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Sample records for ada mutant strains

  1. Mutant prevention concentrations of pradofloxacin for susceptible and mutant strains of Escherichia coli with reduced fluoroquinolone susceptibility.

    Science.gov (United States)

    Marcusson, Linda L; Komp Lindgren, Patricia; Olofsson, Sara K; Hughes, Diarmaid; Cars, Otto

    2014-10-01

    Pharmacodynamic and mutant prevention properties of the fluoroquinolone pradofloxacin (PRA) were measured against a set of 17 Escherichia coli strains carrying no, one or two known mutations conferring reduced fluoroquinolone susceptibility. The strains included susceptible wild-types, isogenic constructed mutants, isogenic selected mutants and clinical isolates. The effectiveness of PRA was determined with regard to preventing the selection of resistant mutants, using static and changing concentrations of drug. Ciprofloxacin was used as a reference drug. Minimum inhibitory concentrations (MICs) and mutant prevention concentrations (MPCs) of PRA for the susceptible wild-type strains were in the range 0.012-0.016mg/L and 0.2-0.3mg/L, respectively, giving a mean±standard deviation mutant prevention index (MPI=MPC/MIC) of 17.7±1.1. The mean MPI PRA of the 14 mutant strains was 19.2±12, and the mean MPI across all 17 strains was 18.9±10.8. In an in vitro kinetic model in which PRA was diluted with a half-life of 7h to mimic in vivo conditions, an initial concentration of PRA of 1.6-2.4mg/L (8-10× MPC), giving a PRA AUC/MPC ratio of 73-92, and a T>MPC of 21-23h was sufficient to prevent the selection of resistant mutants from the three susceptible wild-type strains. Dosing to reduce selection for antibiotic resistance in veterinary therapy has a role in reducing the reservoir of resistant mutants. We conclude that a level of dosing that prevents the selection of resistant mutants during therapy should be achievable in vivo. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  2. Revealing Differences in Metabolic Flux Distributions between a Mutant Strain and Its Parent Strain Gluconacetobacter xylinus CGMCC 2955

    Science.gov (United States)

    Liu, Miao; Yang, Xiao-Ning; Zhu, Hui-Xia; Jia, Yuan-Yuan; Jia, Shi-Ru; Piergiovanni, Luciano

    2014-01-01

    A better understanding of metabolic fluxes is important for manipulating microbial metabolism toward desired end products, or away from undesirable by-products. A mutant strain, Gluconacetobacter xylinus AX2-16, was obtained by combined chemical mutation of the parent strain (G. xylinus CGMCC 2955) using DEC (diethyl sulfate) and LiCl. The highest bacterial cellulose production for this mutant was obtained at about 11.75 g/L, which was an increase of 62% compared with that by the parent strain. In contrast, gluconic acid (the main byproduct) concentration was only 5.71 g/L for mutant strain, which was 55.7% lower than that of parent strain. Metabolic flux analysis indicated that 40.1% of the carbon source was transformed to bacterial cellulose in mutant strain, compared with 24.2% for parent strain. Only 32.7% and 4.0% of the carbon source were converted into gluconic acid and acetic acid in mutant strain, compared with 58.5% and 9.5% of that in parent strain. In addition, a higher flux of tricarboxylic acid (TCA) cycle was obtained in mutant strain (57.0%) compared with parent strain (17.0%). It was also indicated from the flux analysis that more ATP was produced in mutant strain from pentose phosphate pathway (PPP) and TCA cycle. The enzymatic activity of succinate dehydrogenase (SDH), which is one of the key enzymes in TCA cycle, was 1.65-fold higher in mutant strain than that in parent strain at the end of culture. It was further validated by the measurement of ATPase that 3.53–6.41 fold higher enzymatic activity was obtained from mutant strain compared with parent strain. PMID:24901455

  3. Revealing differences in metabolic flux distributions between a mutant strain and its parent strain Gluconacetobacter xylinus CGMCC 2955.

    Directory of Open Access Journals (Sweden)

    Cheng Zhong

    Full Text Available A better understanding of metabolic fluxes is important for manipulating microbial metabolism toward desired end products, or away from undesirable by-products. A mutant strain, Gluconacetobacter xylinus AX2-16, was obtained by combined chemical mutation of the parent strain (G. xylinus CGMCC 2955 using DEC (diethyl sulfate and LiCl. The highest bacterial cellulose production for this mutant was obtained at about 11.75 g/L, which was an increase of 62% compared with that by the parent strain. In contrast, gluconic acid (the main byproduct concentration was only 5.71 g/L for mutant strain, which was 55.7% lower than that of parent strain. Metabolic flux analysis indicated that 40.1% of the carbon source was transformed to bacterial cellulose in mutant strain, compared with 24.2% for parent strain. Only 32.7% and 4.0% of the carbon source were converted into gluconic acid and acetic acid in mutant strain, compared with 58.5% and 9.5% of that in parent strain. In addition, a higher flux of tricarboxylic acid (TCA cycle was obtained in mutant strain (57.0% compared with parent strain (17.0%. It was also indicated from the flux analysis that more ATP was produced in mutant strain from pentose phosphate pathway (PPP and TCA cycle. The enzymatic activity of succinate dehydrogenase (SDH, which is one of the key enzymes in TCA cycle, was 1.65-fold higher in mutant strain than that in parent strain at the end of culture. It was further validated by the measurement of ATPase that 3.53-6.41 fold higher enzymatic activity was obtained from mutant strain compared with parent strain.

  4. Crystal structure of penicillin G acylase from the Bro1 mutant strain of Providencia rettgeri.

    OpenAIRE

    McDonough, M. A.; Klei, H. E.; Kelly, J. A.

    1999-01-01

    Penicillin G acylase is an important enzyme in the commercial production of semisynthetic penicillins used to combat bacterial infections. Mutant strains of Providencia rettgeri were generated from wild-type cultures subjected to nutritional selective pressure. One such mutant, Bro1, was able to use 6-bromohexanamide as its sole nitrogen source. Penicillin acylase from the Bro1 strain exhibited an altered substrate specificity consistent with the ability of the mutant to process 6-bromohexana...

  5. Comparative metabolic flux analysis of an Ashbya gossypii wild type strain and a high riboflavin-producing mutant strain.

    Science.gov (United States)

    Jeong, Bo-Young; Wittmann, Christoph; Kato, Tatsuya; Park, Enoch Y

    2015-01-01

    In the present study, we analyzed the central metabolic pathway of an Ashbya gossypii wild type strain and a riboflavin over-producing mutant strain developed in a previous study in order to characterize the riboflavin over-production pathway. (13)C-Metabolic flux analysis ((13)C-MFA) was carried out in both strains, and the resulting data were fit to a steady-state flux isotopomer model using OpenFLUX. Flux to pentose-5-phosphate (P5P) via the pentose phosphate pathway (PPP) was 9% higher in the mutant strain compared to the wild type strain. The flux from purine synthesis to riboflavin in the mutant strain was 1.6%, while that of the wild type strain was only 0.1%, a 16-fold difference. In addition, the flux from the cytoplasmic pyruvate pool to the extracellular metabolites, pyruvate, lactate, and alanine, was 2-fold higher in the mutant strain compared to the wild type strain. This result demonstrates that increased guanosine triphosphate (GTP) flux through the PPP and purine synthesis pathway (PSP) increased riboflavin production in the mutant strain. The present study provides the first insight into metabolic flux through the central carbon pathway in A. gossypii and sets the foundation for development of a quantitative and functional model of the A. gossypii metabolic network.

