)

    Skvortsov, V.G.; Tsekhanskij, R.S.; Molodkin, A.K.; Sadetdinov, Sh.V.

    1983-01-01

    Methods of solubility and refractometry at 25 deg C have been applied to state that systems boric acid-lithium (sodiUm, potassium) nitrite-water are simple eutonic type systems. Nitrites salt in the acid and their lyotropic effect increases from lithium salt to potassium salt. The disclosed succession in change of the effect is determined by the character of cation hydration in the medium the acidic reaction of which is conditioned by boric acid polymerization and partial oxidation of nitrite ion into nitrate ion Boric acid is salted out form solutions containing lithium and sodium cations with increase of nitrate ion

  5. Solubility of nicotinic acid in water, ethanol, acetone, diethyl ether, acetonitrile, and dimethyl sulfoxide

    International Nuclear Information System (INIS)

    Gonçalves, Elsa M.; Minas da Piedade, Manuel E.

    2012-01-01

    Highlights: ► We determined the solubility of nicotinic acid in six solvents by the gravimetric method. ► We found that, regardless of the solvent, the same monoclinic solid phase was in equilibrium with the solution. ► We determined the activity coefficients of nicotinic acid in the six solvents. ► We found that the solubility trends seem to be determined by the polarity and polarizability of the solvent. - Abstract: The mole fraction equilibrium solubility of nicotinic acid in six solvents (water, ethanol, dimethyl sulfoxide, acetone, acetonitrile and diethyl ether) differing in polarity, polarizability, and hydrogen-bonding ability, was determined over the temperature range (283 to 333) K, using the gravimetric method. The results obtained led to the solubility order dimethyl sulfoxide (DMSO) ≫ ethanol > water > acetone > diethyl ether > acetonitrile. An analysis based on various solvent descriptors, indicated that this trend seems to be mainly determined by the polarity and polarizability of the solvent. The activity coefficients of nicotinic acid in the different solvents, under saturation conditions, were determined as a function of the temperature and it was found that DMSO exhibits enhanced solubility relative to an ideal solution while the opposite is observed for all other solvents. Both the solvent and the fact that nicotinic acid is primarily zwitterionic in aqueous solution and non-zwitterionic in non-aqueous media, did not affect the nature of the solid phases in equilibrium with the different solutions. Indeed, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and differential scanning calorimetry analysis indicated that, despite some differences in particle size and morphology, the starting material and the solid products obtained at the end of the solubility studies in the six solvents used in this work were all crystalline and corresponded to the same monoclinic phase.

  6. Beetroot-pigment-derived colorimetric sensor for detection of calcium dipicolinate in bacterial spores.

    Directory of Open Access Journals (Sweden)

    Letícia Christina Pires Gonçalves

    Full Text Available In this proof-of-concept study, we describe the use of the main red beet pigment betanin for the quantification of calcium dipicolinate in bacterial spores, including Bacillus anthracis. In the presence of europium(III ions, betanin is converted to a water-soluble, non-luminescent orange 1∶1 complex with a stability constant of 1.4 × 10(5 L mol(-1. The addition of calcium dipicolinate, largely found in bacterial spores, changes the color of the aqueous solution of [Eu(Bn(+] from orange to magenta. The limit of detection (LOD of calcium dipicolinate is around 2.0 × 10(-6 mol L(-1 and the LOD determined for both spores, B. cereus and B. anthracis, is (1.1 ± 0.3× 10(6 spores mL(-1. This simple, green, fast and low cost colorimetric assay was selective for calcium dipicolinate when compared to several analogous compounds. The importance of this work relies on the potential use of betalains, raw natural pigments, as colorimetric sensors for biological applications.

  7. NanoSIMS analysis of Bacillus spores for forensics

    Energy Technology Data Exchange (ETDEWEB)

    Weber, P K; Davisson, M L; Velsko, S P

    2010-02-23

    The threat associated with the potential use of radiological, nuclear, chemical and biological materials in terrorist acts has resulted in new fields of forensic science requiring the application of state-of-the-science analytical techniques. Since the anthrax letter attacks in the United States in the fall of 2001, there has been increased interest in physical and chemical characterization of bacterial spores. While molecular methods are powerful tools for identifying genetic differences, other methods may be able to differentiate genetically identical samples based on physical and chemical properties, as well as provide complimentary information, such as methods of production and approximate date of production. Microanalysis has the potential to contribute significantly to microbial forensics. Bacillus spores are highly structured, consisting of a core, cortex, coat, and in some species, an exosporium. This structure provides a template for constraining elemental abundance differences at the nanometer scale. The primary controls on the distribution of major elements in spores are likely structural and physiological. For example, P and Ca are known to be abundant in the spore core because that is where P-rich nucleic acids and Cadipicolinic acid are located, respectively. Trace elements are known to bind to the spore coat but the controls on these elements are less well understood. Elemental distributions and abundances may be directly related to spore production, purification and stabilization methodologies, which are of particular interest for forensic investigation. To this end, we are developing a high-resolution secondary ion mass spectrometry method using a Cameca NanoSIMS 50 to study the distribution and abundance of trace elements in bacterial spores. In this presentation we will review and compare methods for preparing and analyzing samples, as well as review results on the distribution and abundance of elements in bacterial spores. We use NanoSIMS to

  8. Mechanism and site of inhibition of Bacillus cereus spore outgrowth by nitrosothiols

    International Nuclear Information System (INIS)

    Morris, S.L.

    1982-01-01

    Structure vs. activity studies demonstrate that nitrosothiols inhibit outgrowth of B. cereus spores by reversible covalent bond formation with sensitive spore components. Kinetic studies of the binding of nitrosothiols and iodoacetate, a known sulfhydryl reagent, show that they complete for the same spore sites. Since two other nitrite derivatives, the Perigo factor and the transferrin inhibitor, interfere with iodoacetate label uptake in a kinetically similar fashion, all of these compounds may inhibit spore outgrowth by interacting with the same spore thiol groups. Disruption of spores which have been inhibited by radioactive iodoacetate demonstrates that much of the label is incorporated into a membrane-rich fraction that sediments as a single peak on a sucrose density gradient. SDS gel electrophoresis and autofluorography allows the identification of four intensely labelled proteins with molecular weights of 13,000, 28,000, 29,000, and 30,000. If the iodoacetate labelling is carried out in the presence of nitrosothiol, incorporation is greatly reduced into all components. When germinating spores are labelled with succinate or the lactose analog, o-nitrophenylgalactopyranoside, a significant reduction in the amount of label bound is also observed suggesting that two iodoacetate-reactive sites may be the succinate and lactose permease systems. Severe decreases in the transport of succinate and lactose into iodoacetate and nitrosothiol inhibited spores further implicates a nitrosothiol (iodoacetate) permease interaction. Iodoacetate and nitrosothiols therefore may exert their inhibitory effects by interfering with critical membrane protein sulfhydryl groups, possibly by a a covalent modification mechanism. Some of these sensitive thiols may be involved in active transport processes

  9. Expression and display of UreA of Helicobacter acinonychis on the surface of Bacillus subtilis spores

    Directory of Open Access Journals (Sweden)

    De Felice Maurilio

    2010-01-01

    Full Text Available Abstract Background The bacterial endospore (spore has recently been proposed as a new surface display system. Antigens and enzymes have been successfully exposed on the surface layers of the Bacillus subtilis spore, but only in a few cases the efficiency of expression and the effective surface display and have been determined. We used this heterologous expression system to produce the A subunit of the urease of the animal pathogen Helicobater acinonychis. Ureases are multi-subunit enzymes with a central role in the virulence of various bacterial pathogens and necessary for colonization of the gastric mucosa by the human pathogen H. pylori. The urease subunit UreA has been recognized as a major antigen, able to induce high levels of protection against challenge infections. Results We expressed UreA from H. acinonychis on the B. subtilis spore coat by using three different spore coat proteins as carriers and compared the efficiency of surface expression and surface display obtained with the three carriers. A combination of western-, dot-blot and immunofluorescence microscopy allowed us to conclude that, when fused to CotB, UreA is displayed on the spore surface (ca. 1 × 103 recombinant molecules per spore, whereas when fused to CotC, although most efficiently expressed (7-15 × 103 recombinant molecules per spore and located in the coat layer, it is not displayed on the surface. Experiments with CotG gave results similar to those with CotC, but the CotG-UreA recombinant protein appeared to be partially processed. Conclusion UreA was efficiently expressed on the spore coat of B. subtilis when fused to CotB, CotC or CotG. Of these three coat proteins CotC allows the highest efficiency of expression, whereas CotB is the most appropriate for the display of heterologous proteins on the spore surface.

  10. Expression and display of UreA of Helicobacter acinonychis on the surface of Bacillus subtilis spores.

    Science.gov (United States)

    Hinc, Krzysztof; Isticato, Rachele; Dembek, Marcin; Karczewska, Joanna; Iwanicki, Adam; Peszyńska-Sularz, Grazyna; De Felice, Maurilio; Obuchowski, Michał; Ricca, Ezio

    2010-01-18

    The bacterial endospore (spore) has recently been proposed as a new surface display system. Antigens and enzymes have been successfully exposed on the surface layers of the Bacillus subtilis spore, but only in a few cases the efficiency of expression and the effective surface display and have been determined. We used this heterologous expression system to produce the A subunit of the urease of the animal pathogen Helicobater acinonychis. Ureases are multi-subunit enzymes with a central role in the virulence of various bacterial pathogens and necessary for colonization of the gastric mucosa by the human pathogen H. pylori. The urease subunit UreA has been recognized as a major antigen, able to induce high levels of protection against challenge infections. We expressed UreA from H. acinonychis on the B. subtilis spore coat by using three different spore coat proteins as carriers and compared the efficiency of surface expression and surface display obtained with the three carriers. A combination of western-, dot-blot and immunofluorescence microscopy allowed us to conclude that, when fused to CotB, UreA is displayed on the spore surface (ca. 1 x 10(3) recombinant molecules per spore), whereas when fused to CotC, although most efficiently expressed (7-15 x 10(3) recombinant molecules per spore) and located in the coat layer, it is not displayed on the surface. Experiments with CotG gave results similar to those with CotC, but the CotG-UreA recombinant protein appeared to be partially processed. UreA was efficiently expressed on the spore coat of B. subtilis when fused to CotB, CotC or CotG. Of these three coat proteins CotC allows the highest efficiency of expression, whereas CotB is the most appropriate for the display of heterologous proteins on the spore surface.

  11. Strategy to inactivate Clostridium perfringens spores in meat products.

    Science.gov (United States)

    Akhtar, Saeed; Paredes-Sabja, Daniel; Torres, J Antonio; Sarker, Mahfuzur R

    2009-05-01

    The current study aimed to develop an inactivation strategy for Clostridium perfringens spores in meat through a combination of spore activation at low pressure (100-200 MPa, 7 min) and elevated temperature (80 degrees C, 10 min); spore germination at high temperatures (55, 60 or 65 degrees C); and inactivation of germinated spores with elevated temperatures (80 and 90 degrees C, 10 and 20 min) and high pressure (586 MPa, at 23 and 73 degrees C, 10 min). Low pressures (100-200 MPa) were insufficient to efficiently activate C. perfringens spores for germination. However, C. perfringens spores were efficiently activated with elevated temperature (80 degrees C, 10 min), and germinated at temperatures lethal for vegetative cells (>or= 55 degrees C) when incubated for 60 min with a mixture of L-asparagine and KCl (AK) in phosphate buffer (pH 7) and in poultry meat. Inactivation of spores (approximately 4 decimal reduction) in meat by elevated temperatures (80-90 degrees C for 20 min) required a long germination period (55 degrees C for 60 min). However, similar inactivation level was reached with shorter germination period (55 degrees C for 15 min) when spore contaminated-meat was treated with pressure-assisted thermal processing (568 MPa, 73 degrees C, 10 min). Therefore, the most efficient strategy to inactivate C. perfringens spores in poultry meat containing 50 mM AK consisted: (i) a primary heat treatment (80 degrees C, 10 min) to pasteurize and denature the meat proteins and to activate C. perfringens spores for germination; (ii) cooling of the product to 55 degrees C in about 20 min and further incubation at 55 degrees C for about 15 min for spore germination; and (iii) inactivation of germinated spores by pressure-assisted thermal processing (586 MPa at 73 degrees C for 10 min). Collectively, this study demonstrates the feasibility of an alternative and novel strategy to inactivate C. perfringens spores in meat products formulated with germinants specific for C

  12. Handling technique of spore-forming bacteria in radiation sterilization. 1. Preparation of spores

    International Nuclear Information System (INIS)

    Koshikawa, Tomihiko

    1994-01-01

    This paper deals with a handling technique of spore-forming bacteria in radiation sterilization. An explanation is given under three sections: (1) life cycle of spore-forming bacteria, medium to form bacterial spores, and colony and purification methods of bacterial spores; (2) methods for measuring the number of bacterial spores and resistance against gamma radiation (D values); and (3) a test method for identifying spore-forming bacteria and a simple identification method. (N.K.)

  13. The "high solubility" definition of the current FDA Guidance on Biopharmaceutical Classification System may be too strict for acidic drugs.

    Science.gov (United States)

    Yazdanian, Mehran; Briggs, Katherine; Jankovsky, Corinne; Hawi, Amale

    2004-02-01

    The purpose of this study was to assess if the definition of high solubility as proposed in the FDA Guidance on Biopharmaceutical Classification System (BCS) is too strict for highly permeable acidic drugs. The solubility and permeability values of 20 (18 acidic and 2 non-acidic) nonsteroidal anti-inflammatory drugs (NSAID) were determined. The NSAIDs were grouped into three different sets having acetic acid, propionic acid, or other acidic moieties such as fenamate, oxicam, and salicylate. Two nonacidic NSAIDs (celecoxib and rofecoxib) were also included for comparison purposes. Equilibrium solubility values were determined at pH 1.2, 5.0, 7.4, and in biorelevant media simulating fed intestinal fluid at pH 5.0. For a select number of acids, we also measured solubility values in media simulating gastric and fasted intestinal fluids. Permeability classification was established relative to that of reference drugs in the Caco-2 cell permeability model. Permeability coefficients for all drugs were measured at concentrations corresponding to the lowest and highest marketed dose strengths dissolved in 250 ml volume, and their potential interaction with cellular efflux pumps was investigated. All NSAIDs with different acidic functional groups were classified as highly permeable based on their Caco-2 cell permeability. Only ketorolac appeared to have a potential for interaction with cellular efflux pumps. Solubility classification was based on comparison of equilibrium solubility at pH 1.2, 5.0. and 7.4 relative to marketed dose strengths in 250 ml. The pKa values for the acidic NSAIDs studied were between 3.5 and 5.1. and, as expected, their solubility increased dramatically at pH 7.4 compared to pH 1.2. Only three NSAIDs, ketorolac, ketoprofen. and acetyl salicylic acid, meet the current criteria for high solubility over the entire pH range. However, with the exception of ibuprofen, oxaprozin, and mefenamic acid, the remaining compounds can be classified as Class I drugs

  14. Screening of genetic parameters for soluble protein expression in Escherichia coli

    DEFF Research Database (Denmark)

    Vernet, Erik; Kotzsch, Alexander; Voldborg, Bjørn

    2011-01-01

    Soluble expression of proteins in a relevant form for functional and structural investigations still often remains a challenge. Although many biochemical factors are known to affect solubility, a thorough investigation of yield-limiting factors is normally not feasible in high-throughput efforts....... Here we present a screening strategy for expression of biomedically relevant proteins in Escherichia coli using a panel of six different genetic variations. These include engineered strains for rare codon supplementation, increased disulfide bond formation in the cytoplasm and novel vectors...... for secretion to the periplasm or culture medium. Combining these variants with expression construct truncations design, we report on parallel cloning and expression of more than 300 constructs representing 24 selected proteins; including full-length variants of human growth factors, interleukins and growth...

  15. CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

    Directory of Open Access Journals (Sweden)

    S. S. Hings

    2008-07-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (dm<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (dcore≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

  16. Plasmid-associated sensitivity of Bacillus thuringiensis to UV light

    International Nuclear Information System (INIS)

    Benoit, T.G.; Wilson, G.R.; Bull, D.L.; Aronson, A.I.

    1990-01-01

    Spores and vegetative cells of Bacillus thuringiensis were more sensitive to UV light than were spores or cells of plasmid-cured B. thuringiensis strains or of the closely related Bacillus cereus. Introduction of B. thuringiensis plasmids into B. cereus by cell mating increased the UV sensitivity of the cells and spores. Protoxins encoded by one or more B. thuringiensis plasmids were not involved in spore sensitivity, since a B. thuringiensis strain conditional for protoxin accumulation was equally sensitive at the permissive and nonpermissive temperatures. In addition, introduction of either a cloned protoxin gene, the cloning vector, or another plasmid not containing a protoxin gene into a plasmid-cured strain of B. thuringiensis all increased the UV sensitivity of the spores. Although the variety of small, acid-soluble proteins was the same in the spores of all strains examined, the quantity of dipicolinic acid was about twice as high in the plasmid-containing strains, and this may account for the differences in UV sensitivity of the spores. The cells of some strains harboring only B. thuringiensis plasmids were much more sensitive than cells of any of the other strains, and the differences were much greater than observed with spores

  17. High-Resolution Spore Coat Architecture and Assembly of Bacillus Spores

    Energy Technology Data Exchange (ETDEWEB)

    Malkin, A J; Elhadj, S; Plomp, M

    2011-03-14

    Elucidating the molecular architecture of bacterial and cellular surfaces and its structural dynamics is essential to understanding mechanisms of pathogenesis, immune response, physicochemical interactions, environmental resistance, and provide the means for identifying spore formulation and processing attributes. I will discuss the application of in vitro atomic force microscopy (AFM) for studies of high-resolution coat architecture and assembly of several Bacillus spore species. We have demonstrated that bacterial spore coat structures are phylogenetically and growth medium determined. We have proposed that strikingly different species-dependent coat structures of bacterial spore species are a consequence of sporulation media-dependent nucleation and crystallization mechanisms that regulate the assembly of the outer spore coat. Spore coat layers were found to exhibit screw dislocations and two-dimensional nuclei typically observed on inorganic and macromolecular crystals. This presents the first case of non-mineral crystal growth patterns being revealed for a biological organism, which provides an unexpected example of nature exploiting fundamental materials science mechanisms for the morphogenetic control of biological ultrastructures. We have discovered and validated, distinctive formulation-specific high-resolution structural spore coat and dimensional signatures of B. anthracis spores (Sterne strain) grown in different formulation condition. We further demonstrated that measurement of the dimensional characteristics of B. anthracis spores provides formulation classification and sample matching with high sensitivity and specificity. I will present data on the development of an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures on the B. anthracis surfaces. These studies demonstrate that AFM can probe microbial surface architecture, environmental dynamics and the life cycle of bacterial and cellular systems at near

  18. Assembly of an Oxalate Decarboxylase Produced under σK Control into the Bacillus subtilis Spore Coat

    Science.gov (United States)

    Costa, Teresa; Steil, Leif; Martins, Lígia O.; Völker, Uwe; Henriques, Adriano O.

    2004-01-01

    Over 30 polypeptides are synthesized at various times during sporulation in Bacillus subtilis, and they are assembled at the surface of the developing spore to form a multilayer protein structure called the coat. The coat consists of three main layers, an amorphous undercoat close to the underlying spore cortex peptidoglycan, a lamellar inner layer, and an electron-dense striated outer layer. The product of the B. subtilis oxdD gene was previously shown to have oxalate decarboxylase activity when it was produced in Escherichia coli and to be a spore constituent. In this study, we found that OxdD specifically associates with the spore coat structure, and in this paper we describe regulation of its synthesis and assembly. We found that transcription of oxdD is induced during sporulation as a monocistronic unit under the control of σK and is negatively regulated by GerE. We also found that localization of a functional OxdD-green fluorescent protein (GFP) at the surface of the developing spore depends on the SafA morphogenetic protein, which localizes at the interface between the spore cortex and coat layers. OxdD-GFP localizes around the developing spore in a cotE mutant, which does not assemble the spore outer coat layer, but it does not persist in spores produced by the mutant. Together, the data suggest that OxdD-GFP is targeted to the interior layers of the coat. Additionally, we found that expression of a multicopy allele of oxdD resulted in production of spores with increased levels of OxdD that were able to degrade oxalate but were sensitive to lysozyme. PMID:14973022

  19. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar ‘203Z’ and its near-isogenic line (NIL) ‘SW’ (in the ‘203Z’ background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening. PMID:29324867

  20. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Directory of Open Access Journals (Sweden)

    Lei Gao

    Full Text Available Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL 'SW' (in the '203Z' background were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy, sucrose-phosphate synthase (SPSs, insoluble acid invertases (IAI, NAD-dependent malate dehydrogenase (NAD-cyt MDH, aluminum-activated malate transporter (ALMT, and citrate synthase (CS. This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  1. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling; Liu, Wenge

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL) 'SW' (in the '203Z' background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  2. Intrinsic solubility estimation and pH-solubility behavior of cosalane (NSC 658586), an extremely hydrophobic diprotic acid.

    Science.gov (United States)

    Venkatesh, S; Li, J; Xu, Y; Vishnuvajjala, R; Anderson, B D

    1996-10-01

    The selection of cosalane (NSC 658586) by the National Cancer Institute for further development as a potential drug candidate for the treatment of AIDS led to the exploration of the solubility behavior of this extremely hydrophobic drug, which has an intrinsic solubility (S0 approaching 1 ng/ml. This study describes attempts to reliably measure the intrinsic solubility of cosalane and examine its pH-solubility behavior. S0 was estimated by 5 different strategies: (a) direct determination in an aqueous suspension: (b) facilitated dissolution; (c) estimation from the octanol/water partition coefficient and octanol solubility (d) application of an empirical equation based on melting point and partition coefficient; and (e) estimation from the hydrocarbon solubility and functional group contributions for transfer from hydrocarbon to water. S0 estimates using these five methods varied over a 5 x 107-fold range Method (a) yielded the highest values, two-orders of magnitude greater than those obtained by method (b) (facilitated dissolution. 1.4 +/- 0.5 ng/ml). Method (c) gave a value 20-fold higher while that from method (d) was in fair agreement with that from facilitated dissolution. Method (e) yielded a value several orders-of-magnitude lower than other methods. A molecular dynamics simulation suggests that folded conformations not accounted for by group contributions may reduce cosalane's effective hydrophobicity. Ionic equilibria calculations for this weak diprotic acid suggested a 100-fold increase in solubility per pH unit increase. The pH-solubility profile of cosalane at 25 degrees C agreed closely with theory. These studies highlight the difficulty in determining solubility of very poorly soluble compounds and the possible advantage of the facilitated dissolution method. The diprotic nature of cosalane enabled a solubility enhancement of > 107-fold by simple pH adjustment.

  3. Factors influencing the inactivation of Alicyclobacillus acidoterrestris spores exposed to high hydrostatic pressure in apple juice

    Science.gov (United States)

    Sokołowska, B.; Skąpska, S.; Fonberg-Broczek, M.; Niezgoda, J.; Chotkiewicz, M.; Dekowska, A.; Rzoska, S. J.

    2013-03-01

    Alicyclobacillus acidoterrestris, a thermoacidophilic and spore-forming bacterium, survives the typical pasteurization process and can cause the spoilage of juices, producing compounds associated with disinfectant-like odour (guaiacol, 2,6 - dibromophenol, 2,6 - dichlorophenol). Therefore, the use of other more effective techniques such as high hydrostatic pressure (HHP) is considered for preserving juices. The aim of this study was to search for factors affecting the resistance of A. acidoterrestris spores to HHP. The baroprotective effect of increased solute concentration in apple juice on A. acidoterrestris spores during high pressure processing was observed. During the 45 min pressurization (200 MPa, 50°C) of the spores in concentrated apple juice (71.1°Bx), no significant changes were observed in their number. However, in the juices with a soluble solids content of 35.7, 23.6 and 11.2°Bx, the reduction in spores was 1.3-2.4 log, 2.6-3.3 log and 2.8-4.0 log, respectively. No clear effect of age of spores on the survival under high pressure conditions was found. Spores surviving pressurization and subjected to subsequent HHP treatment showed increased resistance to pressure, by even as much as 2.0 log.

  4. Unique Features of Halophilic Proteins.

    Science.gov (United States)

    Arakawa, Tsutomu; Yamaguchi, Rui; Tokunaga, Hiroko; Tokunaga, Masao

    2017-01-01

    Proteins from moderate and extreme halophiles have unique characteristics. They are highly acidic and hydrophilic, similar to intrinsically disordered proteins. These characteristics make the halophilic proteins soluble in water and fold reversibly. In addition to reversible folding, the rate of refolding of halophilic proteins from denatured structure is generally slow, often taking several days, for example, for extremely halophilic proteins. This slow folding rate makes the halophilic proteins a novel model system for folding mechanism analysis. High solubility and reversible folding also make the halophilic proteins excellent fusion partners for soluble expression of recombinant proteins.

  5. Solubility of iron from combustion source particles in acidic media linked to iron speciation.

    Science.gov (United States)

    Fu, Hongbo; Lin, Jun; Shang, Guangfeng; Dong, Wenbo; Grassian, Vichi H; Carmichael, Gregory R; Li, Yan; Chen, Jianmin

    2012-10-16

    In this study, iron solubility from six combustion source particles was investigated in acidic media. For comparison, a Chinese loess (CL) dust was also included. The solubility experiments confirmed that iron solubility was highly variable and dependent on particle sources. Under dark and light conditions, the combustion source particles dissolved faster and to a greater extent relative to CL. Oil fly ash (FA) yielded the highest soluble iron as compared to the other samples. Total iron solubility fractions measured in the dark after 12 h ranged between 2.9 and 74.1% of the initial iron content for the combustion-derived particles (Oil FA > biomass burning particles (BP) > coal FA). Ferrous iron represented the dominant soluble form of Fe in the suspensions of straw BP and corn BP, while total dissolved Fe presented mainly as ferric iron in the cases of oil FA, coal FA, and CL. Mössbauer measurements and TEM analysis revealed that Fe in oil FA was commonly presented as nanosized Fe(3)O(4) aggregates and Fe/S-rich particles. Highly labile source of Fe in corn BP could be originated from amorphous Fe form mixed internally with K-rich particles. However, Fe in coal FA was dominated by the more insoluble forms of both Fe-bearing aluminosilicate glass and Fe oxides. The data presented herein showed that iron speciation varies by source and is an important factor controlling iron solubility from these anthropogenic emissions in acidic solutions, suggesting that the variability of iron solubility from combustion-derived particles is related to the inherent character and origin of the aerosols themselves. Such information can be useful in improving our understanding on iron solubility from combustion aerosols when they undergo acidic processing during atmospheric transport.

  6. Preferential inclusion of extrachromosomal genetic elements in yeast meiotic spores.

    Science.gov (United States)

    Brewer, B J; Fangman, W L

    1980-09-01

    During meiosis and sporulation in the yeast Saccharomyces cerevisiae, extrachromosomal traits are efficiently transmitted to haploid spores. Although the pattern of inheritance of chromosomal traits reflects the mechanism of regular chromosomal segregation in meiosis, it is not known what processes are reflected by the efficient inheritance of extrachromosomal traits. Because extrachromosomal genetic elements in yeast are present in multiple copies, perpetuation of an extrachromosomal trait could occur by the passive envelopment of a subset of copies or by an active sequestering of all or a subset of copies within the four spores. We show that only subsets of the four extrachromosomal nucleic acids commonly found in yeast are transmitted through meiosis--55% of mitochondrial DNA copies, 82% of the 2-micron DNA plasmids, and about 70% of the L and M double-stranded RNAs. However, electron micrographs of serial sections through yeast asci indicate that the four spore enclose only 30% of the total ascus material. Thus these extrachromosomal elements are preferentially included within the spores, indicating that their inheritance is not a random process. Transmission of mitochondrial DNA can be accounted for by the observed enclosure of 52% of the mitochondrial volume within the spores. The high transmission frequencies of the double-stranded RNAs (which exist as virus-like particles in the cytoplasm) and 2-micron DNA must indicate that either these nucleic acids are actively recruited from the cytoplasm by some mechanism or they are associated in some way with the nucleus during meiosis.

  7. Factor VII and protein C are phosphatidic acid-binding proteins.

    Science.gov (United States)

    Tavoosi, Narjes; Smith, Stephanie A; Davis-Harrison, Rebecca L; Morrissey, James H

    2013-08-20

    Seven proteins in the human blood clotting cascade bind, via their GLA (γ-carboxyglutamate-rich) domains, to membranes containing exposed phosphatidylserine (PS), although with membrane binding affinities that vary by 3 orders of magnitude. Here we employed nanodiscs of defined phospholipid composition to quantify the phospholipid binding specificities of these seven clotting proteins. All bound preferentially to nanobilayers in which PS headgroups contained l-serine versus d-serine. Surprisingly, however, nanobilayers containing phosphatidic acid (PA) bound substantially more of two of these proteins, factor VIIa and activated protein C, than did equivalent bilayers containing PS. Consistent with this finding, liposomes containing PA supported higher proteolytic activity by factor VIIa and activated protein C toward their natural substrates (factors X and Va, respectively) than did PS-containing liposomes. Moreover, treating activated human platelets with phospholipase D enhanced the rates of factor X activation by factor VIIa in the presence of soluble tissue factor. We hypothesize that factor VII and protein C bind preferentially to the monoester phosphate of PA because of its accessibility and higher negative charge compared with the diester phosphates of most other phospholipids. We further found that phosphatidylinositol 4-phosphate, which contains a monoester phosphate attached to its myo-inositol headgroup, also supported enhanced enzymatic activity of factor VIIa and activated protein C. We conclude that factor VII and protein C bind preferentially to monoester phosphates, which may have implications for the function of these proteases in vivo.

  8. Recent progress in Bacillus subtilis spore-surface display: concept, progress, and future.

    Science.gov (United States)

    Wang, He; Wang, Yunxiang; Yang, Ruijin

    2017-02-01

    With the increased knowledge on spore structure and advances in biotechnology engineering, the newly developed spore-surface display system confers several inherent advantages over other microbial cell-surface display systems including enhanced stability and high safety. Bacillus subtilis is the most commonly used Bacillus species for spore-surface display. The expression of heterologous antigen or protein on the surface of B. subtilis spores has now been practiced for over a decade with noteworthy success. As an update and supplement to other previous reviews, we comprehensively summarize recent studies in the B. subtilis spore-surface display technique. We focus on its benefits as well as the critical factors affecting its display efficiency and offer suggestions for the future success of this field.

  9. Amino Acid Composition, Molecular Weight Distribution and Gel Electrophoresis of Walnut (Juglans regia L. Proteins and Protein Fractionations

    Directory of Open Access Journals (Sweden)

    Xiaoying Mao

    2014-01-01

    Full Text Available As a by-product of oil production, walnut proteins are considered as an additional source of plant protein for human food. To make full use of the protein resource, a comprehensive understanding of composition and characteristics of walnut proteins are required. Walnut proteins have been fractionated and characterized in this study. Amino acid composition, molecular weight distribution and gel electrophoresis of walnut proteins and protein fractionations were analyzed. The proteins were sequentially separated into four fractions according to their solubility. Glutelin was the main component of the protein extract. The content of glutelin, albumin, globulin and prolamin was about 72.06%, 7.54%, 15.67% and 4.73% respectively. Glutelin, albumin and globulin have a balanced content of essential amino acids, except for methionine, with respect to the FAO pattern recommended for adults. SDS-PAGE patterns of albumin, globulin and glutelin showed several polypeptides with molecular weights 14.4 to 66.2 kDa. The pattern of walnut proteins in two-dimension electrophoresis (2-DE showed that the isoelectric point was mainly in the range of 4.8–6.8. The results of size exclusion chromatogram indicated molecular weight of the major components of walnut proteins were between 3.54 and 81.76 kDa.

  10. Acid-base equilibria and solubility of loratadine and desloratadine in water and micellar media.

    Science.gov (United States)

    Popović, Gordana; Cakar, Mira; Agbaba, Danica

    2009-01-15

    Acid-base equilibria in homogeneous and heterogeneous systems of two antihistaminics, loratadine and desloratadine were studied spectrophotometrically in Britton-Robinson's buffer at 25 degrees C. Acidity constant of loratadine was found to be pK(a) 5.25 and those of desloratadine pK(a1) 4.41 and pK(a2) 9.97. The values of intrinsic solubilities of loratadine and desloratadine were 8.65x10(-6) M and 3.82x10(-4) M, respectively. Based on the pK(a) values and intrinsic solubilities, solubility curves of these two drugs as a function of pH were calculated. The effects of anionic, cationic and non-ionic surfactants applied in the concentration exceeding critical micelle concentration (cmc) on acid-base properties of loratadine and desloratadine, as well as on intrinsic solubility of loratadine were also examined. The results revealed a shift of pK(a) values in micellar media comparing to the values obtained in water. These shifts (DeltapK(a)) ranged from -2.24 to +1.24.

  11. Immunochemical analyses of soluble lens proteins in some marine fishes

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.

    Soluble eye lens proteins of 10 fishes, belonging to the families Clupeidae, Hemirhamphidae, Lactaridae, Scombridae, Stromatidae, Psettodidae, Bothidae and Soleidae were studied by immunoelectrophoresis using the lens antiserum of Sardinella...

  12. Investigation of Sterilization Mechanism for Geobacillus stearothermophilus Spores with Plasma-Excited Neutral Gas

    Science.gov (United States)

    Matsui, Kei; Ikenaga, Noriaki; Sakudo, Noriyuki

    2015-09-01

    We investigate the mechanism of the sterilization with plasma-excited neutral gas that uniformly sterilizes both the space and inner wall of the reactor chamber at atmospheric pressure. Only reactive neutral species such as plasma-excited gas molecules and radicals are separated from the plasma and sent to the reactor chamber for chemical sterilization. The plasma source gas uses humidified mixture of nitrogen and oxygen. Geobacillus stearothermophilus spores and tyrosine which is amino acid are treated by the plasma-excited neutral gas. Shape change of the treated spore is observed by SEM, and chemical modification of the treated tyrosine is analyzed by HPLC. As a result, the surface of the treated spore shows depression. Hydroxylation and nitration of tyrosine are shown after the treatment. For these reasons, we believe that the sterilization with plasma-excited neutral gas results from the deformation of spore structure due to the chemical modification of amino acid.

  13. Spore-to-spore agar culture of the myxomycete Physarum globuliferum.

    Science.gov (United States)

    Liu, Pu; Wang, Qi; Li, Yu

    2010-02-01

    The ontogeny of the myxomycete Physarum globuliferum was observed on corn meal agar and hanging drop cultures without adding sterile oat flakes, bacteria or other microorganisms. Its complete life cycle including spore germination, myxamoebae, swarm cells, plasmodial development, and maturity of fructifications was demonstrated. Details of spore-to-spore development are described and illustrated.

  14. Production and characterization of cowpea protein hydrolysate with optimum nitrogen solubility by enzymatic hydrolysis using pepsin.

    Science.gov (United States)

    Mune Mune, Martin Alain; Minka, Samuel René

    2017-06-01

    Cowpea is a source of low-cost and good nutritional quality protein for utilization in food formulations in replacement of animal proteins. Therefore it is necessary that cowpea protein exhibits good functionality, particularly protein solubility which affects the other functional properties. The objective of this study was to produce cowpea protein hydrolysate exhibiting optimum solubility by the adequate combination of hydrolysis parameters, namely time, solid/liquid ratio (SLR) and enzyme/substrate ratio (ESR), and to determine its functional properties and molecular characteristics. A Box-Behnken experimental design was used for the experiments, and a second-order polynomial to model the effects of hydrolysis time, SLR and ESR on the degree of hydrolysis and nitrogen solubility index. The optimum hydrolysis conditions of time 208.61 min, SLR 1/15 (w/w) and ESR 2.25% (w/w) yielded a nitrogen solubility of 75.71%. Protein breakdown and the peptide profile following enzymatic hydrolysis were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and size exclusion chromatography. Cowpea protein hydrolysate showed higher oil absorption capacity, emulsifying activity and foaming ability compared with the concentrate. The solubility of cowpea protein hydrolysate was adequately optimized by response surface methodology, and the hydrolysate showed adequate functionality for use in food. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. Formation of the outer layer of the Dictyostelium spore coat depends on the inner-layer protein SP85/PsB.

    Science.gov (United States)

    Metcalf, Talibah; Kelley, Karen; Erdos, Gregory W; Kaplan, Lee; West, Christopher M

    2003-02-01

    The Dictyostelium spore is surrounded by a 220 microm thick trilaminar coat that consists of inner and outer electron-dense layers surrounding a central region of cellulose microfibrils. In previous studies, a mutant strain (TL56) lacking three proteins associated with the outer layer exhibited increased permeability to macromolecular tracers, suggesting that this layer contributes to the coat permeability barrier. Electron microscopy now shows that the outer layer is incomplete in the coats of this mutant and consists of a residual regular array of punctate electron densities. The outer layer is also incomplete in a mutant lacking a cellulose-binding protein associated with the inner layer, and these coats are deficient in an outer-layer protein and another coat protein. To examine the mechanism by which this inner-layer protein, SP85, contributes to outer-layer formation, various domain fragments were overexpressed in forming spores. Most of these exert dominant negative effects similar to the deletion of outer-layer proteins, but one construct, consisting of a fusion of the N-terminal and Cys-rich C1 domain, induces a dense mat of novel filaments at the surface of the outer layer. Biochemical studies show that the C1 domain binds cellulose, and a combination of site-directed mutations that inhibits its cellulose-binding activity suppresses outer-layer filament induction. The results suggest that, in addition to a previously described early role in regulating cellulose synthesis, SP85 subsequently contributes a cross-bridging function between cellulose and other coat proteins to organize previously unrecognized structural elements in the outer layer of the coat.

  16. Structural Characterization of Lipopeptides Isolated from Bacillus Globigii Spores

    National Research Council Canada - National Science Library

    Williams, Bruce

    2001-01-01

    .... Bacillus globigil spores, grown in new sporulation media (NSM), were suspended and then analyzed using a MALDI-TOF mass spectrometer to screen for biomarkers with 4-methoxycinnamic acid as matrix...

  17. Carvacrol suppresses high pressure high temperature inactivation of Bacillus cereus spores.

    Science.gov (United States)

    Luu-Thi, Hue; Corthouts, Jorinde; Passaris, Ioannis; Grauwet, Tara; Aertsen, Abram; Hendrickx, Marc; Michiels, Chris W

    2015-03-16

    The inactivation of bacterial spores generally proceeds faster and at lower temperatures when heat treatments are conducted under high pressure, and high pressure high temperature (HPHT) processing is, therefore, receiving an increased interest from food processors. However, the mechanisms of spore inactivation by HPHT treatment are poorly understood, particularly at moderately elevated temperature. In the current work, we studied inactivation of the spores of Bacillus cereus F4430/73 by HPHT treatment for 5 min at 600MPa in the temperature range of 50-100°C, using temperature increments of 5°C. Additionally, we investigated the effect of the natural antimicrobial carvacrol on spore germination and inactivation under these conditions. Spore inactivation by HPHT was less than about 1 log unit at 50 to 70°C, but gradually increased at higher temperatures up to about 5 log units at 100°C. DPA release and loss of spore refractility in the spore population were higher at moderate (≤65°C) than at high (≥70°C) treatment temperatures, and we propose that moderate conditions induced the normal physiological pathway of spore germination resulting in fully hydrated spores, while at higher temperatures this pathway was suppressed and replaced by another mechanism of pressure-induced dipicolinic acid (DPA) release that results only in partial spore rehydration, probably because spore cortex hydrolysis is inhibited. Carvacrol strongly suppressed DPA release and spore rehydration during HPHT treatment at ≤65°C and also partly inhibited DPA release at ≥65°C. Concomitantly, HPHT spore inactivation was reduced by carvacrol at 65-90°C but unaffected at 95-100°C. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Directory of Open Access Journals (Sweden)

    Kevin eEgan

    2016-04-01

    Full Text Available Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB. Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural, approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable

  19. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Science.gov (United States)

    Egan, Kevin; Field, Des; Rea, Mary C; Ross, R Paul; Hill, Colin; Cotter, Paul D

    2016-01-01

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more

  20. Microemulsion formulation of clonixic acid: solubility enhancement and pain reduction.

    Science.gov (United States)

    Lee, Jung-Mi; Park, Kyung-Mi; Lim, Soo-Jeong; Lee, Mi-Kyung; Kim, Chong-Kook

    2002-01-01

    Clonixic acid is currently marketed as a salt form because of its poor water-solubility. However, the commercial dosage form causes severe pain after intramuscular or intravenous injection. To improve the solubility of clonixic acid and to reduce pain on injection, clonixic acid was incorporated into oil-in-water microemulsions prepared from pre-microemulsion concentrate composed of varying ratios of oil and surfactant mixture. As an oil phase for drug incorporation, up to 14% castor oil could be included in the pre-microemulsion concentrate without a significant increase in droplet size. Both drug contents and droplet size increased as the weight ratio of Tween 20 to Tween 85 decreased. Taken together, when microemulsions were prepared from pre-microemulsion concentrate composed of 5:12:18 weight ratio of castor oil:Tween 20:Tween 85, clonixic acid could be incorporated at 3.2 mg mL(-1) in the microemulsion with a droplet size of less than 120 nm. The osmotic pressure of this microemulsion was remarkably lower than the commercial formulation, irrespective of the dilution ratios. The rat paw-lick test was used to compare pain responses among formulations. The microemulsion formulation significantly reduced the number of rats licking their paws as well as the total licking time, suggesting less pain induction by the microemulsion formulation. The pharmacokinetic parameters of clonixic acid after intravenous administration of the clonixic acid microemulsion to rats were not significantly different from those of the commercial formulation, lysine clonixinate. The present study suggests that microemulsion is an alternative formulation for clonixic acid with improved characteristics.

  1. The characterisation of Bacillus spores occurring in the manufacturing of (low acid) canned products

    NARCIS (Netherlands)

    Oomes, S.J.C.M.; Zuijlen, A.C.M. van; Hehenkamp, J.O.; Witsenboer, H.; Vossen, J.M.B.M. van der; Brul, S.

    2007-01-01

    Spore-forming bacteria can be a problem in the food industry, especially in the canning industry. Spores present in ingredients or present in the processing environment severely challenge the preservation process since their thermal resistance may be very high. We therefore asked the question which

  2. Arbuscular mycorrhizal fungi spore propagation using single spore as starter inoculum and a plant host.

    Science.gov (United States)

    Selvakumar, G; Shagol, C C; Kang, Y; Chung, B N; Han, S G; Sa, T M

    2018-06-01

    The propagation of pure cultures of arbuscular mycorrhizal fungal (AMF) is an essential requirement for their large-scale agricultural application and commercialization as biofertilizers. The present study aimed to propagate AMF using the single-spore inoculation technique and compare their propagation ability with the known reference spores. Arbuscular mycorrhizal fungal spores were collected from salt-affected Saemangeum reclaimed soil in South Korea. The technique involved inoculation of sorghum-sudangrass (Sorghum bicolor L.) seedlings with single, healthy spores on filter paper followed by the transfer of successfully colonized seedlings to 1-kg capacity pots containing sterilized soil. After the first plant cycle, the contents were transferred to 2·5-kg capacity pots containing sterilized soil. Among the 150 inoculated seedlings, only 27 seedlings were colonized by AMF spores. After 240 days, among the 27 seedlings, five inoculants resulted in the production of over 500 spores. The 18S rDNA sequencing of spores revealed that the spores produced through single-spore inoculation method belonged to Gigaspora margarita, Claroideoglomus lamellosum and Funneliformis mosseae. Furthermore, indigenous spore F. mosseae M-1 reported a higher spore count than the reference spores. The AMF spores produced using the single-spore inoculation technique may serve as potential bio-inoculants with an advantage of being more readily adopted by farmers due to the lack of requirement of a skilled technique in spore propagation. The results of the current study describe the feasible and cost-effective method to mass produce AMF spores for large-scale application. The AMF spores obtained from this method can effectively colonize plant roots and may be easily introduced to the new environment. © 2018 The Society for Applied Microbiology.