  6. Antibodies with higher bactericidal activity induced by a Neisseria gonorrhoeae Rmp deletion mutant strain.

    Directory of Open Access Journals (Sweden)

    Guocai Li

    Full Text Available Neisseria gonorrhoeae (N. gonorrhoeae outer membrane protein reduction modifiable protein (Rmp has strong immunogenicity. However, anti-Rmp antibodies block rather than preserve the antibacterial effects of protective antibodies, which hampers the development of vaccines for gonococcal infections. We herein constructed an Rmp deletion mutant strain of N. gonorrhoeae by gene homologous recombination. The 261-460 nucleotide residues of Rmp gene amplified from N. gonorrhoeae WHO-A strain were replaced with a kanamycin-resistant Kan gene amplified from pET-28a. The resultant hybridized DNA was transformed into N. gonorrhoeae WHO-A strain. PCR was used to screen the colonies in which wild-type Rmp gene was replaced with a mutant gene fragment. Western blotting revealed that the Rmp deletion mutant strain did not express Rmp protein. Rmp deletion did not alter the morphological and Gram staining properties of the mutant strain that grew slightly more slowly than the wild-type one. Rmp gene mutated stably throughout 25 generations of passage. Antibody-mediated complement-dependent cytotoxicity assay indicated that the antibodies induced by the mutant strain had evidently higher bactericidal activities than those induced by the wild-type strain. Further modification of the Rmp deletion mutant strain is still required in the development of novel live attenuated vaccines for gonorrhea by Opa genes deletion or screening of phenotypic variant strains that do not express Opa proteins.

  7. Antibodies with higher bactericidal activity induced by a Neisseria gonorrhoeae Rmp deletion mutant strain.

    Science.gov (United States)

    Li, Guocai; Xie, Rushan; Zhu, Xiaoping; Mao, Yanli; Liu, Shuangxi; Jiao, Hongmei; Yan, Hua; Xiong, Kun; Ji, Mingchun

    2014-01-01

    Neisseria gonorrhoeae (N. gonorrhoeae) outer membrane protein reduction modifiable protein (Rmp) has strong immunogenicity. However, anti-Rmp antibodies block rather than preserve the antibacterial effects of protective antibodies, which hampers the development of vaccines for gonococcal infections. We herein constructed an Rmp deletion mutant strain of N. gonorrhoeae by gene homologous recombination. The 261-460 nucleotide residues of Rmp gene amplified from N. gonorrhoeae WHO-A strain were replaced with a kanamycin-resistant Kan gene amplified from pET-28a. The resultant hybridized DNA was transformed into N. gonorrhoeae WHO-A strain. PCR was used to screen the colonies in which wild-type Rmp gene was replaced with a mutant gene fragment. Western blotting revealed that the Rmp deletion mutant strain did not express Rmp protein. Rmp deletion did not alter the morphological and Gram staining properties of the mutant strain that grew slightly more slowly than the wild-type one. Rmp gene mutated stably throughout 25 generations of passage. Antibody-mediated complement-dependent cytotoxicity assay indicated that the antibodies induced by the mutant strain had evidently higher bactericidal activities than those induced by the wild-type strain. Further modification of the Rmp deletion mutant strain is still required in the development of novel live attenuated vaccines for gonorrhea by Opa genes deletion or screening of phenotypic variant strains that do not express Opa proteins.

  8. [Composition of cell walls of 2 mutant strains of Streptomyces chrysomallus].

    Science.gov (United States)

    Zaretskaia, M Sh; Nefelova, M V; Baratova, L A; Polin, A N

    1984-12-01

    The cell walls and peptidoglycans of two mutant strains, Streptomyces chrysomallus var. carotenoides and Streptomyces chrysomallus var. macrotetrolidi, were studied. The strains are organisms producing carotenes and antibiotics of the macrotetrolide group. By the qualitative composition of the peptidoglycans the mutants belong to Streptomyces and are similar. Their glycan portion consists of equimolar quantities of N-acetyl glucosamine and muramic acid. The peptide subunit is presented by glutamic acid, L, L-diaminopimelic acid, glycine and alanine. The molar ratio of alanine is 1.2-1.3. The mutant strains differ in the content of carbohydrates, total phosphorus and phosphorus belonging to teichoic acids. Teichoic acids of the cell walls of the both strains are of the ribitolhosphate nature. The cell walls of the mutants contain polysaccharides differing from teichoic acids and consisting of glucose, galactose, arabinose and fucose. The influence of the cell wall composition of the mutant strains on their morphology and metabolism and comparison of the data relative to the mutant strains with those relative to the starting strain are discussed.

  9. Induction, isolation, and characterization of aspergillus niger mutant strains producing elevated levels of beta-galactosidase.

    OpenAIRE

    1981-01-01

    An Aspergillus niger mutant strain, VTT-D-80144, with an improvement of three- to fourfold in the production of extracellular beta-galactosidase was isolated after mutagenesis. The production of beta-galactosidase by this mutant was unaffected by fermentor size, and the enzyme was also suitable for immobilization.

  10. Ada COCOMO and the Ada Process Model

    Science.gov (United States)

    1989-01-01

    language, the use of incremental development, and the use of the Ada process model capitalizing on the strengths of Ada to improve the efficiency of software...development. This paper presents the portions of the revised Ada COCOMO dealing with the effects of Ada and the Ada process model . The remainder of...this section of the paper discusses the objectives of Ada COCOMO. Section 2 describes the Ada Process Model and its overall effects on software

  11. Comparison of mutant and parent strains of Clostridium acetobutylicum: butyrate uptake at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Soni, B.K. [Institute of Gas Technology, 1700 S. Mount Prospect Road, Des Plaines, IL 60018 (United States); Jain, M.K. [MBI International, P.O. Box 27609, 3900 Collins Road, Lansing, MI 48909 (United States)

    1997-10-01

    A high butanol producing mutant strain of Clostridium acetobutylicum ATCC 4259 was obtained by chemical mutagenesis. Both mutant and parent strains were evaluated for butyrate uptake using the culture effluents of solventogenic fermentor-2 of the two-fermentor continuous system. Batch incubation of fermentor-2 culture effluents at 37 C indicated lower butyrate uptake rates for mutant and parent strain, at 0.05 and 0.03 g l{sup -1} h{sup -1}, respectively. Increased butyrate uptake rates of 0.33 and 0.26 g l{sup -1} h{sup -1} for mutant and parent strain, respectively, were observed when effluents were batch incubated at lower temperature of 30 C. Butyrate conversion efficiency, at 5 {+-} 0.1 g l{sup -1} of externally added butyrate, were 98.8% and 96.9% for mutant and parent strain, respectively. Butyrate up to the externally added concentration of 11.4 g l{sup -1} did not inhibit butyrate uptake. The maximum butyrate consumption at a slightly reduced uptake rate was seen at 10.2 g l{sup -1} butyrate concentration at 27 C. Based on the results under different temperatures, the electron flow pattern has been computed and the mechanism for butyrate uptake has been hypothesized. (orig.) With 6 figs., 4 tabs., 26 refs.

  12. Phosphoregulation of an Inner Dynein Arm Complex in Chlamydomonas reinhardtii Is Altered in Phototactic Mutant Strains

    Science.gov (United States)

    King, Stephen J.; Dutcher, Susan K.

    1997-01-01

    To gain a further understanding of axonemal dynein regulation, mutant strains of Chlamydomonas reinhardtii that had defects in both phototactic behavior and flagellar motility were identified and characterized. ptm1, ptm2, and ptm3 mutant strains exhibited motility phenotypes that resembled those of known inner dynein arm region mutant strains, but did not have biochemical or genetic phenotypes characteristic of other inner dynein arm mutations. Three other mutant strains had defects in the f class of inner dynein arms. Dynein extracts from the pf9-4 strain were missing the entire f complex. Strains with mutations in pf9/ida1, ida2, or ida3 failed to assemble the f dynein complex and did not exhibit phototactic behavior. Fractionated dynein from mia1-1 and mia2-1 axonemes exhibited a novel f class inner dynein arm biochemical phenotype; the 138-kD f intermediate chain was present in altered phosphorylation forms. In vitro axonemal dynein activity was reduced by the mia1-1 and mia2-1 mutations. The addition of kinase inhibitor restored axonemal dynein activity concomitant with the dephosphorylation of the 138-kD f intermediate chain. Dynein extracts from uni1-1 axonemes, which specifically assemble only one of the two flagella, contained relatively high levels of the altered phosphorylation forms of the 138-kD intermediate chain. We suggest that the f dynein complex may be phosphoregulated asymmetrically between the two flagella to achieve phototactic turning. PMID:9008712

  13. Infection of the ferret stomach by isogenic flagellar mutant strains of Helicobacter mustelae.

    OpenAIRE

    Andrutis, K A; Fox, J G; Schauer, D B; Marini, R P; Li, X.; L. Yan; Josenhans, C; Suerbaum, S

    1997-01-01

    Helicobacter mustelae, like Helicobacter pylori, possesses two flagellin proteins, FlaA and FlaB. Isogenic mutant strains of H. mustelae have been constructed by disruption of the flaA or flaB gene with a kanamycin resistance cassette or by introduction of both a kanamycin and a chloramphenicol resistance gene to produce a double mutant. To determine whether one or both flagellin proteins are necessary for colonization and persistence of infection with H. mustelae, 19 ferrets, specific pathog...

  14. Construction of a doramectin producer mutant from an avermectin-overproducing industrial strain of Streptomyces avermitilis.

    Science.gov (United States)

    Zhao, Xuejin; Wang, Yuanxin; Wang, Shiwei; Chen, Zhi; Wen, Ying; Song, Yuan

    2009-12-01

    The avermectin analogue doramectin (CHC-B1), which is produced in mutants that have an altered biosynthesis pathway of avermectin, is one of the most effective agricultural pesticides and antiparasitics. We report here the construction of a bkdF olmA double-deletion mutant lacking one of the branched-chain alpha-keto acid dehydrogenase encoding genes (bkdF) and the oligomycin PKS encoding gene cluster (olmA) in Streptomyces avermitilis 76-05. We then characterized the production of various antibiotics in cultures of the deletion mutant. In a fermentation medium supplemented with cyclohexanecarboxylic acid, this double mutant produced doramectin and its analogues but no oligomycin. The mutant proved to be genetically stable, without any antibiotic resistance markers inserted into its chromosome, and could potentially become an industrial doramectin-producing strain after further improvement.

  15. Tryptophan provision by dietary supplementation of a Bacillus subtilis mutant strain in piglets

    DEFF Research Database (Denmark)

    Torres-Pitarch, A; Nielsen, B.; Canibe, Nuria

    2015-01-01

    Supplementing Bacillus (B.) subtilis mutants selected to overproduce a specific amino acid (AA) may be an alternative method to provide essential AA in pig diets. Two experiments on a B. subtilis strain selected to overproduce Trp were conducted using 8-kg pigs fed Trp-deficient diets for 20 d. B...... to counterbalance the Trp deficiency in any of the two experiments. No effect of B. subtilis supplementation to piglet diets was observed on the plasma AA profile. In conclusion, this mutant strain of B. subtilis was not able to compensate a Trp deficiency in the tested doses....

  16. Global carbon utilization profiles of wild-type, mutant, and transformant strains of Hypocrea jecorina.

    Science.gov (United States)

    Druzhinina, Irina S; Schmoll, Monika; Seiboth, Bernhard; Kubicek, Christian P

    2006-03-01

    The ascomycete Hypocrea jecorina (Trichoderma reesei), an industrial producer of cellulases and hemicellulases, can efficiently degrade plant polysaccharides. However, the catabolic pathways for the resulting monomers and their relationship to enzyme induction are not well known. Here we used the Biolog Phenotype MicroArrays technique to evaluate the growth of H. jecorina on 95 carbon sources. For this purpose, we compared several wild-type isolates, mutants producing different amounts of cellulases, and strains transformed with a heterologous antibiotic resistance marker gene. The wild-type isolates and transformed strains had the highest variation in growth patterns on individual carbon sources. The cellulase mutants were relatively similar to their parental strains. Both in the mutant and in the transformed strains, the most significant changes occurred in utilization of xylitol, erythritol, D-sorbitol, D-ribose, D-galactose, L-arabinose, N-acetyl-D-glucosamine, maltotriose, and beta-methyl-glucoside. Increased production of cellulases was negatively correlated with the ability to grow on gamma-aminobutyrate, adonitol, and 2-ketogluconate; and positively correlated with that on d-sorbitol and saccharic acid. The reproducibility, relative simplicity, and high resolution (+/-10% of increase in mycelial density) of the phenotypic microarrays make them a useful tool for the characterization of mutant and transformed strains and for a global analysis of gene function.

  17. Sexual behavior of mutant strains of the medfly Ceratitis capitata (Diptera: Tephritidae

    Directory of Open Access Journals (Sweden)

    R.D Briceño

    2003-09-01

    Full Text Available Males of the mutant strains (blind, vestigal-winged of the Mediterranean fruit fly (medfly, Ceratits capitata (Wiedmann showed differences in behavior compared with control (mass-reared males. Mutant males made fewer mating attempts and achieved fewer matings than control males. Vestigal-winged females copulated less frequently with both mutants. Blind males climbed rather than jumped onto females and copulated in very low numbers compared with control and vestigal males. Blind females copulated normally with control, males and in very low numbers with both types of mutant malesMachos mutantes (ciegos, alas vestigiales de la mosca del mediterráneo Ceratitis capitata (Wiedmann mostraron diferencias en conducta comparados con los machos testigo (cría masiva. Los machos mutantes, realizaron menos intentos por aparearse y lograron menos apareamientos que los machos testigo. Las hembras con alas vestigiales, copularon menos con ambas clases de mutantes. Los machos ciegos, subieron en lugar de saltar sobre las hembras y copularon en números muy bajos comparados con los machos testigo y con los de alas vestigiales. Las hembras ciegas, copularon de forma normal con los machos testigo y en números muy bajos con ambos tipos de machos mutantes