  3. Recent Progress in the Development of Supercritical Carbon Dioxide-Soluble Metal Ion Extractants: Aggregation, Extraction, and Solubility Properties of Silicon-Substituted Alkylenediphosphonic Acids

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Mark L.; McAlister, Daniel R.; Stepinski, Dominique C.; Zalupski, Peter R.; Dzilawa, Julie A.; Barrans, Richard E.; Hess, J.N.; Rubas, Audris V.; Chiarizia, Renato; Lubbers, Christopher M.; Scurto, Aaron M.; Brennecke, Joan F.; Herlinger, Albert W.

    2003-09-11

    Partially esterified alkylenediphosphonic acids (DPAs) have been shown to be effective reagents for the extraction of actinide ions from acidic aqueous solution into conventional organic solvents. Efforts to employ these compounds in supercritical fluid extraction have been hampered by their modest solubility in unmodified supercritical carbon dioxide (SC-CO2). In an effort to design DPAs that are soluble in SC-CO2, a variety of silicon-substituted alkylenediphosphonic acids have been prepared and characterized, and their behavior compared with that of conventional alkyl-substituted reagents. Silicon substitution is shown to enhance the CO2-philicity of the reagents, while other structural features, in particular, the number of methylene groups bridging the phosphorus atoms of the extractant, are shown to exert a significant influence on their aggregation and extraction properties. The identification of DPAs combining desirable extraction properties with adequate solubility in SC-CO2 is shown to be facilitated by the application of molecular connectivity indices.

  4. Effective non-denaturing purification method for improving the solubility of recombinant actin-binding proteins produced by bacterial expression.

    Science.gov (United States)

    Chung, Jeong Min; Lee, Sangmin; Jung, Hyun Suk

    2017-05-01

    Bacterial expression is commonly used to produce recombinant and truncated mutant eukaryotic proteins. However, heterologous protein expression may render synthesized proteins insoluble. The conventional method used to express a poorly soluble protein, which involves denaturation and refolding, is time-consuming and inefficient. There are several non-denaturing approaches that can increase the solubility of recombinant proteins that include using different bacterial cell strains, altering the time of induction, lowering the incubation temperature, and employing different detergents for purification. In this study, we compared several non-denaturing protocols to express and purify two insoluble 34 kDa actin-bundling protein mutants. The solubility of the mutant proteins was not affected by any of the approaches except for treatment with the detergent sarkosyl. These results indicate that sarkosyl can effectively improve the solubility of insoluble proteins during bacterial expression. Copyright © 2016. Published by Elsevier Inc.

  5. PCR detection of thermophilic spore-forming bacteria involved in canned food spoilage.

    Science.gov (United States)

    Prevost, S; Andre, S; Remize, F

    2010-12-01

    Thermophilic bacteria that form highly heat-resistant spores constitute an important group of spoilage bacteria of low-acid canned food. A PCR assay was developed in order to rapidly trace these bacteria. Three PCR primer pairs were designed from rRNA gene sequences. These primers were evaluated for the specificity and the sensitivity of detection. Two primer pairs allowed detection at the species level of Geobacillus stearothermophilus and Moorella thermoacetica/thermoautrophica. The other pair allowed group-specific detection of anaerobic thermophilic bacteria of the genera Thermoanaerobacterium, Thermoanaerobacter, Caldanerobium and Caldanaerobacter. After a single enrichment step, these PCR assays allowed the detection of 28 thermophiles from 34 cans of spoiled low-acid food. In addition, 13 ingredients were screened for the presence of these bacteria. This PCR assay serves as a detection method for strains able to spoil low-acid canned food treated at 55°C. It will lead to better reactivity in the canning industry. Raw materials and ingredients might be qualified not only for quantitative spore contamination, but also for qualitative contamination by highly heat-resistant spores.

  6. Spore formation and toxin production in Clostridium difficile biofilms.

    Science.gov (United States)

    Semenyuk, Ekaterina G; Laning, Michelle L; Foley, Jennifer; Johnston, Pehga F; Knight, Katherine L; Gerding, Dale N; Driks, Adam

    2014-01-01

    The ability to grow as a biofilm can facilitate survival of bacteria in the environment and promote infection. To better characterize biofilm formation in the pathogen Clostridium difficile, we established a colony biofilm culture method for this organism on a polycarbonate filter, and analyzed the matrix and the cells in biofilms from a variety of clinical isolates over several days of biofilm culture. We found that biofilms readily formed in all strains analyzed, and that spores were abundant within about 6 days. We also found that extracellular DNA (eDNA), polysaccharide and protein was readily detected in the matrix of all strains, including the major toxins A and/or B, in toxigenic strains. All the strains we analyzed formed spores. Apart from strains 630 and VPI10463, which sporulated in the biofilm at relatively low frequencies, the frequencies of biofilm sporulation varied between 46 and 65%, suggesting that variations in sporulation levels among strains is unlikely to be a major factor in variation in the severity of disease. Spores in biofilms also had reduced germination efficiency compared to spores obtained by a conventional sporulation protocol. Transmission electron microscopy revealed that in 3 day-old biofilms, the outermost structure of the spore is a lightly staining coat. However, after 6 days, material that resembles cell debris in the matrix surrounds the spore, and darkly staining granules are closely associated with the spores surface. In 14 day-old biofilms, relatively few spores are surrounded by the apparent cell debris, and the surface-associated granules are present at higher density at the coat surface. Finally, we showed that biofilm cells possess 100-fold greater resistance to the antibiotic metronidazole then do cells cultured in liquid media. Taken together, our data suggest that C. difficile cells and spores in biofilms have specialized properties that may facilitate infection.

  7. Spore formation and toxin production in Clostridium difficile biofilms.

    Directory of Open Access Journals (Sweden)

    Ekaterina G Semenyuk

    Full Text Available The ability to grow as a biofilm can facilitate survival of bacteria in the environment and promote infection. To better characterize biofilm formation in the pathogen Clostridium difficile, we established a colony biofilm culture method for this organism on a polycarbonate filter, and analyzed the matrix and the cells in biofilms from a variety of clinical isolates over several days of biofilm culture. We found that biofilms readily formed in all strains analyzed, and that spores were abundant within about 6 days. We also found that extracellular DNA (eDNA, polysaccharide and protein was readily detected in the matrix of all strains, including the major toxins A and/or B, in toxigenic strains. All the strains we analyzed formed spores. Apart from strains 630 and VPI10463, which sporulated in the biofilm at relatively low frequencies, the frequencies of biofilm sporulation varied between 46 and 65%, suggesting that variations in sporulation levels among strains is unlikely to be a major factor in variation in the severity of disease. Spores in biofilms also had reduced germination efficiency compared to spores obtained by a conventional sporulation protocol. Transmission electron microscopy revealed that in 3 day-old biofilms, the outermost structure of the spore is a lightly staining coat. However, after 6 days, material that resembles cell debris in the matrix surrounds the spore, and darkly staining granules are closely associated with the spores surface. In 14 day-old biofilms, relatively few spores are surrounded by the apparent cell debris, and the surface-associated granules are present at higher density at the coat surface. Finally, we showed that biofilm cells possess 100-fold greater resistance to the antibiotic metronidazole then do cells cultured in liquid media. Taken together, our data suggest that C. difficile cells and spores in biofilms have specialized properties that may facilitate infection.

  8. Expression and Purification of Soluble STAT5b/STAT3 Proteins for SH2 Domain Binding Assay.

    Science.gov (United States)

    Asai, Akira; Takakuma, Kazuyuki

    2017-01-01

    When a large hydrophobic full-length protein is expressed in bacteria, it is often challenging to obtain recombinant proteins in the soluble fraction. One way to overcome this challenge is expression of deletion mutants that have improved solubility while maintaining biological activity. In this chapter, we describe a protocol for expression of truncated forms of STAT5b and STAT3 proteins that are soluble and retain SH2-mediated activity for phospho-Tyr peptide recognition.

  9. Modeling to control spores in raw milk

    NARCIS (Netherlands)

    Vissers, M.

    2007-01-01

    A modeling approach was used to identify measures at the farm that reduce transmission of microorganisms to raw milk. Butyric acid bacteria (BAB) and Bacillus cereus were used as case-studies. Minimizing the concentration of BAB spores in raw milk is important to prevent late-blowing of Gouda-type

  10. Investigations on uranyl nitrate solubility in nitric acid in different concentrations at temperatures of 50C

    International Nuclear Information System (INIS)

    Deigele, E.

    1983-01-01

    The solubility of uranyl nitrate was studied in nitric acid solutions of different concentrations at a temperature of 5 0 C. This temperature was chosen with a view to using water as coolant and to facilitate the handling of the strong acid solutions. Accurate curves were established by a multitude of accurate measurements in the high concentration range. Further solubility curves can be derived from this basic curve. Some of the precipitates in the interesting regions of the solubility curve were analyzed. (orig./EF) [de

  11. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    Atmospheric aerosol samples of PM2.5 and PM10 were collected in April–May 2011 from a rural site in Tanzania and analyzed for water-soluble inorganic ions and low molecular weight carboxylic acids using ion chromatography. PM2.5 and PM10 low-volume samplers with quartz fibre filters were deployed and aerosol ...

  12. Fluorescent detection of dipicolinic acid as a biomarker of bacterial spores using lanthanide-chelated gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Donmez, Mert [Department of Chemistry, Faculty of Art and Sciences, Duzce University, Duzce 81620 (Turkey); Yilmaz, M. Deniz, E-mail: deniz.yilmaz@gidatarim.edu.tr [Department of Bioengineering, Faculty of Engineering and Architecture, Konya Food and Agriculture University, Konya 42080 (Turkey); Kilbas, Benan, E-mail: benankilbas@duzce.edu.tr [Department of Chemistry, Faculty of Art and Sciences, Duzce University, Duzce 81620 (Turkey)

    2017-02-15

    Highlights: • The nanosensors based on gold nanoparticles functionalized with lanthanide complexes were synthesized. • The nanosensors selectively and sensitively detected DPA, a biomarker of bacterial spores. • Ratiometric sensing of DPA by a ternary complex was achieved by ligand displacement strategy. - Abstract: Gold nanoparticles (GNPs) functionalized with ethylenediamine-lanthanide complexes (Eu-GNPs and Tb-GNPs) were used for the selective fluorescent detection of dipicolinic acid (DPA), a unique biomarker of bacterial spores, in water. Particles were characterized by transmission electron microscopy and zeta potential measurements. The coordination of DPA to the lanthanides resulted in the enhancement of the fluorescence. A selective response to DPA was observed over the nonselective binding of aromatic ligands. The ligand displacement strategy were also employed for the ratiometric fluorescent detection of DPA. 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedion (TFNB) was chosen as an antenna to synthesize ternary complexes. The addition of DPA on EuGNP:TFNB ternary complex quenched the initial emission of the complex at 615 nm and increased the TFNB emission at 450 nm when excited at 350 nm. The results demonstrated that the ratiometric fluorescent detection of DPA was achieved by ligand displacement strategy.

  13. Production of a soluble recombinant prion protein fused to blue fluorescent protein without refolding or detergents in Escherichia coli cells.

    Science.gov (United States)

    Arii, Yasuhiro; Yamaguchi, Hidenori; Fukuoka, Shin-Ichi

    2007-10-01

    The physiological function of prion proteins (PrP) remains unclear. To investigate the physiological relevance of PrP, we constructed a fusion protein of PrP with enhanced blue fluorescent protein (PrP-EBFP) to quantify the interaction of PrP with other molecules. Production of soluble PrP-EBFP was achieved by lowering the expression temperature in Escherichia coli (E. coli) cells to 15 degrees C. Soluble PrP-EBFP was purified on cation exchange and heparin-affinity columns to yield high purity protein. This is the first report of the preparation of soluble recombinant PrP without refolding following solubilization using denaturants or disruption using detergents. To confirm the integrity of PrP-EBFP, anisotropy was estimated under physiological conditions in the presence of heparin, which interacts with PrP. The dissociation constant was determined to be 0.88+/-0.07 microM. PrP-EBFP should be useful in the quantification of PrP interactions with other molecules.

  14. Label-Free Detection of Bacillus anthracis Spore Uptake in Macrophage Cells Using Analytical Optical Force Measurements.

    Science.gov (United States)

    Hebert, Colin G; Hart, Sean; Leski, Tomasz A; Terray, Alex; Lu, Qin

    2017-10-03

    Understanding the interaction between macrophage cells and Bacillus anthracis spores is of significant importance with respect to both anthrax disease progression, spore detection for biodefense, as well as understanding cell clearance in general. While most detection systems rely on specific molecules, such as nucleic acids or proteins and fluorescent labels to identify the target(s) of interest, label-free methods probe changes in intrinsic properties, such as size, refractive index, and morphology, for correlation with a particular biological event. Optical chromatography is a label free technique that uses the balance between optical and fluidic drag forces within a microfluidic channel to determine the optical force on cells or particles. Here we show an increase in the optical force experienced by RAW264.7 macrophage cells upon the uptake of both microparticles and B. anthracis Sterne 34F2 spores. In the case of spores, the exposure was detected in as little as 1 h without the use of antibodies or fluorescent labels of any kind. An increase in the optical force was also seen in macrophage cells treated with cytochalasin D, both with and without a subsequent exposure to spores, indicating that a portion of the increase in the optical force arises independent of phagocytosis. These results demonstrate the capability of optical chromatography to detect subtle biological differences in a rapid and sensitive manner and suggest future potential in a range of applications, including the detection of biological threat agents for biodefense and pathogens for the prevention of sepsis and other diseases.

  15. The role of water radicals in thermorestoration of bacterial spores

    International Nuclear Information System (INIS)

    Friedman, Y.S.; Grecz, N.

    1974-01-01

    Fully hydrated bacterial spores exposed to 0.45 Mrad showed a characteristic pattern of survival associated with thermorestoration. When temperature during radiation was controlled at -15 0 to +120 0 C, the lowest viable cell counts were at 0 0 C. Above 0 0 C radiosurvival gradually increased by 2 to 3 log cycles reaching peak at 75 0 C (Bacillus cereus T heat sensitive spores) and at 95 0 C (B.stearothermophilus, heat resistant spores). Simultaneously high survival was observed in the solidly frozen state at -15 0 C to -5 0 C since harmful radicals produced by radiation were trapped in ice. Radiation modifying effects, i.e., protection by 2M ethanol (a scavenger of OH radicals) and sensitization by 1M sodium nitrate (a scavenger of H radicals and hydrated electrons), were studied. The results with ethanol and nitrate confirm the idea that in aqueous sytems below 50 0 C the lethal action is due to oxidizing OH radicals known to attack cell DNA. However, the reversal of scavenger actions above 50 0 C indicates that at those high temperatures lethal effects may also involve the reducing H and esub(aq), which at lower temperatures appear not to affect spore survival though they are known to attack proteins. In this case, it is proposed that radiation inactivation of spores at temperatures below 50 0 C is due to DNA damage inflicted by OH radicals whereas spore death above 50 0 C seems to involve protein /enzyme/ inactivation due to a combined action of heat plus reducing (H, esub(aq)) as well as oxidizing (OH) radical species. From the practical point of view it is important that normally radioprotective effects of such substances as ethanol or ground beef are progressively lost when radiation is carried out at temperatures above 50 0 C. (F.J.)

  16. Evidence for the monomerization of spore photoproduct to two thymines by the light-independent 'spore repair' process in Bacillus subtilis

    International Nuclear Information System (INIS)

    Van Wang, T.-C.; Rupert, C.S.

    1977-01-01

    Ultraviolet irradiation of bacterial spores induces a unique DNA photoproduct, which yields mostly 5-thyminyl-5,6-dihydrothymine (Thy(α-5)hThy, or TDHT) on acid hydrolysis. One of the possible mechanisms for the observed removal of the photoproduct on spore germination ivolves its direct conversion back to two adjacent thymine residues, and additional evidence is presented in support of this theory. Studies were made of the fate of the TDHT radioactivity in irradiated, germinated B. subtilis spores labelled with 3 H-thymine or 14 C-thymine, and of the homogeneity of the thymine-peak radioactivity. The radioactivity disappearing from the TDHT peak on germination seemed to be stoichiometrically recovered in the thymine peak, and no new materials were detected under the thymine-peak radioactivity. No intermediates were detected in B. subtilis mutant 25D4 (hcr 42 - recA 1 - ), a strain which had given some promise of accumulating intermediates from an incomplete repair process. (U.K.)

  17. Soluble Protein Analysis using a Compact Bench-top Flow Cytometer

    Science.gov (United States)

    Pappas, Dimitri; Kao, Shib-Hsin; Cyr, Johnathan

    2004-01-01

    Future space exploration missions will require analytical technology capable of providing both autonomous medical care to the crew and investigative capabilities to researchers. While several promising candidate technologies exist for further development, flow cytometry is an attractive technology as it offers both crew health (blood cell count, leukocyte differential, etc.) and a wide array of biochemistry and immunology assays. research settings, the application of this technique to soluble protein analysis is also possible. Proteomic beads using fluorescent dyes for optical encoding were used to monitor six cytokines simultaneously in cell medium of cell cultures in stationary and rotating cell culture systems. The results of this work demonstrate that a compact flow cytometer, such as a system proposed for space flight, can detect a variety of soluble proteins for crew health and biotechnology experiments during long-term missions.

  18. The Cooperative and Interdependent Roles of GerA, GerK, and Ynd in Germination of Bacillus licheniformis Spores.

    Science.gov (United States)

    Borch-Pedersen, Kristina; Lindbäck, Toril; Madslien, Elisabeth H; Kidd, Shani W; O'Sullivan, Kristin; Granum, Per Einar; Aspholm, Marina

    2016-07-15

    When nutrients are scarce, Bacillus species form metabolically dormant and extremely resistant spores that enable survival over long periods of time under conditions not permitting growth. The presence of specific nutrients triggers spore germination through interaction with germinant receptors located in the spore's inner membrane. Bacillus licheniformis is a biotechnologically important species, but it is also associated with food spoilage and food-borne disease. The B. licheniformis ATCC 14580/DSM13 genome exhibits three gerA family operons (gerA, gerK, and ynd) encoding germinant receptors. We show that spores of B. licheniformis germinate efficiently in response to a range of different single l-amino acid germinants, in addition to a weak germination response seen with d-glucose. Mutational analyses revealed that the GerA and Ynd germination receptors function cooperatively in triggering an efficient germination response with single l-amino acid germinants, whereas the GerK germination receptor is essential for germination with d-glucose. Mutant spores expressing only GerA and GerK or only Ynd and GerK show reduced or severely impaired germination responses, respectively, with single l-amino acid germinants. Neither GerA nor Ynd could function alone in stimulating spore germination. Together, these results functionally characterize the germination receptor operons present in B. licheniformis We demonstrate the overlapping germinant recognition patterns of the GerA and Ynd germination receptors and the cooperative functionalities between GerA, Ynd, and GerK in inducing germination. To ensure safe food production and durable foods, there is an obvious need for more knowledge on spore-forming bacteria. It is the process of spore germination that ultimately leads to food spoilage and food poisoning. Bacillus licheniformis is a biotechnologically important species that is also associated with food spoilage and food-borne disease. Despite its importance, the

  19. Effect of irradiation of bacteria on the formation of spores

    International Nuclear Information System (INIS)

    Szulc, M.; Tropilo, J.; Olszewski, G.

    1980-01-01

    Studies were carried out on bacteria: Bac. subtilis, Bac. cereus, Cl. perfringens, Cl. botulinum which were irradiated in two media (PBS and broth containing 1% of protein) with 100, 1000, 5000 and 10 000 X-radiation doses. The results obtained show that: all bacteria species studied (vegetative forms) are characterized by a high sensitivity to X-radiation, though distinctly lower than the species of Enterobacteriaceae family; the bacteria species studied are characterized by various sporing rate. The highest sporing rate was shown by Bac. cereus, the following: Bac. subtilis, Cl. perfringens and Cl. botulinum; increased X-radiation doses weaken sporing of Bac. subtilis and Bac. cereus. This effect could not be observed in Cl. perfringens and Cl. botulinum. (author)

  20. Effect of irradiation of bacteria on the formation of spores

    Energy Technology Data Exchange (ETDEWEB)

    Szulc, M.; Tropilo, J.; Olszewski, G.

    1980-01-01

    Studies were carried out on bacteria: Bac. subtilis, Bac. cereus, Cl. perfringens, Cl. botulinum which were irradiated in two media (PBS and broth containing 1% of protein) with 100, 1000, 5000 and 10 000 X-radiation doses. The results obtained show that: all bacteria species studied (vegetative forms) are characterized by a high sensitivity to X-radiation, though distinctly lower than the species of Enterobacteriaceae family; the bacteria species studied are characterized by various sporing rate. The highest sporing rate was shown by Bac. cereus, the following: Bac. subtilis, Cl. perfringens and Cl. botulinum; increased X-radiation doses weaken sporing of Bac. subtilis and Bac. cereus. This effect could not be observed in Cl. perfringens and Cl. botulinum.

  1. Inactivation of Bacillus subtilis spores by high pressure CO2 with high temperature.

    Science.gov (United States)

    Rao, Lei; Xu, Zhenzhen; Wang, Yongtao; Zhao, Feng; Hu, Xiaosong; Liao, Xiaojun

    2015-07-16

    The objective of this study was to investigate the inactivation of the Bacillus subtilis spores by high pressure CO2 combined with high temperature (HPCD+HT) and to analyze the clumping effect of the spores on their HPCD+HT resistance. The spores of B. subtilis were subjected to heat at 0.1 MPa and HPCD at 6.5-25 MPa, and 82 °C, 86 °C, and 91 °C for 0-120 min. The spores were effectively inactivated by HPCD+HT, but a protective effect on the spores was also found, which was closely correlated to the pressure, temperature and time. The spores treated by HPCD+HT at 6.5 and 10 MPa exhibited a two-stage inactivation curve of shoulder and log-linear regions whereas the spores at 15-25 MPa exhibited a three-stage inactivation curve of shoulder, log-linear and tailing regions, and these curves were well fitted to the Geeraerd model. Approximately 90% of pyridine-2,6-dicarboxylic acid (DPA) was released after HPCD+HT and the 90% DPA release time depend on the pressure and temperature. Moreover, the spore clumping in suspensions was examined by dynamic light scattering. The particle size of the spore suspensions increased with the increase of pressure, temperature and time, indicating the spore clumping. 0.1% Tween 80 as a surfactant inhibited the spore clumping and increased the inactivation ratio of the spores by HPCD+HT. These results indicated that the spore clumping enhanced the spores' resistance to HPCD+HT and induced a protective effect. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Efficient Enzymatic Synthesis of Phenolic Ester by Increasing Solubility of Phenolic Acids in Ionic Liquids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    Compounds from phenolic acid family are well known natural antioxidants, but the application of phenolic acids as antioxidants in industry is limited due to the relatively low solubility in oil-based media. The properties of phenolic acids can be modified through enzymatic lipophilization...... and modified phenolic acids will have amphiphilic property, therefore they can be localized at oil-water or water-oil phase where oxidation is considered to occur frequently. It had been reported that immobilized Candida Antarctica lipase B was the most effective biocatalyst for the various esterification...... reactions, and it had been widely used for esterification of various phenolic acids with fatty alcohol or triglycerides. However, the conversion of phenolic acids is low due to low solubility in hydrophobic solvents and hindrance effect of unsaturated side chain towards the enzyme. Our studies show...

  3. Effect of whey protein isolate films incorporated with montmorillonite and citric acid on the preservation of fresh-cut apples.

    Science.gov (United States)

    Azevedo, Viviane Machado; Dias, Marali Vilela; de Siqueira Elias, Heloisa Helena; Fukushima, Katia Lumi; Silva, Eric Keven; de Deus Souza Carneiro, João; de Fátima Ferreira Soares, Nilda; Borges, Soraia Vilela

    2018-05-01

    The objective of this paper was to evaluate the effect of bioactive whey protein isolate/montmorillonite films containing citric acid on the inhibition of enzymatic browning and physicochemical properties in minimally processed apples. Whey protein isolate films incorporated with montmorillonite (3 g/100 g) and citric acid (5 and 10 g/100 g) were applied to the apples slices. All samples were packaged in polypropylene trays (14.6 cm × 11.4 cm × 6.5 cm) and stored at 5 ± 2 °C and 85 ± 3% RH for eight days. Every two days, the apples samples were evaluated for color, acidity, pH, soluble solids, water activity and polyphenol oxidase and peroxidase enzyme activity. The enzymatic browning of the apples slices was reduced for all films during storage. However, the films containing citric acid maintained the color characteristics, reducing the loss of quality associated the maintenance of acidity, soluble solids, water activity, reduction of polyphenol oxidase and peroxidase activity, thus prolonging the shelf life of the apples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Use of Fatty Acid Methyl Ester Profiles for Discrimination of Bacillus cereus T-Strain Spores Grown on Different Media▿

    OpenAIRE

    Ehrhardt, Christopher J.; Chu, Vivian; Brown, TeeCie; Simmons, Terrie L.; Swan, Brandon K.; Bannan, Jason; Robertson, James M.

    2010-01-01

    The goal of this study was to determine if cellular fatty acid methyl ester (FAME) profiling could be used to distinguish among spore samples from a single species (Bacillus cereus T strain) that were prepared on 10 different medium formulations. To analyze profile differences and identify FAME biomarkers diagnostic for the chemical constituents in each sporulation medium, a variety of statistical techniques were used, including nonmetric multidimensional scaling (nMDS), analysis of similarit...

  5. Semen quality and concentration of soluble proteins in the seminal plasma of Alpine bucks Semen quality and concentration of soluble proteins in the seminal plasma of Alpine bucks

    Directory of Open Access Journals (Sweden)

    Simone Eliza Facione Guimarães

    2010-06-01

    Full Text Available It was aimed to study the in vitro seminal quality analyzed by complementary tests and to compare them with physical, morphological and biochemical aspects of male goat semen of the Alpine breed. This experiment took place at the Federal University of Viçosa, situated at 20º45’ S latitude and 42º51’ W longitude, Southwest of Brazil. It was done during the summer months of January and February, and three adult male goats of the Alpine breed were used in intensive conditions. The semen was collected by artificial vagina method. In all semen samples (45 ejaculates, after the physical and morphological analysis, the hiposmotic test was done. In 24 ejaculates, it were done thermo-resistance test, and in 21 ejaculates it were determined the concentration of total soluble proteins in seminal plasma. The male goats presented difference in the semen physical and morphological aspects, in the hiposmotic test and thermo-resistance test, but they did not presented difference in total soluble proteins concentration in seminal plasma. Results of the slow thermo-resistance test and hiposmotic test were positively correlated (r = 0.60. It was concluded, according to our results, that the concentration of total soluble proteins in seminal plasma can not be used as a parameter to predict the seminal quality of Alpine bucks.It was aimed to study the in vitro seminal quality analyzed by complementary tests and to compare them with physical, morphological and biochemical aspects of male goat semen of the Alpine breed. This experiment took place at the Federal University of Viçosa, situated at 20º45’ S latitude and 42º51’ W longitude, Southwest of Brazil. It was done during the summer months of January and February, and three adult male goats of the Alpine breed were used in intensive conditions. The semen was collected by artificial vagina method. In all semen samples (45 ejaculates, after the physical and morphological analysis, the hiposmotic test

  6. Salt-soluble proteins from wheat-derived foodstuffs show lower allergenic potency than those from raw flour.

    Science.gov (United States)

    de Gregorio, Marta; Armentia, Alicia; Díaz-Perales, Araceli; Palacín, Arantxa; Dueñas-Laita, Antonio; Martín, Blanca; Salcedo, Gabriel; Sánchez-Monge, Rosa

    2009-04-22

    Salt-soluble proteins from wheat flour have been described as main allergens associated with both baker's asthma and food allergy. However, most studies have used raw flour as starting material, thus not considering potential changes in allergenic properties induced by the heat treatment and other industrial processing to produce wheat-derived foodstuffs. Salt extracts from different commercial wheat-derived products were obtained and their allergenic properties investigated by IgE-immunodetection, ELISA assays, and skin prick test. The IgE-binding capacity of salt-soluble proteins from commercial breads and cooked pastas was reduced around 50% compared with that of raw flour, the reduction being less dramatic in noncooked pastas and biscuits. Several wheat-derived foodstuffs showed major IgE-binding components of 20 and 35 kDa, identified as avenin-like and globulin proteins, respectively. These proteins, as well as most flour and bread salt-soluble proteins, were hydrolyzed when subjected to simulated gastrointestinal digestion. However, the digested products still exhibited a residual IgE-binding capacity. Therefore, processing of wheat flour to obtain derived foodstuffs decreases the IgE binding-capacity of the major salt-soluble wheat proteins. Moreover, simulated gastric fluid digestion further inactivates some heat-resistant IgE-binding proteins.

  7. On solubility of perchloric (periodic) acid and α-cyanacetanmide in aqueous solutions at 25 deg C

    International Nuclear Information System (INIS)

    Omarova, R.A.; Balysbekov, S.M.; Erkasov, R.Sh.; Nikolenko, O.N.

    1996-01-01

    Acid-base interaction within perchloric (periodic) acid-α-cyanacetamide-water systems in studied by method of solubility under isothermal conditions at 25 deg C. Solubility regularities of crystalline α-cyanacetamide in perchloric and periodic acid solutions are determined, the concentration limits of formation of a new solid phase-tris(α-cyanacetamide) perchlorate within perchloric acid-α-cyanacetamide-water system are determined. The compound is identified by means of chemical and X-ray phase analyses, its density and melting temperature are determined. Iodic acid and α-cyanacetamide water solution base system is shown to belong to a simple eutonic type. 2 refs., 3 figs., 2 tabs

  8. THE EFFECT OF THE PROTEIN SOLUBILITY OF FISH MEAL AND ...

    African Journals Online (AJOL)

    utilization of fish meal proteins was determined by a relationship between their solubility or apparent digestibility and the ... Data obtained from these trials should indicate what re- ..... 4 in mind it is thus obvious that the big variation which oc-.

  9. Effects of microbial loading and sporulation temperature on atmospheric plasma inactivation of Bacillus subtilis spores

    Science.gov (United States)

    Deng, X. T.; Shi, J. J.; Shama, G.; Kong, M. G.

    2005-10-01

    Current inactivation studies of Bacillus subtilis spores using atmospheric-pressure glow discharges (APGD) do not consider two important factors, namely microbial loading at the surface of a substrate and sporulation temperature. Yet these are known to affect significantly microbial resistance to heat and hydrogen peroxide. This letter investigates effects of microbial loading and sporulation temperature on spore resistance to APGD. It is shown that microbial loading can lead to a stacking structure as a protective shield against APGD treatment and that high sporulation temperature increases spore resistance by altering core water content and cross-linked muramic acid content of B. subtilis spores.

  10. Heat and UV light resistance of vegetative cells and spores of Bacillus subtilis rec-mutants

    International Nuclear Information System (INIS)

    Hanlin, J.H.; Lombardi, S.J.; Slepecky, R.A.

    1985-01-01

    The heat and UV light resistance of spores and vegetative cells of Bacillus subtilis BD170 (rec+) were greater than those of B. subtilis BD224 (recE4). Strain BD170 can repair DNA whereas BD224 is repair deficient due to the presence of the recE4 allele. Spores of a GSY Rec+ strain were more heat resistant than spores of GSY Rec- and Uvr- mutants. The overall level of heat and UV light resistance attained by spores may in part be determined by their ability to repair deoxyribonucleic acid after exposure to these two physical mutagens

  11. Rapid Detection of Bacillus anthracis Spores Using Immunomagnetic Separation and Amperometry

    Directory of Open Access Journals (Sweden)

    David F. Waller

    2016-12-01

    Full Text Available Portable detection and quantitation methods for Bacillus anthracis (anthrax spores in pure culture or in environmental samples are lacking. Here, an amperometric immunoassay has been developed utilizing immunomagnetic separation to capture the spores and remove potential interferents from test samples followed by amperometric measurement on a field-portable instrument. Antibody-conjugated magnetic beads and antibody-conjugated glucose oxidase were used in a sandwich format for the capture and detection of target spores. Glucose oxidase activity of spore pellets was measured indirectly via amperometry by applying a bias voltage after incubation with glucose, horseradish peroxidase, and the electron mediator 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid. Target capture was mediated by polyclonal antisera, whereas monoclonal antibodies were used for signal generation. This strategy maximized sensitivity (500 target spores, 5000 cfu/mL, while also providing a good specificity for Bacillus anthracis spores. Minimal signal deviation occurs in the presence of environmental interferents including soil and modified pH conditions, demonstrating the strengths of immunomagnetic separation. The simultaneous incubation of capture and detection antibodies and rapid substrate development (5 min result in short sample-to-signal times (less than an hour. With attributes comparable or exceeding that of ELISA and LFDs, amperometry is a low-cost, low-weight, and practical method for detecting anthrax spores in the field.

  12. Activation of human natural killer cells by the soluble form of cellular prion protein

    International Nuclear Information System (INIS)

    Seong, Yeon-Jae; Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon; Park, Bum-Chan; Park, Su-Hyung; Park, Young Woo; Shin, Eui-Cheol

    2015-01-01

    Cellular prion protein (PrP C ) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP C in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP C protein on human natural killer (NK) cells. Recombinant soluble PrP C protein was generated by fusion of human PrP C with the Fc portion of human IgG 1 (PrP C -Fc). PrP C -Fc binds to the surface of human NK cells, particularly to CD56 dim NK cells. PrP C -Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP C -Fc facilitated the IL-15-induced proliferation of NK cells. PrP C -Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP C -Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP C (PrP C -Fc) was generated by fusion of human PrP C with IgG1 Fc portion. • PrP C -Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP C -Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways

  13. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Energy Technology Data Exchange (ETDEWEB)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  14. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    International Nuclear Information System (INIS)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad

    2015-01-01

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  15. Compartment-specific pH monitoring in Bacillus subtilis using fluorescent sensor proteins: a tool to analyze the antibacterial effect of weak organic acids.

    Science.gov (United States)

    van Beilen, Johan W A; Brul, Stanley

    2013-01-01

    The internal pH (pHi) of a living cell is one of its most important physiological parameters. To monitor the pH inside Bacillus subtilis during various stages of its life cycle, we constructed an improved version (IpHluorin) of the ratiometric, pH-sensitive fluorescent protein pHluorin by extending it at the 5' end with the first 24 bp of comGA. The new version, which showed an approximate 40% increase in fluorescence intensity, was expressed from developmental phase-specific, native promoters of B. subtilis that are specifically active during vegetative growth on glucose (PptsG) or during sporulation (PspoIIA, PspoIIID, and PsspE). Our results show strong, compartment-specific expression of IpHluorin that allowed accurate pHi measurements of live cultures during exponential growth, early and late sporulation, spore germination, and during subsequent spore outgrowth. Dormant spores were characterized by an pHi of 6.0 ± 0.3. Upon full germination the pHi rose dependent on the medium to 7.0-7.4. The presence of sorbic acid in the germination medium inhibited a rise in the intracellular pH of germinating spores and inhibited germination. Such effects were absent when acetic was added at identical concentrations.

  16. Compartment-specific pH monitoring in Bacillus subtilis using fluorescent sensor proteins; a tool to analyse the antibacterial effect of weak organic acids.

    Directory of Open Access Journals (Sweden)

    Johan W.A. van Beilen

    2013-06-01

    Full Text Available The internal pH (pHi of a living cell is one of its most important physiological parameters. To monitor the pH inside B. subtilis during various stages of its life cycle, we constructed an improved version (IpHluorin of the ratiometric, pH-sensitive fluorescent protein pHluorin by extending it at the 5’ end with the first 24 bp of comGA. The new version, which showed an approximate 40% increase in fluorescence intensity, was expressed from developmental phase-specific, native promoters of B. subtilis that are specifically active during vegetative growth on glucose (PptsG or during sporulation (PspoIIA, PspoIIID and PsspE. Our results show strong, compartment-specific expression of IpHluorin that allowed accurate pHi measurements of live cultures during exponential growth, early and late sporulation, spore germination, and during subsequent spore outgrowth. Dormant spores were characterised by an internal pH of 6.0 ± 0.3. Upon full germination the internal pH rose dependent on the medium to 7.0-7.4. The presence of sorbic acid in the germination medium inhibited a rise in the intracellular pH of germinating spores and inhibited germination. Such effects were absent when acetic was added at identical concentrations.

  17. Contamination pathways of spore-forming bacteria in a vegetable cannery.

    Science.gov (United States)

    Durand, Loïc; Planchon, Stella; Guinebretiere, Marie-Hélène; André, Stéphane; Carlin, Frédéric; Remize, Fabienne

    2015-06-02

    Spoilage of low-acid canned food during prolonged storage at high temperatures is caused by heat resistant thermophilic spores of strict or facultative bacteria. Here, we performed a bacterial survey over two consecutive years on the processing line of a French company manufacturing canned mixed green peas and carrots. In total, 341 samples were collected, including raw vegetables, green peas and carrots at different steps of processing, cover brine, and process environment samples. Thermophilic and highly-heat-resistant thermophilic spores growing anaerobically were counted. During vegetable preparation, anaerobic spore counts were significantly decreased, and tended to remain unchanged further downstream in the process. Large variation of spore levels in products immediately before the sterilization process could be explained by occasionally high spore levels on surfaces and in debris of vegetable combined with long residence times in conditions suitable for growth and sporulation. Vegetable processing was also associated with an increase in the prevalence of highly-heat-resistant species, probably due to cross-contamination of peas via blanching water. Geobacillus stearothermophilus M13-PCR genotypic profiling on 112 isolates determined 23 profile-types and confirmed process-driven cross-contamination. Taken together, these findings clarify the scheme of contamination pathway by thermophilic spore-forming bacteria in a vegetable cannery. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Applications of hydrophilic interaction chromatography to amino acids, peptides, and proteins.

    Science.gov (United States)

    Periat, Aurélie; Krull, Ira S; Guillarme, Davy

    2015-02-01

    This review summarizes the recent advances in the analysis of amino acids, peptides, and proteins using hydrophilic interaction chromatography. Various reports demonstrate the successful analysis of amino acids under such conditions. However, a baseline resolution of the 20 natural amino acids has not yet been published and for this reason, there is often a need to use mass spectrometry for detection to further improve selectivity. Hydrophilic interaction chromatography is also recognized as a powerful technique for peptide analysis, and there are a lot of papers showing its applicability for proteomic applications (peptide mapping). It is expected that its use for peptide mapping will continue to grow in the future, particularly because this analytical strategy can be combined with reversed-phase liquid chromatography, in a two-dimensional setup, to reach very high resolving power. Finally, the interest in hydrophilic interaction chromatography for intact proteins analysis is less evident due to possible solubility issues and a lack of suitable hydrophilic interaction chromatography stationary phases. To date, it has been successfully employed only for the characterization of membrane proteins, histones, and the separation of glycosylated isoforms of an intact glycoprotein. From our point of view, the number of hydrophilic interaction chromatography columns compatible with intact proteins (higher upper temperature limit, large pore size, etc.) is still too limited. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The resistance of Bacillus atrophaeus spores to the bactericidal activity of peracetic acid is influenced by both the nature of the solid substrates and the mode of contamination.

    Science.gov (United States)

    Grand, I; Bellon-Fontaine, M-N; Herry, J-M; Hilaire, D; Moriconi, F-X; Naïtali, M

    2010-11-01

    To evaluate the impact of the mode of contamination in relation with the nature of solid substrates on the resistance of spores of Bacillus atrophaeus -selected as surrogates of Bacillus anthracis- to a disinfectant, peracetic acid. Six materials confronted in urban and military environments were selected for their different structural and physicochemical properties. In parallel, two modes of contamination were examined, i.e. deposition and immersion. Deposition was used to simulate contamination by an aerosol and immersion by an extended contact with liquids. A pronounced difference in the biocontamination levels and spatial organization of spores was observed depending on the mode of contamination and the nature of the solid substrate considered, with consequences on decontamination. Contamination by immersion led to lower efficiency of peracetic acid decontamination than contamination by deposition. Infiltration of spores into porous materials after immersion is one reason. In contrast, the deposition mode aggregates cells at the surface of materials, explaining the similar disinfecting behaviour of porous and nonporous substrates when considering this inoculation route. The inoculation route was shown to be as influential a parameter as material characteristics (porosity and wettability) for decontamination efficacy. These results provide comparative information for the decontamination of B. atrophaeus spores in function of the mode of contamination and the nature of solid substrates. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology. No claim to French government works.

  20. Solubility Testing of Sucrose Esters of Fatty Acids in International Food Additive Specifications.

    Science.gov (United States)

    Nagai, Yukino; Kawano, Satoko; Motoda, Kenichiro; Tomida, Masaaki; Tatebe, Chiye; Sato, Kyoko; Akiyama, Hiroshi

    2017-03-01

    We investigated the solubility of 10 samples of sucrose esters of fatty acids (SEFA) products that are commercially available worldwide as food additives (emulsifiers). Although one sample dissolved transparently in both water and ethanol, other samples produced white turbidity and/or precipitates and did not meet the solubility criterion established by the Joint Food and Agriculture Organization of the United Nations (FAO)/WHO Expert Committee on Food Additives (JECFA). When the sample solutions were heated, the solubility in both water and ethanol increased. All of the samples dissolved transparently in ethanol, and dispersed and became white without producing precipitates in water. The present study suggests that the current solubility criterion of the JECFA SEFA specifications needs to be revised.

  1. Efficient Route to Highly Water-Soluble Aromatic Cyclic Hydroxamic Acid Ligands

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Michael; Raymond, Kenneth N.

    2008-02-06

    2-Hydroxyisoquinolin-1-one (1,2-HOIQO) is a new member of the important class of aromatic cyclic hydroxamic acid ligands which are widely used in metal sequestering applications and metal chelating therapy. The first general approach for the introduction of substituents at the aromatic ring of the chelating moiety is presented. As a useful derivative, the highly water-soluble sulfonic acid has been synthesized by an efficient route that allows general access to 1,2-HOQIO 3-carboxlic acid amides, which are the most relevant for applications.

  2. Effect of Ultrasonic Waves on the Heat Resistance of Bacillus cereus and Bacillus licheniformis Spores

    Science.gov (United States)

    Burgos, J.; Ordóñez, J. A.; Sala, F.

    1972-01-01

    Heat resistance of Bacillus cereus and Bacillus licheniformis spores in quarter-strength Ringer solution decreases markedly after ultrasonic treatments which are unable to kill a significant proportion of the spore population. This effect does not seem to be caused by a loss of Ca2+ or dipicolinic acid. The use of ultrasonics to eliminate vegetative cells or to break aggregates in Bacillus spore suspensions to be used subsequently in heat resistance experiments appears to be unadvisable. PMID:4627969

  3. Solubility of 3-Caffeoylquinic Acid in Different Solvents at 291-340 K

    Science.gov (United States)

    Wang, Y. T.; Zhang, C. L.; Cheng, X. L.; Zhao, J. H.; Wang, L. C.

    2017-12-01

    Using a laser monitoring observation technique the solubilities of 3-caffeoylquinic acid in pure solvents, water, methanol, ethanol, 1-propanol, 1-butanol, and two mixed solvents, methanol + water, ethanol + water have been determined at temperature range from 291-340 K. The experimental data were correlated by the modified Apelblat equation, λ h equation, and ideal model. The calculated solubilities were turned out very consistent with the experimental results, and the modified Apelblat equation shows the best agreement.

  4. Amino acids and proteins

    NARCIS (Netherlands)

    van Goudoever, Johannes B.; Vlaardingerbroek, Hester; van den Akker, Chris H.; de Groof, Femke; van der Schoor, Sophie R. D.

    2014-01-01

    Amino acids and protein are key factors for growth. The neonatal period requires the highest intake in life to meet the demands. Those demands include amino acids for growth, but proteins and amino acids also function as signalling molecules and function as neurotransmitters. Often the nutritional

  5. Neptunium (IV) oxalate solubility

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1983-07-01

    The equilibrium solubility of neptunium (IV) oxalate in nitric/oxalic acid solutions was determined at 22 0 C, 45 0 C, and 60 0 C. The concentrations of nitric/oxalic acid solutions represented a wide range of free oxalate ion concentration. A mathematical solubility model was developed which is based on the formation of the known complexes of neptunium (IV) oxalate. the solubility model uses a simplified concentration parameter which is proportional to the free oxalate ion concentration. The solubility model can be used to estimate the equilibrium solubility of neptunium (IV) oxalate over a wide range of oxalic and nitric acid concentrations at each temperature

  6. Investigation on the turnover of plant proteins. 2

    International Nuclear Information System (INIS)

    Becker, R.; Winkler, E.; Jung, K.; Huebner, G.

    1981-01-01

    Based on kinetic analyses of amino acid and protein turnover by means of compartment models the synthesis and degradation of the soluble proteins in etiolated epicotyl segments of Pisum sativum L. as well as their dependence on the herbicide 2'-methyl-4'-chlorophenoxyacetic acid (MCPA) were determined quantitatively. The segments were incubated for 10 h in a medium containing 14 C-leucine and subsequently placed in an inactive medium. The radioactivity in the soluble proteins and in the amino acid fraction was followed up for a total of 24 h. A 3-pool model in which the total measurable amino acid pool was divided into a direct precursor pool for protein synthesis and into a degradation pool was best suited to interpret the data. The turnover rate for the soluble proteins of untreated epicotyl segments was determined to be 0.058 h -1 ; at an MCPA concentration of 10 -4 M this value was nearly doubled. An increased proteolytic activity in the epicotyl segments ran parallel to the change of the turnover rate in dependence on MCPA concentration. The heterogeneity of the soluble protein with respect to the turnover rate was investigated by means of 3 H/ 14 C double labelling for individual protein fractions separated by gel electrophoresis. The results obtained in this way were comparable with those of the total pool turnover. (author)

  7. A family of E. coli expression vectors for laboratory scale and high throughput soluble protein production

    Directory of Open Access Journals (Sweden)

    Bottomley Stephen P

    2006-03-01

    Full Text Available Abstract Background In the past few years, both automated and manual high-throughput protein expression and purification has become an accessible means to rapidly screen and produce soluble proteins for structural and functional studies. However, many of the commercial vectors encoding different solubility tags require different cloning and purification steps for each vector, considerably slowing down expression screening. We have developed a set of E. coli expression vectors with different solubility tags that allow for parallel cloning from a single PCR product and can be purified using the same protocol. Results The set of E. coli expression vectors, encode for either a hexa-histidine tag or the three most commonly used solubility tags (GST, MBP, NusA and all with an N-terminal hexa-histidine sequence. The result is two-fold: the His-tag facilitates purification by immobilised metal affinity chromatography, whilst the fusion domains act primarily as solubility aids during expression, in addition to providing an optional purification step. We have also incorporated a TEV recognition sequence following the solubility tag domain, which allows for highly specific cleavage (using TEV protease of the fusion protein to yield native protein. These vectors are also designed for ligation-independent cloning and they possess a high-level expressing T7 promoter, which is suitable for auto-induction. To validate our vector system, we have cloned four different genes and also one gene into all four vectors and used small-scale expression and purification techniques. We demonstrate that the vectors are capable of high levels of expression and that efficient screening of new proteins can be readily achieved at the laboratory level. Conclusion The result is a set of four rationally designed vectors, which can be used for streamlined cloning, expression and purification of target proteins in the laboratory and have the potential for being adaptable to a high

  8. Activation of human natural killer cells by the soluble form of cellular prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Yeon-Jae [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Hafis Clinic, Seoul (Korea, Republic of); Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Bum-Chan [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Park, Su-Hyung [Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Shin, Eui-Cheol, E-mail: ecshin@kaist.ac.kr [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-08-21

    Cellular prion protein (PrP{sup C}) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP{sup C} in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP{sup C} protein on human natural killer (NK) cells. Recombinant soluble PrP{sup C} protein was generated by fusion of human PrP{sup C} with the Fc portion of human IgG{sub 1} (PrP{sup C}-Fc). PrP{sup C}-Fc binds to the surface of human NK cells, particularly to CD56{sup dim} NK cells. PrP{sup C}-Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP{sup C}-Fc facilitated the IL-15-induced proliferation of NK cells. PrP{sup C}-Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP{sup C}-Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP{sup C} (PrP{sup C}-Fc) was generated by fusion of human PrP{sup C} with IgG1 Fc portion. • PrP{sup C}-Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP{sup C}-Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways.

  9. Soluble cysteine-rich tick saliva proteins Salp15 and Iric-1 from E. coli.

    Science.gov (United States)

    Kolb, Philipp; Vorreiter, Jolanta; Habicht, Jüri; Bentrop, Detlef; Wallich, Reinhard; Nassal, Michael

    2015-01-01

    Ticks transmit numerous pathogens, including borreliae, which cause Lyme disease. Tick saliva contains a complex mix of anti-host defense factors, including the immunosuppressive cysteine-rich secretory glycoprotein Salp15 from Ixodes scapularis ticks and orthologs like Iric-1 from Ixodes ricinus. All tick-borne microbes benefit from the immunosuppression at the tick bite site; in addition, borreliae exploit the binding of Salp15 to their outer surface protein C (OspC) for enhanced transmission. Hence, Salp15 proteins are attractive targets for anti-tick vaccines that also target borreliae. However, recombinant Salp proteins are not accessible in sufficient quantity for either vaccine manufacturing or for structural characterization. As an alternative to low-yield eukaryotic systems, we investigated cytoplasmic expression in Escherichia coli, even though this would not result in glycosylation. His-tagged Salp15 was efficiently expressed but insoluble. Among the various solubility-enhancing protein tags tested, DsbA was superior, yielding milligram amounts of soluble, monomeric Salp15 and Iric-1 fusions. Easily accessible mutants enabled epitope mapping of two monoclonal antibodies that, importantly, cross-react with glycosylated Salp15, and revealed interaction sites with OspC. Free Salp15 and Iric-1 from protease-cleavable fusions, despite limited solubility, allowed the recording of (1)H-(15)N 2D NMR spectra, suggesting partial folding of the wild-type proteins but not of Cys-free variants. Fusion to the NMR-compatible GB1 domain sufficiently enhanced solubility to reveal first secondary structure elements in (13)C/(15)N double-labeled Iric-1. Together, E. coli expression of appropriately fused Salp15 proteins may be highly valuable for the molecular characterization of the function and eventually the 3D structure of these medically relevant tick proteins.

  10. The search and identification of the new immunodiagnostic targets of bacillus anthracis spore

    International Nuclear Information System (INIS)

    Biketov, S.; Dunaytsev, I.; Baranova, E.; Marinin, L.; Dyatlov, I.

    2009-01-01

    Spores of Bacillus anthracis have been used as bio warfare agent to bio terrorize purposes. As efficiency of anti-epidemic measures included urgent prevention and treatment is determined by terms within which the bio agent is identified. Direct and rapid spore detection by antibodies based detection system is very attractive alternative to current PCR-based assays or routine phenotyping which are the most accurate but are also complex, time-consumption and expensive. The main difficulty with respect to such kind of anthrax spores detection is a cross-reaction with spores of closely related bacteria. For development of species-specific antibodies to anthrax spores recombinant scFvs or hybridoma technique were used. In both case surface spore antigens contained species-specific epitopes are need. Among exosporium proteins only ExsF(BxpB), ExsK and SoaA are specific to B.cereus group. On the surface of B. anthracis spores, a unique tetrasaccharides containing an novel monosaccharide - anthrose, was discovered. It was shown that anthrose can be serving as species-specific target for B. anthracis spores detection. We have revealed that EA1 isolated from spore of Russians strain STI-1 contain carbohydrate which formed species-specific epitopes and determine immunogenicity of this antigen. Antibodies to this antigen specifically recognized the surface target of B. anthracis spores and do not reacted with others Bacillus spore. Based on these antibodies we developed the test-systems in different formats for rapid direct detection and identification of B. anthracis spores. The results of trial these test-systems with using more than 50 different Bacillus strains were indicated that carbohydrate of EA1 isolated from spore is effective immunodiagnostic target for anthrax spores bio detection.(author)

  11. High Pressure Germination of Bacillus subtilis Spores with Alterations in Levels and Types of Germination Proteins

    Science.gov (United States)

    2014-01-01

    1ITLE AND SUBTITLE 5a CONTRACTNUMBER High pressure germination of Bacillus subtilis spores with W911NF-09-l-0286 alterations in levels and types of...A moderate high pressure (mHP) of 150 megaPascals (MPa) triggers germination of Bacillus subtilis spores via germinant receptors (GRs), while...germination by a very high pressure (vHP) of550 MPa is GR-independent. The mHP and vHP germination of Bacillus subtilis spores with different levels ofGRs

  12. Effects of High Pressure on Bacillus licheniformis Spore Germination and Inactivation.

    Science.gov (United States)

    Borch-Pedersen, Kristina; Mellegård, Hilde; Reineke, Kai; Boysen, Preben; Sevenich, Robert; Lindbäck, Toril; Aspholm, Marina

    2017-07-15

    Bacillus and Clostridium species form spores, which pose a challenge to the food industry due to their ubiquitous nature and extreme resistance. Pressurization at 300 MPa likely triggers germination by opening dipicolinic acid (DPA) channels present in the inner membrane of the spores. In this work, we expose spores of Bacillus licheniformis , a species associated with food spoilage and occasionally with food poisoning, to high pressure (HP) for holding times of up to 2 h. By using mutant spores lacking one or several GRs, we dissect the roles of the GerA, Ynd, and GerK GRs in moderately HP (mHP; 150 MPa)-induced spore germination. We show that Ynd alone is sufficient for efficient mHP-induced spore germination. GerK also triggers germination with mHP, although at a reduced germination rate compared to that of Ynd. GerA stimulates mHP-induced germination but only in the presence of either the intact GerK or Ynd GR. These results suggests that the effectiveness of the individual GRs in mHP-induced germination differs from their effectiveness in nutrient-induced germination, where GerA plays an essential role. In contrast to Bacillus subtilis spores, treatment with very HP (vHP) of 550 MPa at 37°C did not promote effective germination of B. licheniformis spores. However, treatment with vHP in combination with elevated temperatures (60°C) gave a synergistic effect on spore germination and inactivation. Together, these results provide novel insights into how HP affects B. licheniformis spore germination and inactivation and the role of individual GRs in this process. IMPORTANCE Bacterial spores are inherently resistant to food-processing regimes, such as high-temperature short-time pasteurization, and may therefore compromise food durability and safety. The induction of spore germination facilitates subsequent inactivation by gentler processing conditions that maintain the sensory and nutritional qualities of the food. High-pressure (HP) processing is a nonthermal

  13. Identification of a polymorphic collagen-like protein in the crustacean bacteria Pasteuria ramosa.

    Science.gov (United States)

    Mouton, Laurence; Traunecker, Emmanuel; McElroy, Kerensa; Du Pasquier, Louis; Ebert, Dieter

    2009-12-01

    Pasteuria ramosa is a spore-forming bacterium that infects Daphnia species. Previous results demonstrated a high specificity of host clone/parasite genotype interactions. Surface proteins of bacteria often play an important role in attachment to host cells prior to infection. We analyzed surface proteins of P. ramosa spores by two-dimensional gel electrophoresis. For the first time, we prove that two isolates selected for their differences in infectivity reveal few but clear-cut differences in protein patterns. Using internal sequencing and LC/MS/MS, we identified a collagen-like protein named Pcl1a (Pasteuria collagen-like protein 1a). This protein, reconstructed with the help of Pasteuria genome sequences, contains three domains: a 75-amino-acid amino-terminal domain with a potential transmembrane helix domain, a central collagen-like region (CLR) containing Gly-Xaa-Yaa (GXY) repeats, and a 7-amino-acid carboxy-terminal domain. The CLR region is polymorphic among the two isolates with amino-acid substitutions and a variable number of GXY triplets. Collagen-like proteins are rare in prokaryotes, although they have been described in several pathogenic bacteria, including Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis, closely related to Pasteuria species, in which they could be involved in the adherence of bacteria to host cells.

  14. Bacillus subtilis spores as vaccine adjuvants: further insights into the mechanisms of action.

    Directory of Open Access Journals (Sweden)

    Renata Damásio de Souza

    Full Text Available Bacillus subtilis spores have received growing attention regarding potential biotechnological applications, including the use as probiotics and in vaccine formulations. B. subtilis spores have also been shown to behave as particulate vaccine adjuvants, promoting the increase of antibody responses after co-administration with antigens either admixed or adsorbed on the spore surface. In this study, we further evaluated the immune modulatory properties of B. subtilis spores using a recombinant HIV gag p24 protein as a model antigen. The adjuvant effects of B. subtilis spores were not affected by the genetic background of the mouse lineage and did not induce significant inflammatory or deleterious effects after parenteral administration. Our results demonstrated that co-administration, but not adsorption to the spore surface, enhanced the immunogenicity of that target antigen after subcutaneous administration to BALB/c and C57BL/6 mice. Spores promoted activation of antigen presenting cells as demonstrated by the upregulation of MHC and CD40 molecules and enhanced secretion of pro-inflammatory cytokines by murine dendritic cells. In addition, in vivo studies indicated a direct role of the innate immunity on the immunomodulatory properties of B. subtilis spores, as demonstrated by the lack of adjuvant effects on MyD88 and TLR2 knockout mouse strains.

  15. Feasibility of flotation concentration of fungal spores as a method to identify toxigenic mushrooms

    Directory of Open Access Journals (Sweden)

    Bazzle LJ

    2014-12-01

    Full Text Available Lisa J Bazzle,1 Marc A Cubeta,2 Steven L Marks,1 David C Dorman3 1Department of Clinical Sciences, College of Veterinary Medicine, 2Department of Plant Pathology, College of Agriculture and Life Sciences, Center for Integrated Fungal Research, 3Department of Molecular and Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA Purpose: Mushroom poisoning is a recurring and challenging problem in veterinary medicine. Diagnosis of mushroom exposure in animals is hampered by the lack of rapid diagnostic tests. Our study evaluated the feasibility of using flotation concentration and microscopic evaluation of spores for mushroom identification. Evaluation of this method in living animals exposed to toxigenic mushrooms is limited by ethical constraints; therefore, we relied upon the use of an in vitro model that mimics the oral and gastric phases of digestion. Methods: In our study, mycologist-identified toxigenic (poisonous and nontoxigenic fresh mushrooms were collected in North Carolina, USA. In phase 1, quantitative spore recovery rates were determined following magnesium sulfate, modified Sheather's sugar solution, and zinc sulfate flotation (n=16 fungal species. In phase 2, mushrooms (n=40 fungal species were macerated and digested for up to 2 hours in a salivary and gastric juice simulant. The partially digested material was acid neutralized, filtered, and spores concentrated using zinc sulfate flotation followed by microscopic evaluation of spore morphology. Results: Mean spore recovery rates for the three flotation fluids ranged from 32.5% to 41.0% (P=0.82. Mean (± standard error of the mean Amanita spp. spore recovery rates were 38.1%±3.4%, 36.9%±8.6%, and 74.5%±1.6% (P=0.0012 for the magnesium sulfate, Sheather's sugar, and zinc sulfate solutions, respectively. Zinc sulfate flotation following in vitro acid digestion (phase 2 yielded spore numbers adequate for microscopic visualization in

  16. Coregulation of soybean vegetative storage protein gene expression by methyl jasmonate and soluble sugars.

    Science.gov (United States)

    Mason, H S; Dewald, D B; Creelman, R A; Mullet, J E

    1992-03-01

    The soybean vegetative storage protein genes vspA and vspB are highly expressed in developing leaves, stems, flowers, and pods as compared with roots, seeds, and mature leaves and stems. In this paper, we report that physiological levels of methyl jasmonate (MeJA) and soluble sugars synergistically stimulate accumulation of vsp mRNAs. Treatment of excised mature soybean (Glycine max Merr. cv Williams) leaves with 0.2 molar sucrose and 10 micromolar MeJA caused a large accumulation of vsp mRNAs, whereas little accumulation occurred when these compounds were supplied separately. In soybean cell suspension cultures, the synergistic effect of sucrose and MeJA on the accumulation of vspB mRNA was maximal at 58 millimolar sucrose and was observed with fructose or glucose substituted for sucrose. In dark-grown soybean seedlings, the highest levels of vsp mRNAs occurred in the hypocotyl hook, which also contained high levels of MeJA and soluble sugars. Lower levels of vsp mRNAs, MeJA, and soluble sugars were found in the cotyledons, roots, and nongrowing regions of the stem. Wounding of mature soybean leaves induced a large accumulation of vsp mRNAs when wounded plants were incubated in the light. Wounded plants kept in the dark or illuminated plants sprayed with dichlorophenyldimethylurea, an inhibitor of photosynthetic electron transport, showed a greatly reduced accumulation of vsp mRNAs. The time courses for the accumulation of vsp mRNAs induced by wounding or sucrose/MeJA treatment were similar. These results strongly suggest that vsp expression is coregulated by endogenous levels of MeJA (or jasmonic acid) and soluble carbohydrate during normal vegetative development and in wounded leaves.

  17. The role of water radicals in thermorestoration of bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, Y S; Grecz, N [Illinois Inst. of Tech., Chicago (USA). Dept. of Biology

    1974-01-01

    Fully hydrated bacterial spores exposed to 0.45 Mrad showed a characteristic pattern of survival associated with thermorestoration. When temperature during radiation was controlled at -15/sup 0/ to +120/sup 0/C, the lowest viable cell counts were at 0/sup 0/C. Above 0/sup 0/C radiosurvival gradually increased by 2 to 3 log cycles reaching peak at 75/sup 0/C (Bacillus cereus T heat sensitive spores) and at 95/sup 0/C (B.stearothermophilus, heat resistant spores). Simultaneously high survival was observed in the solidly frozen state at -15/sup 0/C to -5/sup 0/C since harmful radicals produced by radiation were trapped in ice. Radiation modifying effects, i.e., protection by 2M ethanol (a scavenger of OH radicals) and sensitization by 1M sodium nitrate (a scavenger of H radicals and hydrated electrons), were studied. The results with ethanol and nitrate confirm the idea that in aqueous sytems below 50/sup 0/C the lethal action is due to oxidizing OH radicals known to attack cell DNA. However, the reversal of scavenger actions above 50/sup 0/C indicates that at those high temperatures lethal effects may also involve the reducing H and esub(aq), which at lower temperatures appear not to affect spore survival though they are known to attack proteins. In this case, it is proposed that radiation inactivation of spores at temperatures below 50/sup 0/C is due to DNA damage inflicted by OH radicals whereas spore death above 50/sup 0/C seems to involve protein /enzyme/ inactivation due to a combined action of heat plus reducing (H, esub(aq)) as well as oxidizing (OH) radical species. From the practical point of view it is important that normally radioprotective effects of such substances as ethanol or ground beef are progressively lost when radiation is carried out at temperatures above 50/sup 0/C.

  18. A method for the determination of bacterial spore DNA content based on isotopic labelling, spore germination and diphenylamine assay; ploidy of spores of several Bacillus species

    International Nuclear Information System (INIS)

    Hauser, P.M.; Karamata, D.

    1992-01-01

    A reliable method for measuring the spore DNA content, based on radioactive DNA labelling, spore germination in absence of DNA replication and diphenylamine assay, was developed. The accuracy of the method, within 10 - 15%, is adequate for determining the number of chromosomes per spore, provided that the genome size is known. B subtilis spores were shown to be invariably monogenomic, while those of larger bacilli Bacillus megaterium, Bacillus cereus and Bacillus thuringiensis, often, if not invariably, contain two genomes. Attempts to modify the spore DNA content of B subtilis by altering the richness of the sporulation medium, the sporulation conditions (liquid or solid medium), or by mutation, were apparently unsuccessful. An increase of spore size with medium richness, not accompanied by an increase in DNA content, was observed. The implication of the apparently species-specific spore ploidy and the influence of the sporulation conditions on spore size and shape are discussed

  19. The role of the acidity of N-heteroaryl sulfonamides as inhibitors of bcl-2 family protein-protein interactions.

    Science.gov (United States)

    Touré, B Barry; Miller-Moslin, Karen; Yusuff, Naeem; Perez, Lawrence; Doré, Michael; Joud, Carol; Michael, Walter; DiPietro, Lucian; van der Plas, Simon; McEwan, Michael; Lenoir, Francois; Hoe, Madelene; Karki, Rajesh; Springer, Clayton; Sullivan, John; Levine, Kymberly; Fiorilla, Catherine; Xie, Xiaoling; Kulathila, Raviraj; Herlihy, Kara; Porter, Dale; Visser, Michael

    2013-02-14

    Overexpression of the antiapoptotic members of the Bcl-2 family of proteins is commonly associated with cancer cell survival and resistance to chemotherapeutics. Here, we describe the structure-based optimization of a series of N-heteroaryl sulfonamides that demonstrate potent mechanism-based cell death. The role of the acidic nature of the sulfonamide moiety as it relates to potency, solubility, and clearance is examined. This has led to the discovery of novel heterocyclic replacements for the acylsulfonamide core of ABT-737 and ABT-263.

  20. On the americium oxalate solubility

    International Nuclear Information System (INIS)

    Zakolupin, S.A.; Korablin, Eh.V.

    1977-01-01

    The americium oxalate solubility at different nitric (0.0-1 M) and oxalic (0.0-0.4 M) acid concentrations was investigated in the temperature range from 14 to 60 deg C. The dependence of americium oxalate solubility on the oxalic acid concentration was determined. Increasing oxalic acid concentration was found to reduce the americium oxalate solubility. The dependence of americium oxalate solubility on the oxalic acid concentration was noted to be a minimum at low acidity (0.1-0.3 M nitric acid). This is most likely due to Am(C 2 O 4 ) + , Am(C 2 O 4 ) 2 - and Am(C 2 O 4 ) 3 3- complex ion formation which have different unstability constants. On the basis of the data obtained, a preliminary estimate was carried out for the product of americium oxalate solubility in nitric acid medium (10 -29 -10 -31 ) and of the one in water (6.4x10 -20 )

  1. Impact of the counterion on the solubility and physicochemical properties of salts of carboxylic acid drugs.

    Science.gov (United States)

    David, S E; Timmins, P; Conway, B R

    2012-01-01

    Salt formation is a widely used approach to improve the physicochemical and solid state properties of an active pharmaceutical ingredient. In order to better understand the relationships between the active drug, the selected counterion and the resultant salt form, crystalline salts were formed using four different carboxylic acid drugs and a closely related series of amine counterions. Thirty-six related crystalline salts were prepared, characterized and the relationship between solubility and dissolution behaviour and other properties of the salt and the counterion studied. Salts of four model acid drugs, gemfibrozil, flurbiprofen, ibuprofen and etodolac were prepared using the counterions butylamine, hexylamine, octylamine, benzylamine, cyclohexylamine, tert-butylamine, 2-amino-2-methylpropan-1-ol, 2-amino-2-methylpropan-1,3-diol and tris(hydroxymethyl)aminomethane. Salt formation was confirmed, the salts were characterized and their corresponding solubilities determined and rationalized with respect to the counterions' properties. The properties of the salt highly dependent on the nature of the counterion and, although there is considerable variation, some general conclusion can be drawn. For the alkyl amines series, increasing chain length leads to a reduction in solubility across all the acidic drugs studied and a reduction in melting point, thus contradicting simplistic relationships between solubility and melting point. Small, compact counterions consistently produce crystalline salts with high melting point accompanied with a modest improvement in solubility and the nature of hydrogen bonding between the ions has a major impact on the solubility.

  2. Analysis of the Effects of a gerP Mutation on the Germination of Spores of Bacillus subtilis

    Science.gov (United States)

    2012-11-01

    REPORT Analysis of the effects of a gerP mutation on the germination of spores of Bacillus subtilis 14. ABSTRACT 16. SECURITY CLASSIFICATION OF... Bacillus subtilis spores with a gerP mutation triggered spore germination via nutrient germinant receptors (GRs) slowly, although this defect was...gerP, Bacillus subtilis , dipicolinic acid Xuan Y. Butzin, Anthony J. Troiano, William H. Coleman, Keren K. Griffiths, Christopher J. Doona, Florence E

  3. Rational identification of aggregation hotspots based on secondary structure and amino acid hydrophobicity.

    Science.gov (United States)

    Matsui, Daisuke; Nakano, Shogo; Dadashipour, Mohammad; Asano, Yasuhisa

    2017-08-25

    Insolubility of proteins expressed in the Escherichia coli expression system hinders the progress of both basic and applied research. Insoluble proteins contain residues that decrease their solubility (aggregation hotspots). Mutating these hotspots to optimal amino acids is expected to improve protein solubility. To date, however, the identification of these hotspots has proven difficult. In this study, using a combination of approaches involving directed evolution and primary sequence analysis, we found two rules to help inductively identify hotspots: the α-helix rule, which focuses on the hydrophobicity of amino acids in the α-helix structure, and the hydropathy contradiction rule, which focuses on the difference in hydrophobicity relative to the corresponding amino acid in the consensus protein. By properly applying these two rules, we succeeded in improving the probability that expressed proteins would be soluble. Our methods should facilitate research on various insoluble proteins that were previously difficult to study due to their low solubility.

  4. Effects of roasting temperatures and gamma irradiation on the content of chlorogenic acid, caffeic acid and soluble carbohydrates of coffee

    International Nuclear Information System (INIS)

    Deshpande, S.N.; Aguilar, A.A.

    1975-01-01

    Two varieties of Puerto Rican coffee, Coffea canephora L. var. Robusta, and Coffea arabica L. var. Borbon, were subjected to four different doses of radiation and roasted at two different temperatures. Aqueous extracts of the ground coffee beans were analyzed for chlorogenic acid and caffeic acid at 324 nm and 360 nm wavelength settings, respectively. Samples subjected to the roasting treatments in conjuction with irradiation treatments were treated with basic lead acetate prior to the colorimetric analyses in order to eliminate interfering substances. The total carbohydrate content was also determined by colorimetric techniques with anthrone reagent. The total nitrogen content of the pulverized samples were determined by the micro-Kjeldahl method. While roasting treatments caused a reduction in the concentrations of the chlorogenic acid, caffeic acid, and the carbohydrates, the radiation treatments increased the concentrations of soluble carbohydrates without affecting the concentrations of chlorogenic acid or caffeic acid. It therefore appears that radiation treatments seem to cause degradation of the acid-polysaccharide complexes liberating soluble sugars. There were no noticable changes in the total content of nitrogen caused by roasting or the radiation treatments as indicated by the statistical analysis employing the split plot design. (author)

  5. Mucorales spores induce a proinflammatory cytokine response in human mononuclear phagocytes and harbor no rodlet hydrophobins.

    Science.gov (United States)

    Wurster, Sebastian; Thielen, Vanessa; Weis, Philipp; Walther, Paul; Elias, Johannes; Waaga-Gasser, Ana Maria; Dragan, Mariola; Dandekar, Thomas; Einsele, Hermann; Löffler, Jürgen; Ullmann, Andrew J

    2017-11-17

    Mucormycoses are life-threatening infections in immunocompromised patients. This study characterizes the response of human mononuclear cells to different Mucorales and Ascomycota. PBMC, monocytes, and monocyte derived dendritic cells (moDCs) from healthy donors were stimulated with resting and germinated stages of Mucorales and Ascomycota. Cytokine response and expression of activation markers were studied. Both inactivated germ tubes and resting spores of Rhizopus arrhizus and other human pathogenic Mucorales species significantly stimulated mRNA synthesis and secretion of proinflammatory cytokines. Moreover, R. arrhizus spores induced the upregulation of co-stimulatory molecules on moDCs and a specific T-helper cell response. Removal of rodlet hydrophobins by hydrofluoric acid treatment of A. fumigatus conidia resulted in enhanced immunogenicity, whereas the cytokine response of PBMCs to dormant R. arrhizus spores was not influenced by hydrofluoric acid. Scanning electron micrographs of Mucorales spores did not exhibit any morphological correlates of rodlet hydrophobins. Taken together, this study revealed striking differences in the response of human mononuclear cells to resting stages of Ascomycota and Mucorales, which may be explained by absence of an immunoprotective hydrophobin layer in Mucorales spores.

  6. Solubility of nickel-cadmium ferrite in acids

    International Nuclear Information System (INIS)

    Vol'ski, V.; Vol'ska, Eh.; Politan'ska, U.

    1977-01-01

    The solubility of a solid solution of nickel-cadmium ferrite containing an excess of ferric oxide, (CdO)sub(0.5), (NiO)sub(0.5) and (Fe 2 O 3 )sub(1.5), in hydrochloric and nitric acids at 20, 40 and 60 deg C, was determined colorimetrically and chelatometrically, as well as by studying the x-ray diffraction patterns of the preparations prior to dissolution and their residues after dissolution. It is shown that cadmium passes into the solution faster than iron and nickel; after 800 hours, the solution contains 40% of iron ions and more than 80% of cadmium ions. The kinetics of ferrite dissolution is studied

  7. Metabolomes of Potato Root Exudates: Compounds That Stimulate Resting Spore Germination of the Soil-Borne Pathogen Spongospora subterranea.

    Science.gov (United States)

    Balendres, Mark A; Nichols, David S; Tegg, Robert S; Wilson, Calum R

    2016-10-12

    Root exudation has importance in soil chemical ecology influencing rhizosphere microbiota. Prior studies reported root exudates from host and nonhost plants stimulated resting spore germination of Spongospora subterranea, the powdery scab pathogen of potato, but the identities of stimulatory compounds were unknown. This study showed that potato root exudates stimulated S. subterranea resting spore germination, releasing more zoospores at an earlier time than the control. We detected 24 low molecular weight organic compounds within potato root exudates and identified specific amino acids, sugars, organic acids, and other compounds that were stimulatory to S. subterranea resting spore germination. Given that several stimulatory compounds are commonly found in exudates of diverse plant species, we support observations of nonhost-specific stimulation. We provide knowledge of S. subterranea resting spore biology and chemical ecology that may be useful in formulating new disease management strategies.

  8. Improving co-amorphous drug formulations by the addition of the highly water soluble amino acid proline

    DEFF Research Database (Denmark)

    Jensen, Katrine Birgitte Tarp; Löbmann, Korbinian; Rades, Thomas

    2014-01-01

    Co-amorphous drug amino acid mixtures were previously shown to be a promising approach to create physically stable amorphous systems with the improved dissolution properties of poorly water-soluble drugs. The aim of this work was to expand the co-amorphous drug amino acid mixture approach...... by combining the model drug, naproxen (NAP), with an amino acid to physically stabilize the co-amorphous system (tryptophan, TRP, or arginine, ARG) and a second highly soluble amino acid (proline, PRO) for an additional improvement of the dissolution rate. Co-amorphous drug-amino acid blends were prepared...... the molecular interactions in the form of hydrogen bonds between all three components in the mixture. A salt formation between the acidic drug, NAP, and the basic amino acid, ARG, was found in co-amorphous NAP–ARG. In comparison to crystalline NAP, binary NAP–TRP and NAP–ARG, it could be shown that the highly...

  9. Nutritional composition and solubility of edible bird nest (Aerodramus fuchiphagus)

    Science.gov (United States)

    Halimi, Nurfatin Mohd; Kasim, Zalifah Mohd; Babji, Abdul Salam

    2014-09-01

    Edible bird nest (EBN) produced by certain swiftlet species mainly, Aerodromus fuciphagus. The objectives of this study were to determine and compare the proximate and amino acid composition of EBN obtained from two regions in Peninsular Malaysia (Pahang-A & Terengganu-B). The solubility of edible bird nest with varying pH, temperature and time was also investigated in this study. The results showed that, the EBN contained crude protein accounted to 58.55% (A) and 55.48% (B), carbohydrate at22.28% (A) & 25.79% (B), moisture content 15.90% (A) & 15.87% (B), fat, 0.67% (A) & and 0.29% (B) and ash contents 2.60% (A) & 2.57% (B) respectively. The major amino acids found in edible bird nest EBN were Glutamic acid (9.61%), Aspartic acid (6.34%), Lysine (5.44 %) and also Leucine (5.30%). The total solubility of EBN was also found to be increased when the temperature was increased increase with distilled water yielding the highest total solubility of EBN compared to others buffer (different pH) solutions.

  10. Enhancement of carvedilol solubility by solid dispersion technique using cyclodextrins, water soluble polymers and hydroxyl acid.

    Science.gov (United States)

    Yuvaraja, K; Khanam, Jasmina

    2014-08-05

    Aim of the present work is to enhance aqueous solubility of carvedilol (CV) by solid dispersion technique using wide variety of carriers such as: β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD), tartaric acid (TA), polyvinyl pyrrolidone K-30 (PVP K-30) and poloxamer-407 (PLX-407). Various products of 'CV-solid dispersion' had been studied extensively in various pH conditions to check enhancement of solubility and dissolution characteristics of carvedilol. Any physical change upon interaction between CV and carriers was confirmed by instrumental analysis: XRD, DSC, FTIR and SEM. Negative change of Gibb's free energy and complexation constants (Kc, 75-240M(-1), for cyclodextrins and 1111-20,365M(-1), for PVP K-30 and PLX-407) were the evidence of stable nature of the binding between CV and carriers. 'Solubility enhancement factor' of ionized-CV was found high enough (340 times) with HPβCD in presence of TA. TA increases the binding efficiency of cyclodextrin and changing the pH of microenvironment in dissolution medium. In addition, ionization process was used to increase the apparent intrinsic solubility of drug. In vitro, dissolution time of CV was remarkably reduced in the solid dispersion system compared to that of pure drug. This may be attributed to increased wettability, dispersing ability and transformation of crystalline state of drug to amorphous one. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Melamine and Cyanuric Acid do not interfere with Bradford and Ninhydrin assays for protein determination.

    Science.gov (United States)

    Field, Anjalie; Field, Jeffrey

    2010-08-01

    In the fall of 2007 pet food contaminated with melamine and cyanuric acid caused kidney stones in thousands of animals. In the summer of 2008, a more serious outbreak of adulterated dairy food caused the deaths of six infants and sickened about 290,000 children in China. In all cases, melamine was likely added to inflate the apparent protein content of the foods. To determine if we could measure protein without interference from melamine and cyanuric acid we tested these compounds in the Bradford and Ninhydrin assays, two common dye-based assays for protein, as well as by ammonia release, the most common assay used in the food industry. Neither compound was detected in the Ninhydrin and Bradford assays at concentrations of >100 μg/ml. The ammonia assay detected melamine but was inconclusive with respect to cyanuric acid. To develop an accurate test for food that would not detect either chemical as a protein, assays were run on cat food and reconstituted milk powder. The Bradford assay readily measured the protein content of each food, and importantly, the addition of melamine or cyanuric acid to reconstituted milk did not affect the readings. The protein concentrations obtained for reconstituted milk powder were as expected, but those for the cat food were 10 to 30-fold lower, due to its low solubility. We conclude that dye-binding assays can be employed to detect protein in food without interference from melamine and cyanuric acid, thus reducing the incentive to use them as additives.

  12. Compositional changes of proteins and amino acids in germinating coffee seeds

    Directory of Open Access Journals (Sweden)

    Milton Massao Shimizu

    2000-01-01

    Full Text Available Endosperm is the main reserve tissue in coffee seeds. Coffee (Coffea arabica L. seeds were germinated for six weeks and qualitative and quantitative changes in amino acids and proteins were investigated. The total content of free amino acids were reduced during germination, however, protein content remained constant. SDS-PAGE profiles showed that legumin-like proteins became less stained in the last weeks. Asparagine, glutamic acid, aspartic acid, alanine and lysine were the major free amino acids, although serine and glutamine were also significant. Except for tyrosine, which increased with germination, all other amino acids were reduced. Analysis of the amino acid composition of the total soluble protein showed glutamic acid/glutamine and glycine as the main amino acids. However, other amino acids such as leucine, aspartic acid/asparagine, alanine, lysine, serine were also found in reasonable amounts.Endosperma é o principal tecido de reserva em sementes de café. Sementes de café (Coffea arabica L. foram germinadas por seis semanas e as alterações qualitativas e quantitativas de aminoácidos e proteínas foram investigadas. O conteúdo total de aminoácidos livres reduziu durante a germinação, no entanto, o conteúdo de proteínas permaneceu constante. Perfis eletroforéticos de proteínas em SDS-PAGE mostraram que proteínas do tipo legumina foram menos coradas nas últimas semanas. Asparagina, ácido glutâmico, ácido aspártico, alanina e lisina foram os principais aminoácidos, apesar de que serina e glutamina também estavam presentes em quantidades significativas. Exceto tirosina, a qual aumentou durante a germinação, todos os outros aminoácidos tiveram redução em sua concentração. A análise aminoacídica da fração de proteína solúvel total mostrou que ácido glutâmico/glutamina e glicina eram os principais aminoácidos presentes. No entanto, outros aminoácidos, tais como leucina, ácido asp

  13. Fifth international fungus spore conference

    Energy Technology Data Exchange (ETDEWEB)

    Timberlake, W.E.

    1993-04-01

    This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

  14. Prokaryotic Soluble Overexpression and Purification of Human VEGF165 by Fusion to a Maltose Binding Protein Tag.

    Directory of Open Access Journals (Sweden)

    Minh Tan Nguyen

    Full Text Available Human vascular endothelial growth factor (VEGF is a key regulator of angiogenesis and plays a central role in the process of tumor growth and metastatic dissemination. Escherichia coli is one of the most common expression systems used for the production of recombinant proteins; however, expression of human VEGF in E. coli has proven difficult because the E. coli-expressed VEGF tends to be misfolded and forms inclusion bodies, resulting in poor solubility. In this study, we successfully produced semi-preparative amounts of soluble bioactive human VEGF165 (hVEGF. We created seven N-terminal fusion tag constructs with hexahistidine (His6, thioredoxin (Trx, glutathione S-transferase (GST, maltose-binding protein (MBP, N-utilization substance protein A (NusA, human protein disulfide isomerase (PDI, and the b'a' domain of PDI (PDIb'a', and tested each construct for soluble overexpression in E. coli. We found that at 18°C, 92.8% of the MBP-tagged hVEGF to be soluble and that this tag significantly increased the protein's solubility. We successfully purified 0.8 mg of pure hVEGF per 500 mL cell culture. The purified hVEGF is stable after tag cleavage, contains very low levels of endotoxin, and is 97.6% pure. Using an Flk1+ mesodermal precursor cell (MPC differentiation assay, we show that the purified hVEGF is not only bioactive but has similar bioactivity to hVEGF produced in mammalian cells. Previous reports on producing hVEGF in E. coli have all been based on refolding of the protein from inclusion bodies. To our knowledge, this is the first report on successfully expressing and purifying soluble hVEGF in E. coli.

  15. Photodamaging mechanism of the eye structure: UV effect on soluble proteins of the lens

    International Nuclear Information System (INIS)

    Korkhmazyan, M.M.; Fedorovich, I.B.; Ostrovskij, M.A.

    1983-01-01

    Damaging effect of UV-radiation on soluble proteins of bull lens has been studied. Irradiation results in lens proteins growing yellow, new absorption bands with the maxima 245 and 305 nm appear. It is shown that during photodamage oxidation of SH-groups takes place and protein aggregates are formed

  16. Ascorbic acid glycation of lens proteins produces UVA sensitizers similar to those in human lens

    International Nuclear Information System (INIS)

    Ortwerth, B.J.; Linetsky, Mikhail; Olesen, P.R.

    1995-01-01

    Soluble calf lens proteins were extensively glycated during a 4 week incubation with ascorbic acid in the presence of oxygen. Amino acids analysis of the dialyzed proteins removed at weekly intervals showed an increasing loss of lysine, arginine and histidine, consistent with the extensive protein cross-linking observed. Irradiation of the dialyzed samples with UVA light (1.0 kJ/cm 2 total illumination through a 338 nm cutoff filter) caused an increasing loss of tryptophan, an additional loss of histidine and the production of micromolar concentrations of hydrogen peroxide. No alteration in amino acid content and no photolytic effects were seen in proteins incubated without ascorbic acid in proteins incubated with glucose for 4 weeks. The rate of hydrogen peroxide formation was linear with each glycated sample with a maximum production of 25 nmol/mg protein illuminated. The possibility that the sensitizer activity was due to an ascorbate-induced oxidation of tryptophan was eliminated by the presence of a heavy metal ion chelator during the incubation and by showing equivalent effects with ascorbate-incubated ribonuclease A, which is devoid of tryptophan. The ascorbate-incubated samples displayed increasing absorbance at wavelengths above 300 nm and increasing fluorescence (340/430) as glycation proceeded. The spectra of the 4 week glycated proteins were identical to those obtained with a solubilized water-insoluble fraction from human lens, which is known to have UVA sensitizer activity. (Author)

  17. Ultrastructure and properties of Paecilomyces lilacinus spores

    Energy Technology Data Exchange (ETDEWEB)

    Holland, R.J.; Gunasekera, T.S. [Macquarie Univ., Dept. of Biological Sciences, Sydney (Australia); Williams, K.L. [Proteome Systems Ltd., Sydney (Australia); Nevalainen, K.M.H. [Dept. of Biological Sciences, Macquarie University, Sydney (Australia)

    2002-10-01

    Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

  18. Ultrastructure and properties of Paecilomyces lilacinus spores

    International Nuclear Information System (INIS)

    Holland, R.J.; Gunasekera, T.S.; Williams, K.L.; Nevalainen, K.M.H.

    2002-01-01

    Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

  19. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    Science.gov (United States)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  20. [Comparative characteristics of the amino acid composition of the protein fractions of the hydrogen bacteria Hydrogenomonas eutropha in meat and wheat].

    Science.gov (United States)

    Barashkov, V A; Trubachev, I N; Gitel'zon, I I

    1976-01-01

    An attempt was made to compare the biological value of the biological mass of the hydrogen bacteria Tydrogenomas eutropha, of meat and wheat on the ground of the fractional and amino acids composition of their proteins. Substantial differences in the distribution of proteins and amino acids in all of the three objects examined were revealed. It is shown that more than one half of the entire protein contained in the biological mass of the hydrogen bacteria is made up of poorly soluble structural proteins difficultly amenable to the action of digestive enzymes. It is this fraction where the bulk of essential amino acids is concentrated. The data obtained imply that the biological value of the biological mass of hydrogen bacteria is higher than in wheat, but lower than in meat.