  18. Synthesis of poly(3-hydroxyalkanoates) by mutant and recombinant Pseudomonas strains

    NARCIS (Netherlands)

    Huisman, Gjalt W.; WONINK, E; DEKONING, G; Preusting, Hans; Witholt, Bernard

    1992-01-01

    We have studied the accumulation kinetics and physical characteristics of the poly(3-hydroxyalkanoates) (PHAs) formed by several Pseudomonas strains, mutants and recombinants. Although PHA synthesis generally begins only after an essential nutrient such as N, P, S or Mg becomes limiting, we have ide

  19. Characterization and increment of amylase production in mutant strains of Iranian native Bacillus licheniformis

    Directory of Open Access Journals (Sweden)

    Mohsen Mobini-Dehkordi

    2017-03-01

    Results: In this study, two interesting mutant strains were isolated and named B.L.2.M.1 and B.L.2.M.2. Mutations caused many changes in bacteria such as cell growth speed and enzyme production content. Differences in cell growth, production of amylase and other characters were significant at 0.05 level (Pvalue

  20. A mutant ('lab strain') of the hyperthermophilic archaeon Pyrococcus furiosus, lacking flagella, has unusual growth physiology.

    Science.gov (United States)

    Lewis, Derrick L; Notey, Jaspreet S; Chandrayan, Sanjeev K; Loder, Andrew J; Lipscomb, Gina L; Adams, Michael W W; Kelly, Robert M

    2015-03-01

    A mutant ('lab strain') of the hyperthermophilic archaeon Pyrococcus furiosus DSM3638 exhibited an extended exponential phase and atypical cell aggregation behavior. Genomic DNA from the mutant culture was sequenced and compared to wild-type (WT) DSM3638, revealing 145 genes with one or more insertions, deletions, or substitutions (12 silent, 33 amino acid substitutions, and 100 frame shifts). Approximately, half of the mutated genes were transposases or hypothetical proteins. The WT transcriptome revealed numerous changes in amino acid and pyrimidine biosynthesis pathways coincidental with growth phase transitions, unlike the mutant whose transcriptome reflected the observed prolonged exponential phase. Targeted gene deletions, based on frame-shifted ORFs in the mutant genome, in a genetically tractable strain of P. furiosus (COM1) could not generate the extended exponential phase behavior observed for the mutant. For example, a putative radical SAM family protein (PF2064) was the most highly up-regulated ORF (>25-fold) in the WT between exponential and stationary phase, although this ORF was unresponsive in the mutant; deletion of this gene in P. furiosus COM1 resulted in no apparent phenotype. On the other hand, frame-shifting mutations in the mutant genome negatively impacted transcription of a flagellar biosynthesis operon (PF0329-PF0338).Consequently, cells in the mutant culture lacked flagella and, unlike the WT, showed minimal evidence of exopolysaccharide-based cell aggregation in post-exponential phase. Electron microscopy of PF0331-PF0337 deletions in P. furiosus COM1 showed that absence of flagella impacted normal cell aggregation behavior and, furthermore, indicated that flagella play a key role, beyond motility, in the growth physiology of P. furiosus.

  1. [Ribosome engineering of streptomyces sp. FJ3 from Three Gorges reservoir area and metabolic product of the selected mutant strain].

    Science.gov (United States)

    Hai, Le; Huang, Yuqi; Liao, Guojian; Hu, Changhua

    2011-07-01

    To explore new resource from inactive actinomycete strains, we screened resistant mutant strains by ribosome engineering, and analyzed the products derived from the selected mutant strains. Three Gorges reservoir area-derived actinomycete strains including BD20, FJ3, WZ20 and FJ5 were used as initial strains, which showed no-antibacterial activities. The streptomycin-resistant (str(R)) mutants and rifampicin-resistant (rif(R)) mutants were screened by single colony isolation on streptomycin-containing plates and rifampicin-containing plates according to the method for obtaining drug-resistant mutants in ribosome engineering. The four initial strains and their str(R)-mutants and rif(R)-mutants were fermented in a liquid medium with the same composition. Mutants with anti-Staphylococcus aureus activity were obtained by paper chromatography. The components of fermentation broth were analyzed by high performance liquid chromatography (HPLC) and high performance liquid chromatography-mass spectrometry (LC-MS). Furthermore, FJ3 strain was identified by 16S rDNA and morphology. The minimal inhibitory concentration (MIC) of streptomycin and rifampicin for FJ3 was: 0.5 microg/mL and 110 microg/mL, respectively. Twenty-four strR-mutant strains and 20 rif(R)-mutant strains of FJ3 mutant strains were selected for bioassay. The result of the antibacterial activity screening demonstrated that six strains inhibited bacteria. Two strains (FJ3-2 and FJ3-6) were screened from the streptomycin-resistance mutants of inactive strain FJ3. The result of bioassay showed that the fermentation broth of FJ3-2 and FJ3-6 exhibited obvious anti-Staphylococcus aureus activity. The assay of paper chromatography showed that the active substance may be nucleic acid class antibiotic via using solvent system Doskochilova. Moreover, the results of HPLC and LC-MS exhibited that this substance may be thiolutin. Ribosome engineering for changing the secondary metabolic function of the inactive wild

  2. Construction and characterization of a H19 epitope point mutant of MDV CVI988/Rispens strain.

    Science.gov (United States)

    Cui, Z; Qin, A; Lee, L F; Wu, P; Kung, H J

    1999-01-01

    A recombinant virus, CVI/rpp38, was developed from the Marek's disease virus (MDV) CVI988/Rispens vaccine strain. This recombinant was obtained by transfection of CVI988/Rispens-infected chick embryo fibroblasts (CEFs) with plasmid pHA25 DNA containing pp38 gene from GA strain of MDV. Monoclonal antibody (MAb) H19 which reacts with pp38 from GA but not with that from CVI988 was used to screen for recombinant viruses in transfected cell culture plates by immunofluorescent assay (IFA). A positive plaque was isolated, propagated, and purified from cell-free virus particles after sonication of infected CEFs. The mutant CVI/rpp38 was not only reactive with MAb H19 in IFA but also in immunoprecipitation. A 38 kDa protein was immunoprecipitated from the CVI/rpp38 mutant virus but not from parental CVI988 virus. DNA sequence of the mutant virus showed a substitution of G at position 320 by a resulting in a change of an amino acid residue from arginine to glutamine. Comparison of nucleotide sequence of pp38 from strains GA, Md5 and Md11/75c/R2 and CVI988 revealed change to glutamine in this position. The result of this study provides a direct evidence for the location of the identified H19 epitope in pp38. This mutant is potentially useful to further explore the biological function of pp38 and its H19 epitope.

  3. Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis

    Institute of Scientific and Technical Information of China (English)

    Cheng-gang CAI; Bing-gan LOU; Xiao-dong ZHENG

    2008-01-01

    A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% (v/v), age of inoculum of 16 h, and cultivation at 23 ℃. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2,therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production.