  1. Benzoate-mediated changes on expression profile of soluble proteins in Serratia sp. DS001.

    Science.gov (United States)

    Pandeeti, E V P; Chinnaboina, M R; Siddavattam, D

    2009-05-01

    To assess differences in protein expression profile associated with shift in carbon source from succinate to benzoate in Serratia sp. DS001 using a proteomics approach. A basic proteome map was generated for the soluble proteins extracted from Serratia sp. DS001 grown in succinate and benzoate. The differently and differentially expressed proteins were identified using ImageMaster 2D Platinum software (GE Healthcare). The identity of the proteins was determined by employing MS or MS/MS. Important enzymes such as Catechol 1,2 dioxygenase and transcriptional regulators that belong to the LysR superfamily were identified. Nearly 70 proteins were found to be differentially expressed when benzoate was used as carbon source. Based on the protein identity and degradation products generated from benzoate it is found that ortho pathway is operational in Serratia sp. DS001. Expression profile of the soluble proteins associated with shift in carbon source was mapped. The study also elucidates degradation pathway of benzoate in Serratia sp. DS001 by correlating the proteomics data with the catabolites of benzoate.

  2. Investigation of spore coat display of Bacillus subtilis β-galactosidase for developing of whole cell biocatalyst.

    Science.gov (United States)

    Tavassoli, Setareh; Hinc, Krzysztof; Iwanicki, Adam; Obuchowski, Michal; Ahmadian, Gholamreza

    2013-03-01

    The production of highly efficient, recyclable and cost-effective enzymes is one of the most important goals in industrial biotechnology. Bacterial spores are highly resistant to harsh environmental conditions, easy to produce and are suitable for manipulation of genetic materials. These features make them a very efficient tool for biotechnology. Here, we show the use bacterial spores for presentation of functional enzyme. Spore coat display was used to produce a biocatalyst, which expresses β-galactiosidase (LacA). This enzyme is commonly used to produce lactose-free milk for lactose intolerant individuals. The lacA gene from Bacillus subtilis strain 168 was expressed on the surface of B. subtilis RH101(ΔcotC) spores using CotC as protein carrier. Presence of LacA protein is verified by western blotting. Results of β-galactiosidase assay show that the expressed enzyme retained its activity in condition of freezing and drying, as well as after recovery from the reaction's mixture.

  3. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  4. A potential new selection criterion for breeding winter barley optimal protein and amino acid profiles for liquid pig feed

    DEFF Research Database (Denmark)

    Christensen, Jesper Bjerg; Blaabjerg, Karoline; Poulsen, Hanne Damgaard

    The hypothesis is that cereal proteases in liquid feed degrade and convert water insoluble storage protein into water soluble protein, which may improve the digestibility of protein in pigs compared with dry feeding. Protein utilization is increased by matching the amino acid (AAs) content...... of the diet as close as possible to the pigs’ requirement. By improving the availability of isoleucine, leucine, histidine and phenylalanine, which are limiting and commercial unavailable, the amount of crude protein in the pig feed can be reduced, resulting in a decreased excretion of nitrogen. The aim...... of glutamic acid revealed differences between the cultivars and the solubilised protein at all three times. These preliminary results may indicate that improvements of the nitrogen utilization in pigs fed soaked winter barley depends on the choice of cultivar and soaking time, and may serve as a new selection...

  5. Soluble lens protein polymorphism in flying fishes from the central Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.

    Soluble eye lens nuclei proteins of flying-fishes were studied by cellogel electrophoresis. Three distinct patterns characterized by the number of bands, mobility and staining intensity were observed. Morphological studies of these fishes showed...

  6. Prefoldin Promotes Proteasomal Degradation of Cytosolic Proteins with Missense Mutations by Maintaining Substrate Solubility.

    Directory of Open Access Journals (Sweden)

    Sophie A Comyn

    2016-07-01

    Full Text Available Misfolded proteins challenge the ability of cells to maintain protein homeostasis and can accumulate into toxic protein aggregates. As a consequence, cells have adopted a number of protein quality control pathways to prevent protein aggregation, promote protein folding, and target terminally misfolded proteins for degradation. In this study, we employed a thermosensitive allele of the yeast Guk1 guanylate kinase as a model misfolded protein to investigate degradative protein quality control pathways. We performed a flow cytometry based screen to identify factors that promote proteasomal degradation of proteins misfolded as the result of missense mutations. In addition to the E3 ubiquitin ligase Ubr1, we identified the prefoldin chaperone subunit Gim3 as an important quality control factor. Whereas the absence of GIM3 did not impair proteasomal function or the ubiquitination of the model substrate, it led to the accumulation of the poorly soluble model substrate in cellular inclusions that was accompanied by delayed degradation. We found that Gim3 interacted with the Guk1 mutant allele and propose that prefoldin promotes the degradation of the unstable model substrate by maintaining the solubility of the misfolded protein. We also demonstrated that in addition to the Guk1 mutant, prefoldin can stabilize other misfolded cytosolic proteins containing missense mutations.

  7. Photometric immersion refractometry of bacterial spores.

    Science.gov (United States)

    Gerhardt, P; Beaman, T C; Corner, T R; Greenamyre, J T; Tisa, L S

    1982-01-01

    Photometric immersion refractometry was used to determine the average apparent refractive index (n) of five types of dormant Bacillus spores representing a 600-fold range in moist-heat resistance determined as a D100 value. The n of a spore type increased as the molecular size of various immersion solutes decreased. For comparison of the spore types, the n of the entire spore and of the isolated integument was determined by use of bovine serum albumin, which is excluded from permeating into them. The n of the sporoplast (the structures bounded by the outer pericortex membrane) was determined by use of glucose, which was shown to permeate into the spore only as deeply as the pericortex membrane. Among the various spore types, an exponential increase in the heat resistance correlated with the n of the entire spore and of the sporoplast, but not of the isolated perisporoplast integument. Correlation of the n with the solids content of the entire spore provided a method of experimentally obtaining the refractive index increment (dn/dc), which was constant for the various spore types and enables the calculation of solids and water content from an n. Altogether, the results showed that the total water content is distributed unequally within the dormant spore, with less water in the sporoplast than in the perisporoplast integument, and that the sporoplast becomes more refractile and therefore more dehydrated as the heat resistance becomes greater among the various spore types. PMID:6802796

  8. Prokaryotic soluble overexpression and purification of bioactive human growth hormone by fusion to thioredoxin, maltose binding protein, and protein disulfide isomerase.

    Directory of Open Access Journals (Sweden)

    Minh Tan Nguyen

    Full Text Available Human growth hormone (hGH is synthesized by somatotroph cells of the anterior pituitary gland and induces cell proliferation and growth. This protein has been approved for the treatment of various conditions, including hGH deficiency, chronic renal failure, and Turner syndrome. Efficient production of hGH in Escherichia coli (E. coli has proven difficult because the E. coli-expressed hormone tends to aggregate and form inclusion bodies, resulting in poor solubility. In this study, seven N-terminal fusion partners, hexahistidine (His6, thioredoxin (Trx, glutathione S-transferase (GST, maltose-binding protein (MBP, N-utilization substance protein A (NusA, protein disulfide bond isomerase (PDI, and the b'a' domain of PDI (PDIb'a', were tested for soluble overexpression of codon-optimized hGH in E. coli. We found that MBP and hPDI tags significantly increased the solubility of the hormone. In addition, lowering the expression temperature to 18°C also dramatically increased the solubility of all the fusion proteins. We purified hGH from MBP-, PDIb'a'-, or Trx-tagged hGH expressed at 18°C in E. coli using simple chromatographic techniques and compared the final purity, yield, and activity of hGH to assess the impact of each partner protein. Purified hGH was highly pure on silver-stained gel and contained very low levels of endotoxin. On average, ∼37 mg, ∼12 mg, and ∼7 mg of hGH were obtained from 500 mL-cell cultures of Trx-hGH, MBP-hGH, and PDIb'a'-hGH, respectively. Subsequently, hGH was analyzed using mass spectroscopy to confirm the presence of two intra-molecular disulfide bonds. The bioactivity of purified hGHs was demonstrated using Nb2-11 cell.

  9. Mechanism of the hydrolysis of 4-methylumbelliferyl-beta-D-glucoside by germinating and outgrowing spores of Bacillus species.

    Science.gov (United States)

    Setlow, B; Cabrera-Martinez, R-M; Setlow, P

    2004-01-01

    To determine the mechanism of the hydrolysis of 4-methylumbelliferyl-beta-D-glucopyranoside (beta-MUG) by germinating and outgrowing spores of Bacillus species. Spores of B. atrophaeus (formerly B. subtilis var. niger, Fritze and Pukall 2001) are used as biological indicators of the efficacy of ethylene oxide sterilization by measurement of beta-MUG hydrolysis during spore germination and outgrowth. It was previously shown that beta-MUG is hydrolysed to 4-methylumbelliferone (MU) during the germination and outgrowth of B. atrophaeus spores (Chandrapati and Woodson 2003), and this was also the case with spores of B. subtilis 168. Germination of spores of either B. atrophaeus or B. subtilis with chloramphenicol reduced beta-MUG hydrolysis by almost 99%, indicating that proteins needed for rapid beta-MUG hydrolysis are synthesized during spore outgrowth. However, the residual beta-MUG hydrolysis during spore germination with chloramphenicol indicated that dormant spores contain low levels of proteins needed for beta-MUG uptake and hydrolysis. With B. subtilis 168 spores that lacked several general proteins of the phosphotransferase system (PTS) for sugar uptake, beta-MUG hydrolysis during spore germination and outgrowth was decreased >99.9%. This indicated that beta-MUG is taken up by the PTS, resulting in the intracellular accumulation of the phosphorylated form of beta-MUG, beta-MUG-6-phosphate (beta-MUG-P). This was further demonstrated by the lack of detectable glucosidase activity on beta-MUG in dormant, germinated and outgrowing spore extracts, while phosphoglucosidase active on beta-MUG-P was readily detected. Dormant B. subtilis 168 spores had low levels of at least four phosphoglucosidases active on beta-MUG-P: BglA, BglH, BglC (originally called YckE) and BglD (originally called YdhP). These enzymes were also detected in spores germinating and outgrowing with beta-MUG, but levels of BglH were the highest, as this enzyme's synthesis was induced ca 100-fold

  10. Improving the water solubility of Monascus pigments under acidic conditions with gum arabic.

    Science.gov (United States)

    Jian, Wenjie; Sun, Yuanming; Wu, Jian-Yong

    2017-07-01

    Monascus pigments (Mps) are natural food colorants and their stability in acidic solutions is important for application in the food industry. This study aimed to evaluate the use of gum arabic (GA) as a stabilizer for maintaining the solubility of Mps in an acidic aqueous solution exposed to a high temperature, and to analyze the molecular interactions between GA and Mps. Mps dispersed (0.2 g kg -1 ) in deionized water at pH 3.0-4.0 without GA formed precipitates but remained in a stable solution in the presence of GA (1 g kg -1 ). The significant improvement of Mps water solubility under acidic conditions was attributed to the formation of Mps-GA complexes, as indicated by a sharp increase in the fluorescence intensity. The results on particle size, zeta potential, and transmission electron microscopy further suggested that molecular binding of Mps to GA, electrostatic repulsion, and steric hindrance of GA were contributing factors to preventing the aggregation of Mps in acidic solutions. A mechanistic model was presented for GA-Mps interactions and complex structures. GA was proven to be an effective stabilizer of natural food colorants in acidic solutions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. ESPRIT: an automated, library-based method for mapping and soluble expression of protein domains from challenging targets.

    Science.gov (United States)

    Yumerefendi, Hayretin; Tarendeau, Franck; Mas, Philippe J; Hart, Darren J

    2010-10-01

    Expression of sufficient quantities of soluble protein for structural biology and other applications is often a very difficult task, especially when multimilligram quantities are required. In order to improve yield, solubility or crystallisability of a protein, it is common to subclone shorter genetic constructs corresponding to single- or multi-domain fragments. However, it is not always clear where domain boundaries are located, especially when working on novel targets with little or no sequence similarity to other proteins. Several methods have been described employing aspects of directed evolution to the recombinant expression of challenging proteins. These combine the construction of a random library of genetic constructs of a target with a screening or selection process to identify solubly expressing protein fragments. Here we review several datasets from the ESPRIT (Expression of Soluble Proteins by Random Incremental Truncation) technology to provide a view on its capabilities. Firstly, we demonstrate how it functions using the well-characterised NF-kappaB p50 transcription factor as a model system. Secondly, application of ESPRIT to the challenging PB2 subunit of influenza polymerase has led to several novel atomic resolution structures; here we present an overview of the screening phase of that project. Thirdly, analysis of the human kinase TBK1 is presented to show how the ESPRIT technology rapidly addresses the compatibility of challenging targets with the Escherichia coli expression system.

  12. Synergistic enhancement in the co-gelation of salt-soluble pea proteins and whey proteins.

    Science.gov (United States)

    Wong, Douglas; Vasanthan, Thava; Ozimek, Lech

    2013-12-15

    This paper investigated the enhancement of thermal gelation properties when salt-soluble pea proteins were co-gelated with whey proteins in NaCl solutions, using different blend ratios, total protein concentrations, pH, and salt concentrations. Results showed that the thermal co-gelation of pea/whey proteins blended in ratio of 2:8 in NaCl solutions showed synergistic enhancement in storage modulus, gel hardness, paste viscosity and minimum gelation concentrations. The highest synergistic enhancement was observed at pH 6.0 as compared with pH 4.0 and 8.0, and at the lower total protein concentration of 10% as compared with 16% and 22% (w/v), as well as in lower NaCl concentrations of 0.5% and 1.0% as compared with 1.5%, 2.0%, 2.5%, and 3.0% (w/v). The least gelation concentrations were also lower in the different pea/whey protein blend ratios than in pure pea or whey proteins, when dissolved in 1.0% or 2.5% (w/v) NaCl aqueous solutions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Spores of most common airborne fungi reveal no ice nucleation activity

    Science.gov (United States)

    Pummer, B. G.; Atanasova, L.; Bauer, H.; Bernardi, J.; Druzhinina, I. S.; Grothe, H.

    2013-06-01

    Fungal spores are ubiquitous biological aerosols, which are considered to show ice nucleation (IN) activity. In this study the respective IN activity was tested in oil emulsion in the immersion freezing mode. The focus was laid on species of economical, ecological or sanitary significance. For the first time, not only common moulds, but also edible mushrooms (Basidiomycota, Agaricomycetes) were investigated, as they contribute massively to the total amount of fungal spores in the atmosphere. Only Fusarium avenaceum showed freezing events at low subzero-temperatures, while the other investigated fungal spores showed no significant IN activity. Furthermore, we selected a set of fungal strains from different sites and exposed them to occasional freezing stress during cultivation. Although the total protein expression was altered by this treatment, it had no significant impact on the IN activity.

  14. Phthalic Acid Chemical Probes Synthesized for Protein-Protein Interaction Analysis

    Directory of Open Access Journals (Sweden)

    Chin-Jen Wu

    2013-06-01

    Full Text Available Plasticizers are additives that are used to increase the flexibility of plastic during manufacturing. However, in injection molding processes, plasticizers cannot be generated with monomers because they can peel off from the plastics into the surrounding environment, water, or food, or become attached to skin. Among the various plasticizers that are used, 1,2-benzenedicarboxylic acid (phthalic acid is a typical precursor to generate phthalates. In addition, phthalic acid is a metabolite of diethylhexyl phthalate (DEHP. According to Gene_Ontology gene/protein database, phthalates can cause genital diseases, cardiotoxicity, hepatotoxicity, nephrotoxicity, etc. In this study, a silanized linker (3-aminopropyl triethoxyslane, APTES was deposited on silicon dioxides (SiO2 particles and phthalate chemical probes were manufactured from phthalic acid and APTES–SiO2. These probes could be used for detecting proteins that targeted phthalic acid and for protein-protein interactions. The phthalic acid chemical probes we produced were incubated with epithelioid cell lysates of normal rat kidney (NRK-52E cells to detect the interactions between phthalic acid and NRK-52E extracted proteins. These chemical probes interacted with a number of chaperones such as protein disulfide-isomerase A6, heat shock proteins, and Serpin H1. Ingenuity Pathways Analysis (IPA software showed that these chemical probes were a practical technique for protein-protein interaction analysis.

  15. Soluble expression of recombinant proteins in the cytoplasm of Escherichia coli

    DEFF Research Database (Denmark)

    Sørensen, Hans; Mortensen, Kim

    2005-01-01

    Pure, soluble and functional proteins are of high demand in modern biotechnology. Natural protein sources rarely meet the requirements for quantity, ease of isolation or price and hence recombinant technology is often the method of choice. Recombinant cell factories are constantly employed...... molecular tools available. In spite of all these qualities, expression of recombinant proteins with E. coli as the host often results in insoluble and/or nonfunctional proteins. Here we review new approaches to overcome these obstacles by strategies that focus on either controlled expression of target...... for the production of protein preparations bound for downstream purification and processing. Eschericia coli is a frequently used host, since it facilitates protein expression by its relative simplicity, its inexpensive and fast high density cultivation, the well known genetics and the large number of compatible...

  16. Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Stanford, Lateefah A; Kim, Sunghwan; Klein, Geoffrey C; Smith, Donald F; Rodgers, Ryan P; Marshall, Alan G

    2007-04-15

    We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2.

  17. Chemical constituents: water-soluble vitamins, free amino acids and sugar profile from Ganoderma adspersum.

    Science.gov (United States)

    Kıvrak, İbrahim

    2015-01-01

    Ganoderma adspersum presents a rigid fruiting body owing to chitin content and having a small quantity of water or moisture. The utility of bioactive constituent of the mushroom can only be available by extraction for human usage. In this study, carbohydrate, water-soluble vitamin compositions and amino acid contents were determined in G. adspersum mushroom. The composition in individual sugars was determined by HPLC-RID, mannitol (13.04 g/100 g) and trehalose (10.27 g/100 g) being the most abundant sugars. The examination of water-soluble vitamins and free amino acid composition was determined by UPLC-ESI-MS/MS. Essential amino acid constituted 67.79% of total amino acid, which is well worth the attention with regard to researchers and consumers. In addition, G. adspersum, which is also significantly rich in B group vitamins and vitamin C, can provide a wide range of notable applications in the pharmaceutics, cosmetics, food and dietary supplement industries. G. adspersum revealed its value for pharmacy and nutrition fields.

  18. In vitro versus in vivo protein digestibility techniques for calculating PDCAAS (protein digestibility-corrected amino acid score) applied to chickpea fractions.

    Science.gov (United States)

    Tavano, Olga Luisa; Neves, Valdir Augusto; da Silva Júnior, Sinézio Inácio

    2016-11-01

    Seven different in vitro methods to determine the protein digestibility for chickpea proteins were considered and also the application of these methodologies for calculating PDCAAS (protein digestibility-corrected amino acid score), seeking their correlations with the in vivo methodology. In vitro digestibility of raw and heated samples were determined using pepsin-pancreatin hydrolysis, considering soluble nitrogen via Kjeldahl (ppKJ) and hydrolysed peptide linkages using trinitrobenzenesulfonic acid and o-phthaldialdehyde. In vitro digestibility was also determined using trypsin, chymotrypsin and peptidase (3-Enz) or trypsin, chymotrypsin, peptidase and pronase solution (4-Enz). None of the correlations between in vitro and in vivo digestibilities were significant (at p<0.0500), but, strong correlations were observed between PDCAAS calculated by in vitro and in vivo results. PDCAAS-ppKJ, PDCAAS-3-Enz and PDCAAS-4-Enz presented the highest correlations with in vivo method, r=0.9316, 0.9442 and 0.9649 (p<0.0500), respectively. The use of in vitro methods for calculating PDCAAS may be promising and deserves more discussions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. The nature of water within bacterial spores: protecting life in extreme environments

    Science.gov (United States)

    Rice, Charles V.; Friedline, Anthony; Johnson, Karen; Zachariah, Malcolm M.; Thomas, Kieth J., III

    2011-10-01

    The bacterial spore is a formidable container of life, protecting the vital contents from chemical attack, antimicrobial agents, heat damage, UV light degradation, and water dehydration. The exact role of the spore components remains in dispute. Nevertheless, water molecules are important in each of these processes. The physical state of water within the bacterial spore has been investigated since the early 1930's. The water is found two states, free or bound, in two different areas, core and non-core. It is established that free water is accessible to diffuse and exchange with deuterated water and that the diffusible water can access all areas of the spore. The presence of bound water has come under recent scrutiny and has been suggested the water within the core is mobile, rather than bound, based on the analysis of deuterium relaxation rates. Using an alternate method, deuterium quadrupole-echo spectroscopy, we are able to distinguish between mobile and immobile water molecules. In the absence of rapid motion, the deuterium spectrum of D2O is dominated by a broad line, whose line shape is used as a characteristic descriptor of molecular motion. The deuterium spectrum of bacterial spores reveals three distinct features: the broad peak of immobilized water, a narrow line of water in rapid motion, and a signal of intermediate width. This third signal is assigned this peak from partially deuterated proteins with the spore in which N-H groups have undergone exchange with water deuterons to form N-D species. As a result of these observations, the nature of water within the spore requires additional explanation to understand how the spore and its water preserve life.

  20. Redox potentials and kinetics of the Ce 3+/Ce 4+ redox reaction and solubility of cerium sulfates in sulfuric acid solutions

    Science.gov (United States)

    Paulenova, A.; Creager, S. E.; Navratil, J. D.; Wei, Y.

    Experimental work was performed with the aim of evaluating the Ce 4+/Ce 3+ redox couple in sulfuric acid electrolyte for use in redox flow battery (RFB) technology. The solubility of cerium sulfates in 0.1-4.0 M sulfuric acid at 20-60 °C was studied. A synergistic effect of both sulfuric acid concentration and temperature on the solubility of cerous sulfate was observed. The solubility of cerous sulfate significantly decreased with rising concentration of sulfuric acid and rising temperature, while the solubility of ceric sulfate goes through a significant maximum at 40 °C. Redox potentials and the kinetics of the cerous/ceric redox reaction were also studied under the same temperature-concentration conditions. The redox potentials were measured using the combined redox electrode (Pt-Ag/AgCl) in equimolar Ce 4+/Ce 3+ solutions (i.e.[Ce 3+]=[Ce 4+]) in sulfuric acid electrolyte. The Ce 3+/Ce 4+ redox potentials significantly decrease (i.e. shift to more negative values) with rising sulfuric acid concentration; a small maximum is observed at 40 °C. Cyclic voltammetric experiments confirmed slow electrochemical kinetics of the Ce 3+/Ce 4+ redox reaction on carbon glassy electrodes (CGEs) in sulfuric acid solutions. The observed dependencies of solubilities, the redox potentials and the kinetics of Ce 3+/Ce 4+ redox reaction on sulfuric acid concentration are thought to be the result of inequivalent complexation of the two redox species by sulfate anions: the ceric ion is much more strongly bound to sulfate than is the cerous ion. The best temperature-concentration conditions for the RFB electrolytes appear to be 40 °C and 1 M sulfuric acid, where the relatively good solubility of both cerium species, the maximum of redox potentials, and the more or less satisfying stability of CGE s were found. Even so, the relatively low solubility of cerium salts in sulfuric acid media and slow redox kinetics of the Ce 3+/Ce 4+ redox reaction at carbon indicate that the Ce 3+/Ce

  1. An autoclave treatment reduces the solubility and antigenicity of an allergenic protein found in buckwheat flour.

    Science.gov (United States)

    Tomotake, Hiroyuki; Yamazaki, Rikio; Yamato, Masayuki

    2012-06-01

    The effects of an autoclave treatment of buckwheat flour on a 24-kDa allergenic protein were investigated by measuring reduction in solubility and antibody binding. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the intensity of the major bands, including that of the 24-kDa allergen, was reduced by the autoclave treatment. The protein solubility in buckwheat flour was variably decreased by the autoclave treatment. Enzyme-linked immunosorbent assay analysis using a monoclonal antibody specific for buckwheat 24-kDa protein showed that the reactivity of protein extracts (10 μg/ml) from buckwheat flour was lowered by the autoclave treatment. The autoclave treatment may reduce the major allergen content of buckwheat. Future studies will determine if autoclaving treatments affect the allergenicity of the 24-kDa buckwheat protein.

  2. Presenting Influenza A M2e Antigen on Recombinant Spores of Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Tomasz Łęga

    Full Text Available Effective vaccination against influenza virus infection is a serious problem mainly due to antigenic variability of the virus. Among many of investigated antigens, the extracellular domain of the M2 protein (M2e features high homology in all strains of influenza A viruses and antibodies against M2e and is protective in animal models; this makes it a potential candidate for generation of a universal influenza vaccine. However, due to the low immunogenicity of the M2e, formulation of a vaccine based on this antigen requires some modification to induce effective immune responses. In this work we evaluated the possible use of Bacillus subtilis spores as a carrier of the Influenza A M2e antigen in mucosal vaccination. A tandem repeat of 4 consensus sequences coding for human-avian-swine-human M2e (M2eH-A-S-H peptide was fused to spore coat proteins and stably exposed on the spore surface, as demonstrated by the immunostaining of intact, recombinant spores. Oral immunization of mice with recombinant endospores carrying M2eH-A-S-H elicited specific antibody production without the addition of adjuvants. Bacillus subtilis endospores can serve as influenza antigen carriers. Recombinant spores constructed in this work showed low immunogenicity although were able to induce antibody production. The System of influenza antigen administration presented in this work is attractive mainly due to the omitting time-consuming and cost-intensive immunogen production and purification. Therefore modification should be made to increase the immunogenicity of the presented system.

  3. Maternal parentage influences spore production but not spore pigmentation in the anisogamous and hermaphroditic fungus Neurospora crassa

    DEFF Research Database (Denmark)

    Zimmerman, Kolea; Levitis, Daniel; Pringle, Anne

    2014-01-01

    . In this fungus, pigmented spores are viable and unpigmented spores are inviable. These results show that while both parents influence all these traits, maternal influence is strongest on both fertility and mortality traits until the spores are physiologically independent of the maternal cytoplasm.......In this study, we tested the hypothesis that maternal effects on offspring production and quality are greater than paternal effects in both offspring number (fertility) and offspring viability (mortality). We used the model filamentous fungus Neurospora crassa. This fungus is anisogamous......, and various ascospore characteristics. Mixed effects models of these data show that the female parent accounts for the majority of variation in perithecial production, number of spores produced, and spore germination. Surprisingly, both sexes equally influence the percentage of spores that are pigmented...

  4. The Luna stain, an improved selective stain for detection of microsporidian spores in histologic sections

    Science.gov (United States)

    Peterson, Tracy S.; Spitsbergen, Jan M.; Feist, Stephen W.; Kent, Michael L.

    2014-01-01

    Microsporidia in histologic sections are most often diagnosed by observing spores in host tissues. Spores are easy to identify if they occur in large aggregates or xenomas when sections are stained with hematoxylin and eosin (H&E). However, individual spores are not frequently detected in host tissues with conventional H&E staining, particularly if spores are scattered within the tissues, areas of inflammation or small spores in nuclei (i.e., Nucleospora salmonis). Hence, a variety of selective stains that enhance visualization of spores are recommended. We discovered that the Luna stain, used to highlight eosinophils, red blood cells and chitin in arthropods and other invertebrates, also stains spores of Pseudoloma neurophilia. We compared this stain to the Gram, Fite’s acid fast, Giemsa, and H&E stains on eight aquatic microsporidian organisms that were readily available in our two laboratories: Loma salmonae, Glugea anomala, Pseudoloma neurophilia, Pleistophora hyphessobryconis, Pleistophora vermiformis, Glugea sp., Steinhausia mytilovum and an unidentified microsporidian from E. sinensis, UK. Based on tinctorial properties and background staining, the Luna stain performed better for detection of 6 of the 8 microsporidia. Gram stain was superior for the two microsporidia from invertebrates, Steinhausia mytilovum and the unidentified microsporidian from E. sinensis. PMID:21848126

  5. Coregulation of Soybean Vegetative Storage Protein Gene Expression by Methyl Jasmonate and Soluble Sugars 1

    Science.gov (United States)

    Mason, Hugh S.; DeWald, Daryll B.; Creelman, Robert A.; Mullet, John E.

    1992-01-01

    The soybean vegetative storage protein genes vspA and vspB are highly expressed in developing leaves, stems, flowers, and pods as compared with roots, seeds, and mature leaves and stems. In this paper, we report that physiological levels of methyl jasmonate (MeJA) and soluble sugars synergistically stimulate accumulation of vsp mRNAs. Treatment of excised mature soybean (Glycine max Merr. cv Williams) leaves with 0.2 molar sucrose and 10 micromolar MeJA caused a large accumulation of vsp mRNAs, whereas little accumulation occurred when these compounds were supplied separately. In soybean cell suspension cultures, the synergistic effect of sucrose and MeJA on the accumulation of vspB mRNA was maximal at 58 millimolar sucrose and was observed with fructose or glucose substituted for sucrose. In dark-grown soybean seedlings, the highest levels of vsp mRNAs occurred in the hypocotyl hook, which also contained high levels of MeJA and soluble sugars. Lower levels of vsp mRNAs, MeJA, and soluble sugars were found in the cotyledons, roots, and nongrowing regions of the stem. Wounding of mature soybean leaves induced a large accumulation of vsp mRNAs when wounded plants were incubated in the light. Wounded plants kept in the dark or illuminated plants sprayed with dichlorophenyldimethylurea, an inhibitor of photosynthetic electron transport, showed a greatly reduced accumulation of vsp mRNAs. The time courses for the accumulation of vsp mRNAs induced by wounding or sucrose/MeJA treatment were similar. These results strongly suggest that vsp expression is coregulated by endogenous levels of MeJA (or jasmonic acid) and soluble carbohydrate during normal vegetative development and in wounded leaves. ImagesFigure 1Figure 4Figure 5 PMID:16668757

  6. pH-metric solubility. 2: correlation between the acid-base titration and the saturation shake-flask solubility-pH methods.

    Science.gov (United States)

    Avdeef, A; Berger, C M; Brownell, C

    2000-01-01

    The objective of this study was to compare the results of a normal saturation shake-flask method to a new potentiometric acid-base titration method for determining the intrinsic solubility and the solubility-pH profiles of ionizable molecules, and to report the solubility constants determined by the latter technique. The solubility-pH profiles of twelve generic drugs (atenolol, diclofenac.Na, famotidine, flurbiprofen, furosemide, hydrochlorothiazide, ibuprofen, ketoprofen, labetolol.HCl, naproxen, phenytoin, and propranolol.HCl), with solubilities spanning over six orders of magnitude, were determined both by the new pH-metric method and by a traditional approach (24 hr shaking of saturated solutions, followed by filtration, then HPLC assaying with UV detection). The 212 separate saturation shake-flask solubility measurements and those derived from 65 potentiometric titrations agreed well. The analysis produced the correlation equation: log(1/S)titration = -0.063(+/- 0.032) + 1.025(+/- 0.011) log(1/S)shake-flask, s = 0.20, r2 = 0.978. The potentiometrically-derived intrinsic solubilities of the drugs were: atenolol 13.5 mg/mL, diclofenac.Na 0.82 microg/mL, famotidine 1.1 mg/ mL, flurbiprofen 10.6 microg/mL, furosemide 5.9 microg/mL, hydrochlorothiazide 0.70 mg/mL, ibuprofen 49 microg/mL, ketoprofen 118 microg/mL, labetolol.HCl 128 microg/mL, naproxen 14 microg/mL, phenytoin 19 microg/mL, and propranolol.HCl 70 microg/mL. The new potentiometric method was shown to be reliable for determining the solubility-pH profiles of uncharged ionizable drug substances. Its speed compared to conventional equilibrium measurements, its sound theoretical basis, its ability to generate the full solubility-pH profile from a single titration, and its dynamic range (currently estimated to be seven orders of magnitude) make the new pH-metric method an attractive addition to traditional approaches used by preformulation and development scientists. It may be useful even to discovery

  7. Study of protein-probe complexation equilibria and protein-surfactant interaction using charge transfer fluorescence probe methyl ester of N,N-dimethylamino naphthyl acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Mahanta, Subrata; Balia Singh, Rupashree; Bagchi, Arnab [Department of Chemistry University of Calcutta 92, A.P.C. Road, Kolkata 700009 (India); Nath, Debnarayan [Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Guchhait, Nikhil, E-mail: nguchhait@yahoo.co [Department of Chemistry University of Calcutta 92, A.P.C. Road, Kolkata 700009 (India)

    2010-06-15

    In this paper, we demonstrate the interaction between intramolecular charge transfer (ICT) probe-Methyl ester of N,N-dimethylamino naphthyl acrylic acid (MDMANA) with bovine serum albumin (BSA) using absorption and fluorescence emission spectroscopy. The nature of probe protein binding interaction, fluorescence resonance energy transfer from protein to probe and time resolved fluorescence decay measurement predict that the probe molecule binds strongly to the hydrophobic cavity of the protein. Furthermore, the interaction of the anionic surfactant sodium dodecyl sulphate (SDS) with water soluble protein BSA has been investigated using MDMANA as fluorescenece probe. The changes in the spectral characteristics of charge transfer fluorescence probe MDMANA in BSA-SDS environment reflects well the nature of the protein-surfactant binding interaction such as specific binding, non-cooperative binding, cooperative binding and saturation binding.

  8. Handling technique of spore-forming bacteria in radiation sterilization. 2. Determination of numbers and radiation resistance of spores

    International Nuclear Information System (INIS)

    Koshikawa, Tomihiko

    1994-01-01

    Stepwise ten-fold dilution of bacterial solution is required in the determination of bacterial spores. For this, the selection of diluted solution is important according to the purpose of experiment. First, the preparation of suspension of bacterial spores and selection of diluted solution are presented. Then, a method for determining the number of bacterial spores in materials is outlined in terms of dilution methods of bacterial solution (shaking and homogenization) and application method of diluted solution to the plating medium. Finally, a method for determining radiation resistance of spore-forming bacteria is explained according to the measurement conditions (suspension of bacterial spores and filters applied with bacterial spores). (N.K.)

  9. Handling technique of spore-forming bacteria in radiation sterilization. 2. Determination of numbers and radiation resistance of spores

    Energy Technology Data Exchange (ETDEWEB)

    Koshikawa, Tomihiko [Japan Radioisotope Association, Shiga (Japan). Koka Laboratory

    1994-12-01

    Stepwise ten-fold dilution of bacterial solution is required in the determination of bacterial spores. For this, the selection of diluted solution is important according to the purpose of experiment. First, the preparation of suspension of bacterial spores and selection of diluted solution are presented. Then, a method for determining the number of bacterial spores in materials is outlined in terms of dilution methods of bacterial solution (shaking and homogenization) and application method of diluted solution to the plating medium. Finally, a method for determining radiation resistance of spore-forming bacteria is explained according to the measurement conditions (suspension of bacterial spores and filters applied with bacterial spores). (N.K.).

  10. Effect of gamma irradiation on the protein, amino acids and carbohydrate contents of soya-gari diet

    International Nuclear Information System (INIS)

    Ogbadu, G.H.

    1979-01-01

    Soya-gari diet, prepared by enrichment of gari (Manihot esculanta Cranz) with soya flour, methionine, lysine and salt mixture was irradiated with doses of 62.5, 125, 250 and 500 Krad from a Co 60 γ irradiator. Gamma irradiation of the soya-gari diet with doses as high as 500 Krad had no significant effect on the amino acids, total proteins, soluble carbohydrates, hemicelluloses, cellulose and lignin contents. (author)

  11. A soluble fatty acyl-acyl carrier protein synthetase from the bioluminescent bacterium Vibrio harveyi.

    Science.gov (United States)

    Byers, D M; Holmes, C G

    1990-01-01

    An enzyme catalyzing the ligation of long chain fatty acids to bacterial acyl carrier protein (ACP) has been detected and partially characterized in cell extracts of the bioluminescent bacterium Vibrio harveyi. Acyl-ACP synthetase activity (optimal pH 7.5-8.0) required millimolar concentrations of ATP and Mg2+ and was slightly activated by Ca2+, but was inhibited at high ionic strength and by Triton X-100. ACP from either Escherichia coli (apparent Km = 20 microM) or V. harveyi was used as a substrate. Of the [14C]fatty acids tested as substrates (8-18 carbons), a preference for fatty acids less than or equal to 14 carbons in length was observed. Vibrio harveyi acyl-ACP synthetase appears to be a soluble hydrophilic enzyme on the basis of subcellular fractionation and Triton X-114 phase partition assay. The enzyme was not coinduced with luciferase activity or light emission in vivo during the late exponential growth phase in liquid culture. Acyl-ACP synthetase activity was also detected in extracts from the luminescent bacterium Vibrio fischeri, but not Photobacterium phosphoreum. The cytosolic nature and enzymatic properties of V. harveyi acyl-ACP synthetase indicate that it may have a different physiological role than the membrane-bound activity of E. coli, which has been implicated in phosphatidylethanolamine turnover. Acyl-ACP synthetase activity in V. harveyi could be involved in the intracellular activation and elongation of exogenous fatty acids that occurs in this species or in the reactivation of free myristic acid generated by luciferase.

  12. Transport of soluble proteins through the Golgi occurs by diffusion via continuities across cisternae

    Science.gov (United States)

    Beznoussenko, Galina V; Parashuraman, Seetharaman; Rizzo, Riccardo; Polishchuk, Roman; Martella, Oliviano; Di Giandomenico, Daniele; Fusella, Aurora; Spaar, Alexander; Sallese, Michele; Capestrano, Maria Grazia; Pavelka, Margit; Vos, Matthijn R; Rikers, Yuri GM; Helms, Volkhard; Mironov, Alexandre A; Luini, Alberto

    2014-01-01

    The mechanism of transport through the Golgi complex is not completely understood, insofar as no single transport mechanism appears to account for all of the observations. Here, we compare the transport of soluble secretory proteins (albumin and α1-antitrypsin) with that of supramolecular cargoes (e.g., procollagen) that are proposed to traverse the Golgi by compartment progression–maturation. We show that these soluble proteins traverse the Golgi much faster than procollagen while moving through the same stack. Moreover, we present kinetic and morphological observations that indicate that albumin transport occurs by diffusion via intercisternal continuities. These data provide evidence for a transport mechanism that applies to a major class of secretory proteins and indicate the co-existence of multiple intra-Golgi trafficking modes. DOI: http://dx.doi.org/10.7554/eLife.02009.001 PMID:24867214

  13. Impact of Serine/Threonine Protein Kinases on the Regulation of Sporulation in Bacillus subtilis.

    Science.gov (United States)

    Pompeo, Frédérique; Foulquier, Elodie; Galinier, Anne

    2016-01-01

    Bacteria possess many kinases that catalyze phosphorylation of proteins on diverse amino acids including arginine, cysteine, histidine, aspartate, serine, threonine, and tyrosine. These protein kinases regulate different physiological processes in response to environmental modifications. For example, in response to nutritional stresses, the Gram-positive bacterium Bacillus subtilis can differentiate into an endospore; the initiation of sporulation is controlled by the master regulator Spo0A, which is activated by phosphorylation. Spo0A phosphorylation is carried out by a multi-component phosphorelay system. These phosphorylation events on histidine and aspartate residues are labile, highly dynamic and permit a temporal control of the sporulation initiation decision. More recently, another kind of phosphorylation, more stable yet still dynamic, on serine or threonine residues, was proposed to play a role in spore maintenance and spore revival. Kinases that perform these phosphorylation events mainly belong to the Hanks family and could regulate spore dormancy and spore germination. The aim of this mini review is to focus on the regulation of sporulation in B. subtilis by these serine and threonine phosphorylation events and the kinases catalyzing them.

  14. Gold nanoparticles having dipicolinic acid imprinted nanoshell for Bacillus cereus spores recognition

    International Nuclear Information System (INIS)

    Gueltekin, Aytac; Ersoez, Arzu; Huer, Deniz; Sarioezlue, Nalan Yilmaz; Denizli, Adil; Say, Ridvan

    2009-01-01

    Taking into account the recognition element for sensors linked to molecular imprinted polymers (MIPs), a proliferation of interest has been witnessed by those who are interested in this subject. Indeed, MIP nanoparticles are theme which recently has come to light in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamidocysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer. Furthermore, a surface shell by synthetic host polymers based on molecular imprinting method for recognition has been reconstructed. In this method, methacryloyl iminodiacetic acid-chrome (MAIDA-Cr(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is the main participant of Bacillus cereus spores has been used as a template. Nanoshell sensors with templates produce a cavity that is selective for DPA. The DPA can simultaneously chelate to Cr(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Cr(III) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The interactions between DPA and MIP particles were studied observing fluorescence measurements. DPA addition caused significant decreases in fluorescence intensity because they induced photoluminescence emission from Au nanoparticles through the specific binding to the recognition sites of the crosslinked nanoshell polymer matrix. The binding affinity of the DPA imprinted nanoparticles has been explored by using the Langmuir and Scatchard methods and the analysis of the quenching results has been performed in terms of the Stern-Volmer equation.

  15. Stability constants and solubility of neptunium and plutonium complexes with alkylphosphoric acids in TBP

    International Nuclear Information System (INIS)

    Fedoseev, D.A.; Romanovskaya, I.A.; Artemova, L.A.; Gubina, M.Yu.

    1988-01-01

    Stability concetration constants K and solubility of neptunium and plutonium complexes with di- and monobuthylphosphoric acids (APC) and with orthophosphoric and di-2-ethylhexyl-phosphoric acids in 30% TBP solution-n-dodecane system are determined by spectrophotometric titration and radiometry methods. Posibility of forecasting radiation-chemical behaviour of actinids according to data on K and APC radiation-chemical yield values is demonstrated

  16. Solubility-pH profiles of some acidic, basic and amphoteric drugs.

    Science.gov (United States)

    Shoghi, Elham; Fuguet, Elisabet; Bosch, Elisabeth; Ràfols, Clara

    2013-01-23

    The solubility vs. pH profiles of five ionizable drugs of different nature (a monoprotic acid, a monoprotic base, a diprotic base and two amphoteric compounds showing a zwitterionic species each one) have been determined through two different methodologies: the classical shake-flask (S-F) and the potentiometric Cheqsol methods using in both instances the appropriate Henderson-Hasselbalch (H-H) or derived relationships. The results obtained independently from both approaches are consistent. A critical revision about the influence of the electrolyte used as buffering agent in the S-F method on the obtained solubility values is also performed. Thus, some deviations of the experimental points with respect the H-H profiles can be attributed to specific interactions between the buffering electrolyte and the drug due to the hydrotrophic character of citric and lactic acids. In other cases, the observed deviations are independent of the buffers used since they are caused by the formation of new species such as drug aggregates (cefadroxil) or the precipitation of a salt from a cationic species of the analyzed compound (quetiapine). Copyright © 2012 Elsevier B.V. All rights reserved.