  4. Production of a thermal stress resistant mutant Euglena gracilis strain using Fe-ion beam irradiation.

    Science.gov (United States)

    Yamada, Koji; Kazama, Yusuke; Mitra, Sharbanee; Marukawa, Yuka; Arashida, Ryo; Abe, Tomoko; Ishikawa, Takahiro; Suzuki, Kengo

    2016-08-01

    Euglena gracilis is a common phytoplankton species, which also has motile flagellate characteristics. Recent research and development has enabled the industrial use of E. gracilis and selective breeding of this species is expected to further expand its application. However, the production of E. gracilis nuclear mutants is difficult because of the robustness of its genome. To establish an efficient mutation induction procedure for E. gracilis, we employed Fe-ion beam irradiation in the RIKEN RI beam factory. A decrease in the survival rate was observed with the increase in irradiation dose, and the upper limit used for E. gracilis selective breeding was around 50 Gy. For a practical trial of Fe-ion irradiation, we conducted a screening to isolate high-temperature-tolerant mutants. The screening yielded mutants that proliferated faster than the wild-type strain at 32 °C. Our results demonstrate the effectiveness of heavy-ion irradiation on E. gracilis selective breeding.

  5. A Mutant Strain of a Surfactant-Producing Bacterium with Increased Emulsification Activity

    Institute of Scientific and Technical Information of China (English)

    Liu Qingmei; Yao Jianming; Pan Renrui; Yu Zengliang

    2005-01-01

    As reported in this paper, a strain of oil-degrading bacterium Sp- 5- 3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery(MEOR). The aim of our study was to generate a mutant using low energy N+ beam implantation. With 10 keV of energy and 5.2 × 10TM N+/cm2 of dose - the optimum condition, a mutant,S - 34, was obtained, which had nearly a 5-fold higher surface and a 13-fold higher of emulsification activity than the wild type. The surface activity was measured by two methods, namely, a surface tension measuring instrument and a recording of the repulsive circle of the oil film; the emulsification activity was scaled through measuring the separating time of the oil-fermentation mixture. The metabolic acid was determined as methane by means of gas chromatography.

  6. Production of cellulase using a mutant strain of trichoderma reesei growing on lactose in batch culture

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, B.K. (Indian Inst. of Tech., New Delhi (India). Biochemical Engineering Research Centre); Sahai, V. (Indian Inst. of Tech., New Delhi (India). Biochemical Engineering Research Centre)

    1993-05-01

    The production of cellulases in batch culture was studied using a mutant strain of Trichoderma reesei C-5 growing on lactose. Growth kinetic parameters on 2% lactose were studied and the comparative results for growth and enzyme productivities at two different lactose levels are discussed. The cellulase synthesis rate depended on the lactose concentration in the medium. Although growth was favoured at a higher lactose level, the volumetric enzyme productivity did not increase in proportion and the specific enzyme productivity decreased to a certain extent, indicating that partial catabolic inhibition at higher lactose concentrations may be possible. However, it was noted that the mutant strain was highly derepressed and capable of synthesising active cellulases on lactose. (orig.)

  7. Regulation of nitrogen metabolism is altered in a glnB mutant strain of Rhizobium leguminosarum.

    Science.gov (United States)

    Amar, M; Patriarca, E J; Manco, G; Bernard, P; Riccio, A; Lamberti, A; Defez, R; Iaccarino, M

    1994-02-01

    We isolated a Rhizobium leguminosarum mutant strain altered in the glnB gene. This event, which has never been described in the Rhizobiaceae, is rare in comparison to mutants isolated in the contiguous gene, glnA. The glnB mutation removes the glnBA promoter but in vivo does not prevent glnA expression from its own promoter, which is not nitrogen regulated. The glnB mutant strain does not grow on nitrate as a sole nitrogen source and it is Nod+, Fix+. Two -24/-12 promoters, for the glnII and glnBA genes, are constitutively expressed in the glnB mutant, while two -35/-10-like promoters for glnA and ntrBC are unaffected. We propose that the glnB gene product, the PII protein, plays a negative role in the ability of NtrC to activate transcription from its target promoters and a positive role in the mechanism of nitrate utilization.

  8. Isolation, characterization and long term preservation of mutant strains of Xanthophyllomyces dendrorhous.

    Science.gov (United States)

    Baeza, Marcelo; Retamales, Patricio; Sepúlveda, Dionisia; Lodato, Patricia; Jiménez, Antonio; Cifuentes, Víctor

    2009-04-01

    The yeast Xanthophyllomyces dendrorhous is biotechnologically important due to its ability to produce the pigment astaxanthin, but is poorly understood at the genetic level. This is mainly because its preservation is difficult and many of the mutants obtained are unstable. The objectives of the present work were (i) the mutagenesis X. dendrorhous and, (ii) isolation of mutants with auxotrophic markers suitable for genetic studies of the carotenogenesis pathway and sexual cycle. Additionally, two kinds of preservation methods at the laboratory level were tested for the storage of strains. A collection of X. dendrorhous mutants affected in the production of carotenoid pigments or development of sexual structures and auxotrophic requirements were isolated by treatment with N-methyl-N'-nitro-N-nitrosoguanidine and the antibiotic nystatin. From a detailed analysis about the requirements of auxotrophic mutants the ARG7, ARG3 and PRO3 loci can be defined in this yeast. Among the methods assayed for the long-term preservation of X. dendrorhous strains, the dehydrated gelatin drop method showed the highest recovery of viable yeast after storage for 65 months. No changes in auxotrophic properties and in macro or micro morphology were observed after applying the latter method.

  9. Butyric acid fermentation from pre-treated wheat straw by a mutant clostridium tyrobutyricum strain

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Baumann, Ivan; Westermann, Peter;

    ’s platform for a variety of products for industrial use. Butyric acid is considered as a potential chemical building-block for the production of chemicals for e.g. polymeric compounds and the aim of this work was to develop a suitable and robust strain of Clostridium tyrobutyricum that produces less acetic...... acid (higher selectivity), has a higher yield and a higher productivity of butyric acid from pre-treated lignocellulosic biomass. Pre-treated wheat straw was used as the main carbon source. After one year of serial adaptation and selection a mutant strain of C. tyrobutyricum was developed. This new...

  10. Cytological characterization of an Aspergillus Nidulans mutant from a strain with chromosomic duplication.

    Science.gov (United States)

    Giancoli, Agata Cristiane Huppert; de Azevedo, João Lúcio; Pizzirani-Kleiner, Aline Aparecida

    2010-01-01

    A development mutant, named V103, was obtained spontaneously from the A strain of A. nidulans. The A strain contains a duplicated segment of chromosome I that has undergone translocation to chromosome II (I II). It is mitotically unstable and generates phenotypically deteriorated types, some with enhanced stability. The deteriorated variants of A. nidulans show abnormal development, exhibiting slower colony growth, variations in colony pigmentation and changes in conidiophore structure. The alterations observed in the conidiophore include fewer metulae and phialides, further elongation and ramification of these structures, delayed nuclear migration and the presence of secondary conidiophores.

  11. Cytological characterization of an Aspergillus nidulans mutant from a strain with chromosomic duplication

    Directory of Open Access Journals (Sweden)

    Ágata Cristiane Huppert Giancoli

    2010-03-01

    Full Text Available A development mutant, named V103, was obtained spontaneously from the A strain of A. nidulans. The A strain contains a duplicated segment of chromosome I that has undergone translocation to chromosome II (I → II. It is mitotically unstable and generates phenotypically deteriorated types, some with enhanced stability. The deteriorated variants of A. nidulans show abnormal development, exhibiting slower colony growth, variations in colony pigmentation and changes in conidiophore structure. The alterations observed in the conidiophore include fewer metulae and phialides, further elongation and ramification of these structures, delayed nuclear migration and the presence of secondary conidiophores.