  17. The effects of hydroxy fatty acids on the hyphal branching of germinated spores of AM fungi.

    Science.gov (United States)

    Nagahashi, Gerald; Douds, David D

    2011-01-01

    Two hydroxy fatty acids, tentatively identified previously in carrot root exudates, were tested for their effects on hyphal growth of the arbuscular mycorrhizal (AM) fungus, Gigaspora gigantea (Nicol. and Gerd.) Gerdemann and Trappe. Best results were achieved with a long-term bioassay (7-8d) with nanomolar concentrations throughout the Petri dish in contrast to the rapid microinjection bioassay (16-24h) in which nanogram quantities were injected near growing hyphal tips. When 5nM 2-hydroxy fatty acids of various chain length were tested, the length of the hydroxyl fatty acid was significant since only 2-hydroxytetradecanoic acid (2OH-TDA) and to a slightly lesser degree, 2-hydroxydodecanoic acid (2OH-DDA) induced a hyphal growth response while 2-hydroxydecanoic acid (2OH-DA) and 2-hydroxyhexadecanoic (2OH-HDA) acid did not. The position of the hydroxyl group was critical since 5nM 3-hydroxytetradecanoic acid (3OH-TDA) had no effect on hyphal growth. The length of the non-hydroxy containing straight chain fatty acid, per se, did not appear significant since none of these fatty acids had an effect on hyphal growth. The morphological growth response promoted by 2OH-TDA consisted of multiple lateral branches, spaced fairly regularly apart, along the primary germ tubes as well as some lateral branch formation off the major secondary hyphae. This growth response was identical to that observed when germinated spores were allowed to grow towards cultured carrot roots in vitro. This response to 2OH-TDA also was observed with an unidentified Gigaspora species but no morphological response was observed with Glomus intraradices Schenck and Smith. The results indicate that 2-hydroxy fatty acids are another putative category of root exudate signals perceived by Gigaspora species, stimulating an increase in elongated lateral branches. Published by Elsevier Ltd.

  18. Nitrogen-corrected True Metabolizable Energy and Amino Acid Digestibility of Chinese Corn Distillers Dried Grains with Solubles in Adult Cecectomized Roosters

    Directory of Open Access Journals (Sweden)

    F. Li

    2013-06-01

    Full Text Available This study was conducted to evaluate chemical composition, nitrogen-corrected true metabolizable energy (TMEn and true amino acids digestibility of corn distillers dried grains with solubles (DDGS produced in China. Twenty five sources of corn DDGS was collected from 8 provinces of China. A precision-fed rooster assay was used to determine TMEn and amino acids digestibility with 35 adult cecectomized roosters, in which each DDGS sample was tube fed (30 g. The average content of ash, crude protein, total amino acid, ether extract, crude fiber and neutral detergent fiber were 4.81, 27.91, 22.51, 15.22, 6.35 and 37.58%, respectively. TMEn of DDGS ranged from 1,779 to 3,071 kcal/kg and averaged 2,517 kcal/kg. Coefficient of variation for non-amino acid crude protein, ether extract, crude fiber and TMEn were 55.0, 15.7, 15.9 and 17.1%, respectively. The average true amino acid digestibility was 77.32%. Stepwise regression analysis obtained the following equation: TMEn, kcal/kg = −2,995.6+0.88×gross energy+49.63×a* (BIC = 248.8; RMSE = 190.8; p0.05. These results suggest that corn DDGS produced in China has a large variation in chemical composition, and gross energy and a* value can be used to generate TMEn predict equation.

  19. High-throughput method for optimum solubility screening for homogeneity and crystallization of proteins

    Science.gov (United States)

    Kim, Sung-Hou [Moraga, CA; Kim, Rosalind [Moraga, CA; Jancarik, Jamila [Walnut Creek, CA

    2012-01-31

    An optimum solubility screen in which a panel of buffers and many additives are provided in order to obtain the most homogeneous and monodisperse protein condition for protein crystallization. The present methods are useful for proteins that aggregate and cannot be concentrated prior to setting up crystallization screens. A high-throughput method using the hanging-drop method and vapor diffusion equilibrium and a panel of twenty-four buffers is further provided. Using the present methods, 14 poorly behaving proteins have been screened, resulting in 11 of the proteins having highly improved dynamic light scattering results allowing concentration of the proteins, and 9 were crystallized.

  20. Amino acids as co-amorphous stabilizers for poorly water soluble drugs--Part 1

    DEFF Research Database (Denmark)

    Löbmann, Korbinian; Grohganz, Holger; Laitinen, Riikka

    2013-01-01

    molecular weight excipients that form specific molecular interactions with the drug resulting in co-amorphous forms. The two poorly water soluble drugs carbamazepine and indomethacin were combined with amino acids from the binding sites of the biological receptors of these drugs. Mixtures of drug...

  1. In meso in situ serial X-ray crystallography of soluble and membrane proteins

    International Nuclear Information System (INIS)

    Huang, Chia-Ying; Olieric, Vincent; Ma, Pikyee; Panepucci, Ezequiel; Diederichs, Kay; Wang, Meitian; Caffrey, Martin

    2015-01-01

    A method for performing high-throughput in situ serial X-ray crystallography with soluble and membrane proteins in the lipid cubic phase is described. It works with microgram quantities of protein and lipid (and ligand when present) and is compatible with the most demanding sulfur SAD phasing. The lipid cubic phase (LCP) continues to grow in popularity as a medium in which to generate crystals of membrane (and soluble) proteins for high-resolution X-ray crystallographic structure determination. To date, the PDB includes 227 records attributed to the LCP or in meso method. Among the listings are some of the highest profile membrane proteins, including the β 2 -adrenoreceptor–G s protein complex that figured in the award of the 2012 Nobel Prize in Chemistry to Lefkowitz and Kobilka. The most successful in meso protocol to date uses glass sandwich crystallization plates. Despite their many advantages, glass plates are challenging to harvest crystals from. However, performing in situ X-ray diffraction measurements with these plates is not practical. Here, an alternative approach is described that provides many of the advantages of glass plates and is compatible with high-throughput in situ measurements. The novel in meso in situ serial crystallography (IMISX) method introduced here has been demonstrated with AlgE and PepT (alginate and peptide transporters, respectively) as model integral membrane proteins and with lysozyme as a test soluble protein. Structures were solved by molecular replacement and by experimental phasing using bromine SAD and native sulfur SAD methods to resolutions ranging from 1.8 to 2.8 Å using single-digit microgram quantities of protein. That sulfur SAD phasing worked is testament to the exceptional quality of the IMISX diffraction data. The IMISX method is compatible with readily available, inexpensive materials and equipment, is simple to implement and is compatible with high-throughput in situ serial data collection at macromolecular

  2. Effect of Difference in Fatty Acid Chain Lengths of Medium- Chain Lipids on Lipid/Surfactant/Water Phase Diagrams and Drug Solubility

    Directory of Open Access Journals (Sweden)

    Hetal N. Prajapati

    2011-09-01

    Full Text Available Lipids consisting of medium chain fatty acids are commonly used in the development of lipid-based selfemulsifying and self-microemulsifying drug delivery systems. However, no systematic approach to selecting one lipid over another has been reported in the literature. In this study, propylene glycol (PG monoester (PG monocaprylate, Capmul PG-8® and PG diester (PG dicaprylocaprate, Captex 200P® of C8-fatty acids were compared with PG monoester (PG monolaurate, Capmul PG-12® and PG diester (PG dilaurate, Capmul PG-2L® of C12-fatty acids with respect to their phase diagrams, and especially for their ability to form microemulsions in the presence of a common surfactant, Cremophor EL®, and water. The solubility of two model drugs, danazol and probucol, in the lipids and lipid/surfactant mixtures were also compared. The effect of the chain length of medium-chain fatty acids (C8 versus C12 on the phase diagrams of the lipids was minimal. Both shorter and longer chain lipids formed essentially similar microemulsion and emulsion regions in the presence of Cremophor EL® and water, although the C12-fatty acid esters formed larger gel regions in the phase diagrams than the C8-fatty acid esters. When monoesters were mixed with their respective diesters at 1:1 ratios, larger microemulsion regions with lower lipid particle sizes were observed compared to those obtained with individual lipids alone. While the solubility of both danazol and probucol increased greatly in all lipids studied, compared to their aqueous solubility, the solubility in C12-fatty acid esters was found to be lower than in C8-fatty acid esters when the lipids were used alone. This difference in solubility due to the difference in fatty acid chain length, practically disappeared when the lipids were combined with the surfactant.

  3. Effects of Toasting Time on Digestive Hydrolysis of Soluble and Insoluble 00-Rapeseed Meal Proteins

    NARCIS (Netherlands)

    Salazar-Villanea, Sergio; Bruininx, Erik M.A.M.; Gruppen, Harry; Carré, Patrick; Quinsac, Alain; Poel, van der Thomas

    2017-01-01

    Thermal damage to proteins can reduce their nutritional value. The effects of toasting time on the kinetics of hydrolysis, the resulting molecular weight distribution of 00-rapeseed meal (RSM) and the soluble and insoluble protein fractions separated from the RSM were studied. Hydrolysis was

  4. An amino acid depleted cell-free protein synthesis system for the incorporation of non-canonical amino acid analogs into proteins.

    Science.gov (United States)

    Singh-Blom, Amrita; Hughes, Randall A; Ellington, Andrew D

    2014-05-20

    Residue-specific incorporation of non-canonical amino acids into proteins is usually performed in vivo using amino acid auxotrophic strains and replacing the natural amino acid with an unnatural amino acid analog. Herein, we present an efficient amino acid depleted cell-free protein synthesis system that can be used to study residue-specific replacement of a natural amino acid by an unnatural amino acid analog. This system combines a simple methodology and high protein expression titers with a high-efficiency analog substitution into a target protein. To demonstrate the productivity and efficacy of a cell-free synthesis system for residue-specific incorporation of unnatural amino acids in vitro, we use this system to show that 5-fluorotryptophan and 6-fluorotryptophan substituted streptavidin retain the ability to bind biotin despite protein-wide replacement of a natural amino acid for the amino acid analog. We envisage this amino acid depleted cell-free synthesis system being an economical and convenient format for the high-throughput screening of a myriad of amino acid analogs with a variety of protein targets for the study and functional characterization of proteins substituted with unnatural amino acids when compared to the currently employed in vivo methodologies. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Production of N-acetyl-D-neuraminic acid using two sequential enzymes overexpressed as double-tagged fusion proteins

    Directory of Open Access Journals (Sweden)

    Cheng Chung-Hsien

    2009-07-01

    Full Text Available Abstract Background Two sequential enzymes in the production of sialic acids, N-acetyl-D-glucosamine 2-epimerase (GlcNAc 2-epimerase and N-acetyl-D-neuraminic acid aldolase (Neu5Ac aldolase, were overexpressed as double-tagged gene fusions. Both were tagged with glutathione S-transferase (GST at the N-terminus, but at the C-terminus, one was tagged with five contiguous aspartate residues (5D, and the other with five contiguous arginine residues (5R. Results Both fusion proteins were overexpressed in Escherichia coli and retained enzymatic activity. The fusions were designed so their surfaces were charged under enzyme reaction conditions, which allowed isolation and immobilization in a single step, through a simple capture with either an anionic or a cationic exchanger (Sepharose Q or Sepharose SP that electrostatically bound the 5D or 5R tag. The introduction of double tags only marginally altered the affinity of the enzymes for their substrates, and the double-tagged proteins were enzymatically active in both soluble and immobilized forms. Combined use of the fusion proteins led to the production of N-acetyl-D-neuraminic acid (Neu5Ac from N-acetyl-D-glucosamine (GlcNAc. Conclusion Double-tagged gene fusions were overexpressed to yield two enzymes that perform sequential steps in sialic acid synthesis. The proteins were easily immobilized via ionic tags onto ionic exchange resins and could thus be purified by direct capture from crude protein extracts. The immobilized, double-tagged proteins were effective for one-pot enzymatic production of sialic acid.

  6. Rapid Determination of Protein Solubility and Stability Conditions for NMR Studies Using Incomplete Factorial Design

    International Nuclear Information System (INIS)

    Ducat, Thierry; Declerck, Nathalie; Gostan, Thierry; Kochoyan, Michel; Demene, Helene

    2006-01-01

    Sample preparation constitutes a crucial and limiting step in structural studies of proteins by NMR. The determination of the solubility and stability (SAS) conditions of biomolecules at millimolar concentrations stays today empirical and hence time- and material-consuming. Only few studies have been recently done in this field and they have highlighted the interest of using crystallogenesis tools to optimise sample conditions. In this study, we have adapted a method based on incomplete factorial design and making use of crystallisation plates to quantify the influence of physico-chemical parameters such as buffer pH and salts on protein SAS. A description of the experimental set up and an evaluation of the method are given by case studies on two functional domains from the bacterial regulatory protein LicT as well as two other proteins. Using this method, we could rapidly determine optimised conditions for extracting soluble proteins from bacterial cells and for preparing purified protein samples sufficiently concentrated and stable for NMR characterisation. The drastic reduction in the time and number of experiments required for searching protein SAS conditions makes this method particularly well-adapted for a systematic investigation on a large range of physico-chemical parameters

  7. β-1,6-glucan synthesis-associated genes are required for proper spore wall formation in Saccharomyces cerevisiae.

    Science.gov (United States)

    Pan, Hua-Ping; Wang, Ning; Tachikawa, Hiroyuki; Nakanishi, Hideki; Gao, Xiao-Dong

    2017-11-01

    The yeast spore wall is an excellent model to study the assembly of an extracellular macromolecule structure. In the present study, mutants defective in β-1,6-glucan synthesis, including kre1∆, kre6∆, kre9∆ and big1∆, were sporulated to analyse the effect of β-1,6-glucan defects on the spore wall. Except for kre6∆, these mutant spores were sensitive to treatment with ether, suggesting that the mutations perturb the integrity of the spore wall. Morphologically, the mutant spores were indistinguishable from wild-type spores. They lacked significant sporulation defects partly because the chitosan layer, which covers the glucan layer, compensated for the damage. The proof for this model was obtained from the effect of the additional deletion of CHS3 that resulted in the absence of the chitosan layer. Among the double mutants, the most severe spore wall deficiency was observed in big1∆ spores. The majority of the big1∆chs3∆ mutants failed to form visible spores at a higher temperature. Given that the big1∆ mutation caused a failure to attach a GPI-anchored reporter, Cwp2-GFP, to the spore wall, β-1,6-glucan is involved in tethering of GPI-anchored proteins in the spore wall as well as in the vegetative cell wall. Thus, β-1,6-glucan is required for proper organization of the spore wall. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. The dynamics of acid-soluble phosphorus compounds in the course of winter and spring wheat germination under various thermic conditions. Part II. Labile phosphorus after hydrolysis of the acid-soluble fraction

    Directory of Open Access Journals (Sweden)

    A. Barbaro

    2015-06-01

    Full Text Available The changes in labile phosphorus compounds content during germination of wheat were investigated. These compounds were determined in acid-soluble germ extracts separated into fractions according to the solubility of their barium salts. Low germination temperature was found to raise the labile phosphorus content in the fraction of insoluble barium salts. If we assume that labile P of this fraction consisted mainly of adenosinedi- and triphosphates, it would seem that the rise, in the ATP and ADP level under the influence of low temperature may be essential for initiating flowering in winter varieties.

  9. Effectiveness of anchovy substrate application on decreasing acid solubility of Sprague Dawley rats’ tooth enamel (in vivo)

    Science.gov (United States)

    Triputra, F.; Puspitawati, R.; Gunawan, H. A.

    2017-08-01

    Anchovies (Stolephorus insularis), a natural resource of Indonesia, contain fluoride in the form of CaF2 and can function as a fluoridation material to prevent dental caries. The aim of this study is to study the effectiveness of anchovy substrate, through food or topical application, in decreasing the acid solubility of tooth enamel. This research used 14 Sprague Dawley rats as subjects divided into the following 5 groups: baseline, experimental feeding, experimental smearing, and their negative controls. After 15 days of anchovy substrate application, lower incisors were extracted and the acid solubility of enamel was analyzed qualitatively and quantitatively using a stereo microscope and a Micro-Vickers Hardness Tester. Analysis of enamel surface destruction and enamel surface microscopic hardness shifting after a 60 sec application of H2PO4 (50% concentration) resulted in a decrease in acid solubility of enamel treated with anchovy substrate. This result can be seen with both the chewing and smearing method. S. insularis can be used as an alternative material for fluoridation.

  10. In vitro mutagenesis of commercial fern, Asplenium nidus from spores

    International Nuclear Information System (INIS)

    Norazlina Noordin

    2004-01-01

    Asplenium is a largest, most diverse fern genera. One of the common species is Asplenium nidus, well known as Bird's-nest fern, a medium to large fern with erect, stout, unbranched rhizomes. In creating variability of ferns for the benefit of the ornamental plant industry, in vitro mutagenesis is used. In this study, spores of Asplenium nidus were collected from frond bearing mature sporangia. Spores were cultured in modified 1/2 MS basal medium supplemented with various combinations of 6-Benzylaminopurine (BAP) and Naphtalene Acetic Acid (NAA). Spore cultures were incubated in incubation room at 24 degree C with 16 hours photoperiod (3500 lux). It was found that, the most effective combinations were 1 mg/1 BAP + 0. 1 mg/1 NAA and 2mg/1 BAP + 0. 1 mg/1 NAA. Prothallus was formed after 10 days of cultures and gametophytes were formed 1 month later. These gametophytes were irradiated with Gamma ray at doses of 0, 20, 90, 120, 150 and 180 Gy. From the preliminary result obtained from this study, for generating variations and desired phenotypic expression for Asplenium nidus, recommended doses for in vitro mutagenesis using spores are between 90 Gy to 150 Gy. Gametophytes were subcultured at monthly interval to ensure further development and propagation. Frequent monitoring for any changes in the morphology of the irradiated Asplenium nidus plants were carried out. (Author)

  11. Estimation of solubility of organo-phosphorus extractants by P determination using molybdovanadophosphoric acid method

    International Nuclear Information System (INIS)

    Gill, J.S.; Kotekar, M.K.; Singh, H.

    2005-01-01

    Solvent extraction processes have been found to be suitable for uranium recovery from phosphoric acid. Various extractants like di-2-ethyl hexylphosphoric acid (D2EHPA), di-nonylphenyl phosphoric acid (DNPPA) and synergistic agents like tri-butyl phosphate (TBP), tri-octyl phosphine oxide (TOPO) have been used in liquid-liquid extraction of uranium from phosphoric acid. Contents of these organo-phosphorus compounds in aqueous raffinates need estimation for process requirements. Solubility of Tri-butyl phosphate (TBP) and Di-2-ethylhexyl phosphoric acid (D2EHPA) extractants have been determined in different media of water, oxalic acid (0.6M) and sulphuric acid (3.75M) solutions. These compounds were estimated by determining their phosphorus (P) contents employing molybdovanadophosphoric acid method, after digesting and solubalizing them in nitric and perchloric acid. (author)

  12. Enthalpy-entropy compensation for the solubility of drugs in solvent mixtures: paracetamol, acetanilide, and nalidixic acid in dioxane-water.

    Science.gov (United States)

    Bustamante, P; Romero, S; Pena, A; Escalera, B; Reillo, A

    1998-12-01

    In earlier work, a nonlinear enthalpy-entropy compensation was observed for the solubility of phenacetin in dioxane-water mixtures. This effect had not been earlier reported for the solubility of drugs in solvent mixtures. To gain insight into the compensation effect, the behavior of the apparent thermodynamic magnitudes for the solubility of paracetamol, acetanilide, and nalidixic acid is studied in this work. The solubility of these drugs was measured at several temperatures in dioxane-water mixtures. DSC analysis was performed on the original powders and on the solid phases after equilibration with the solvent mixture. The thermal properties of the solid phases did not show significant changes. The three drugs display a solubility maximum against the cosolvent ratio. The solubility peaks of acetanilide and nalidixic acid shift to a more polar region at the higher temperatures. Nonlinear van't Hoff plots were observed for nalidixic acid whereas acetanilide and paracetamol show linear behavior at the temperature range studied. The apparent enthalpies of solution are endothermic going through a maximum at 50% dioxane. Two different mechanisms, entropy and enthalpy, are suggested to be the driving forces that increase the solubility of the three drugs. Solubility is entropy controlled at the water-rich region (0-50% dioxane) and enthalpy controlled at the dioxane-rich region (50-100% dioxane). The enthalpy-entropy compensation analysis also suggests that two different mechanisms, dependent on cosolvent ratio, are involved in the solubility enhancement of the three drugs. The plots of deltaH versus deltaG are nonlinear, and the slope changes from positive to negative above 50% dioxane. The compensation effect for the thermodynamic magnitudes of transfer from water to the aqueous mixtures can be described by a common empirical nonlinear relationship, with the exception of paracetamol, which follows a separate linear relationship at dioxane ratios above 50%. The

  13. Dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs with poor water solubility.

    Science.gov (United States)

    Tran, Phuong Ha-Lien; Tran, Thao Truong-Dinh; Lee, Kyoung-Ho; Kim, Dong-Jin; Lee, Beom-Jin

    2010-05-01

    Although the solid dispersion method has been known to increase the dissolution rate of poorly water-soluble drugs by dispersing them in hydrophilic carriers, one obstacle of the solid dispersion method is its limited solubilization capacity, especially for pH-dependent soluble drugs. pH-modified solid dispersion, in which pH modifiers are incorporated, may be a useful method for increasing the dissolution rate of weakly acidic or basic drugs. Sufficient research, including the most recent reports, was undertaken in this review. How could the inclusion of the pH the pH modifiers in the solid dispersion system change drug structural behaviors, molecular interactions, microenvironmental pH, and/or release rate of pH modifiers, relating with the enhanced dissolution of weakly acidic or weakly basic drugs with poor water solubility? These questions have been investigated to determine the dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs. It is believed that step-by-step mechanistic approaches could provide the ultimate solution for solubilizing several poorly water-soluble drugs with pH-dependent solubility from a solid dispersion system, as well as provide ideas for developing future dosage systems.

  14. Assembly and Function of a Spore Coat-Associated Transglutaminase of Bacillus subtilis

    Science.gov (United States)

    Zilhão, Rita; Isticato, Rachele; Martins, Lígia O.; Steil, Leif; Völker, Uwe; Ricca, Ezio; Moran, Charles P.; Henriques, Adriano O.

    2005-01-01

    The assembly of a multiprotein coat around the Bacillus subtilis spore confers resistance to lytic enzymes and noxious chemicals and ensures normal germination. Part of the coat is cross-linked and resistant to solubilization. The coat contains ɛ-(γ-glutamyl)lysyl cross-links, and the expression of the gene (tgl) for a spore-associated transglutaminase was shown before to be required for the cross-linking of coat protein GerQ. Here, we have investigated the assembly and function of Tgl. We found that Tgl associates, albeit at somewhat reduced levels, with the coats of mutants that are unable to assemble the outer coat (cotE), that are missing the inner coat and with a greatly altered outer coat (gerE), or that are lacking discernible inner and outer coat structures (cotE gerE double mutant). This suggests that Tgl is present at various levels within the coat lattice. The assembly of Tgl occurs independently of its own activity, as a single amino acid substitution of a cysteine to an alanine (C116A) at the active site of Tgl does not affect its accumulation or assembly. However, like a tgl insertional mutation, the tglC116A allele causes increased extractability of polypeptides of about 40, 28, and 16 kDa in addition to GerQ (20 kDa) and affects the structural integrity of the coat. We show that most Tgl is assembled onto the spore surface soon after its synthesis in the mother cell under σK control but that the complete insolubilization of at least two of the Tgl-controlled polypeptides occurs several hours later. We also show that a multicopy allele of tgl causes increased assembly of Tgl and affects the assembly, structure, and functional properties of the coat. PMID:16267299

  15. Imaging bacterial spores by soft-x-ray microscopy

    International Nuclear Information System (INIS)

    Stead, A.D.; Ford, T.W.; Judge, J.

    1997-01-01

    Bacterial spores are able to survive dehydration, but neither the physiological nor structural basis of this have been fully elucidated. Furthermore, once hydrated, spores often require activation before they will germinate. Several treatments can be used to activate spores, but in the case of Bacillus subtlis the most effective is heat treatment. The physiological mechanism associated with activation is also not understood, but some workers suggest that the loss of calcium from the spores may be critical. However, just prior to germination, the spores change from being phase bright to phase dark when viewed by light microscopy. Imaging spores by soft x-ray microscopy is possible without fixation. Thus, in contrast to electron microscopy, it is possible to compare the structure of dehydrated and hydrated spores in a manner not possible previously. A further advantage is that it is possible to monitor individual spores by phase contrast light microscopy immediately prior to imaging with soft x-rays; whereas, with both electron microscopy and biochemical studies, it is a population of spores being studied without knowledge of the phase characteristics of individual spores. This study has therefore tried to compare dehydrated and hydrated spores and to determine if there is a mass loss from individual spores as they pass the transition from being phase bright to phase dark

  16. Imaging bacterial spores by soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stead, A.D.; Ford, T.W. [Univ. of London, Surrey (United Kingdom); Judge, J. [Unilever plc, Sharnbrook (United Kingdom)] [and others

    1997-04-01

    Bacterial spores are able to survive dehydration, but neither the physiological nor structural basis of this have been fully elucidated. Furthermore, once hydrated, spores often require activation before they will germinate. Several treatments can be used to activate spores, but in the case of Bacillus subtlis the most effective is heat treatment. The physiological mechanism associated with activation is also not understood, but some workers suggest that the loss of calcium from the spores may be critical. However, just prior to germination, the spores change from being phase bright to phase dark when viewed by light microscopy. Imaging spores by soft x-ray microscopy is possible without fixation. Thus, in contrast to electron microscopy, it is possible to compare the structure of dehydrated and hydrated spores in a manner not possible previously. A further advantage is that it is possible to monitor individual spores by phase contrast light microscopy immediately prior to imaging with soft x-rays; whereas, with both electron microscopy and biochemical studies, it is a population of spores being studied without knowledge of the phase characteristics of individual spores. This study has therefore tried to compare dehydrated and hydrated spores and to determine if there is a mass loss from individual spores as they pass the transition from being phase bright to phase dark.

  17. Stability constants and solubility of neptunium and plutonium complexes with alkylphosphoric acids in TBP

    International Nuclear Information System (INIS)

    Fedoseev, D.A.; Romanovskaya, I.A.; Artemova, L.A.; Gibina, M.Yu.

    1989-01-01

    The concentration stability constants (K s ) and solubility of neptunium and plutonium complexes with di- and monobutylphosphoric acids (APA), as well as with orthophosphoric acid in the system composed of 30% TBP + n-dodecane, have been determined by spectrophotometric titration and radiometry. The feasibility of predicting the radiative chemical behavior of actinides based on their K s values and the radiative chemical yield of APA has been demonstrated

  18. Fungal spores as potential ice nuclei in fog/cloud water and snow

    Science.gov (United States)

    Bauer, Heidi; Goncalves, Fabio L. T.; Schueller, Elisabeth; Puxbaum, Hans

    2010-05-01

    INTRODUCTION: In discussions about climate change and precipitation frequency biological ice nucleation has become an issue. While bacterial ice nucleation (IN) is already well characterized and even utilized in industrial processes such as the production of artificial snow or to improve freezing processes in food industry, less is known about the IN potential of fungal spores which are also ubiquitous in the atmosphere. A recent study performed at a mountain top in the Rocky Mountains suggests that fungal spores and/or pollen might play a role in increased IN abundance during periods of cloud cover (Bowers et al. 2009). In the present work concentrations of fungal spores in fog/cloud water and snow were determined. EXPERIMENTAL: Fog samples were taken with an active fog sampler in 2008 in a traffic dominated area and in a national park in São Paulo, Brazil. The number concentrations of fungal spores were determined by microscopic by direct enumeration by epifluorescence microscopy after staining with SYBR Gold nucleic acid gel stain (Bauer et al. 2008). RESULTS: In the fog water collected in the polluted area at a junction of two highly frequented highways around 22,000 fungal spores mL-1 were counted. Fog in the national park contained 35,000 spores mL-1. These results were compared with cloud water and snow samples from Mt. Rax, situated at the eastern rim of the Austrian Alps. Clouds contained on average 5,900 fungal spores mL-1 cloud water (1,300 - 11,000) or 2,200 spores m-3 (304 - 5,000). In freshly fallen snow spore concentrations were lower than in cloud water, around 1,000 fungal spores mL-1 were counted (Bauer et al. 2002). In both sets of samples representatives of the ice nucleating genus Fusarium could be observed. REFERENCES: Bauer, H., Kasper-Giebl, A., Löflund, M., Giebl, H., Hitzenberger, R., Zibuschka, F., Puxbaum, H. (2002). The contribution of bacteria and fungal spores to the organic carbon content of cloud water, precipitation and aerosols

  19. Large-scale proteome analysis of abscisic acid and ABSCISIC ACID INSENSITIVE3-dependent proteins related to desiccation tolerance in Physcomitrella patens.

    Science.gov (United States)

    Yotsui, Izumi; Serada, Satoshi; Naka, Tetsuji; Saruhashi, Masashi; Taji, Teruaki; Hayashi, Takahisa; Quatrano, Ralph S; Sakata, Yoichi

    2016-03-18

    Desiccation tolerance is an ancestral feature of land plants and is still retained in non-vascular plants such as bryophytes and some vascular plants. However, except for seeds and spores, this trait is absent in vegetative tissues of vascular plants. Although many studies have focused on understanding the molecular basis underlying desiccation tolerance using transcriptome and proteome approaches, the critical molecular differences between desiccation tolerant plants and non-desiccation plants are still not clear. The moss Physcomitrella patens cannot survive rapid desiccation under laboratory conditions, but if cells of the protonemata are treated by the phytohormone abscisic acid (ABA) prior to desiccation, it can survive 24 h exposure to desiccation and regrow after rehydration. The desiccation tolerance induced by ABA (AiDT) is specific to this hormone, but also depends on a plant transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3). Here we report the comparative proteomic analysis of AiDT between wild type and ABI3 deleted mutant (Δabi3) of P. patens using iTRAQ (Isobaric Tags for Relative and Absolute Quantification). From a total of 1980 unique proteins that we identified, only 16 proteins are significantly altered in Δabi3 compared to wild type after desiccation following ABA treatment. Among this group, three of the four proteins that were severely affected in Δabi3 tissue were Arabidopsis orthologous genes, which were expressed in maturing seeds under the regulation of ABI3. These included a Group 1 late embryogenesis abundant (LEA) protein, a short-chain dehydrogenase, and a desiccation-related protein. Our results suggest that at least three of these proteins expressed in desiccation tolerant cells of both Arabidopsis and the moss are very likely to play important roles in acquisition of desiccation tolerance in land plants. Furthermore, our results suggest that the regulatory machinery of ABA- and ABI3-mediated gene expression for desiccation

  20. Solubilities of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid in water

    Energy Technology Data Exchange (ETDEWEB)

    Mishelevich, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel); Apelblat, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel)], E-mail: apelblat@bgu.ac.il

    2008-05-15

    The solubility in water of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid was determined in the 278.15 K to 343.15 K temperature range. The solubility of these compounds served to permit the evaluation of the apparent molar enthalpies of solution.

  1. Solubilities of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid in water

    International Nuclear Information System (INIS)

    Mishelevich, Alexander; Apelblat, Alexander

    2008-01-01

    The solubility in water of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid was determined in the 278.15 K to 343.15 K temperature range. The solubility of these compounds served to permit the evaluation of the apparent molar enthalpies of solution

  2. Protein biosynthesis in isolated human scalp hair follicles.

    Science.gov (United States)

    Vermorken, A J; Weterings, P J; Bloemendal, H

    1979-02-15

    The present study demonstrates that protein biosynthesis can be studied in single isolated human scalp hair follicles. The matrix and the sheath are the main regions where amino acids are built in. Incorporation is linear for at least five hours. The newly synthesized proteins can be separated into a water-soluble, a urea-soluble and a urea-insoluble fraction. Product analysis has been performed on the first two fractions, revealing different protein patterns.

  3. Survival of Spores of Trichoderma longibrachiatum in Space: data from the Space Experiment SPORES on EXPOSE-R

    Science.gov (United States)

    Neuberger, Katja; Lux-Endrich, Astrid; Panitz, Corinna

    2015-01-01

    In the space experiment `Spores in artificial meteorites' (SPORES), spores of the fungus Trichoderma longibrachiatum were exposed to low-Earth orbit for nearly 2 years on board the EXPOSE-R facility outside of the International Space Station. The environmental conditions tested in space were: space vacuum at 10-7-10-4 Pa or argon atmosphere at 105 Pa as inert gas atmosphere, solar extraterrestrial ultraviolet (UV) radiation at λ > 110 nm or λ > 200 nm with fluences up to 5.8 × 108 J m-2, cosmic radiation of a total dose range from 225 to 320 mGy, and temperature fluctuations from -25 to +50°C, applied isolated or in combination. Comparable control experiments were performed on ground. After retrieval, viability of spores was analysed by two methods: (i) ethidium bromide staining and (ii) test of germination capability. About 30% of the spores in vacuum survived the space travel, if shielded against insolation. However, in most cases no significant decrease was observed for spores exposed in addition to the full spectrum of solar UV irradiation. As the spores were exposed in clusters, the outer layers of spores may have shielded the inner part. The results give some information about the likelihood of lithopanspermia, the natural transfer of micro-organisms between planets. In addition to the parameters of outer space, sojourn time in space seems to be one of the limiting parameters.

  4. Hydrogen solubility measurements of analyzed tall oil fractions and a solubility model

    International Nuclear Information System (INIS)

    Uusi-Kyyny, Petri; Pakkanen, Minna; Linnekoski, Juha; Alopaeus, Ville

    2017-01-01

    Highlights: • Hydrogen solubility was measured in four tall oil fractions between 373 and 597 K. • Continuous flow synthetic isothermal and isobaric method was used. • A Henry’s law model was developed for the distilled tall oil fractions. • The complex composition of the samples was analyzed and is presented. - Abstract: Knowledge of hydrogen solubility in tall oil fractions is important for designing hydrotreatment processes of these complex nonedible biobased materials. Unfortunately measurements of hydrogen solubility into these fractions are missing in the literature. This work reports hydrogen solubility measured in four tall oil fractions between 373 and 597 K and at pressures from 5 to 10 MPa. Three of the fractions were distilled tall oil fractions their resin acids contents are respectively 2, 20 and 23 in mass-%. Additionally one fraction was a crude tall oil (CTO) sample containing sterols as the main neutral fraction. Measurements were performed using a continuous flow synthetic isothermal and isobaric method based on the visual observation of the bubble point. Composition of the flow was changed step-wise for the bubble point composition determination. We assume that the tall oil fractions did not react during measurements, based on the composition analysis performed before and after the measurements. Additionally the densities of the fractions were measured at atmospheric pressure from 293.15 to 323.15 K. A Henry’s law model was developed for the distilled tall oil fractions describing the solubility with an absolute average deviation of 2.1%. Inputs of the solubility model are temperature, total pressure and the density of the oil at 323.15 K. The solubility of hydrogen in the CTO sample can be described with the developed model with an absolute average deviation of 3.4%. The solubility of hydrogen increases both with increasing pressure and/or increasing temperature. The more dense fractions of the tall oil exhibit lower hydrogen

  5. Fluorescence-based methods for the detection of pressure-induced spore germination and inactivation

    Science.gov (United States)

    Baier, Daniel; Reineke, Kai; Doehner, Isabel; Mathys, Alexander; Knorr, Dietrich

    2011-03-01

    The application of high pressure (HP) provides an opportunity for the non-thermal preservation of high-quality foods, whereas highly resistant bacterial endospores play an important role. It is known that the germination of spores can be initiated by the application of HP. Moreover, the resistance properties of spores are highly dependent on their physiological states, which are passed through during the germination. To distinguish between different physiological states and to detect the amount of germinated spores after HP treatments, two fluorescence-based methods were applied. A flow cytometric method using a double staining with SYTO 16 as an indicator for germination and propidium iodide as an indicator for membrane damage was used to detect different physiological states of the spores. During the first step of germination, the spore-specific dipicolinic acid (DPA) is released [P. Setlow, Spore germination, Curr. Opin. Microbiol. 6 (2003), pp. 550-556]. DPA reacts with added terbium to form a distinctive fluorescent complex. After measuring the fluorescence intensity at 270 nm excitation wavelength in a fluorescence spectrophotometer, the amount of germinated spores can be determined. Spores of Bacillus subtilis were treated at pressures from 150 to 600 MPa and temperatures from 37 °C to 60 °C in 0.05 M ACES buffer solution (pH 7) for dwell times of up to 2 h. During the HP treatments, inactivation up to 2log 10 cycles and thermal sensitive populations up to 4log 10 cycles could be detected by plate counts. With an increasing number of thermal sensitive spores, an increased proportion of spores in germinated states was detected by flow cytometry. Also the released amount of DPA increased during the dwell times. Moreover, a clear pressure-temperature-time-dependency was shown by screening different conditions. The fluorescence-based measurement of the released DPA can provide the opportunity of an online monitoring of the germination of spores under HP inside

  6. Soluble expression of recomb inant cMyc, Klf4, Oct4, and Sox2 proteins in bacteria and transduction into living cells

    Directory of Open Access Journals (Sweden)

    Guo-Dan Liu

    2017-04-01

    Full Text Available AIM: To develop a new method to produce recombinant reprogramming proteins, cMyc, Klf4, Oct4, and Sox2, in soluble format with low cost for the generation of induced pluripotent stem cells (iPSCs. METHODS: A short polypeptide sequence derived from the HIV trans-activator of transcription protein (TAT and the nucleus localization signal (NLS polypeptide were fused to the N terminus of the reprogramming proteins and they were constructed into pCold-SUMO vector which can extremely improve the solubility of recombinant proteins. Then these vector plasmids were transformed into E. coli BL21 (DE3 Chaperone competent cells for amplification. The solubility of these recombinant proteins was determined by SDS-PAGE and Coomassie brilliant blue staining. The recombinant proteins were purified by Ni-NTA resin and identified by Western blot. The transduction of these proteins into HEK 293T cells were evaluated by immunofluorescence staining. RESULTS: These four reprogramming proteins could be produced in soluble format in pCold-SUMO expression vector system with the assistance of chaperone proteins in bacteria. The proteins were purified successfully with a purity of over 70% with a relative high transduction rate into 293 cells. CONCLUSION: The results in the present study indicate the four important reprogramming proteins, cMyc, Klf4, Oct4, and Sox2, can be produced in soluble format in bacteria with low cost. Our new method thus might be expected to greatly contribute to the future study of iPSCs.

  7. Incorporation of Mg and Ca into nanostructured Fe2O3 improves Fe solubility in dilute acid and sensory characteristics in foods.

    Science.gov (United States)

    Hilty, Florentine M; Knijnenburg, Jesper T N; Teleki, Alexandra; Krumeich, Frank; Hurrell, Richard F; Pratsinis, Sotiris E; Zimmermann, Michael B

    2011-01-01

    Iron deficiency is one of the most common micronutrient deficiencies worldwide. Food fortification can be an effective and sustainable strategy to reduce Fe deficiency but selection of iron fortificants remains a challenge. Water-soluble compounds, for example, FeSO(4), usually demonstrate high bioavailability but they often cause unacceptable sensory changes in foods. On the other hand, poorly acid-soluble Fe compounds, for example FePO(4), may cause fewer adverse sensory changes in foods but are usually not well bioavailable since they need to be dissolved in the stomach prior to absorption. The solubility and the bioavailability of poorly acid-soluble Fe compounds can be improved by decreasing their primary particle size and thereby increasing their specific surface area. Here, Fe oxide-based nanostructured compounds with added Mg or Ca were produced by scalable flame aerosol technology. The compounds were characterized by nitrogen adsorption, X-ray diffraction, transmission electron microscopy, and Fe solubility in dilute acid. Sensory properties of the Fe-based compounds were tested in 2 highly reactive, polyphenol-rich food matrices: chocolate milk and fruit yoghurt. The Fe solubility of nanostructured Fe(2)O(3) doped with Mg or Ca was higher than that of pure Fe(2)O(3). Since good solubility in dilute acid was obtained despite the inhomogeneity of the powders, inexpensive precursors, for example Fe- and Ca-nitrates, can be used for their manufacture. Adding Mg or Ca lightened powder color, while sensory changes when added to foods were less pronounced than for FeSO(4). The combination of high Fe solubility and low reactivity in foods makes these flame-made nanostructured compounds promising for food fortification. Practical Application: The nanostructured iron-containing compounds presented here may prove useful for iron fortification of certain foods; they are highly soluble in dilute acid and likely to be well absorbed in the gut but cause less severe

  8. Prediction of Starch, Soluble Sugars and Amino Acids in Potatoes (Solanum tuberosum L.) Using Hyperspectral Imaging, Dielectric and LF-NMR Methodologies

    DEFF Research Database (Denmark)

    Kjær, Anders; Nielsen, Glenn; Stærke, Søren

    2016-01-01

    Handling and processing of potatoes is performed in increasingly large and more automated facilities, and the industry calls for more automated machinery for quality assessment and sorting by concentration of starch, soluble sugars, protein, amino acids etc. of the potato tubers. The present study...... cultivars were simultaneously sampled for analyses of content and scanned by the five different scanning methods. The resulting multivariate dataset was used to estimate the prediction ability of the individual scanning methods on starch-related parameters, selected simple sugars, selected amino acids......, conductivity of pressed cell sap and cell sizes. Results showed that most types of spectral analyses had relatively high potential for predicting the starch-related parameters and medium potential for predicting the concentration of the reducing sugars fructose and glucose. Most methods showed medium potential...

  9. Exploring the interaction network of the Bacillus subtilis outer coat and crust proteins.

    Science.gov (United States)

    Krajčíková, Daniela; Forgáč, Vladimír; Szabo, Adam; Barák, Imrich

    2017-11-01

    Bacillus subtilis spores, representatives of an exceptionally resistant dormant cell type, are encircled by a thick proteinaceous layer called the spore coat. More than 80 proteins assemble into four distinct coat layers: a basement layer, an inner coat, an outer coat and a crust. As the spore develops inside the mother cell, spore coat proteins synthesized in the cytoplasm are gradually deposited onto the prespore surface. A small set of morphogenetic proteins necessary for spore coat morphogenesis are thought to form a scaffold to which the rest of the coat proteins are attached. Extensive localization and proteomic studies using wild type and mutant spores have revealed the arrangement of individual proteins within the spore coat layers. In this study we examined the interactions between the proteins localized to the outer coat and crust using a bacterial two hybrid system. These two layers are composed of at least 25 components. Self-interactions were observed for most proteins and numerous novel interactions were identified. The most interesting contacts are those made with the morphogenetic proteins CotE, CotY and CotZ; these could serve as a basis for understanding the specific roles of particular proteins in spore coat morphogenesis. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Thermodynamic approach to improving solubility prediction of co-crystals in comparison with individual poorly soluble components

    International Nuclear Information System (INIS)

    Perlovich, German L.

    2014-01-01

    Highlights: • Thermodynamic approach for solubility improvement of co-crystal was developed. • The graphical technique for estimation of co-crystal solubility was elaborated. • Hydration enthalpies of some drugs and amino acids were calculated. • Applicability/operability of the approach was exemplified by some drugs and amino acids. - Abstract: A novel thermodynamic approach to compare poorly soluble components (active pharmaceutical ingredient (API)) both in co-crystals and individual compounds was developed. An algorithm of choosing potential co-crystals with improved solubility characteristics on the basis of the known solvation/hydration API and co-former enthalpies is described. The applicability and operability of the algorithm were tested exemplified by some drugs and amino acids

  11. Protection of Bacillus pumilus Spores by Catalases

    OpenAIRE

    Checinska, Aleksandra; Burbank, Malcolm; Paszczynski, Andrzej J.

    2012-01-01

    Bacillus pumilus SAFR-032, isolated at spacecraft assembly facilities of the National Aeronautics and Space Administration Jet Propulsion Laboratory, is difficult to kill by the sterilization method of choice, which uses liquid or vapor hydrogen peroxide. We identified two manganese catalases, YjqC and BPUM_1305, in spore protein extracts of several B. pumilus strains by using PAGE and mass spectrometric analyses. While the BPUM_1305 catalase was present in six of the B. pumilus strains teste...

  12. Effect of Amino Acid Substitutions in the GerAA Protein on the Function of the Alanine-Responsive Germinant Receptor of Bacillus subtilis Spores▿

    Science.gov (United States)

    Mongkolthanaruk, Wiyada; Cooper, Gareth R.; Mawer, Julia S. P.; Allan, Raymond N.; Moir, Anne

    2011-01-01

    Spores of Bacillus subtilis require the GerAA, GerAB, and GerAC receptor proteins for l-alanine-induced germination. Mutations in gerAA, both random and site directed, result in phenotypes that identify amino acid residues important for receptor function in broad terms. They highlight the functional importance of two regions in the central, integral membrane domain of GerAA. A P324S substitution in the first residue of a conserved PFPP motif results in a 10-fold increase in a spore's sensitivity to alanine; a P326S change results in the release of phase-dark spores, in which the receptor may be in an “activated” or “quasigerminated” state. Substitutions in residues 398 to 400, in a short loop between the last two likely membrane-spanning helices of this central domain, all affect the germination response, with the G398S substitution causing a temperature-sensitive defect. In others, there are wider effects on the receptor: if alanine is substituted for conserved residue N146, H304, or E330, a severe defect in l-alanine germination results. This correlates with the absence of GerAC, suggesting that the assembly or stability of the entire receptor complex has been compromised by the defect in GerAA. In contrast, severely germination-defective mutants such as E129K, L373F, S400F, and M409N mutants retain GerAC at normal levels, suggesting more local and specific effects on the function of GerAA itself. Further interpretation will depend on progress in structural analysis of the receptor proteins. PMID:21378197

  13. Soluble scute proteins of healthy and ill desert tortoises (Gopherus agassizii)

    Science.gov (United States)

    Homer, B.L.; Li, C.; Berry, K.H.; Denslow, N.D.; Jacobson, E.R.; Sawyer, R.H.; Williams, J.E.

    2001-01-01

    Objectives - To characterize protein composition of shell scute of desert tortoises and to determine whether detectable differences could be used to identify healthy tortoises from tortoises with certain illnesses. Animals - 20 desert tortoises. Procedures - Complete postmortem examinations were performed on all tortoises. Plastron scute proteins were solubilized, scute proteins were separated by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and proteins were analyzed, using densitometry. Two-dimensional immobilized pH gradient-PAGE (2D IPG-PAGE) and immunoblot analysis, using polyclonal antisera to chicken-feather ?? keratin and to alligator-scale ?? keratin, were conducted on representative samples. The 14-kd proteins were analyzed for amino acid composition. Results - The SDS-PAGE and densitometry revealed 7 distinct bands, each with a mean relative protein concentration of > 1 %, ranging from 8 to 47 kd, and a major protein component of approximately 14 kd that constituted up to 75% of the scute protein. The 2D IPG-PAGE revealed additional distinct 62-and 68-kd protein bands. On immunoblot analysis, the 14-, 32-, and 45-kd proteins reacted with both antisera. The 14-kd proteins had an amino acid composition similar to that of chicken ?? keratins. There was a substantial difference in the percentage of the major 14-kd proteins from scute of ill tortoises with normal appearing shells, compared with 14-kd proteins of healthy tortoises. Conclusions and Clinical Relevance - The major protein components of shell scute of desert tortoises have amino acid composition and antigenic features of ?? keratins. Scute protein composition may be altered in tortoises with certain systemic illnesses.

  14. Hydroxylamine hydrochloride-acetic acid-soluble and -insoluble fractions of pelagic sediment: Readsorption revisited

    Science.gov (United States)

    Piper, D.Z.; Wandless, G.A.

    1992-01-01

    The extraction of the rare earth elements (REE) from deep-ocean pelagic sediment, using hydroxylamine hydrochloride-acetic acid, leads to the separation of approximately 70% of the bulk REE content into the soluble fraction and 30% into the insoluble fraction. The REE pattern of the soluble fraction, i.e., the content of REE normalized to average shale on an element-by-element basis and plotted against atomic number, resembles the pattern for seawater, whereas the pattern, as well as the absolute concentrations, in the insoluble fraction resembles the North American shale composite. These results preclude significant readsorption of the REE by the insoluble phases during the leaching procedure.

  15. Modeling heat resistance of Bacillus weihenstephanensis and Bacillus licheniformis spores as function of sporulation temperature and pH.

    Science.gov (United States)

    Baril, Eugénie; Coroller, Louis; Couvert, Olivier; Leguérinel, Ivan; Postollec, Florence; Boulais, Christophe; Carlin, Frédéric; Mafart, Pierre

    2012-05-01

    Although sporulation environmental factors are known to impact on Bacillus spore heat resistance, they are not integrated into predictive models used to calculate the efficiency of heating processes. This work reports the influence of temperature and pH encountered during sporulation on heat resistance of Bacillus weihenstephanensis KBAB4 and Bacillus licheniformis AD978 spores. A decrease in heat resistance (δ) was observed for spores produced either at low temperature, at high temperature or at acidic pH. Sporulation temperature and pH maximizing the spore heat resistance were identified. Heat sensitivity (z) was not modified whatever the sporulation environmental factors were. A resistance secondary model inspired by the Rosso model was proposed. Sporulation temperatures and pHs minimizing or maximizing the spore heat resistance (T(min(R)), T(opt(R)), T(max(R)), pH(min(R)) and pH(opt(R))) were estimated. The goodness of the model fit was assessed for both studied strains and literature data. The estimation of the sporulation temperature and pH maximizing the spore heat resistance is of great interest to produce spores assessing the spore inactivation in the heating processes applied by the food industry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Acylation of cellular proteins with endogenously synthesized fatty acids

    International Nuclear Information System (INIS)

    Towler, D.; Glaser, L.

    1986-01-01

    A number of cellular proteins contain covalently bound fatty acids. Previous studies have identified myristic acid and palmitic acid covalently linked to protein, the former usually attached to proteins by an amide linkage and the latter by ester or thio ester linkages. While in a few instances specific proteins have been isolated from cells and their fatty acid composition has been determined, the most frequent approach to the identification of protein-linked fatty acids is to biosynthetically label proteins with fatty acids added to intact cells. This procedure introduces possible bias in that only a selected fraction of proteins may be labeled, and it is not known whether the radioactive fatty acid linked to the protein is identical with that which is attached to the protein when the fatty acid is derived from endogenous sources. We have examined the distribution of protein-bound fatty acid following labeling with [ 3 H]acetate, a general precursor of all fatty acids, using BC 3 H1 cells (a mouse muscle cell line) and A431 cells (a human epidermoid carcinoma). Myristate, palmitate, and stearate account for essentially all of the fatty acids linked to protein following labeling with [ 3 H]acetate, but at least 30% of the protein-bound palmitate in these cells was present in amide linkage. In BC3H1 cells, exogenous palmitate becomes covalently bound to protein such that less than 10% of the fatty acid is present in amide linkage. These data are compatible with multiple protein acylating activities specific for acceptor protein fatty acid chain length and linkage

  17. Synthesis, structural, solubility and anticancer activity studies of salts using nucleobases and sulfonic acids coformer

    Science.gov (United States)

    Singh, Neetu; Singh, Udai P.; Nikhil, Kumar; Roy, Partha; Singh, Hariji

    2017-10-01

    The reactions of natural and unnatural nucleobases (cytosine (Cyt), adenine (Ade), 5-aminouracil (AU) and caffeine (Caff)) with sulfonic acids coformer (1,5-naphthalenedisulfonic acid, NDSA; 5-sulfosalicylic acid, SSA) resulted in the formation of salts viz. [NDSA.Cyt] (1), [NDSA.Ade] (2), [NDSA.AU] (3), [NDSA.Caff] (4), [SSA.Cyt] (5), [SSA.Ade] (6), [SSA.AU] (7), and [SSA.Caff] (8). The structural analysis revealed that salts 1, 4, 6 and 7 have intermolecular interactions between adjacent nucleobases which form two different homodimer shown in R22 (8) motif and assembled via complementary Nsbnd H⋯O and Nsbnd H⋯N interactions. However, in all other salts an intermediate supramolecular synthon pattern was observed between nucleobases and sulfonic acids. The lattice energy was also calculated by DFT to investigate whether salts were thermodynamically more stable than its coformer. The same was further confirmed by differential scanning calorimetry-thermogravimetric (DSC-TG) analysis. The anticancer activity study of individual nucleobases and their NDSA salts were also performed on human breast (MCF-7) and lung (A 549) cancer cell. The salts formation of nucleobases with sulfonic acids improved their solubility, thereby demonstrating up to 8-fold increase in solubility of nucleobases.

  18. Majority of cellular fatty acid acylated proteins are localized to the cytoplasmic surface of the plasma membrane

    International Nuclear Information System (INIS)

    Wilcox, C.A.; Olson, E.N.

    1987-01-01

    The BC 2 Hl muscle cell line was previously reported to contain a broad array of fatty acid acylated proteins. Palmitate was shown to be attached to membrane proteins posttranslationally through thiol ester linkages, whereas myristate was attached cotranslationally, or within seconds thereafter, to soluble and membrane-bound proteins through amide linkages. The temporal and subcellular differences between palmitate and myristate acylation suggested that these two classes of acyl proteins might follow different intracellular pathways to distinct subcellular membrane systems or organelles. In this study, the authors examined the subcellular localization of the major fatty acylated proteins in BC 4 Hl cells. Palmitate-containing proteins were localized to the plasma membrane, but only a subset of myristate-containing proteins was localized to this membrane fraction. The majority of acyl proteins were nonglycosylated and resistant to digestion with extracellular proteases, suggesting that they were not exposed to the external surface of the plasma membrane. Many proteins were, however, digested during incubation of isolated membranes with proteases, which indicates that these proteins were, however, digested during incubation of isolated membranes with proteases, which indicates that these proteins face the cytoplasm. Two-dimensional gel electrophoresis of proteins labeled with [ 3 H]palmitate and [ 3 H]myristate revealed that individual proteins were modified by only one of the two fatty acids and did not undergo both N-linked myristylation and ester-linked palmitylation. Together, these results suggest that the majority of cellular acyl proteins are routed to the cytoplasmic surface of the plasma membrane, and they raise the possibility that fatty acid acylation may play a role in intracellular sorting of nontransmembranous, nonglycosylated membrane proteins

  19. Drug-drug cocrystals of antituberculous 4-aminosalicylic acid: Screening, crystal structures, thermochemical and solubility studies.

    Science.gov (United States)

    Drozd, Ksenia V; Manin, Alex N; Churakov, Andrei V; Perlovich, German L

    2017-03-01

    Experimental multistage cocrystal screening of the antituberculous drug 4-aminosalicylic acid (PASA) has been conducted with a number of coformers (pyrazinamide (PYR), nicotinamide (NAM), isonicotinamide (iNAM), isoniazid (INH), caffeine (CAF) and theophylline (TPH)). The crystal structures of 4-aminosalicylic acid cocrystals with isonicotinamide ([PASA+iNAM] (2:1)) and methanol solvate with caffeine ([PASA+CAF+MeOH] (1:1:1)) have been determined by single X-ray diffraction experiments. For the first time for PASA cocrystals it has been found that the structural unit of the [PASA+iNAM] cocrystal (2:1) is formed by 2 types of heterosynthons: acid-pyridine and acid-amide. The desolvation study of the [PASA+CAF+MeOH] cocrystal solvate (1:1:1) has been conducted. The correlation models linking the melting points of the cocrystals with the melting points of the coformers used in this paper have been developed. The thermochemical and solubility properties for all the obtained cocrystals have been studied. Cocrystallization has been shown to lead not only to PASA solubility improving but also to its higher stability against the chemical decomposition. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Studies on the distribution of radioactivity in the organism and rate of incorporation of radioactivity into the tissue proteins of monogastric animals after intravenous injection of tracer amino acids

    International Nuclear Information System (INIS)

    Simon, O.; Muenchmeyer, R.; Bergner, H.; Zebrowska, T.

    1976-01-01

    Radioactive amino acids ( 14 C leucine and 3 H lysine) were administrated to pigs by means of a catheter tube into the jugular vein. Subsequently, the time pattern of the distribution of the specific amino acid radioactivity was followed in the TCE soluble and TCE precipitable fractions of the blood plasma (TCE = trichloroacetic acid). Rats were injected 14 C into the portal vein. The animals were killed after incorporation periods of 2 to 60 minutes, and the levels of specific radioactivity were estimated in the TCE soluble and TCE precipitable fractions of the blood plasma, in the liver and in the skeletal muscles. The experimental results indicated that the specific radioactivity of the tracer amino acids and the rate of incorporation of radioactivity into tissue proteins were influenced by the size of the free amino acid pool within the range of distribution of the tracer. An estimation of the magnitude of the pool of free amino acids within the distribution range of the tracer can be obtained from the curve pattern for the decline of specific radioactivity of the corresponding free amino acid in the blood plasma. This pool exhibits a high rate of turnover. In all studies made to evaluate in vivo processes of protein synthesis using radioactive tracer amino acids it will be particularly important that consideration is given to the specific radioactivity of the amino acid in the precursor pool for protein synthesis. (author)

  1. Manipulating fatty acid biosynthesis in microalgae for biofuel through protein-protein interactions.

    Directory of Open Access Journals (Sweden)

    Jillian L Blatti

    Full Text Available Microalgae are a promising feedstock for renewable fuels, and algal metabolic engineering can lead to crop improvement, thus accelerating the development of commercially viable biodiesel production from algae biomass. We demonstrate that protein-protein interactions between the fatty acid acyl carrier protein (ACP and thioesterase (TE govern fatty acid hydrolysis within the algal chloroplast. Using green microalga Chlamydomonas reinhardtii (Cr as a model, a structural simulation of docking CrACP to CrTE identifies a protein-protein recognition surface between the two domains. A virtual screen reveals plant TEs with similar in silico binding to CrACP. Employing an activity-based crosslinking probe designed to selectively trap transient protein-protein interactions between the TE and ACP, we demonstrate in vitro that CrTE must functionally interact with CrACP to release fatty acids, while TEs of vascular plants show no mechanistic crosslinking to CrACP. This is recapitulated in vivo, where overproduction of the endogenous CrTE increased levels of short-chain fatty acids and engineering plant TEs into the C. reinhardtii chloroplast did not alter the fatty acid profile. These findings highlight the critical role of protein-protein interactions in manipulating fatty acid biosynthesis for algae biofuel engineering as illuminated by activity-based probes.

  2. Bioreduction of Uranium(VI) Complexed with Citric Acid by Clostridia Affects its Structure and Mobility

    International Nuclear Information System (INIS)

    Francis, A.; Dodge, C.

    2008-01-01

    Uranium contamination of the environment from mining and milling operations, nuclear-waste disposal, and ammunition use is a widespread global problem. Natural attenuation processes such as bacterial reductive precipitation and immobilization of soluble uranium is gaining much attention. However, the presence of naturally occurring organic ligands can affect the precipitation of uranium. Here, we report that the anaerobic spore-forming bacteria Clostridia, ubiquitous in soils, sediments, and wastes, capable of reduction of Fe(III) to Fe(II), Mn(IV) to Mn(II), U(VI) to U(IV), Pu(IV) to Pu(III), and Tc(VI) to Tc(IV); reduced U(VI) associated with citric acid in a dinuclear 2:2 U(VI):citric acid complex to a biligand mononuclear 1:2 U(IV):citric acid complex, which remained in solution, in contrast to reduction and precipitation of uranium. Our findings show that U(VI) complexed with citric acid is readily accessible as an electron acceptor despite the inability of the bacterium to metabolize the complexed organic ligand. Furthermore, it suggests that the presence of organic ligands at uranium-contaminated sites can affect the mobility of the actinide under both oxic and anoxic conditions by forming such soluble complexes.

  3. Comparative analysis of amino acids and amino-acid derivatives in protein crystallization

    International Nuclear Information System (INIS)

    Ito, Len; Shiraki, Kentaro; Yamaguchi, Hiroshi

    2010-01-01

    New types of aggregation suppressors, such as amino acids and their derivatives, were focused on as fourth-component additives. Data were obtained that indicated that the additives promote protein crystallization. Optimal conditions for protein crystallization are difficult to determine because proteins tend to aggregate in saturated solutions. This study comprehensively evaluates amino acids and amino-acid derivatives as additives for crystallization. This fourth component of the solution increases the probability of crystallization of hen egg-white lysozyme in various precipitants owing to a decrease in aggregation. These results suggest that the addition of certain types of amino acids and amino-acid derivatives, such as Arg, Lys and esterified and amidated amino acids, is a simple method of improving the success rate of protein crystallization

  4. Effect of varying temperature on growth, morphology and soluble protein content of div I and div II mutant strains of bacillus sub tills

    International Nuclear Information System (INIS)

    Ahmed, A.; Sabri, A.N.

    2004-01-01

    In B.subtilis, cell division is controlled by div-genes which have been mapped on its circular chromosome. In the present work, div-mutant strains 1A316(div II), 1A317 and 1A318 (div I) were studied. These strains exhibited temperature sensitive cell division mutations. Colony morphology, cell morphology, staining behavior, growth rate and protein content of PY79 (wild type) and div-mutant strains (1A316, 1A317, 1A318) was studied at different temperatures ( 25 deg. Centi grade and 42 deg. with varying incubation periods(4, 16, 24, 48, 72,96 hrs). div-mutants differ from wild type (PY79) in colony morphology. Colony margin in PY79 was entire while in the div strains it is undulate. Staining behavior of cells as well as cell morphology i.e., cell size, cell types, formation of filaments/minicells were affected by high temperature. At higher temperature (42 deg. Centi grade), div-mutants undergo more severe lysis and degeneration as compare to wild type (PY79). Defective spores were produced by div-mutants at 25 deg. Centi grade and 42 deg. Centi grade. Tetrazolium overlay test was performed at 37 deg. Centi grade and 42 deg. Centi grade to check the spore germination ability of wild type and div-mutants. In 1A318, defective spores were produced at 37 deg. Centi grade, div-mutant was checked after 24 and 96 hrs at different temperatures (25, 37 and 42 deg. Centi grade). At all temperatures protein content were more in PY79 as compare to div-mutants. Also at 25 and 42 deg. Centi grade, protein content was more as compare to 37 deg. Centi grade. Protein contents was reduced at sporulation stages. Thus cell division mutations affect cell morphology, sporulation and germination processes in B.subtilis and thus are multifaceted mutations. (author)

  5. Mapping of Proteomic Composition on the Surfaces of Bacillus spores by Atomic Force Microscopy-based Immunolabeling

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Malkin, A J

    2008-06-02

    Atomic force microscopy provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g. viruses, bacteria and bacterial spores) at near molecular resolution in native conditions. Further development of atomic force microscopy in order to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We have applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  6. Some physicochemical and nutritional studies on Karkade (Hibiscus sabdariffa) seed proteins

    International Nuclear Information System (INIS)

    Ahmed, Saif Aldein Bashir

    1998-01-01

    Seeds of Karkade (Al-Rahad variety) were obtained from western Sudan, and investigated perliminary for their chemical composition, the oil of the seed also was investigated. The factors affecting protein extractability such as PH, salt type and concentration and solvent to flour ratio, were studied. The anti nutritional factors investigated were protease inhibitors, gossypol, phytates and tanins, means of inactivation such as heat treatment for trypsin inhibitor and differential solubility for phytates were proposed. Protein fractionation due to solubility was carried out. Other physiochemical properties included polyacrylamide gel electrophersis, ultra violet absorption spectrum and gel filtration pattern. The functional properties investigated were bulk density, solubility, water and oil absorption, emulsifying activity and viscosity. Karkade seed was found to be rich in protein, oil and mineral matter. The amino acid profile of karkade seed proteins indicated the presence of most of essential amino acids in adequate amounts. The relative net protein ratio (RNPR) was found to be 0.75. Protein digestibility-corrected amino acid score of karkade seed protein was found to be 0.63 ( compared to casein in 1.0). The molecular weights of the protein fractions investigated by SDS- PAGE were in the range of 12-82 kDa. UV absorption spectra reflects changes in the molecular structure (native proteins absorb at 280 nm and also interaction with other components e.g. nucleic acids, poly phenols.....etc). Gel filtration pattern reflect changes in molecular size

  7. Some physicochemical and nutritional studies on Karkade (Hibiscus sabdariffa) seed proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Saif Aldein Bashir [Department of Food Science and Technology, Faculty of Agriculture, University of Khartoum, Khatroum (Sudan)

    1998-01-01

    Seeds of Karkade (Al-Rahad variety) were obtained from western Sudan, and investigated perliminary for their chemical composition, the oil of the seed also was investigated. The factors affecting protein extractability such as PH, salt type and concentration and solvent to flour ratio, were studied. The anti nutritional factors investigated were protease inhibitors, gossypol, phytates and tanins, means of inactivation such as heat treatment for trypsin inhibitor and differential solubility for phytates were proposed. Protein fractionation due to solubility was carried out. Other physiochemical properties included polyacrylamide gel electrophersis, ultra violet absorption spectrum and gel filtration pattern. The functional properties investigated were bulk density, solubility, water and oil absorption, emulsifying activity and viscosity. Karkade seed was found to be rich in protein, oil and mineral matter. The amino acid profile of karkade seed proteins indicated the presence of most of essential amino acids in adequate amounts. The relative net protein ratio (RNPR) was found to be 0.75. Protein digestibility-corrected amino acid score of karkade seed protein was found to be 0.63 ( compared to casein in 1.0). The molecular weights of the protein fractions investigated by SDS- PAGE were in the range of 12-82 kDa. UV absorption spectra reflects changes in the molecular structure (native proteins absorb at 280 nm and also interaction with other components e.g. nucleic acids, poly phenols.....etc). Gel filtration pattern reflect changes in molecular size. 204 refs. , 35 tabs. , 8 figs.

  8. The participation of soluble factors in the omega-oxidation of fatty acids in the liver of the sheep

    International Nuclear Information System (INIS)

    Hare, W.R.; Wahle, K.W.

    1991-01-01

    The removal of soluble components from an ovine hepatic microsomal preparation decreased the omega-hydroxylation of dodecanoic and hexadecanoic acids. The results suggest that one or more soluble components play a role in the microsomal omega-hydroxylation of fatty acids. The possible roles in the reaction of catalase (known to stimulate the microsomal desaturations of fatty acids and alkylglycerols) and superoxide dismutase were investigated. The addition of these enzymes to the complete (but not the washed) microsomal preparation stimulated both the initial omega-hydroxylation reaction and the subsequent dehydrogenation reactions of the omega-oxidation pathway. The similarity of the effects of catalase and superoxide dismutase and stimulation of two different steps of the omega-oxidation pathway suggest that these agents are acting indirectly by removing active oxygen species rather than directly on the enzymes of microsomal fatty acid omega-hydroxylation

  9. Amino acid metabolism conflicts with protein diversity

    OpenAIRE

    Krick, Teresa; Shub, David A.; Verstraete, Nina; Ferreiro, Diego U.; Alonso, Leonardo G.; Shub, Michael; Sanchez, Ignacio E.

    2014-01-01

    The 20 protein-coding amino acids are found in proteomes with different relative abundances. The most abundant amino acid, leucine, is nearly an order of magnitude more prevalent than the least abundant amino acid, cysteine. Amino acid metabolic costs differ similarly, constraining their incorporation into proteins. On the other hand, a diverse set of protein sequences is necessary to build functional proteomes. Here, we present a simple model for a cost-diversity trade-off postulating that n...

  10. Effects of Limited Hydrolysis and High-Pressure Homogenization on Functional Properties of Oyster Protein Isolates.

    Science.gov (United States)

    Yu, Cuiping; Cha, Yue; Wu, Fan; Xu, Xianbing; Du, Ming

    2018-03-22

    In this study, the effects of limited hydrolysis and/or high-pressure homogenization (HPH) treatment in acid conditions on the functional properties of oyster protein isolates (OPI) were studied. Protein solubility, surface hydrophobicity, particle size distribution, zeta potential, foaming, and emulsifying properties were evaluated. The results showed that acid treatment led to the dissociation and unfolding of OPI. Subsequent treatment such as limited proteolysis, HPH, and their combination remarkably improved the functional properties of OPI. Acid treatment produced flexible aggregates, as well as reduced particle size and solubility. On the contrary, limited hydrolysis increased the solubility of OPI. Furthermore, HPH enhanced the effectiveness of the above treatments. The emulsifying and foaming properties of acid- or hydrolysis-treated OPI significantly improved. In conclusion, a combination of acid treatment, limited proteolysis, and HPH improved the functional properties of OPI. The improvements in the functional properties of OPI could potentiate the use of oyster protein and its hydrolysates in the food industry.

  11. Dynamic phase microscopy, a new method to detect viable and killed spores and to estimate the heterogeneity of spore populations

    Science.gov (United States)

    Tychinsky, Vladimir P.; Mulyukin, Andrey L.; Lisovskii, Vitalii V.; Nikolaev, Yury A.; Kretushev, Aleksander V.; Vyshenskaya, Tatyana V.; Suzina, Nataliya E.; Duda, Vitalii I.; El-Registan, Galina I.

    One of the challenging tasks in monitoring studies is to estimate heterogeneity of microbial populations by the physiological state and potential viability of individual cells, especially with regard of their ability to withstand various environmental assaults. Previously, we described some approaches based on electron microscopy methods to discriminate vegetative, dormant, and dead cells in both aged microbial cultures and environmental samples, including permafrost. We propose to extend the arsenal of microscopy methods for monitoring studies by a new non-invasive and informative method - dynamic phase microscopy (DPM). The substantial advantage of DPM is that it gives quantitative (digitized) data of undestroyed (living) microscopic objects, exemplified in our work by Bacillus licheniformis spores. Using DPM made it possible to record interference images of objects (spores) and to produce picture of their "phase thickness" (PT) that is the optical path difference in nm. Thus, it was demonstrated the remarkable difference in the PT of spores at different physiological states: dormant, germinating, and heat-killed spores had PT values of 80, 40-50, and 20 nm, respectively. The other found criterion to distinguish between spores was the PT fluctuations. In contrast to dormant and killed spores, the PT of germinating spores oscillated with amplitude of up to 7 nm, with typical frequencies of 1.3 and 3.4 Hz. A combination of the recorded PT values and PT fluctuations gave a key to detect viable and dead cells. Under the conditions that did not support germination (the lack of nutrients), we were able to follow the response of a single dormant spore and a spore population to heating from 25 °C to 70 °C. Thus, a very small temperature change (from 40 °C to 42 °C) under conditions non-favorable for germination, caused a drastic decrease in the spores' PT; the second drop in the PT values was observed during heating from 60 °C to 70 °C. These changes were

  12. Acid-regulated proteins induced by Streptococcus mutans and other oral bacteria during acid shock.

    Science.gov (United States)

    Hamilton, I R; Svensäter, G

    1998-10-01

    Our previous research has demonstrated that with the more aciduric oral bacteria, an acid shock to sub-lethal pH values results in the induction of an acid tolerance response that protects the cells at extremely low pH (pH 3.0-4.0) that kills unadapted control cells maintained at pH 7.5 (Oral Microbiol Immunol 1997: 12: 266-273). In this study, we were interested in comparing the protein profiles of acid-shocked and control cells of nine organisms from three acid-ogenic genera that could be categorized as strong, weak and non-acid responders in an attempt to identify proteins that could be classified as acid-regulated proteins and which may be important in the process of survival at very low pH. For this, log-phase cultures were rapidly acidified from pH 7.5 to 5.5 in the presence of [14C]-amino acids for varying periods up to 2 h, the period previously shown to be required for maximum induction of the acid response. The cells were extracted for total protein and subjected to one-dimensional sodium dodecyl sulfate-polyacrylamide chromatography with comparable control and acid-shocked protein profiles compared by scanning and computer analysis. Of particular interest were the proteins in the acid-shocked cells that showed enhanced labeling (i.e., synthesis) over the control cells, since these were considered acid-regulated proteins of importance in pH homeostasis. Streptococcus mutans LT11 generated the most rapid and complex pattern: a total of 36 acid-regulated proteins showing enhanced synthesis, with 25 appearing within the first 30 min of acid shock. The enhanced synthesis was transient with all proteins, with the exception of two with molecular weights of 50/49 and 33/32 kDa. Within the acid-regulated proteins were proteins having molecular weights comparable to the heat shock proteins and the various subunits of the membrane H+/ATPase. By comparison, the strong responder, Lactobacillus casei 151, showed the enhanced formation of only nine proteins within the

  13. Protein Design Using Unnatural Amino Acids

    Science.gov (United States)

    Bilgiçer, Basar; Kumar, Krishna

    2003-11-01

    With the increasing availability of whole organism genome sequences, understanding protein structure and function is of capital importance. Recent developments in the methodology of incorporation of unnatural amino acids into proteins allow the exploration of proteins at a very detailed level. Furthermore, de novo design of novel protein structures and function is feasible with unprecedented sophistication. Using examples from the literature, this article describes the available methods for unnatural amino acid incorporation and highlights some recent applications including the design of hyperstable protein folds.

  14. Corvitin restores metallothionein and glial fibrillary acidic protein levels in rat brain affected by pituitrin-izadrin

    OpenAIRE

    H. N. Shiyntum; O. O. Dovban; Y. P. Kovalchuk; T. Ya. Yaroshenko2; G. A. Ushakova1

    2017-01-01

    In this research, we investigated the effect of pituitrin-izadrin induced injury on the levels of metallothionein (MT) and soluble and filament forms of glial fibrillary acidic protein (GFAP) in the hippocampus, cerebellum, thalamus, and the cerebral cortex, and examined the effect of corvitin on the brain under the noted changes. Our results showed oppositely directed changes – a decrease in the level of MT and an increase in GFAP in the rat brain, with a tendency to astrogliosis development...

  15. Effect of plaster cast immobilization on the turnover rates of soluble proteins and lactate dehydrogenase isoenzymes of rabbit M. soleus

    Energy Technology Data Exchange (ETDEWEB)

    Edes, I.; Dosa, E.; Sohar, I.; Guba, F. (Orvostudomanyi Egyetem, Szeged (Hungary). Biokemiai Tanszek)

    1982-01-01

    In atrophized muscle the decreases of the activity of LDH isoenzymes can be explained partly by a 15 per cent decrease of the enzyme synthesis and partly by a 25 per cent increase in catabolism. The quantities of the soluble proteins and LDH were measured after intravenously administered /sup 3/H-leucin incorporation, from the musculus soleus. LDH was isolated by means of affinity chromatography. Radioactivity was determined in a Packard Tri-Carb scintillation counter. The synthesis rate of soluble proteins barely changed during immobilization. In the atrophized muscle the decrease of the amount of soluble proteins could be almost exclusively interpreted in terms of a 25 per cent enchancement of degradative process. The accelerated catabolism is most probably due to the proteolytic enzymes activated by immobilization.

  16. Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

    OpenAIRE

    Maree, M. David; Neuse, Eberhard W.; Erasmus, Elizabeth; Swarts, Jannie C.

    2007-01-01

    The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymer...

  17. Protein synthesis in the presence of carbamoyl-amino acids

    International Nuclear Information System (INIS)

    Kraus, L.M.; Stephens, M.C.

    1987-01-01

    The role of exogenous carbamoyl-amino acids in protein biosynthesis has been examined in vitro using a mixture of 14 C amino acids to label newly synthesized protein in human reticulocyte rich (8-18%) peripheral blood. Aliquots of the radiolabeled newly synthesized protein were acid precipitated, washed and the radioactivity measured. Control samples which measured the synthetic capacity of the blood were aliquots of the same blood- 14 C amino acid mixture without added carbamoyl-amino acids or cyanate. N-carbamoyl leucine alone or a 3 N-carbamoyl amino acid mixture of leucine, aspartic acid and tyrosine were used to test inhibition of protein synthesis. Also carbamoyl-amino acids were synthesized using cyanate and Pierce hydrolyzate amino acid calibration standards or the mixture of 14 C amino acids. In this system the carbamoylation of endogenous amino acids by cyanate up to 8 μmol/100μl showed a linear decrease in protein synthesis with time which is inversely related to the cyanate concentration. At greater cyanate levels the inhibition of protein synthesis reaches a plateau. When N-carbamoyl-amino acids only are present there is about a 50% decrease in the 14 C protein at 30 minutes as compared to the synthesis of 14 C protein without N-carbamoyl-amino acids. These results indicate that the presence of carbamoyl-amino acids interferes with protein synthesis

  18. Fatty acid oxidation in skeletal and cardiac muscle

    International Nuclear Information System (INIS)

    Glatz, J.F.C.

    1983-01-01

    The biochemical investigations described in this thesis deal with two aspects of fatty acid oxidation in muscle: a comparison of the use of cell-free and cellular systems for oxidation measurements, and studies on the assay and the role of the fatty acid binding protein in fatty acid metabolism. The fatty acid oxidation rates are determined radiochemically by the sum of 14 CO 2 and 14 C-labeled acid-soluble products formed during oxidation of [ 14 C]-fatty acids. A radiochemical procedure for the assay of fatty acid binding by proteins is described. (Auth.)

  19. Optical and structural properties of plasma-treated Cordyceps bassiana spores as studied by circular dichroism, absorption, and fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Geon Joon, E-mail: gjlee@kw.ac.kr; Sim, Geon Bo; Choi, Eun Ha [Plasma Bioscience Research Center/Department of Electrical and Biological Physics, Kwangwoon University, Seoul 139-701 (Korea, Republic of); Kwon, Young-Wan [KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701 (Korea, Republic of); Kim, Jun Young; Jang, Siun; Kim, Seong Hwan, E-mail: piceae@naver.com [Department of Microbiology and Institute of Basic Sciences, Dankook University, Cheonan 330-714 (Korea, Republic of)

    2015-01-14

    To understand the killing mechanism of fungal spores by plasma treatment, the optical, structural, and biological properties of the insect pathogenic fungus Cordyceps bassiana spores were studied. A nonthermal atmospheric-pressure plasma jet (APPJ) was used to treat the spores in aqueous solution. Optical emission spectra of the APPJ acquired in air indicated emission peaks corresponding to hydroxyl radicals and atomic oxygen. When the APPJ entered the aqueous solution, additional reactive species were derived from the interaction of plasma radicals with the aqueous solution. Fluorescence and absorption spectroscopy confirmed the generation of hydroxyl radicals and hydrogen peroxide in the plasma-activated water (PAW). Spore counting showed that plasma treatment significantly reduced spore viability. Absorption spectroscopy, circular dichroism (CD) spectroscopy, and agarose gel electrophoresis of the DNA extracted from plasma-treated spores showed a reduction in spore DNA content. The magnitude of the dip in the CD spectrum was lower in the plasma-treated spores than in the control, indicating that plasma treatment causes structural modifications and/or damage to cellular components. Tryptophan fluorescence intensity was lower in the plasma-treated spores than in the control, suggesting that plasma treatment modified cell wall proteins. Changes in spore viability and DNA content were attributed to structural modification of the cell wall by reactive species coming from the APPJ and the PAW. Our results provided evidence that the plasma radicals and the derived reactive species play critical roles in fungal spore inactivation.

  20. Determination of solubility isotherms of barium and strontium nitrates in the system acetic acid-water at 250 C

    International Nuclear Information System (INIS)

    Hubicki, W.; Piskorek, M.

    1976-01-01

    Investigastions of the solubility of barium and strontium nitrates were carried out in the system: acetic acid - water at 25 0 C. When one compares the isotherms of solubility of barium and strontium nitrates, one can observe that it is possible to separate the admixtures of barium from strontium nitrates as a result of fractional crystallization of these nitrates from actic acid solution at the temperatures lower than 31.3 0 C, i.e. below the temperature of transformation: Sr(NO 3 ) 2 . 4H 2 O reversible to Sr(NO 3 ) 2 + 4H 2 O for aqueous solution. (author)

  1. Sphagnum moss disperses spores with vortex rings.

    Science.gov (United States)

    Whitaker, Dwight L; Edwards, Joan

    2010-07-23

    Sphagnum spores, which have low terminal velocities, are carried by turbulent wind currents to establish colonies many kilometers away. However, spores that are easily kept aloft are also rapidly decelerated in still air; thus, dispersal range depends strongly on release height. Vascular plants grow tall to lift spores into sufficient wind currents for dispersal, but nonvascular plants such as Sphagnum cannot grow sufficiently high. High-speed videos show that exploding capsules of Sphagnum generate vortex rings to efficiently carry spores high enough to be dispersed by turbulent air currents. Spores launched ballistically at similar speeds through still air would travel a few millimeters and not easily reach turbulent air. Vortex rings are used by animals; here, we report vortex rings generated by plants.

  2. Biofilm formation and sporulation by Bacillus cereus on a stainless steel surface and subsequent resistance of vegetative cells and spores to chlorine, chlorine dioxide, and a peroxyacetic acid-based sanitizer.

    Science.gov (United States)

    Ryu, Jee-Hoon; Beuchat, Larry R

    2005-12-01

    Biofilm formation by Bacillus cereus 038-2 on stainless steel coupons, sporulation in the biofilm as affected by nutrient availability, temperature, and relative humidity, and the resistance of vegetative cells and spores in biofilm to sanitizers were investigated. Total counts in biofilm formed on coupons immersed in tryptic soy broth (TSB) at 12 and 22 degrees C consisted of 99.94% of vegetative cells and 0.06% of spores. Coupons on which biofilm had formed were immersed in TSB or exposed to air with 100, 97, 93, or 85% relative humidity. Biofilm on coupons immersed in TSB at 12 degrees C for an additional 6 days or 22 degrees C for an additional 4 days contained 0.30 and 0.02% of spores, respectively, whereas biofilm exposed to air with 100 or 97% relative humidity at 22 degrees C for 4 days contained 10 and 2.5% of spores, respectively. Sporulation did not occur in biofilm exposed to 93 or 85% relative humidity at 22 degrees C. Treatment of biofilm on coupons that had been immersed in TSB at 22 degrees C with chlorine (50 microg/ml), chlorine dioxide (50 microg/ml), and a peroxyacetic acid-based sanitizer (Tsunami 200, 40 microg/ml) for 5 min reduced total cell counts (vegetative cells plus spores) by 4.7, 3.0, and 3.8 log CFU per coupon, respectively; total cell counts in biofilm exposed to air with 100% relative humidity were reduced by 1.5, 2.4, and 1.1 log CFU per coupon, respectively, reflecting the presence of lower numbers of vegetative cells. Spores that survived treatment with chlorine dioxide had reduced resistance to heat. It is concluded that exposure of biofilm formed by B. cereus exposed to air at high relative humidity (> or =97%) promotes the production of spores. Spores and, to a lesser extent, vegetative cells embedded in biofilm are protected against inactivation by sanitizers. Results provide new insights to developing strategies to achieve more effective sanitation programs to minimize risks associated with B. cereus in biofilm formed on

  3. Heterologous Expression of the Carrot Hsp17.7 gene Increased Growth, Cell Viability, and Protein Solubility in Transformed Yeast (Saccharomyces cerevisiae) under Heat, Cold, Acid, and Osmotic Stress Conditions.

    Science.gov (United States)

    Ko, Eunhye; Kim, Minhye; Park, Yunho; Ahn, Yeh-Jin

    2017-08-01

    In industrial fermentation of yeast (Saccharomyces cerevisiae), culture conditions are often modified from the optimal growth conditions of the cells to maintain large-scale cultures and/or to increase recombinant protein production. However, altered growth conditions can be stressful to yeast cells resulting in reduced cell growth and viability. In this study, a small heat shock protein gene from carrot (Daucus carota L.), Hsp17.7, was inserted into the yeast genome via homologous recombination to increase tolerance to stress conditions that can occur during industrial culture. A DNA construct, Translational elongation factor gene promoter-carrot Hsp17.7 gene-Phosphoribosyl-anthranilate isomerase gene (an auxotrophic marker), was generated by a series of PCRs and introduced into the chromosome IV of the yeast genome. Immunoblot analysis showed that carrot Hsp17.7 accumulated in the transformed yeast cell lines. Growth rates and cell viability of these cell lines were higher than control cell lines under heat, cold, acid, and hyperosmotic stress conditions. Soluble protein levels were higher in the transgenic cell lines than control cell lines under heat and cold conditions, suggesting the molecular chaperone function of the recombinant Hsp17.7. This study showed that a recombinant DNA construct containing a HSP gene from carrot was successfully expressed in yeast by homologous recombination and increased tolerances to abiotic stress conditions.

  4. Cleaved thioredoxin fusion protein enables the crystallization of poorly soluble ERα in complex with synthetic ligands

    International Nuclear Information System (INIS)

    Cura, Vincent; Gangloff, Monique; Eiler, Sylvia; Moras, Dino; Ruff, Marc

    2007-01-01

    A new crystallization strategy: the presence of cleaved thioredoxin fusion is critical for crystallization of the estrogen nuclear receptor ligand binding domain in complex with synthetic ligands. This novel technique should be regarded as an interesting alternative for crystallization of difficult proteins. The ligand-binding domain (LBD) of human oestrogen receptor α was produced in Escherichia coli as a cleavable thioredoxin (Trx) fusion in order to improve solubility. Crystallization trials with either cleaved and purified LBD or with the purified fusion protein both failed to produce crystals. In another attempt, Trx was not removed from the LBD after endoproteolytic cleavage and its presence promoted nucleation and subsequent crystal growth, which allowed the structure determination of two different LBD–ligand–coactivator peptide complexes at 2.3 Å resolution. This technique is likely to be applicable to other low-solubility proteins

  5. Adaptation of the spore discharge mechanism in the basidiomycota.

    Directory of Open Access Journals (Sweden)

    Jessica L Stolze-Rybczynski

    Full Text Available Spore discharge in the majority of the 30,000 described species of Basidiomycota is powered by the rapid motion of a fluid droplet, called Buller's drop, over the spore surface. In basidiomycete yeasts, and phytopathogenic rusts and smuts, spores are discharged directly into the airflow around the fungal colony. Maximum discharge distances of 1-2 mm have been reported for these fungi. In mushroom-forming species, however, spores are propelled over much shorter ranges. In gilled mushrooms, for example, discharge distances of <0.1 mm ensure that spores do not collide with opposing gill surfaces. The way in which the range of the mechanism is controlled has not been studied previously.In this study, we report high-speed video analysis of spore discharge in selected basidiomycetes ranging from yeasts to wood-decay fungi with poroid fruiting bodies. Analysis of these video data and mathematical modeling show that discharge distance is determined by both spore size and the size of the Buller's drop. Furthermore, because the size of Buller's drop is controlled by spore shape, these experiments suggest that seemingly minor changes in spore morphology exert major effects upon discharge distance.This biomechanical analysis of spore discharge mechanisms in mushroom-forming fungi and their relatives is the first of its kind and provides a novel view of the incredible variety of spore morphology that has been catalogued by traditional taxonomists for more than 200 years. Rather than representing non-selected variations in micromorphology, the new experiments show that changes in spore architecture have adaptive significance because they control the distance that the spores are shot through air. For this reason, evolutionary modifications to fruiting body architecture, including changes in gill separation and tube diameter in mushrooms, must be tightly linked to alterations in spore morphology.