  12. Isolation and characterization of the E. coli membrane protein production strain Mutant56(DE3)

    DEFF Research Database (Denmark)

    Baumgarten, Thomas; Schlegel, Susan; Wagner, Samuel

    2017-01-01

    Membrane protein production is usually toxic to E. coli. However, using genetic screens strains can be isolated in which the toxicity of membrane protein production is reduced, thereby improving production yields. Best known examples are the C41(DE3) and C43(DE3) strains, which are both derived...... from the T7 RNA polymerase (P)-based BL21(DE3) protein production strain. In C41(DE3) and C43(DE3) mutations lowering t7rnap expression levels result in strongly reduced T7 RNAP accumulation levels. As a consequence membrane protein production stress is alleviated in the C41(DE3) and C43(DE3) strains......, thereby increasing membrane protein yields. Here, we isolated Mutant56(DE3) from BL21(DE3) using a genetic screen designed to isolate BL21(DE3)-derived strains with mutations alleviating membrane protein production stress other than the ones in C41(DE3) and C43(DE3). The defining mutation of Mutant56(DE3...

  13. Coenzyme Q10 production in a 150-l reactor by a mutant strain of Rhodobacter sphaeroides.

    Science.gov (United States)

    Kien, Nguyen Ba; Kong, In-Soo; Lee, Min-Gyu; Kim, Joong Kyun

    2010-05-01

    For the commercial production of CoQ(10), batch-type fermentations were attempted in a 150-l fermenter using a mutant strain of R. sphaeroides. Optimum temperature and initial aeration rate were found to be 30 degrees C and 2 vvm, respectively. Under optimum fermentation conditions, the maximum value of specific CoQ(10) content was achieved reproducibly as 6.34 mg/g DCW after 24 h, with 3.02 g/l of DCW. During the fermentation, aeration shift (from the adequate aeration at the early growth phase to the limited aeration in active cellular metabolism) was a key factor in CoQ(10) production for scale-up. A higher value of the specific CoQ(10) content (8.12 mg/g DCW) was achieved in fed-batch fermentation and comparable to those produced by the pilot-scale fed-batch fermentations of A. tumefaciens, which indicated that the mutant strain of R. sphaeroides used in this study was a potential high CoQ(10) producer. This is the first detailed study to demonstrate a pilot-scale production of CoQ(10) using a mutant strain of R. sphaeroides.

  14. Characterization of a mutant strain of a filamentous fungus Cladosporium phlei for the mass production of the secondary metabolite phleichrome.

    Science.gov (United States)

    Yi, Min-Hee; Kim, Jung-Ae; Kim, Jung-Mi; Park, Jin-Ah; Kim, Beom-Tae; Park, Seung-Moon; Yang, Moon-Sik; Hwang, Ki-Jun; Kim, Dae-Hyuk

    2011-08-01

    UV-mutagenesis was performed to obtain mutant strains that demonstrate altered production of phleichrome, a secondary metabolite of Cladosporium phlei. Among fifty mutants selected, based on the increased area and intensity of the purple pigment surrounding the colonies, the strain M0035 showed the highest production of phleichrome, more than seven fold over wild type. Plate cultures of the M0035 strain resulted in a total of 592 mg phleichrome consisting of 146 mg and 446 mg from the mycelia and agar media, respectively. The M0035 strain displayed a growth rate and a mycelial mass comparable to the parental strain but had significantly reduced asexual sporulation.

  15. In vitro characterization of Salmonella typhi mutant strains for live oral vaccines.

    Science.gov (United States)

    Dragunsky, E M; Rivera, E; Hochstein, H D; Levenbook, I S

    1990-06-01

    Several Salmonella typhi attenuated mutant strains, suggested as candidates for live oral vaccine, were examined for their characteristics in vitro in comparison with parental strains Ty2 and CDC10-80. Three methods were used: interaction of bacteria with the human monocyte-macrophage U937 cell line evaluated by microscopic examination, bacterial growth in the cell culture medium estimated by absorbance and bacterial resistance to human plasma assessed by the viable count technique. The most informative data were obtained in the test with U937 cells. Ty2 penetrated almost 100% of the cells, multiplied rapidly and caused death of the cells. CDC10-80 infected about 30% of the cells, multiplied slightly and did not kill the cells. The Ty2 mutant galE via EX462 behaved like CDC10-80. Bacteria of the galE Ty21a, Vi + Ty21a, 541 Ty and 543 Ty, found in only 3-4% of the cells, did not multiply within the cells and decreased in number with time. These findings correlate with the reported virulence of these strains for humans. With the second method, the rate of bacterial growth in cell culture medium did not differentiate Ty2, CDC10-80 and EX462. They grew at the same rate and faster than the remaining mutants. The plasma resistance test did not discriminate between EX462 and other mutants. These tests did not reveal any difference between Vi + Ty21a and Vi-Ty21a.

  16. Experimental infection of Mongolian gerbils with wild-type and mutant Helicobacter pylori strains.

    Science.gov (United States)

    Wirth, H P; Beins, M H; Yang, M; Tham, K T; Blaser, M J

    1998-10-01

    Experimental Helicobacter pylori infection was studied in Mongolian gerbils with fresh human isolates that carry or do not carry cagA (cagA-positive or cagA-negative, respectively), multiply passaged laboratory strains, wild-type strain G1.1, or isogenic ureA, cagA, or vacA mutants of G1.1. Animals were sacrificed 1 to 32 weeks after challenge, the stomach was removed from each animal for quantitative culture, urease test, and histologic testing, and blood was collected for antibody determinations. No colonization occurred after >/=20 in vitro passages of wild-type strain G1.1 or with the ureA mutant of G1.1. In contrast, infection occurred in animals challenged with wild-type G1.1 (99 of 101 animals) or the cagA (25 of 25) or vacA (25 of 29) mutant of G1.1. Infection with G1.1 persisted for at least 8 months. All 15 animals challenged with any of three fresh human cagA-positive isolates became infected, in contrast to only 6 (23%) of 26 animals challenged with one of four fresh human cagA-negative isolates (P < 0.001). Similar to infection in humans, H. pylori colonization of gerbils induced gastric inflammation and a systemic antibody response to H. pylori antigens. These data confirm the utility of gerbils as an animal model of H. pylori infection and indicate the importance of bacterial strain characteristics for successful infection.