  6. Threshold value of enamel mineral solubility and dental erosion after consuming acidic soft drinks

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2011-09-01

    Full Text Available Background: Dental erosion is irreversible and can caused by acidic soft drink consumption. Dental erosion prevention had already been done, but it still has not been satisfying since the consumption of acidic soft drink is still high. There is still no explanation about the threshold value of enamel mineral solubility and the occurance of dental erosion after consuming acidic soft drink. Purpose: This research is aimed to find the threshold value of enamel mineral solubility and dental erosion before and after consuming acidic soft drinks. Methods: Subjects of the research are saliva and enamel of 12 rabbits, which have some criteria such as age > 70 days, body weight > 600 grams, and teeth considered to be healthy. The sample devided equally into 4 groups. Each of those marmooths was given a drink as much as 2.5 cc/consumption (there are 1, 2 and 3× per day by using syringe without injection needle. Salivary minerals then were examined by using atomic absorption spectrophotometric (ASS, while dental erosion was examined using scanning electron microscop (SEM. The data were analyzed by using Paired t-test. Results: It is known that the threshold value of enamel mineral solubility (K, Na, Fe, Mg, Cl, P, Ca, F, C has significant difference (p < 0.05 after being exposed to folic acid. Meanwhile, Fe did not have significant difference (p = 0.090 after being exposed to citric acid. Similarly, C did not have significant difference (p = 0.063 after being exposed to bicarbonate acid. Furthermore, it is also known that the threshold time value of dental erosion are on the 105th day for folic acid, on the 111th day for citric acid, and on the 117th day for bicarbonate acid. Conclusion: Threshold value of enamel mineral solubility before and after consuming soft drinks containing acid is different. Based on the threshold value of dental erosion, it is known that folic acid is the most erosive acid.Latar belakang: Erosi gigi bersifat irreversible

  7. Effect of individual or combined treatment by γ-irradiation or temperature (high or low) on bacillus subtilis spores and its application for sterilization of ground beef

    International Nuclear Information System (INIS)

    El-Zawahry, Y.A.; Mostafa, S.A.; Awny, N.M.

    1986-01-01

    The combination of two lethal agents such as irradiation and temperature (high or sub zero) resulted in synergistic death or B. subtilis spores (as indicated by decrease in the thermal D-value). The extent of this synergism in killing a spore population depended mainly on the sequence on application of the two physical agents. Irradiation-temperature (high or sub zero) sequence killed more but injured less B. subtilis spores than temperature irradiation sequence or irradiation and temperature applied separately. Storage at -20 0 C killed more spores than storage at -2 0 C if carried after irradiation, while the reverse was true of storage was prior irradiation. An irradiation dose of 8 KGY followed by thermal exposure to 70 0 C for 1 hr is suggested for the sterilization of ground beef. Irradiation induced certain quantitative changes on the amino-N, protein-N, RNA and DNA of the first subcultures of irradiated spores with stimulatory effect at low irradiation doses and inhibitory effect at the high irradiation doses. This might explain the increased sensitivity of irradiated spores to subsequent exposure to unfavourable temperature (high or sub zero). Exposure of B. subtilis spore to 70 0 C induced a stimulation in the amino- and protein-N of the resulting cells while exposure to 80 0 C resulted in a significant decrease in the amino-N. The protein-N remained more or less the same

  8. VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture.

    Science.gov (United States)

    Wang, Fengfeng; Dijksterhuis, Jan; Wyatt, Timon; Wösten, Han A B; Bleichrodt, Robert-Jan

    2015-01-01

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by ΔveA fits the 8- to 17-fold decrease in counted spore numbers. Notably, morphology of the ΔveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger ΔveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.

  9. Selectivity in protein degradation during sporulation of Bacillus subtilis

    International Nuclear Information System (INIS)

    Mitani, Takahiko; Kadota, Hajime

    1976-01-01

    The breakdown of cellular protein was investigated in Bacillus subtilis ATCC 6051 labeled with glycine-2- 3 H or L-phenylalanine-U- 14 C at the different stages of vegetative growth and sporulation. The growth of the culture was determined by measuring optical density at 660 nm. The heat-resistant spores were scored by plating after heating at 80 deg C for 10 minutes. A question whether the turnover of glycine-labeled protein is similar to that of phenylalanine-labeled protein was experimentally studied. The patterns obtained with the glycine-labeled protein were different from those of phenylalanine-labeled protein. This was not multiple turnover. The cellular protein which was labeled with glycine at an early stage of sporulation showed rapid degradation, but the degradation of the protein labeled with glycine at later stages did not occur at all. Another question whether the labeled glycine incorporated into cells at the different stages of growth and sporulation was present in the spore coat fraction of matured spores was studied. Experiment demonstrated that the glycine incorporated into cells at the late sporulation stage was mainly utilized for the biosynthesis of the spore coat protein. These data suggest that the spore coat protein which contains relatively large amount of glycine is rarely subject to further degradation. (Iwakiri, K.)

  10. Forensic Discrimination of Concrete Pieces by Elemental Analysis of Acid-soluble Component with Inductively Coupled Plasma-Mass Spectrometry.

    Science.gov (United States)

    Kasamatsu, Masaaki; Igawa, Takao; Suzuki, Shinichi; Suzuki, Yasuhiro

    2018-01-01

    Since fragments of concrete can be evidence of crime, a determination of whether or not they come from the same origin is required. The authors focused on nitric acid-soluble components in the fragments of concrete. As a result of qualitative analysis with ICP-MS, it was confirmed that elements such as Cu, Zn, Rb, Sr, Zr, Ba, La, Ce, Nd, and Pb were contained in the fragments. After the nitric acid-soluble components in the fragments of concrete were separated by dissolving them in nitric acid, the concentrations of these elements in the dissolved solution were quantitatively determined by ICP-MS. The concentration ratios of nine elements compared to La were used as indicators. By comparing these indicators, it was possible to discriminate between the fragments of concrete.

  11. Sensitivity of thermally treated Bacillus subtilis spores to subsequent irradiation

    International Nuclear Information System (INIS)

    Mostafa, S.A.; El-Zawahry, Y.A.; Awny, N.M.

    1986-01-01

    B. subtilis spores exposed to thermal treatment at 70 or 80 0 C for 1 hr were more sensitive to subsequent radiation exposure than non-heated spores. Deactivation of previously heated spores by increasing dose of 0-radiation followed an exponential function while, for non-heated spores a shoulder followed by exponential deactivation was noticed. Combined heat-radiation treatment exhibited a synergistic effect on spore deactivation at low irradiation doses, while at high irradiation doses, the effect was more or less additive. Added values of spore injury was higher for B. subtilis spores that received heat and radiation separately than the observed injury for spores that received combined treatment (heat followed by radiation). Results of spore deactivation and injury due to heat followed by radiation treatment are discussed in comparison to those of spores that received radiation-heat sequence

  12. PROTEIN ANTIMIKROB DARI TANAMAN TRICHOSANTHES

    Directory of Open Access Journals (Sweden)

    Sukma D

    2008-08-01

    Full Text Available The research was aimed to study morphology, growth, development, pest and disease of 3 Trichosanthes species, initiate shoots, callus and hairy root culture in vitro, analyze chitinase and peroxidase activities and the effect of salicylic acid (SA and etefon (ETF on the chitinase and peroxidase activities of crude protein extract from Trichosanthes, and evaluate in vitro antifungal activity of crude protein extract of Trichosanthes. The results of the research showed the differences of morphological characters, growth habit of T. cucumerina var. anguina, T.tricuspidata and the differences of pest and diseases problem of T. quinquangulata. T. cucumerina var. anguina and T. quinquangulata. T. tricuspidata had the highest chitinase activity in crude protein extract of in vitro shoots, calli and plant roots and peroxidase activity in plant roots grown in field. T. cucumerina var. anguina showed the highest chitinase and peroxidase activities in crude protein extract of plant roots grown in field and calli. Chitinase and peroxidase activities of calli crude protein extract of T. tricuspidata could be increased by SA and ETF. Adversely, ETF decreased the peroxidase activity of calli crude protein exract ofT. tricuspidata. In T. cucumerina var. anguina, SA could not increase the chitinase activity but increase the peroxidase activity. The crude protein from in vitro shoots of T. tricuspidata could inhibited the spore germination of Fusarium sp. from T. cucumerina var. anguina, Fusarium oxysporum from shallot, Puccinia arachidis from peanut and Pseudoperonospora cubensis from cucumber. The protein could not inhibit spore germination of Curvularia eragrostidis from Dendrobium orchids

  13. An electrophoretic study of the soluble lens proteins from the Indian mackerel, Rastrelliger kanagurta (Cuv)

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.

    Soluble eye lens nuclei proteins of the Indian mackerel Rastrelliger kanagurta were studied by cellogel electrophoresis, to see whether there are any intra species variations. A distinct pattern characterised by the number of bands, mobility...

  14. Intracellular transport of fat-soluble vitamins A and E.

    Science.gov (United States)

    Kono, Nozomu; Arai, Hiroyuki

    2015-01-01

    Vitamins are compounds that are essential for the normal growth, reproduction and functioning of the human body. Of the 13 known vitamins, vitamins A, D, E and K are lipophilic compounds and are therefore called fat-soluble vitamins. Because of their lipophilicity, fat-soluble vitamins are solubilized and transported by intracellular carrier proteins to exert their actions and to be metabolized properly. Vitamin A and its derivatives, collectively called retinoids, are solubilized by intracellular retinoid-binding proteins such as cellular retinol-binding protein (CRBP), cellular retinoic acid-binding protein (CRABP) and cellular retinal-binding protein (CRALBP). These proteins act as chaperones that regulate the metabolism, signaling and transport of retinoids. CRALBP-mediated intracellular retinoid transport is essential for vision in human. α-Tocopherol, the main form of vitamin E found in the body, is transported by α-tocopherol transfer protein (α-TTP) in hepatic cells. Defects of α-TTP cause vitamin E deficiency and neurological disorders in humans. Recently, it has been shown that the interaction of α-TTP with phosphoinositides plays a critical role in the intracellular transport of α-tocopherol and is associated with familial vitamin E deficiency. In this review, we summarize the mechanisms and biological significance of the intracellular transport of vitamins A and E. © 2014 The Authors. Traffic published by John Wiley & Sons Ltd.

  15. Regulation of intestinal protein metabolism by amino acids.

    Science.gov (United States)

    Bertrand, Julien; Goichon, Alexis; Déchelotte, Pierre; Coëffier, Moïse

    2013-09-01

    Gut homeostasis plays a major role in health and may be regulated by quantitative and qualitative food intake. In the intestinal mucosa, an intense renewal of proteins occurs, at approximately 50% per day in humans. In some pathophysiological conditions, protein turnover is altered and may contribute to intestinal or systemic diseases. Amino acids are key effectors of gut protein turnover, both as constituents of proteins and as regulatory molecules limiting intestinal injury and maintaining intestinal functions. Many studies have focused on two amino acids: glutamine, known as the preferential substrate of rapidly dividing cells, and arginine, another conditionally essential amino acid. The effects of glutamine and arginine on protein synthesis appear to be model and condition dependent, as are the involved signaling pathways. The regulation of gut protein degradation by amino acids has been minimally documented until now. This review will examine recent data, helping to better understand how amino acids regulate intestinal protein metabolism, and will explore perspectives for future studies.

  16. Absorption of proteins and amino acids

    International Nuclear Information System (INIS)

    Jeejeebhoy, K.N.

    1976-01-01

    Although the absorption of proteins and amino acids is an important issue in nutrition, its measurement is not common because of the methodological difficulties. Complications are attributable in particular to the magnitude of endogenous protein secretion and to the diversity of absorption mechanisms for amino acids either as individual units or as peptides. Methods for studying absorption include balance techniques, tolerance tests, tracer techniques using proteins or amino acids labelled with 131 I, 3 H, or 15 N, intestinal perfusion studies, and others; they must be selected according to the nature of the information sought. Improvements over the current methods would be useful. (author)

  17. Differential distribution of proteins and lipids in detergent-resistant and detergent-soluble domains in rod outer segment plasma membranes and disks.

    Science.gov (United States)

    Elliott, Michael H; Nash, Zack A; Takemori, Nobuaki; Fliesler, Steven J; McClellan, Mark E; Naash, Muna I

    2008-01-01

    Membrane heterogeneity plays a significant role in regulating signal transduction and other cellular activities. We examined the protein and lipid components associated with the detergent-resistant membrane (DRM) fractions from retinal rod outer segment (ROS) disk and plasma membrane-enriched preparations. Proteomics and correlative western blot analysis revealed the presence of alpha and beta subunits of the rod cGMP-gated ion channel and glucose transporter type 1, among other proteins. The glucose transporter was present exclusively in ROS plasma membrane (not disks) and was highly enriched in DRMs, as was the cGMP-gated channel beta-subunit. In contrast, the majority of rod opsin and ATP-binding cassette transporter A4 was localized to detergent-soluble domains in disks. As expected, the cholesterol : fatty acid mole ratio was higher in DRMs than in the corresponding parent membranes (disk and plasma membranes, respectively) and was also higher in disks compared to plasma membranes. Furthermore, the ratio of saturated : polyunsaturated fatty acids was also higher in DRMs compared to their respective parent membranes (disk and plasma membranes). These results confirm that DRMs prepared from both disks and plasma membranes are enriched in cholesterol and in saturated fatty acids compared to their parent membranes. The dominant fatty acids in DRMs were 16 : 0 and 18 : 0; 22 : 6n3 and 18 : 1 levels were threefold higher and twofold lower, respectively, in disk-derived DRMs compared to plasma membrane-derived DRMs. We estimate, based on fatty acid recovery that DRMs account for only approximately 8% of disks and approximately 12% of ROS plasma membrane.

  18. pH-metric solubility. 3. Dissolution titration template method for solubility determination.

    Science.gov (United States)

    Avdeef, A; Berger, C M

    2001-12-01

    The main objective of this study was to develop an effective potentiometric saturation titration protocol for determining the aqueous intrinsic solubility and the solubility-pH profile of ionizable molecules, with the specific aim of overcoming incomplete dissolution conditions, while attempting to shorten the data collection time. A modern theory of dissolution kinetics (an extension of the Noyes-Whitney approach) was applied to acid-base titration experiments. A thermodynamic method was developed, based on a three-component model, to calculate interfacial, diffusion-layer, and bulk-water reactant concentrations in saturated solutions of ionizable compounds perturbed by additions of acid/base titrant, leading to partial dissolution of the solid material. Ten commercial drugs (cimetidine, diltiazem hydrochloride, enalapril maleate, metoprolol tartrate, nadolol, propoxyphene hydrochloride, quinine hydrochloride, terfenadine, trovafloxacin mesylate, and benzoic acid) were chosen to illustrate the new titration methodology. It was shown that the new method is about 10 times faster in determining equilibrium solubility constants, compared to the traditional saturation shake-flask methods.

  19. Hypochlorous and peracetic acid induced oxidation of dairy proteins.

    Science.gov (United States)

    Kerkaert, Barbara; Mestdagh, Frédéric; Cucu, Tatiana; Aedo, Philip Roger; Ling, Shen Yan; De Meulenaer, Bruno

    2011-02-09

    Hypochlorous and peracetic acids, both known disinfectants in the food industry, were compared for their oxidative capacity toward dairy proteins. Whey proteins and caseins were oxidized under well controlled conditions at pH 8 as a function of the sanitizing concentration. Different markers for protein oxidation were monitored. The results established that the protein carbonyl content was a rather unspecific marker for protein oxidation, which did not allow one to differentiate the oxidant used especially at the lower concentrations. Cysteine, tryptophan, and methionine were proven to be the most vulnerable amino acids for degradation upon hypochlorous and peracetic acid treatment, while tyrosine was only prone to degradation in the presence of hypochlorous acid. Hypochlorous acid induced oxidation gave rise to protein aggregation, while during peracetic acid induced oxidation, no high molecular weight aggregates were observed. Protein aggregation upon hypochlorous acid oxidation could primarily be linked to tryptophan and tyrosine degradation.

  20. Protein shedding in urothelial bladder cancer: prognostic implications of soluble urinary EGFR and EpCAM.

    Science.gov (United States)

    Bryan, R T; Regan, H L; Pirrie, S J; Devall, A J; Cheng, K K; Zeegers, M P; James, N D; Knowles, M A; Ward, D G

    2015-03-17

    Better biomarkers must be found to develop clinically useful urine tests for bladder cancer. Proteomics can be used to identify the proteins released by cancer cell lines and generate candidate markers for developing such tests. We used shotgun proteomics to identify proteins released into culture media by eight bladder cancer cell lines. These data were compared with protein expression data from the Human Protein Atlas. Epidermal growth factor receptor (EGFR) was identified as a candidate biomarker and measured by ELISA in urine from 60 noncancer control subjects and from 436 patients with bladder cancer and long-term clinical follow-up. Bladder cancer cell lines shed soluble EGFR ectodomain. Soluble EGFR is also detectable in urine and is highly elevated in some patients with high-grade bladder cancer. Urinary EGFR is an independent indicator of poor bladder cancer-specific survival with a hazard ratio of 2.89 (95% CI 1.81-4.62, Pbladder cancer-specific survival and have prognostic value over and above that provided by standard clinical observations. Measuring urinary EGFR and EpCAM may represent a simple and useful approach for fast-tracking the investigation and treatment of patients with the most aggressive bladder cancers.

  1. The decision to germinate is regulated by divergent molecular networks in spores and seeds

    DEFF Research Database (Denmark)

    Vesty, Eleanor F.; Saidi, Younousse; Moody, Laura A.

    2016-01-01

    , the role of abscisic acid and diterpenes (gibberellins) in germination assumed much greater importance as land plant evolution progressed. We conclude that the endogenous hormone signalling networks mediating germination in response to the environment may have evolved independently in spores and seeds...

  2. Heat-Induced Soluble Protein Aggregates from Mixed Pea Globulins and β-Lactoglobulin.

    Science.gov (United States)

    Chihi, Mohamed-Lazhar; Mession, Jean-luc; Sok, Nicolas; Saurel, Rémi

    2016-04-06

    The present work investigates the formation of protein aggregates (85 °C, 60 min incubation) upon heat treatment of β-lactoglobulin (βlg)-pea globulins (Glob) mixtures at pH 7.2 and 5 mM NaCl from laboratory-prepared protein isolates. Various βlg/Glob weight ratios were applied, for a total protein concentration of 2 wt % in admixture. Different analytical methods were used to determine the aggregation behavior of "mixed" aggregates, that is, surface hydrophobicity and also sulfhydryl content, protein interactions by means of SDS-PAGE electrophoresis, and molecule size distribution by DLS and gel filtration. The production of "mixed" thermal aggregates would involve both the formation of new disulfide bonds and noncovalent interactions between the denatured βlg and Glob subunits. The majority of "mixed" soluble aggregates displayed higher molecular weight and smaller diameter than those for Glob heated in isolation. The development of pea-whey protein "mixed" aggregates may help to design new ingredients for the control of innovative food textures.

  3. Recovering folic acid and its identification on mixed pastes of tempeh and fermented vegetable as natural source of folic acid

    Science.gov (United States)

    Susilowati, Agustine; Aspiyanto, Maryati, Yati; Melanie, Hakiki; Lotulung, Puspa D.

    2017-11-01

    Mixing between tempeh and both fermented broccoli (Brassica oleracea) and spinach (Amaranthus sp.) were conducted to achieve mixed pastes as natural source of folic acid for 'smart food'. Mixing was performed on soy, mung bean, and kidney bean tempehs with both fermented broccoli and spinach at ratio of 1 : 1, 1 : 2, 1 : 3, 1 : 4, 1 : 5 and 1 : 6, respectively. Result of experimental activity showed that pulverizing ratio becoming more and more low will decrease total solids, soluble protein and N-Amino, but fluctuates on folic acid in mixed paste. Based on folic acid equivalent and the best fermented vegetable efficiency, optimization condition was reached in paste with combination between mung beans tempeh and fermented spinach at ratio of 1 : 2 by increasing folic acid concentration of 83.18 % (0.83 times), dissolved protein 432.29 % (4.32 times) and N-amino 55.36 % (0,55 times). While, it is occurred a lowering total solids 22.16 % (0.22 times) when compared with folic acid, soluble protein, N-amino, and total solids on initial materials of mung bean tempeh. In this condition, it is achieved folic acid monomer with molecular weight (MW) 148.14 Da. with relative intensity 100 %, and glutamic acid monomer 443.50 Da.with relative intensity 0.07 %.

  4. Large-scale proteome analysis of abscisic acid and ABSCISIC ACID INSENSITIVE3-dependent proteins related to desiccation tolerance in Physcomitrella patens

    International Nuclear Information System (INIS)

    Yotsui, Izumi; Serada, Satoshi; Naka, Tetsuji; Saruhashi, Masashi; Taji, Teruaki; Hayashi, Takahisa; Quatrano, Ralph S.; Sakata, Yoichi

    2016-01-01

    Desiccation tolerance is an ancestral feature of land plants and is still retained in non-vascular plants such as bryophytes and some vascular plants. However, except for seeds and spores, this trait is absent in vegetative tissues of vascular plants. Although many studies have focused on understanding the molecular basis underlying desiccation tolerance using transcriptome and proteome approaches, the critical molecular differences between desiccation tolerant plants and non-desiccation plants are still not clear. The moss Physcomitrella patens cannot survive rapid desiccation under laboratory conditions, but if cells of the protonemata are treated by the phytohormone abscisic acid (ABA) prior to desiccation, it can survive 24 h exposure to desiccation and regrow after rehydration. The desiccation tolerance induced by ABA (AiDT) is specific to this hormone, but also depends on a plant transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3). Here we report the comparative proteomic analysis of AiDT between wild type and ABI3 deleted mutant (Δabi3) of P. patens using iTRAQ (Isobaric Tags for Relative and Absolute Quantification). From a total of 1980 unique proteins that we identified, only 16 proteins are significantly altered in Δabi3 compared to wild type after desiccation following ABA treatment. Among this group, three of the four proteins that were severely affected in Δabi3 tissue were Arabidopsis orthologous genes, which were expressed in maturing seeds under the regulation of ABI3. These included a Group 1 late embryogenesis abundant (LEA) protein, a short-chain dehydrogenase, and a desiccation-related protein. Our results suggest that at least three of these proteins expressed in desiccation tolerant cells of both Arabidopsis and the moss are very likely to play important roles in acquisition of desiccation tolerance in land plants. Furthermore, our results suggest that the regulatory machinery of ABA- and ABI3-mediated gene expression for desiccation

  5. Large-scale proteome analysis of abscisic acid and ABSCISIC ACID INSENSITIVE3-dependent proteins related to desiccation tolerance in Physcomitrella patens

    Energy Technology Data Exchange (ETDEWEB)

    Yotsui, Izumi, E-mail: izumi.yotsui@riken.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Serada, Satoshi, E-mail: serada@nibiohn.go.jp [Laboratory of Immune Signal, National Institute of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka, 567-0085 (Japan); Naka, Tetsuji, E-mail: tnaka@nibiohn.go.jp [Laboratory of Immune Signal, National Institute of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka, 567-0085 (Japan); Saruhashi, Masashi, E-mail: s13db001@mail.saitama-u.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Taji, Teruaki, E-mail: t3teruak@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Hayashi, Takahisa, E-mail: t4hayash@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Quatrano, Ralph S., E-mail: rsq@wustl.edu [Department of Biology, Washington University in St. Louis, St. Louis, MO, 63130-4899 (United States); Sakata, Yoichi, E-mail: sakata@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan)

    2016-03-18

    Desiccation tolerance is an ancestral feature of land plants and is still retained in non-vascular plants such as bryophytes and some vascular plants. However, except for seeds and spores, this trait is absent in vegetative tissues of vascular plants. Although many studies have focused on understanding the molecular basis underlying desiccation tolerance using transcriptome and proteome approaches, the critical molecular differences between desiccation tolerant plants and non-desiccation plants are still not clear. The moss Physcomitrella patens cannot survive rapid desiccation under laboratory conditions, but if cells of the protonemata are treated by the phytohormone abscisic acid (ABA) prior to desiccation, it can survive 24 h exposure to desiccation and regrow after rehydration. The desiccation tolerance induced by ABA (AiDT) is specific to this hormone, but also depends on a plant transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3). Here we report the comparative proteomic analysis of AiDT between wild type and ABI3 deleted mutant (Δabi3) of P. patens using iTRAQ (Isobaric Tags for Relative and Absolute Quantification). From a total of 1980 unique proteins that we identified, only 16 proteins are significantly altered in Δabi3 compared to wild type after desiccation following ABA treatment. Among this group, three of the four proteins that were severely affected in Δabi3 tissue were Arabidopsis orthologous genes, which were expressed in maturing seeds under the regulation of ABI3. These included a Group 1 late embryogenesis abundant (LEA) protein, a short-chain dehydrogenase, and a desiccation-related protein. Our results suggest that at least three of these proteins expressed in desiccation tolerant cells of both Arabidopsis and the moss are very likely to play important roles in acquisition of desiccation tolerance in land plants. Furthermore, our results suggest that the regulatory machinery of ABA- and ABI3-mediated gene expression for desiccation

  6. Proteomic identification of Drosophila melanogaster male accessory gland proteins, including a pro-cathepsin and a soluble γ-glutamyl transpeptidase

    Directory of Open Access Journals (Sweden)

    Sajid Mohammed

    2006-05-01

    Full Text Available Background In Drosophila melanogaster, the male seminal fluid contains proteins that are important for reproductive success. Many of these proteins are synthesised by the male accessory glands and are secreted into the accessory gland lumen, where they are stored until required. Previous studies on the identification of Drosophila accessory gland products have largely focused on characterisation of male-specific accessory gland cDNAs from D. melanogaster and, more recently, Drosophila simulans. In the present study, we have used a proteomics approach without any sex bias to identify proteins in D. melanogaster accessory gland secretions. Results Thirteen secreted accessory gland proteins, including seven new accessory gland proteins, were identified by 2D-gel electrophoresis combined with mass spectrometry of tryptic fragments. They included protein-folding and stress-response proteins, a hormone, a lipase, a serpin, a cysteine-rich protein and two peptidases, a pro-enzyme form of a cathepsin K-like cysteine peptidase and a γ-glutamyl transpeptidase. Enzymatic studies established that accessory gland secretions contain a cysteine peptidase zymogen that can be activated at low pH. This peptidase may have a role in the processing of female and other male-derived proteins, but is unlikely to be involved in the processing of the sex peptide. γ-Glutamyl transpeptidases are type II integral membrane proteins; however, the identified AG γ-glutamyl transpeptidase (GGT-1 is unusual in that it is predicted to be a soluble secreted protein, a prediction that is supported by biochemical evidence. GGT-1 is possibly involved in maintaining a protective redox environment for sperm. The strong γ-glutamyl transpeptidase activity found in the secretions provides an explanation for the observation that glutamic acid is the most abundant free amino acid in accessory gland secretions of D. melanogaster. Conclusion We have applied biochemical approaches, not used

  7. Proteomic identification of Drosophila melanogaster male accessory gland proteins, including a pro-cathepsin and a soluble gamma-glutamyl transpeptidase.

    Science.gov (United States)

    Walker, Michael J; Rylett, Caroline M; Keen, Jeff N; Audsley, Neil; Sajid, Mohammed; Shirras, Alan D; Isaac, R Elwyn

    2006-05-02

    In Drosophila melanogaster, the male seminal fluid contains proteins that are important for reproductive success. Many of these proteins are synthesised by the male accessory glands and are secreted into the accessory gland lumen, where they are stored until required. Previous studies on the identification of Drosophila accessory gland products have largely focused on characterisation of male-specific accessory gland cDNAs from D. melanogaster and, more recently, Drosophila simulans. In the present study, we have used a proteomics approach without any sex bias to identify proteins in D. melanogaster accessory gland secretions. Thirteen secreted accessory gland proteins, including seven new accessory gland proteins, were identified by 2D-gel electrophoresis combined with mass spectrometry of tryptic fragments. They included protein-folding and stress-response proteins, a hormone, a lipase, a serpin, a cysteine-rich protein and two peptidases, a pro-enzyme form of a cathepsin K-like cysteine peptidase and a gamma-glutamyl transpeptidase. Enzymatic studies established that accessory gland secretions contain a cysteine peptidase zymogen that can be activated at low pH. This peptidase may have a role in the processing of female and other male-derived proteins, but is unlikely to be involved in the processing of the sex peptide. gamma-Glutamyl transpeptidases are type II integral membrane proteins; however, the identified AG gamma-glutamyl transpeptidase (GGT-1) is unusual in that it is predicted to be a soluble secreted protein, a prediction that is supported by biochemical evidence. GGT-1 is possibly involved in maintaining a protective redox environment for sperm. The strong gamma-glutamyl transpeptidase activity found in the secretions provides an explanation for the observation that glutamic acid is the most abundant free amino acid in accessory gland secretions of D. melanogaster. We have applied biochemical approaches, not used previously, to characterise

  8. Influence of cold stress on contents of soluble sugars, vitamin C and free amino acids including gamma-aminobutyric acid (GABA) in spinach (Spinacia oleracea).

    Science.gov (United States)

    Yoon, Young-Eun; Kuppusamy, Saranya; Cho, Kye Man; Kim, Pil Joo; Kwack, Yong-Bum; Lee, Yong Bok

    2017-01-15

    The contents of soluble sugars (sucrose, fructose, glucose, maltose and raffinose), vitamin C and free amino acids (34 compounds, essential and non-essential) were quantified in open-field and greenhouse-grown spinaches in response to cold stress using liquid chromatography. In general, greenhouse cultivation produced nutritionally high value spinach in a shorter growing period, where the soluble sugars, vitamin C and total amino acids concentrations, including essential were in larger amounts compared to those grown in open-field scenarios. Further, low temperature exposure of spinach during a shorter growth period resulted in the production of spinach with high sucrose, ascorbate, proline, gamma-aminobutyric acid, valine and leucine content, and these constitute the most important energy/nutrient sources. In conclusion, cultivation of spinach in greenhouse at a low temperature (4-7°C) and exposure for a shorter period (7-21days) before harvest is recommended. This strategy will produce a high quality product that people can eat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Water-Soluble Dried Blood Spot in Protein Analysis: A Proof-of-Concept Study.

    Science.gov (United States)

    Rosting, Cecilie; Gjelstad, Astrid; Halvorsen, Trine Grønhaug

    2015-08-04

    In the present work human chorionic gonadotropin (hCG) was used as a model protein in a proof-of-concept study combining water-soluble dried blood spot (DBS) material in liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based protein analysis. A water-soluble material consisting of commercially available carboxymethyl cellulose (CMC) was evaluated as sampling material for this purpose. The material dissolved readily at physiological pH. Different sample preparation methods were evaluated, and in the final method, 15 μL of whole blood was deposited and dried on CMC before the whole spot was dissolved prior to cleanup by immunoaffinity extraction, tryptic digest, and preconcentration by solid-phase extraction (SPE). The results indicated complete dissolution of hCG from the spots, acceptable limit of detection (LOD) (0.1 IU/mL), linearity (R(2) = 0.959), accuracy (16%), and precision (≤22%). Long-term stability (45 days) of hCG in dried spots at reduced temperatures (≤8 °C) was also demonstrated. The analyte recovery was comparable to the commercially available nonsolvable cellulose material (FTA DMPK-C card).

  10. Thermodynamic functions for solubility of 3-nitro-o-toluic acid in nine organic solvents from T = (283.15 to 318.15) K and apparent thermodynamic properties of solutions

    International Nuclear Information System (INIS)

    Li, Xinbao; Wang, Mingju; Du, Cunbin; Cong, Yang; Zhao, Hongkun

    2017-01-01

    Highlights: • Solubilities of 3-nitro-o-toluic acid in nine organic solvents were determined. • The solubilities were correlated by using four thermodynamic models. • The mixing properties of solution were computed based on Wilson model. - Abstract: Separation of 3-nitro-o-toluic acid from its isomeric mixtures has essential significance in industry. In this work, by using isothermal saturation method, the solid-liquid equilibrium for 3-nitro-o-toluic acid in nine organic solvents (acetonitrile, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, acetone, 1,4-dioxane and 2-butanone) were obtained experimentally within a temperature range from (283.15 to 318.15) K under atmosphere pressure of 101.2 kPa, and the solubility values of 3-nitro-o-toluic acid in these solvents were determined by a high-performance liquid chromatography. Within the studied temperature range, the mole fraction solubility of 3-nitro-o-toluic acid in selected organic solvents increased with increasing temperature. Except for ethyl acetate, the descending order of the mole fraction solubility values were as follow: 1,4-dioxane > acetone > 2-butanone > methanol > ethanol > isopropanol > n-propanol > acetonitrile. The solubility values determined for 3-nitro-o-toluic acid in the selected solvents were correlated and back calculated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of RAD and RMSD obtained with the four models were 0.67% and 4.02 × 10 −4 , respectively. In general, the four thermodynamic models were all acceptable for describing the solubility behaviour of 3-nitro-o-toluic acid in these solvents. In addition, the apparent mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were calculated. The acquired solubility data and thermodynamic studies would be very important in optimizing the separation process of 3-nitro-o-toluic acid from

  11. [Survival of Bacillus anthracis spores in various tannery baths].

    Science.gov (United States)

    Mendrycka, M; Mierzejewski, J

    2000-01-01

    The influence of tannery baths: liming, deliming, bating, pickling, tanning, retannage on the survival and on the germination dynamism of B. anthracis spores (Sterne strain) was investigated. The periods and the conditions of this influence were established according to technological process of cow hide tannage. Practically after every bath some part of the spores remained vital. The most effective killing of spores occurred after pickling, liming and deliming. Inversely, the most viable spores remained after bating and retannage process. The lack of correlation that was observed between survival and germination of spores after retannage bath can be explained by different mechanism of spores germination inhibition and their killing.

  12. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Lamoolphak, Wiwat [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Goto, Motonobu [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Sasaki, Mitsuru [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Suphantharika, Manop [Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400 (Thailand); Muangnapoh, Chirakarn [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Prommuag, Chattip [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Shotipruk, Artiwan [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand)]. E-mail: artiwan.s@chula.ac.th

    2006-10-11

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products.

  13. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    International Nuclear Information System (INIS)

    Lamoolphak, Wiwat; Goto, Motonobu; Sasaki, Mitsuru; Suphantharika, Manop; Muangnapoh, Chirakarn; Prommuag, Chattip; Shotipruk, Artiwan

    2006-01-01

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products

  14. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    International Nuclear Information System (INIS)

    Khoza, Phindile; Antunes, Edith; Chen, Ji-Yao; Nyokong, Tebello

    2013-01-01

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by 1 H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: ► A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. ► The conjugate is water soluble even though the phthalocyanine alone is not. ► The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. ► Triplet quantum yields decreased for the conjugate

  15. Interactions between Therapeutic Proteins and Acrylic Acid Leachable.

    Science.gov (United States)

    Liu, Dengfeng; Nashed-Samuel, Yasser; Bondarenko, Pavel V; Brems, David N; Ren, Da

    2012-01-01

    Leachables are chemical compounds that migrate from manufacturing equipment, primary containers and closure systems, and packaging components into biopharmaceutical and pharmaceutical products. Acrylic acid (at concentration around 5 μg/mL) was detected as leachable in syringes from one of the potential vendors (X syringes). In order to evaluate the potential impact of acrylic acid on therapeutic proteins, an IgG 2 molecule was filled into a sterilized X syringe and then incubated at 45 °C for 45 days in a pH 5 acetate buffer. We discovered that acrylic acid can interact with proteins at three different sites: (1) the lysine side chain, (2) the N-terminus, and (3) the histidine side chain, by the Michael reaction. In this report, the direct interactions between acrylic acid leachable and a biopharmaceutical product were demonstrated and the reaction mechanism was proposed. Even thought a small amount (from 0.02% to 0.3%) of protein was found to be modified by acrylic acid, the modified protein can potentially be harmful due to the toxicity of acrylic acid. After being modified by acrylic acid, the properties of the therapeutic protein may change due to charge and hydrophobicity variations. Acrylic acid was detected to migrate from syringes (Vendor X) into a therapeutic protein solution (at a concentration around 5 μg/mL). In this study, we discovered that acrylic acid can modify proteins at three different sites: (1) the lysine side chain, 2) the N-terminus, and 3) the histidine side chain, by the Michael reaction. In this report, the direct interactions between acrylic acid leachable and a biopharmaceutical product were demonstrated and the reaction mechanism was proposed.

  16. Asynchronous spore germination in isogenic natural isolates of Saccharomyces paradoxus.

    Science.gov (United States)

    Stelkens, Rike B; Miller, Eric L; Greig, Duncan

    2016-05-01

    Spores from wild yeast isolates often show great variation in the size of colonies they produce, for largely unknown reasons. Here we measure the colonies produced from single spores from six different wild Saccharomyces paradoxus strains. We found remarkable variation in spore colony sizes, even among spores that were genetically identical. Different strains had different amounts of variation in spore colony sizes, and variation was not affected by the number of preceding meioses, or by spore maturation time. We used time-lapse photography to show that wild strains also have high variation in spore germination timing, providing a likely mechanism for the variation in spore colony sizes. When some spores from a laboratory strain make small colonies, or no colonies, it usually indicates a genetic or meiotic fault. Here, we demonstrate that in wild strains spore colony size variation is normal. We discuss and assess potential adaptive and non-adaptive explanations for this variation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Small proteins link coat and cortex assembly during sporulation in Bacillus subtilis

    Science.gov (United States)

    Ebmeier, Sarah E.; Tan, Irene S.; Clapham, Katie Rose; Ramamurthi, Kumaran S.

    2015-01-01

    Summary Mature spores of the bacterium Bacillus subtilis are encased by two concentric shells: an inner shell (the ‘cortex’), made of peptidoglycan; and an outer proteinaceous shell (the ‘coat’), whose basement layer is anchored to the surface of the developing spore via a 26-amino-acid-long protein called SpoVM. During sporulation, initiation of cortex assembly depends on the successful initiation of coat assembly, but the mechanisms that co-ordinate the morphogenesis of both structures are largely unknown. Here, we describe a sporulation pathway involving SpoVM and a 37-amino-acid-long protein named ‘CmpA’ that is encoded by a previously un-annotated gene and is expressed under control of two sporulation-specific transcription factors (σE and SpoIIID). CmpA localized to the surface of the developing spore and deletion of cmpA resulted in cells progressing through the sporulation programme more quickly. Overproduction of CmpA did not affect normal growth or cell division, but delayed entry into sporulation and abrogated cortex assembly. In those cells that had successfully initiated coat assembly, CmpA was removed by a posttranslational mechanism, presumably in order to overcome the sporulation inhibition it imposed. We propose a model in which CmpA participates in a developmental checkpoint that ensures the proper orchestration of coat and cortex morphogenesis by repressing cortex assembly until coat assembly successfully initiates. PMID:22463703

  18. Utilization of paramagnetic relaxation enhancements for high-resolution NMR structure determination of a soluble loop-rich protein with sparse NOE distance restraints

    International Nuclear Information System (INIS)

    Furuita, Kyoko; Kataoka, Saori; Sugiki, Toshihiko; Hattori, Yoshikazu; Kobayashi, Naohiro; Ikegami, Takahisa; Shiozaki, Kazuhiro; Fujiwara, Toshimichi; Kojima, Chojiro

    2015-01-01

    NMR structure determination of soluble proteins depends in large part on distance restraints derived from NOE. In this study, we examined the impact of paramagnetic relaxation enhancement (PRE)-derived distance restraints on protein structure determination. A high-resolution structure of the loop-rich soluble protein Sin1 could not be determined by conventional NOE-based procedures due to an insufficient number of NOE restraints. By using the 867 PRE-derived distance restraints obtained from the NOE-based structure determination procedure, a high-resolution structure of Sin1 could be successfully determined. The convergence and accuracy of the determined structure were improved by increasing the number of PRE-derived distance restraints. This study demonstrates that PRE-derived distance restraints are useful in the determination of a high-resolution structure of a soluble protein when the number of NOE constraints is insufficient

  19. Microwave-induced facile synthesis of water-soluble fluorogenic alginic acid derivatives.

    Science.gov (United States)

    Chhatbar, Mahesh U; Meena, Ramavatar; Prasad, Kamalesh; Chejara, Dharmesh R; Siddhanta, A K

    2011-04-01

    A facile microwave-induced method was developed for synthesizing water-soluble fluorescent derivatives of alginic acid (ALG) with four different diamines, hydrazine (HY), ethylenediamine (EDA), 1,6-hexanediamine (HDA), and 1,4-cyclohexanediamine (CHDA), followed by a cross-linking reaction with a natural cross linker genipin. The ethylenediamine derivative of alginic acid (ALG-EDA) exhibited good fluorescent activity, which upon cross linking was enhanced threefold. The other amide derivatives, for example, ALG-HY, ALG-HDA, and ALG-CHDA, were not fluorescent, but their respective crosslinked products exhibited excellent fluorescent activity. The fluorescence intensity had an inverse correlation with the number of carbon atoms present in the amine, which in turn was a function of degree of substitution (DS). These fluorescent polysaccharide derivatives are of potential utility in the domain of sensor applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Rugged single domain antibody detection elements for Bacillus anthracis spores and vegetative cells.

    Directory of Open Access Journals (Sweden)

    Scott A Walper

    Full Text Available Significant efforts to develop both laboratory and field-based detection assays for an array of potential biological threats started well before the anthrax attacks of 2001 and have continued with renewed urgency following. While numerous assays and methods have been explored that are suitable for laboratory utilization, detection in the field is often complicated by requirements for functionality in austere environments, where limited cold-chain facilities exist. In an effort to overcome these assay limitations for Bacillus anthracis, one of the most recognizable threats, a series of single domain antibodies (sdAbs were isolated from a phage display library prepared from immunized llamas. Characterization of target specificity, affinity, and thermal stability was conducted for six sdAb families isolated from rounds of selection against the bacterial spore. The protein target for all six sdAb families was determined to be the S-layer protein EA1, which is present in both vegetative cells and bacterial spores. All of the sdAbs examined exhibited a high degree of specificity for the target bacterium and its spore, with affinities in the nanomolar range, and the ability to refold into functional antigen-binding molecules following several rounds of thermal denaturation and refolding. This research demonstrates the capabilities of these sdAbs and their potential for integration into current and developing assays and biosensors.

  1. A novel water-based process produces eco-friendly bio-adhesive made from green cross-linked soybean soluble polysaccharide and soy protein.

    Science.gov (United States)

    Yuan, Cheng; Chen, Mingsong; Luo, Jing; Li, Xiaona; Gao, Qiang; Li, Jianzhang

    2017-08-01

    In this study, an eco-friendly soy protein adhesive was developed that utilized two components from soybean meal without addition of any toxic material. A plant-based, water-soluble and inexpensive soybean soluble polysaccharide was used as the novel renewable material to combine with soy protein to produce a soy protein adhesive. Three-plywood was fabricated with the resulting adhesive, and its wet shear strength was measured. The results showed the wet shear strength of plywood bonded by the adhesive reached 0.99MPa, meeting the water resistance requirement for interior use panels. This improvement was attributed to the following reasons: (1) Combination of cross-linked soybean soluble polysaccharide and soy protein formed an interpenetrating network structure, improving the thermal stability and water resistance of the cured adhesive. (2) Adding CL-SSPS decreased the adhesive viscosity to 15.14Pas, which increased the amount of the adhesive that penetrate the wood's surface and formed more interlocks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Corvitin restores metallothionein and glial fibrillary acidic protein levels in rat brain affected by pituitrin-izadrin

    Directory of Open Access Journals (Sweden)

    H. N. Shiyntum

    2017-06-01

    Full Text Available In this research, we investigated the effect of pituitrin-izadrin induced injury on the levels of metallothionein (MT and soluble and filament forms of glial fibrillary acidic protein (GFAP in the hippocampus, cerebellum, thalamus, and the cerebral cortex, and examined the effect of corvitin on the brain under the noted changes. Our results showed oppositely directed changes – a decrease in the level of MT and an increase in GFAP in the rat brain, with a tendency to astrogliosis development, under the influence of systemic deficiencies in myocardial function. The use of corvitin at a dose of 42 mg/kg for five days after a cardiac attack caused by pituitary-izadrin leads to recovery in the balance of the studied proteins.

  3. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    International Nuclear Information System (INIS)

    Makarska-Bialokoz, Magdalena; Borowski, Piotr

    2015-01-01

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H 2 TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10 5 mol −1 . The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H 2 TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated

  4. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    Energy Technology Data Exchange (ETDEWEB)

    Makarska-Bialokoz, Magdalena, E-mail: makarska@hektor.umcs.lublin.pl [Department of Inorganic Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 2, 20-031 Lublin (Poland); Borowski, Piotr [Faculty of Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 3, 20-031 Lublin (Poland)

    2015-04-15

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H{sub 2}TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10{sup 5} mol{sup −1}. The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H{sub 2}TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated.

  5. Lysophosphatidic acids are new substrates for the phosphatase domain of soluble epoxide hydrolase.

    Science.gov (United States)

    Oguro, Ami; Imaoka, Susumu

    2012-03-01

    Soluble epoxide hydrolase (sEH) is a bifunctional enzyme that has a C-terminus epoxide hydrolase domain and an N-terminus phosphatase domain. The endogenous substrates of epoxide hydrolase are known to be epoxyeicosatrienoic acids, but the endogenous substrates of the phosphatase activity are not well understood. In this study, to explore the substrates of sEH, we investigated the inhibition of the phosphatase activity of sEH toward 4-methylumbelliferyl phosphate by using lecithin and its hydrolyzed products. Although lecithin itself did not inhibit the phosphatase activity, the hydrolyzed lecithin significantly inhibited it, suggesting that lysophospholipid or fatty acid can inhibit it. Next, we investigated the inhibition of phosphatase activity by lysophosphatidyl choline, palmitoyl lysophosphatidic acid, monopalmitoyl glycerol, and palmitic acid. Palmitoyl lysophosphatidic acid and fatty acid efficiently inhibited phosphatase activity, suggesting that lysophosphatidic acids (LPAs) are substrates for the phosphatase activity of sEH. As expected, palmitoyl, stearoyl, oleoyl, and arachidonoyl LPAs were efficiently dephosphorylated by sEH (Km, 3-7 μM; Vmax, 150-193 nmol/min/mg). These results suggest that LPAs are substrates of sEH, which may regulate physiological functions of cells via their metabolism.

  6. Genotyping of single spore isolates of a Pasteuria penetrans population occurring in Florida using SNP-based markers.

    Science.gov (United States)

    Joseph, S; Schmidt, L M; Danquah, W B; Timper, P; Mekete, T

    2017-02-01

    To generate single spore lines of a population of bacterial parasite of root-knot nematode (RKN), Pasteuria penetrans, isolated from Florida and examine genotypic variation and virulence characteristics exist within the population. Six single spore lines (SSP), 16SSP, 17SSP, 18SSP, 25SSP, 26SSP and 30SSP were generated. Genetic variability was evaluated by comparing single-nucleotide polymorphisms (SNPs) in six protein-coding genes and the 16S rRNA gene. An average of one SNP was observed for every 69 bp in the 16S rRNA, whereas no SNPs were observed in the protein-coding sequences. Hierarchical cluster analysis of 16S rRNA sequences placed the clones into three distinct clades. Bio-efficacy analysis revealed significant heterogeneity in the level virulence and host specificity between the individual clones. The SNP markers developed to the 5' hypervariable region of the 16S rRNA gene may be useful in biotype differentiation within a population of P. penetrans. This study demonstrates an efficient method for generating single spore lines of P. penetrans and gives a deep insight into genetic heterogeneity and varying level of virulence exists within a population parasitizing a specific Meloidogyne sp. host. The results also suggest that the application of generalist spore lines in nematode management may achieve broad RKN control. © 2016 The Society for Applied Microbiology.

  7. Indole and 3-indolylacetonitrile inhibit spore maturation in Paenibacillus alvei

    Directory of Open Access Journals (Sweden)

    Cho Moo

    2011-05-01

    Full Text Available Abstract Background Bacteria use diverse signaling molecules to ensure the survival of the species in environmental niches. A variety of both Gram-positive and Gram-negative bacteria produce large quantities of indole that functions as an intercellular signal controlling diverse aspects of bacterial physiology. Results In this study, we sought a novel role of indole in a Gram-positive bacteria Paenibacillus alvei that can produce extracellular indole at a concentration of up to 300 μM in the stationary phase in Luria-Bertani medium. Unlike previous studies, our data show that the production of indole in P. alvei is strictly controlled by catabolite repression since the addition of glucose and glycerol completely turns off the indole production. The addition of exogenous indole markedly inhibits the heat resistance of P. alvei without affecting cell growth. Observation of cell morphology with electron microscopy shows that indole inhibits the development of spore coats and cortex in P. alvei. As a result of the immature spore formation of P. alvei, indole also decreases P. alvei survival when exposed to antibiotics, low pH, and ethanol. Additionally, indole derivatives also influence the heat resistance; for example, a plant auxin, 3-indolylacetonitrile dramatically (2900-fold decreased the heat resistance of P. alvei, while another auxin 3-indoleacetic acid had a less significant influence on the heat resistance of P. alvei. Conclusions Together, our results demonstrate that indole and plant auxin 3-indolylacetonitrile inhibit spore maturation of P. alvei and that 3-indolylacetonitrile presents an opportunity for the control of heat and antimicrobial resistant spores of Gram-positive bacteria.

  8. Identification and characterization of a spore-like morphotype in chronically starved Mycobacterium avium subsp. paratuberculosis cultures.

    Directory of Open Access Journals (Sweden)

    Elise A Lamont

    Full Text Available Mycobacteria are able to enter into a state of non-replication or dormancy, which may result in their chronic persistence in soil, aquatic environments, and permissive hosts. Stresses such as nutrient deprivation and hypoxia provide environmental cues to enter a persistent state; however, a clear definition of the mechanism that mycobacteria employ to achieve this remains elusive. While the concept of sporulation in mycobacteria is not novel, it continues to spark controversy and challenges our perceptions of a non-replication. We investigated the potential role of sporulation in one-year old broth cultures of Mycobacterium subsp. paratuberculosis (MAP. We show that dormant cultures of MAP contain a mix of vegetative cells and a previously unknown morphotype resembling a spore. These spore-like structures can be enriched for using sporulating media. Furthermore, purified MAP spore forms survive exposure to heat, lysozyme and proteinase K. Heat-treated spores are positive for MAP 16SrRNA and IS900. MAP spores display enhanced infectivity as well as maintain acid-fast characteristics upon germination in a well-established bovine macrophage model. This is the first study to demonstrate a new MAP morphotype possessing spore-like qualities. Data suggest that sporulation may be a viable mechanism by which MAP accomplishes persistence in the host and/or environment. Thus, our current understanding of mycobacterial persistence, pathogenesis, epidemiology and rational drug and vaccine design may need to be reevaluated.

  9. Soluble inhibitors/deactivators of cellulase enzymes from lignocellulosic biomass.

    Science.gov (United States)

    Kim, Youngmi; Ximenes, Eduardo; Mosier, Nathan S; Ladisch, Michael R

    2011-04-07

    Liquid hot water, steam explosion, and dilute acid pretreatments of lignocellulose generate soluble inhibitors which hamper enzymatic hydrolysis as well as fermentation of sugars to ethanol. Toxic and inhibitory compounds will vary with pretreatment and include soluble sugars, furan derivatives (hydroxymethyl fulfural, furfural), organic acids (acetic, formic and, levulinic acid), and phenolic compounds. Their effect is seen when an increase in the concentration of pretreated biomass in a hydrolysis slurry results in decreased cellulose conversion, even though the ratio of enzyme to cellulose is kept constant. We used lignin-free cellulose, Solka Floc, combined with mixtures of soluble components released during pretreatment of wood, to prove that the decrease in the rate and extent of cellulose hydrolysis is due to a combination of enzyme inhibition and deactivation. The causative agents were extracted from wood pretreatment liquid using PEG surfactant, activated charcoal or ethyl acetate and then desorbed, recovered, and added back to a mixture of enzyme and cellulose. At enzyme loadings of either 1 or 25mg protein/g glucan, the most inhibitory components, later identified as phenolics, decreased the rate and extent of cellulose hydrolysis by half due to both inhibition and precipitation of the enzymes. Full enzyme activity occurred when the phenols were removed. Hence detoxification of pretreated woods through phenol removal is expected to reduce enzyme loadings, and therefore reduce enzyme costs, for a given level of cellulose conversion. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. New pressure and temperature effects on bacterial spores

    Science.gov (United States)

    Mathys, A.; Heinz, V.; Knorr, D.

    2008-07-01

    The mechanism of inactivation of bacterial spores by heat and pressure is still a matter of discussion. Obviously, the change of the dissociation equilibrium under pressure and temperature plays a dominant role in inactivation of microorganisms. Heat and pressure inactivation of Geobacillus. stearothermophilus spores at different initial pH-values in ACES and phosphate buffer confirmed this view. Thermal inactivation in ACES buffer at 122°C resulted in higher logarithmic reductions. Contrary, after pressure treatment at 900 MPa with 80°C phosphate buffer showed higher inactivation. These results indicated the different dissociation equilibrium shifts in buffer systems by heat and pressure. Due to preparation, storage and handling of highly concentrated spore suspensions the clumping and the formation of aggregates can hardly be avoided. Consequently, the impact of the agglomeration size distribution on the quantitative assessment of G. stearothermophilus spore inactivation was determined by using a three-fold dynamic optical backreflexion measurement. Two limiting cases have been discriminated in mathematical modelling: three dimensional, spherical packing for maximum spore count and two dimensional, circular packing for minimum spore count of a particular agglomerate. Thermal inactivation studies have been carried out in thin glass capillaries, where by using numerical simulations the non isothermal conditions were modelled and taken into account. It is shown that the shoulder formation often found in thermal spore inactivation can sufficiently be described by first-order inactivation kinetics when the agglomeration size is considered. In case of high pressure inactivation agglomerations could be strongly changed by high forces at compression and especially decompression phase. The physiological response of Bacillus licheniformis spores to high pressure was investigated using multiparameter flow cytometry. Spores were treated by high pressure at 150 MPa with 37

  11. New pressure and temperature effects on bacterial spores

    Energy Technology Data Exchange (ETDEWEB)

    Mathys, A; Knorr, D [Berlin University of Technology, Department of Food Biotechnology and Food Process Engineering, Koenigin-Luise-Str. 22, D-14195 Berlin (Germany); Heinz, V [German Institute of Food Technology, p. o. box 1165, D-49601, Quackenbrueck (Germany)], E-mail: alexander.mathys@tu-berlin.de

    2008-07-15

    The mechanism of inactivation of bacterial spores by heat and pressure is still a matter of discussion. Obviously, the change of the dissociation equilibrium under pressure and temperature plays a dominant role in inactivation of microorganisms. Heat and pressure inactivation of Geobacillus. stearothermophilus spores at different initial pH-values in ACES and phosphate buffer confirmed this view. Thermal inactivation in ACES buffer at 122 deg. C resulted in higher logarithmic reductions. Contrary, after pressure treatment at 900 MPa with 80 deg. C phosphate buffer showed higher inactivation. These results indicated the different dissociation equilibrium shifts in buffer systems by heat and pressure. Due to preparation, storage and handling of highly concentrated spore suspensions the clumping and the formation of aggregates can hardly be avoided. Consequently, the impact of the agglomeration size distribution on the quantitative assessment of G. stearothermophilus spore inactivation was determined by using a three-fold dynamic optical backreflexion measurement. Two limiting cases have been discriminated in mathematical modelling: three dimensional, spherical packing for maximum spore count and two dimensional, circular packing for minimum spore count of a particular agglomerate. Thermal inactivation studies have been carried out in thin glass capillaries, where by using numerical simulations the non isothermal conditions were modelled and taken into account. It is shown that the shoulder formation often found in thermal spore inactivation can sufficiently be described by first-order inactivation kinetics when the agglomeration size is considered. In case of high pressure inactivation agglomerations could be strongly changed by high forces at compression and especially decompression phase. The physiological response of Bacillus licheniformis spores to high pressure was investigated using multiparameter flow cytometry. Spores were treated by high pressure at 150 MPa

  12. New pressure and temperature effects on bacterial spores

    International Nuclear Information System (INIS)

    Mathys, A; Knorr, D; Heinz, V

    2008-01-01

    The mechanism of inactivation of bacterial spores by heat and pressure is still a matter of discussion. Obviously, the change of the dissociation equilibrium under pressure and temperature plays a dominant role in inactivation of microorganisms. Heat and pressure inactivation of Geobacillus. stearothermophilus spores at different initial pH-values in ACES and phosphate buffer confirmed this view. Thermal inactivation in ACES buffer at 122 deg. C resulted in higher logarithmic reductions. Contrary, after pressure treatment at 900 MPa with 80 deg. C phosphate buffer showed higher inactivation. These results indicated the different dissociation equilibrium shifts in buffer systems by heat and pressure. Due to preparation, storage and handling of highly concentrated spore suspensions the clumping and the formation of aggregates can hardly be avoided. Consequently, the impact of the agglomeration size distribution on the quantitative assessment of G. stearothermophilus spore inactivation was determined by using a three-fold dynamic optical backreflexion measurement. Two limiting cases have been discriminated in mathematical modelling: three dimensional, spherical packing for maximum spore count and two dimensional, circular packing for minimum spore count of a particular agglomerate. Thermal inactivation studies have been carried out in thin glass capillaries, where by using numerical simulations the non isothermal conditions were modelled and taken into account. It is shown that the shoulder formation often found in thermal spore inactivation can sufficiently be described by first-order inactivation kinetics when the agglomeration size is considered. In case of high pressure inactivation agglomerations could be strongly changed by high forces at compression and especially decompression phase. The physiological response of Bacillus licheniformis spores to high pressure was investigated using multiparameter flow cytometry. Spores were treated by high pressure at 150 MPa

  13. Inhibiting Inosine Hydrolase and Alanine Racemase to Enhance the Germination of Bacillus anthracis Sterne Spores: Potential Spore Decontamination Strategies

    Science.gov (United States)

    2015-06-19

    decontamination strategies>> Maryline DEFEZ 1𔃼, Melissa HUNTER3J Susan WELKOS :~J Christopher COTE3 1 University Grenoble-Alpes, Grenoble, France. 1...inosine hydrolase and alanine racemase to enhance the germination of Bacillus anthracis Sterne spores potential spore decontamination strategies 5a...8217 • Accidentally in Humans • Natural reservoir is soil • Anthrax Disease Cycle: - animals infected by soilborne spores in food and water or bites from certain

  14. [Effects of exogenous nitric oxide on physiological characteristics of longan (Dimocarpus longana) seedlings under acid rain stress].

    Science.gov (United States)

    Liu, Jian-fu; Wang, Ming-yuan; Yang, Chen; Zhu, Ai-jun

    2013-08-01

    This paper studied the effects of exogenous nitric oxide donor sodium nitroprusside (SNP) on the chlorophyll content, antioxidant enzyme activities, and osmotic regulation substances of longan (Dimocarpus longana 'Fuyan') seedlings under acid rain (pH 3.0) stress. Under the acid rain stress, the seedling leaf superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and chlorophyll, soluble protein and soluble sugar contents decreased obviously, while the leaf malondialdedyde content had a remarkable increase, suggesting the toxic effect of the acid rain on the seedlings. Exogenous nitric oxide had dual nature on the physiological characteristics of longan seedlings under acid rain stress. Applying 0.1-0.5 mmol x L(-1) of SNP improved the SOD, POD and CAT activities and the chlorophyll, soluble protein and soluble sugar contents significantly, and decreased the malondialdedyde content. Low concentrations SNP reduced the oxidative damage caused by the acid rain stress, and 0.5 mmol x L(-1) of SNP had the best effect. Under the application of 0.5 mmol x L(-1) of SNP, the total chlorophyll, soluble protein, and soluble sugar contents and the SOD, POD and CAT activities increased by 76.0%, 107.0%, 216.1%, 150. 0%, 350.9% and 97.1%, respectively, and the malondialdedyde content decreased by 46.4%. It was suggested that low concentration (0.1-0.5 mmol x L(-1)) SNP could alleviate the toxic effect of acid rain stress on longan seedlings via activating the leaf antioxidant enzyme activities and reducing oxidative stress, while high concentration SNP (1.0 mmol x L(-1)) lowered the mitigation effect.

  15. Spore analysis and tetrad dissection of Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Ekwall, Karl; Thon, Genevieve

    2017-01-01

    Here we describe the processing of Schizosaccharomyces pombe spores in batches (random spore analysis) or through tetrad dissections. Spores are usually prepared from matings between haploid strains (producing zygotic asci) or from sporulating diploids (producing azygotic asci). In random spore...

  16. The sporostatic effect of cannabidiolic acid

    International Nuclear Information System (INIS)

    Farkas, J.; Andrassy, E.

    1976-01-01

    A study was undertaken to clarify whether cannabidiolic acid could be made to enhance the microbiological effect of food preservation by heat treatment or irradiation. Cannabidiolic acid was found to have a high inhibiting effect on the spores of Bacillus cereus. Its sporostatic effect is roughly equivalent to that of the antibiotics nisin and tylosin. The aqueous solution of the phytoncide of 50 μg ml -1 concentration (containing 2.5% alcohol) resisted, without a reduction of its activity, a heat treatment of 30 min at 110 deg C. Its activity was reduced by only 15% upon treatment with 400 krad. Hereafter the influence of cannabidiolic acid, added to the brine of canned peas at a concentration of 10 μgml -1 , was studied on samples exposed to treatment with 500 krad or given a heat treatment equivalent to F 0 =4.8. In these combination treatments cannabidiolic acid added at the above concentration proved to be ineffective. On investigating the cause of this phenomenon, cannabidiolic acid was found to react with protein of peas prior to irradiation or heat treatment, or in an early phase of treatment loosing thereby its microbiological effect. On the other hand, since cannabidiolic acid cannot react with proteins denatured by heat, it was found active in a sterilized nutrient medium containing denatured protein. (F.J.)

  17. VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture

    NARCIS (Netherlands)

    Wang, Fengfeng; Dijksterhuis, Jan; Wyatt, Timon; Wösten, Han A B; Bleichrodt, Robert-Jan

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger

  18. Surface properties of heat-induced soluble soy protein aggregates of different molecular masses.

    Science.gov (United States)

    Guo, Fengxian; Xiong, Youling L; Qin, Fang; Jian, Huajun; Huang, Xiaolin; Chen, Jie

    2015-02-01

    Suspensions (2% and 5%, w/v) of soy protein isolate (SPI) were heated at 80, 90, or 100 °C for different time periods to produce soluble aggregates of different molecular sizes to investigate the relationship between particle size and surface properties (emulsions and foams). Soluble aggregates generated in these model systems were characterized by gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Heat treatment increased surface hydrophobicity, induced SPI aggregation via hydrophobic interaction and disulfide bonds, and formed soluble aggregates of different sizes. Heating of 5% SPI always promoted large-size aggregate (LA; >1000 kDa) formation irrespective of temperature, whereas the aggregate size distribution in 2% SPI was temperature dependent: the LA fraction progressively rose with temperature (80→90→100 °C), corresponding to the attenuation of medium-size aggregates (MA; 670 to 1000 kDa) initially abundant at 80 °C. Heated SPI with abundant LA (>50%) promoted foam stability. LA also exhibited excellent emulsifying activity and stabilized emulsions by promoting the formation of small oil droplets covered with a thick interfacial protein layer. However, despite a similar influence on emulsion stability, MA enhanced foaming capacity but were less capable of stabilizing emulsions than LA. The functionality variation between heated SPI samples is clearly related to the distribution of aggregates that differ in molecular size and surface activity. The findings may encourage further research to develop functional SPI aggregates for various commercial applications. © 2015 Institute of Food Technologists®

  19. Palatability of water-soluble extracts of protein sources and replacement of fishmeal by a selected mixture of protein sources for juvenile turbot ( Scophthalmus maximus)

    Science.gov (United States)

    Dong, Chun; He, Gen; Mai, Kangsen; Zhou, Huihui; Xu, Wei

    2016-06-01

    Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. The present study was conducted to investigate the palatability of water-soluble extracts from single protein source (single extract pellets) and the mixture of these extracts with different proportions (blended extract pellets) in juvenile turbot ( Scophthalmus maximus). Then according to the palatability of blended extract pellets, an optimal mixture proportion was selected, and a new protein source made from raw protein materials with the selected proportion was formulated to replace fishmeal. Summarily, the palatability of single extract pellets for turbot was descendent from fishmeal to pet-food grade poultry by-product meal, wheat gluten meal, soybean meal, peanut meal, meat and bone meal, and corn gluten meal. Subsequently, according to the palatability of single extract pellets, 52 kinds of blended extract pellets were designed to test their palatability. The results showed that the pellets presented remarkably different palatability, and the optimal one was diet 52 (wheat gluten meal: pet-food grade poultry by-product meal: meat and bone meal: corn gluten meal = 1:6:1:2). The highest ingestion ratio (the number of pellets ingested/the number of pellets fed) was 0.73 ± 0.03, which was observed in Diet 52. Then five isonitrogenous (52% crude protein) and isocaloric (20 kJ g-1 gross energy) diets were formulated by replacing 0 (control), 35%, 50%, 65% and 80% of fishmeal with No.52 blending proportion. After a 10-weeks feeding trial, a consistent feed intake was found among all replacement treatments. Replacement level of fishmeal up to 35% did not significantly influence final body weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio of turbot. Therefore, the water-soluble extracts of protein sources play an

  20. Amplicon sequencing for the quantification of spoilage microbiota in complex foods including bacterial spores

    NARCIS (Netherlands)

    Boer, de P.; Caspers, M.; Sanders, J.W.; Kemperman, R.; Wijman, J.; Lommerse, G.; Roeselers, G.; Montijn, R.; Abee, T.; Kort, R.

    2015-01-01

    Background
    Spoilage of food products is frequently caused by bacterial spores and lactic acid bacteria. Identification of these organisms by classic cultivation methods is limited by their ability to form colonies on nutrient agar plates. In this study, we adapted and optimized 16S rRNA amplicon

  1. Cytokines: muscle protein and amino acid metabolism

    DEFF Research Database (Denmark)

    van Hall, Gerrit

    2012-01-01

    raises TNF-α and IL-6 to moderate levels, has only identified IL-6 as a potent cytokine, decreasing systemic amino acid levels and muscle protein metabolism. The marked decrease in circulatory and muscle amino acid concentrations was observed with a concomitant reduction in both the rates of muscle...... of IL-6 on the regulation of muscle protein metabolism but indirectly via IL-6 reducing amino acid availability. SUMMARY: Recent studies suggest that the best described cytokines TNF-α and IL-6 are unlikely to be the major direct mediators of muscle protein loss in inflammatory diseases. However...

  2. Dispersal of spores following a persistent random walk.

    Science.gov (United States)

    Bicout, D J; Sache, I

    2003-03-01

    A model of a persistent random walk is used to describe the transport and deposition of the spore dispersal process. In this model, the spore particle flies along straight line trajectories, with constant speed v, which are interrupted by scattering, originating from interaction of spores with the field and wind variations, which randomly change its direction. To characterize the spore dispersal gradients, we have derived analytical expressions of the deposition probability epsilon (r|v) of airborne spores as a function of the distance r from the spore source in an infinite free space and in a disk of radius R with an absorbing edge that mimics an agricultural field surrounded with fields of nonhost plants and bare land. It is found in the free space that epsilon (r|v) approximately e(-alphar/l), with alpha a function of l(d)/l, where l and l(d) are the scattering and deposition mean free paths, respectively. In the disk, however, epsilon (r|v) is an infinite series of Bessel functions and, exhibits three regimes: absorbing (Rl(d)).

  3. Effect of amino acids and amino acid derivatives on crystallization of hemoglobin and ribonuclease A

    International Nuclear Information System (INIS)

    Ito, Len; Kobayashi, Toyoaki; Shiraki, Kentaro; Yamaguchi, Hiroshi

    2008-01-01

    The effect of the addition of amino acids and amino acid derivatives on the crystallization of hemoglobin and ribonuclease A has been evaluated. The results showed that certain types of additives expand the concentration conditions in which crystals are formed. Determination of the appropriate conditions for protein crystallization remains a highly empirical process. Preventing protein aggregation is necessary for the formation of single crystals under aggregation-prone solution conditions. Because many amino acids and amino acid derivatives offer a unique combination of solubility and stabilizing properties, they open new avenues into the field of protein aggregation research. The use of amino acids and amino acid derivatives can potentially influence processes such as heat treatment and refolding reactions. The effect of the addition of several amino acids, such as lysine, and several amino acid derivatives, such as glycine ethyl ester and glycine amide, on the crystallization of equine hemoglobin and bovine pancreatic ribonuclease A has been examined. The addition of these amino acids and amino acid derivatives expanded the range of precipitant concentration in which crystals formed without aggregation. The addition of such additives appears to promote the crystallization of proteins

  4. Effect of amino acids and amino acid derivatives on crystallization of hemoglobin and ribonuclease A

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Len, E-mail: len@ksc.kwansei.ac.jp; Kobayashi, Toyoaki [School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Shiraki, Kentaro [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan); Yamaguchi, Hiroshi [School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2008-05-01

    The effect of the addition of amino acids and amino acid derivatives on the crystallization of hemoglobin and ribonuclease A has been evaluated. The results showed that certain types of additives expand the concentration conditions in which crystals are formed. Determination of the appropriate conditions for protein crystallization remains a highly empirical process. Preventing protein aggregation is necessary for the formation of single crystals under aggregation-prone solution conditions. Because many amino acids and amino acid derivatives offer a unique combination of solubility and stabilizing properties, they open new avenues into the field of protein aggregation research. The use of amino acids and amino acid derivatives can potentially influence processes such as heat treatment and refolding reactions. The effect of the addition of several amino acids, such as lysine, and several amino acid derivatives, such as glycine ethyl ester and glycine amide, on the crystallization of equine hemoglobin and bovine pancreatic ribonuclease A has been examined. The addition of these amino acids and amino acid derivatives expanded the range of precipitant concentration in which crystals formed without aggregation. The addition of such additives appears to promote the crystallization of proteins.

  5. Fifth international fungus spore conference. [Abstracts]: Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Timberlake, W.E.

    1993-04-01

    This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

  6. 40 CFR 79.67 - Glial fibrillary acidic protein assay.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Glial fibrillary acidic protein assay... Glial fibrillary acidic protein assay. (a) Purpose. Chemical-induced injury of the nervous system, i.e... paragraph (e)(3) in this section). Assays of glial fibrillary acidic protein (GFAP), the major intermediate...

  7. Comparison of hand hygiene procedures for removing Bacillus cereus spores.

    Science.gov (United States)

    Sasahara, Teppei; Hayashi, Shunji; Hosoda, Kouichi; Morisawa, Yuji; Hirai, Yoshikazu

    2014-01-01

    Bacillus cereus is a spore-forming bacterium. B. cereus occasionally causes nosocomial infections, in which hand contamination with the spores plays an important role. Therefore, hand hygiene is the most important practice for controlling nosocomial B. cereus infections. This study aimed to determine the appropriate hand hygiene procedure for removing B. cereus spores. Thirty volunteers' hands were experimentally contaminated with B. cereus spores, after which they performed 6 different hand hygiene procedures. We compared the efficacy of the procedures in removing the spores from hands. The alcohol-based hand-rubbing procedures scarcely removed them. The soap washing procedures reduced the number of spores by more than 2 log10. Extending the washing time increased the spore-removing efficacy of the washing procedures. There was no significant difference in efficacy between the use of plain soap and antiseptic soap. Handwashing with soap is appropriate for removing B. cereus spores from hands. Alcohol-based hand-rubbing is not effective.

  8. DNA repair in ultraviolet-irradiated spores of Bacillus subtilis

    International Nuclear Information System (INIS)

    Wang, T.C.V.

    1976-01-01

    It has been shown previously by others that at least two independent repair mechanisms are present in Bacillus subtilis for removing ''spore photoproduct'' from DNA of ultraviolet (254 nm)-irradiated spores after germination. One of these, designated as ''spore repair,'' is shown in this study to restore ''spore photoproduct'' to two thymine residues, leaving the DNA backbone intact at the end of the process in vivo. The circumstances under which this repair can occur and some characteristics of its energy requirements have been clarified. The second repair process is identified as excision repair, which can excise both ''spore photoproduct'' from DNA of irradiated spores and cyclobutane-type pyrimidine dimers from DNA of irradiated vegetative cells. In this study it is shown that the gene hcr 1 affects an enzyme activity for the incision step initiating this repair, while the gene hcr 42 affects a step subsequent to incision in the mechanism. In addition a third, independent repair system, termed ''germinative excision repair,'' is discovered and shown to be specific for excising only cyclobutane-type pyrimidine dimers but not ''spore photoproduct.'' This repair system is responsible for the observed high ultraviolet-resistance and temporary capacity for host cell reactivation on recently germinated spores of Bacillus subtilis HCR - strains

  9. The Role of the Electrostatic Force in Spore Adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eunhyea [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Lee, Ida [University of Tennessee, Knoxville (UTK); Tsouris, Costas [ORNL

    2010-01-01

    Electrostatic force is investigated as one of the components of the adhesion force between Bacillus thuringiensis (Bt) spores and planar surfaces. The surface potentials of a Bt spore and a mica surface are experimentally obtained using a combined atomic force microscopy (AFM)-scanning surface potential microscopy technique. On the basis of experimental information, the surface charge density of the spores is estimated at 0.03 {micro}C/cm{sup 2} at 20% relative humidity and decreases with increasing humidity. The Coulombic force is introduced for the spore-mica system (both charged, nonconductive surfaces), and an electrostatic image force is introduced to the spore-gold system because gold is electrically conductive. The Coulombic force for spore-mica is repulsive because the components are similarly charged, while the image force for the spore-gold system is attractive. The magnitude of both forces decreases with increasing humidity. The electrostatic forces are added to other force components, e.g., van der Waals and capillary forces, to obtain the adhesion force for each system. The adhesion forces measured by AFM are compared to the estimated values. It is shown that the electrostatic (Coulombic and image) forces play a significant role in the adhesion force between spores and planar surfaces.

  10. Changes in nuclear protein acetylation in u.v.-damaged human cells

    International Nuclear Information System (INIS)

    Ramanathan, B.; Smerdon, M.J.

    1986-01-01

    The levels of nuclear protein acetylation in u.v.-irradiated human fibroblasts have been investigated. Initially, we measured the levels of acetylation in total acid-soluble nuclear proteins and observed two distinct differences between the irradiated and unirradiated (control) cells. Immediately after irradiation, there is a 'wave' of protein hyperacetylation that lasts for 2-6 h, followed by a hypoacetylation phase, lasting for many hours, and the total level of acetylation does not return to that of control cells until 24-72 h after u.v. damage. Both the magnitude and duration of each phase is dependent on the dose of u.v. light used. The wave of hyperacetylation is more pronounced at low u.v. doses, while the wave of hypoacetylation is more pronounced at higher u.v. doses. Furthermore, the duration of each phase is prolonged when cells are exposed to 2 mM hydroxyurea, an agent which retards the rate of excision repair at u.v.-damaged sites. Examinations of the acetylation levels of the individual nuclear proteins indicated that acetylation of the core histones follows the same pattern observed for the total acid-soluble protein fractions. Furthermore, these were the only major proteins in the total acid-soluble fraction observed to undergo the early, rapid hyperacetylation immediately following u.v. damage. These results raise the possibility that a causal relationship exists between nuclear protein acetylation and nucleotide excision repair of DNA in human cells. (author)

  11. In vitro solubility of calcium, iron and zinc in relation to phytic acid levels in rice-based consumer products in China

    NARCIS (Netherlands)

    Liang, J.; Han, B.Z.; Nout, M.J.R.; Hamer, R.J.

    2010-01-01

    In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and

  12. Role of urea in controlling radiation-induced changes in some amino acids level and protein end products in blood serum of rats

    International Nuclear Information System (INIS)

    El-Kashef, H.S.; Saada, H.N.

    1991-01-01

    In previous studies (Helen Saada, 1982), urea could successfully act as a good radio-protector. It helps the recovery from changes induced by gamma irradiation in soluble protein contents, and percentage of protein fractions as well as some enzymatic activity. In the present study, it has been found that urea acts also as adequate radioprotector against radiation induced changes in the level of free and tied amino acids, glucosamine,free ammonia and urea concentration in the blood serum of white rats. The radioprotective role of urea was very clear on the first day after irradiation as manifested by the levels of free amino acids and protein end products (urea and ammonia). While in the case of tied amino acids, the action of urea as a radioprotector could be noticed lately, on the third post-irradiation day. The recovery from radiation hazards depended not only on the time lapse after irradiation but also on the chemical structure of the molecule which presents or constitutes the biological matter.2 tab.,1 fig

  13. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    Energy Technology Data Exchange (ETDEWEB)

    Khoza, Phindile; Antunes, Edith [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa); Chen, Ji-Yao [State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China); Nyokong, Tebello, E-mail: t.nyokong@ru.ac.za [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa)

    2013-02-15

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by {sup 1}H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: Black-Right-Pointing-Pointer A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. Black-Right-Pointing-Pointer The conjugate is water soluble even though the phthalocyanine alone is not. Black-Right-Pointing-Pointer The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. Black-Right-Pointing-Pointer Triplet quantum yields decreased for the conjugate.

  14. Uniconazole effect on endogenous hormones, proteins and proline contents of barley plants (Hordium vulgare under salinity stress (NaCl

    Directory of Open Access Journals (Sweden)

    MOHAMED A. BAKHETA

    2014-05-01

    Full Text Available Bakheta MA, Hussein MM. 2014. Uniconazole effect on endogenous hormones, proteins and proline contents of barley plants (Hordium vulgare under salinity stress (NaCl. Nusantara Bioscience 6: 39-44. Pot experiments were carried out during two growth seasons 2010 / 2011 under greenhouse conditions of the National Research Centre, Dokki, Cairo, Egypt to investigate the response of barley plants (Hordium vulgare L grown under salinity stress (2500 or 5000 ppm to spraying with solutions of uniconazole at 150 or 200 ppm. The obtained results showed that irrigation with saline solutions caused increases in the amounts of abscisic acid (ABA, crude protein, total soluble-protein and proline contents. The results showed that spraying barley plants grown under saline solutions with uniconazole increased endogenous hormone contents of ABA, cytokinins, crude protein, total soluble protein and proline but caused decreases in the amounts of endogenous indole acetic acid (IAA and gibberellic acid (GA3. High protection of abscisic acid in treating plants with uniconazole and under salt stress (interaction effect increases proline, proteins and soluble protein which has been proposed to act as compatible solutes that adjust the osmotic potential in the cytoplasm. Thus, these biochemical characters can be used as a metabolic marker in relation to salinity stress.

  15. Evaluation of soluble organic compounds generated by radiological degradation of asphalt

    International Nuclear Information System (INIS)

    Fukumoto, M.; Nishikawa, Y.; Kagawa, A.; Kawamura, K.

    2000-12-01

    The soluble organic compounds generated by radiological degradation of asphalt (γ ray) were confirmed as a part of influence of the bituminized waste degradation in the TRU waste repository. Especially, the influence of the nitrate was focused on. As a result, the concentration of the soluble organic compounds generated by radiological degradation of asphalt (10 MGy, γ ray which is correspond to absorbed dose of asphalt for 1,000,000 years) were lower (each formic acid: about 50 mg/dm 3 , acetic acid: about 30 mg/dm 3 and oxalic acid: about 2 mg/dm 3 ) than that of the formic acid, the acetic acid and the oxalic acid which Valcke et al. had shown (the influence of the organic at the solubility examination which uses Pu and Am). Moreover, the change in the concentration of TOC and the soluble organic compounds (formic acid, acetic acid and oxalic acid) is little under the existence of nitrate ion. That is, the formic acid and acetic acid which can be organic ligands were generated little by oxidative decomposition of asphalt in the process that nitrate ion becomes nitride ion by radiation. The influence of the soluble organic compounds by the radiological degradation of the asphalt (γ ray) on adsorption and solubility by the complexation of radionuclides in the performance assessment can be limited. (author)

  16. Development of bioprocess for high density cultivation yield of the probiotic Bacillus coagulans and its spores

    Directory of Open Access Journals (Sweden)

    Kavita R. Pandey

    2016-09-01

    Full Text Available Bacillus coagulans is a spore forming lactic acid bacterium. Spore forming bacteria, have been extensively studied and commercialized as probiotics. Probiotics are produced by fermentation technology. There is a limitation to biomass produced by conventional modes of fermentation. With the great demand generated by range of probiotic products, biomass is becoming very valuable for several pharmaceutical, dairy and probiotic companies. Thus, there is a need to develop high cell density cultivation processes for enhanced biomass accumulation. The bioprocess development was carried out in 6.6 L bench top lab scale fermentor. Four different cultivation strategies were employed to develop a bioprocess for higher growth and sporulation efficiencies of probiotic B. coagulans. Batch fermentation of B. coagulans yielded 18 g L-1 biomass (as against 8.0 g L-1 productivity in shake flask with 60% spore efficiency. Fed-batch cultivation was carried out for glucose, which yielded 25 g L-1 of biomass. C/N ratio was very crucial in achieving higher spore titres. Maximum biomass yield recorded was 30 g L-1, corresponding to 3.8 × 1011 cells mL-1 with 81% of cells in sporulated stage. The yield represents increment of 85 times the productivity and 158 times the spore titres relative to the highest reported values for high density cultivation of B. coagulans.

  17. Protein-membrane interaction and fatty acid transfer from intestinal fatty acid-binding protein to membranes. Support for a multistep process.

    Science.gov (United States)

    Falomir-Lockhart, Lisandro J; Laborde, Lisandro; Kahn, Peter C; Storch, Judith; Córsico, Betina

    2006-05-19

    Fatty acid transfer from intestinal fatty acid-binding protein (IFABP) to phospholipid membranes occurs during protein-membrane collisions. Electrostatic interactions involving the alpha-helical "portal" region of the protein have been shown to be of great importance. In the present study, the role of specific lysine residues in the alpha-helical region of IFABP was directly examined. A series of point mutants in rat IFABP was engineered in which the lysine positive charges in this domain were eliminated or reversed. Using a fluorescence resonance energy transfer assay, we analyzed the rates and mechanism of fatty acid transfer from wild type and mutant proteins to acceptor membranes. Most of the alpha-helical domain mutants showed slower absolute fatty acid transfer rates to zwitterionic membranes, with substitution of one of the lysines of the alpha2 helix, Lys27, resulting in a particularly dramatic decrease in the fatty acid transfer rate. Sensitivity to negatively charged phospholipid membranes was also reduced, with charge reversal mutants in the alpha2 helix the most affected. The results support the hypothesis that the portal region undergoes a conformational change during protein-membrane interaction, which leads to release of the bound fatty acid to the membrane and that the alpha2 segment is of particular importance in the establishment of charge-charge interactions between IFABP and membranes. Cross-linking experiments with a phospholipid-photoactivable reagent underscored the importance of charge-charge interactions, showing that the physical interaction between wild-type intestinal fatty acid-binding protein and phospholipid membranes is enhanced by electrostatic interactions. Protein-membrane interactions were also found to be enhanced by the presence of ligand, suggesting different collisional complex structures for holo- and apo-IFABP.

  18. Synthesis of Salt Soluble Proteins in Barley. Pulse-Labeling Study of Grain Filling in Liquid-Cultured Detached Spikes

    DEFF Research Database (Denmark)

    Giese, Nanna Henriette; Hejgaard, Jørn

    1984-01-01

    The accumulation of salt-soluble proteins in the endosperm of developing barley (Hordeum vulgare L.) grains was examined. Detached spikes of barley were cultured at different levels of nitrogen nutrition and pulse-labeled with [14C] sucrose at specific times after anthesis. Proteins were extracted...... to increased nitrogen nutrition. Two major components, β-amylase and protein Z in particular, had a synthesis profile almost identical to that of the endosperm storage protein, hordein....

  19. The role of heat resistance in thermorestoration of hydrated bacterial spores

    International Nuclear Information System (INIS)

    Friedman, Y.S.; Grecz, N.

    1973-01-01

    This study for the first time presents evidence of the distinct role played in thermorestoration by cellular determinants such as the resistance to heat and radiation, and the ionic state of spores. In the past only radiochemical determinants associated with radical annealment have been studied in hydrated systems. The basic heat resistance of spores plays a significant role in the precipitous drop in spore survival due to 0.45 Mrad radiation plus heat above 65-75 0 C for B.cereus and 75-95 0 C for B.stearothermophilus. The effect of the spores radiation resistance was not distinct except in the frozen state and at the saturation plateau of thermorestoration where the radiation resistant B.cereus showed ca. 1 log cycle higher survival than the radiation sensitive B.stearothermophilus. When spores are chemically converted into their H + and Ca ++ ionic forms, the H + spores are distinctly more responsive than Ca ++ spores to processes of radical annealment responsible for thermorestoration in hydrated spore systems. At temperatures of extensive thermorestoration of water radicals, H + spores showed higher survival than Ca ++ spores. (F.J.)

  20. Spectroscopy and viability of Bacillus subtilis spores after ultraviolet irradiation: implications for the detection of potential bacterial life on Europa.

    Science.gov (United States)

    Noell, Aaron C; Ely, Tucker; Bolser, Diana K; Darrach, Halley; Hodyss, Robert; Johnson, Paul V; Hein, Jeffrey D; Ponce, Adrian

    2015-01-01

    One of the most habitable environments in the Solar System outside of Earth may exist underneath the ice on Europa. In the near future, our best chance to look for chemical signatures of a habitable environment (or life itself) will likely be at the inhospitable icy surface. Therefore, it is important to understand the ability of organic signatures of life and life itself to persist under simulated europan surface conditions. Toward that end, this work examined the UV photolysis of Bacillus subtilis spores and their chemical marker dipicolinic acid (DPA) at temperatures and pressures relevant to Europa. In addition, inactivation curves for the spores at 100 K, 100 K covered in one micron of ice, and 298 K were measured to determine the probability for spore survival at the surface. Fourier transform infrared spectra of irradiated DPA showed a loss of carboxyl groups to CO2 as expected but unexpectedly showed significant opening of the heterocyclic ring, even for wavelengths>200 nm. Both DPA and B. subtilis spores showed identical unknown spectral bands of photoproducts after irradiation, further highlighting the importance of DPA in the photochemistry of spores. Spore survival was enhanced at 100 K by ∼5× relative to 298 K, but 99.9% of spores were still inactivated after the equivalent of ∼25 h of exposure on the europan surface.