  17. Comparative metabolic profiling of mce1 operon mutant vs wild-type Mycobacterium tuberculosis strains.

    Science.gov (United States)

    Queiroz, Adriano; Medina-Cleghorn, Daniel; Marjanovic, Olivera; Nomura, Daniel K; Riley, Lee W

    2015-11-01

    Mycobacterium tuberculosis disrupted in a 13-gene operon (mce1) accumulates free mycolic acids (FM) in its cell wall and causes accelerated death in mice. Here, to more comprehensively analyze differences in their cell wall lipid composition, we used an untargeted metabolomics approach to compare the lipid profiles of wild-type and mce1 operon mutant strains. By liquid chromatography-mass spectrometry, we identified >400 distinct lipids significantly altered in the mce1 mutant compared to wild type. These lipids included decreased levels of saccharolipids and glycerophospholipids, and increased levels of alpha-, methoxy- and keto mycolic acids (MA), and hydroxyphthioceranic acid. The mutant showed reduced expression of mmpL8, mmpL10, stf0, pks2 and papA2 genes involved in transport and metabolism of lipids recognized to induce proinflammatory response; these lipids were found to be decreased in the mutant. In contrast, the transcripts of mmpL3, fasI, kasA, kasB, acpM and RV3451 involved in MA transport and metabolism increased; MA inhibits inflammatory response in macrophages. Since the mce1 operon is known to be regulated in intracellular M. tuberculosis, we speculate that the differences we observed in cell wall lipid metabolism and composition may affect host response to M. tuberculosis infection and determine the clinical outcome of such an infection.

  18. Combinatorial depletion analysis to assemble the network architecture of the SAGA and ADA chromatin remodeling complexes.

    Science.gov (United States)

    Lee, Kenneth K; Sardiu, Mihaela E; Swanson, Selene K; Gilmore, Joshua M; Torok, Michael; Grant, Patrick A; Florens, Laurence; Workman, Jerry L; Washburn, Michael P

    2011-07-05

    Despite the availability of several large-scale proteomics studies aiming to identify protein interactions on a global scale, little is known about how proteins interact and are organized within macromolecular complexes. Here, we describe a technique that consists of a combination of biochemistry approaches, quantitative proteomics and computational methods using wild-type and deletion strains to investigate the organization of proteins within macromolecular protein complexes. We applied this technique to determine the organization of two well-studied complexes, Spt-Ada-Gcn5 histone acetyltransferase (SAGA) and ADA, for which no comprehensive high-resolution structures exist. This approach revealed that SAGA/ADA is composed of five distinct functional modules, which can persist separately. Furthermore, we identified a novel subunit of the ADA complex, termed Ahc2, and characterized Sgf29 as an ADA family protein present in all Gcn5 histone acetyltransferase complexes. Finally, we propose a model for the architecture of the SAGA and ADA complexes, which predicts novel functional associations within the SAGA complex and provides mechanistic insights into phenotypical observations in SAGA mutants.

  19. Carotenoid production and gene expression in an astaxanthin-overproducing Xanthophyllomyces dendrorhous mutant strain.

    Science.gov (United States)

    Castelblanco-Matiz, Lina M; Barbachano-Torres, Alejandra; Ponce-Noyola, Teresa; Ramos-Valdivia, Ana C; Cerda García-Rojas, Carlos M; Flores-Ortiz, César M; Barahona-Crisóstomo, Salvador K; Baeza-Cancino, Marcelo E; Alcaíno-Gorman, Jennifer; Cifuentes-Guzmán, Víctor H

    2015-12-01

    The primary carotenoid synthesized by Xanthophyllomyces dendrorhous is astaxanthin, which is used as a feed additive in aquaculture. Cell growth kinetics and carotenoid production were correlated with the mRNA levels of the idi, crtE, crtYB, crtI, crtS and crtR genes, and the changes in gene sequence between the wild-type and a carotenoid overproducer XR4 mutant strain were identified. At the late stationary phase, the total carotenoid content in XR4 was fivefold higher than that of the wild-type strain. Additionally, the mRNA levels of crtE and crtS increased during the XR4 growth and were three times higher than the wild-type strain in the late stationary phase. Moreover, the nucleotide sequences of crtYB, crtI and crtR exhibited differences between the strains. Both the higher crtE and crtS transcript levels and the crtYB, crtI and crtR mutations can, at least in part, act to up-regulate the carotenoid biosynthesis pathway in the XR4 strain.

  20. Two Arabidopsis orthologs of the transcriptional coactivator ADA2 have distinct biological functions.

    Science.gov (United States)

    Hark, Amy T; Vlachonasios, Konstantinos E; Pavangadkar, Kanchan A; Rao, Sumana; Gordon, Hillary; Adamakis, Ioannis-Dimosthenis; Kaldis, Athanasios; Thomashow, Michael F; Triezenberg, Steven J

    2009-02-01

    Histone acetylation is an example of covalent modification of chromatin structure that has the potential to regulate gene expression. Gcn5 is a prototypical histone acetyltransferase that associates with the transcriptional coactivator Ada2. In Arabidopsis, two genes encode proteins that resemble yeast ADA2 and share approximately 45% amino acid sequence identity. We previously reported that plants harboring a T-DNA insertion in the ADA2b gene display a dwarf phenotype with developmental defects in several organs. Here we describe T-DNA insertion alleles in the ADA2a gene, which result in no dramatic growth or developmental phenotype. Both ADA2a and ADA2b are expressed in a variety of plant tissues; moreover, expression of ADA2a from a constitutive promoter fails to complement the ada2b-1 mutant phenotype, consistent with the hypothesis that the two proteins have distinct biochemical roles. To further probe the cellular roles of ADA2a and ADA2b, we studied the response of the transcriptional coactivator mutants to abiotic stress. Although ada2b seedlings display hypersensitivity to salt and abscisic acid and altered responses to low temperature stress, the responses of ada2a seedlings to abiotic stress generally parallel those of wildtype plants. Intriguingly, ada2a;ada2b double mutant plants display an intermediate, gcn5-like phenotype, suggesting that ADA2a and ADA2b each work independently with GCN5 to affect genome function in Arabidopsis.

  1. Production of Ethanol by Indigenous Wild and Mutant Strain of Thermotolerant Kluyveromyces Marxianus Under Optimized Fermentation Conditions

    Directory of Open Access Journals (Sweden)

    Shaheen Aziz

    2009-12-01

    Full Text Available The maximum ethanol production and β-fructofuranocidase formation under fermentation studies were carried out in microprocessor controlled 23-L stainless steel fermenter at the following conditions: Temp = 40 ˚C (wild &mutant organism , pH= 5.5, carbon source (molasses=15% sugar nitrogen source (ammonium sulphate 0.75%, 300 RPM stirring speed and oxygen flow rate was 0.1 vvm. Mutant. Strain of thermotolerant Kluyveromyces marxianus M15 produced maximum production of ethanol at 48hr.All Kinetic Parameters have been studied for the utilization of substrate and production of maximum ethanol for both wild and mutant strains. It has been observed that wild strain was growing up to 550C while the mutant strain was growing up to 650C. In this comparison study, wild and mutant strain showed that Mutant-derived M15 was stronger over its parental culture due to its more thermal stability and production of ethanol at 65 oC at which wild organism could not grow.

  2. Characterization of a Mutant Listeria monocytogenes Strain Expressing Green Fluorescent Protein

    Institute of Scientific and Technical Information of China (English)

    Ling-Li JIANG; Hou-Hui SONG; Xue-Yan CHEN; Chun-Lin KE; Jing-Jing XU; Ning CHEN; Wei-Huan FANG

    2005-01-01

    To construct a recombinant strain of Listeria monocytogenes for the expression of heterologous genes, homologous recombination was utilized for insertional mutation, targeting its listeriolysin O gene(hly). The gene encoding green fluorescent protein (GFP) was used as the indicator of heterologous gene expression. The gene gfp was inserted into hly downstream from its promoter and signal sequence by an overlapping extension polymerase chain reaction, and was then cloned into the shuttle plasmid pKSV7 for allelic exchange with the L. monocytogenes chromosome. Homologous recombination was achieved by growing the electro-transformed L. monocytogenes cells on chloramphenicol plates at a non-permissive temperature.Sequencing analysis indicated correct insertion of the target gene in-frame with the signal sequence. The recombinant strain expressed GFP constitutively as revealed by fluorescence microscopy. The mutant strain L. monocytogenes hly-gfp lost its hemolytic activity as visualized on the blood agar or when analyzed with the culture supernatant samples. Such insertional mutation resulted in a reduced virulence of about 2 logs less than its parent strain L. monocytogenes 10403s as shown by the 50%-lethal-dose assays in the mouse and embryonated chicken egg models. These results thus demonstrate that mutated L. monocytogenes could be a potential carrier for the expression of heterologous passenger genes or could act as an indicator organism in the food industry.

  3. The Breeding of a Pigment Mutant Strain of Steroid Hydroxylation Aspergillus Flavus by Low Energy Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    YE Hui; MA Jingming; FENG Chun; CHENG Ying; ZHU Suwen; CHENG Beijiu

    2009-01-01

    In the process of the fermentation of steroid C11α-hydroxylgenation strain Aspergillus flavus AF-ANo208.a red pigment is derived.which will affect the isolation and purification of the target product.Low energy ion beam implantation is a new tool for breeding excellent mutant strains.In this study,the ion beam implantation experiments were performed by infusing two different ions:argon ion(Ar+)and nitrogen ion(N+).The results showed that the optimal ion implantation was N+ with an optimum dose of 2.08×1015 ions/cm2.with which the mutant strain AF-ANml6 that produced no red pigment was obtained.The strain had high genetic stability and kept the strong capacity of C11α-hydroxylgenation,which could be utilized in industrial fermentation.The difierences between the original strain and the mutant strain at a molecular level were analyzed by randomly amplified polymorphic DNA(RAPD).The results indicated that the frequency of variation Was 7.00%,which would establish the basis of application investigation into the breeding of pigment mutant strains by low energy ion implantation.

  4. Gas exchange in the filamentous cyanobacterium Nostoc punctiforme strain ATCC 29133 and Its hydrogenase-deficient mutant strain NHM5.

    Science.gov (United States)

    Lindberg, Pia; Lindblad, Peter; Cournac, Laurent

    2004-04-01

    Nostoc punctiforme ATCC 29133 is a nitrogen-fixing, heterocystous cyanobacterium of symbiotic origin. During nitrogen fixation, it produces molecular hydrogen (H(2)), which is recaptured by an uptake hydrogenase. Gas exchange in cultures of N. punctiforme ATCC 29133 and its hydrogenase-free mutant strain NHM5 was studied. Exchange of O(2), CO(2), N(2), and H(2) was followed simultaneously with a mass spectrometer in cultures grown under nitrogen-fixing conditions. Isotopic tracing was used to separate evolution and uptake of CO(2) and O(2). The amount of H(2) produced per molecule of N(2) fixed was found to vary with light conditions, high light giving a greater increase in H(2) production than N(2) fixation. The ratio under low light and high light was approximately 1.4 and 6.1 molecules of H(2) produced per molecule of N(2) fixed, respectively. Incubation under high light for a longer time, until the culture was depleted of CO(2), caused a decrease in the nitrogen fixation rate. At the same time, hydrogen production in the hydrogenase-deficient strain was increased from an initial rate of approximately 6 micro mol (mg of chlorophyll a)(-1) h(-1) to 9 micro mol (mg of chlorophyll a)(-1) h(-1) after about 50 min. A light-stimulated hydrogen-deuterium exchange activity stemming from the nitrogenase was observed in the two strains. The present findings are important for understanding this nitrogenase-based system, aiming at photobiological hydrogen production, as we have identified the conditions under which the energy flow through the nitrogenase can be directed towards hydrogen production rather than nitrogen fixation.

  5. Genomic sequence of a mutant strain of Caenorhabditis elegans with an altered recombination pattern

    Directory of Open Access Journals (Sweden)

    Marra Marco

    2010-02-01

    Full Text Available Abstract Background The original sequencing and annotation of the Caenorhabditis elegans genome along with recent advances in sequencing technology provide an exceptional opportunity for the genomic analysis of wild-type and mutant strains. Using the Illumina Genome Analyzer, we sequenced the entire genome of Rec-1, a strain that alters the distribution of meiotic crossovers without changing the overall frequency. Rec-1 was derived from ethylmethane sulfonate (EMS-treated strains, one of which had a high level of transposable element mobility. Sequencing of this strain provides an opportunity to examine the consequences on the genome of altering the distribution of meiotic recombination events. Results Using Illumina sequencing and MAQ software, 83% of the base pair sequence reads were aligned to the reference genome available at Wormbase, providing a 21-fold coverage of the genome. Using the software programs MAQ and Slider, we observed 1124 base pair differences between Rec-1 and the reference genome in Wormbase (WS190, and 441 between the mutagenized Rec-1 (BC313 and the wild-type N2 strain (VC2010. The most frequent base-substitution was G:C to A:T, 141 for the entire genome most of which were on chromosomes I or X, 55 and 31 respectively. With this data removed, no obvious pattern in the distribution of the base differences along the chromosomes was apparent. No major chromosomal rearrangements were observed, but additional insertions of transposable elements were detected. There are 11 extra copies of Tc1, and 8 of Tc2 in the Rec-1 genome, most likely the remains of past high-hopper activity in a progenitor strain. Conclusion Our analysis of high-throughput sequencing was able to detect regions of direct repeat sequences, deletions, insertions of transposable elements, and base pair differences. A subset of sequence alterations affecting coding regions were confirmed by an independent approach using oligo array comparative genome

  6. Isolation and characterization of symbiotic mutants of bradyrhizobium sp. (Arachis) strain NC92: mutants with host-specific defects in nodulation and nitrogen fixation.

    OpenAIRE

    Wilson, K. J.; Anjaiah, V; Nambiar, P T; Ausubel, F M

    1987-01-01

    Random transposon Tn5 mutagenesis of Bradyrhizobium sp. (Arachis) strain NC92, a member of the cowpea cross-inoculation group, was carried out, and kanamycin-resistant transconjugants were tested for their symbiotic phenotype on three host plants: groundnut, siratro, and pigeonpea. Two nodulation (Nod- phenotype) mutants were isolated. One is unable to nodulate all three hosts and appears to contain an insertion in one of the common nodulation genes (nodABCD); the other is a host-specific nod...

  7. Purification and characterisation of α-amylase produced by mutant strain of Aspergillus oryzae EMS-18.

    Science.gov (United States)

    Abdullah, Roheena; Ikram-ul-Haq

    2015-01-01

    α-Amylase produced by a mutant strain of Aspergillus oryzae EMS-18 has been purified to homogeneity as judged by sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was purified by using 70% ammonium sulphate precipitation followed by anion exchange chromatography on DEAE-Sephadex column and gel filtration on Sephadex G-100. An enzyme purification factor of 9.5-fold was achieved with a final specific activity of 1987.7 U/mg protein and overall yield of 23.8%. The molecular weight of purified α-amylase was estimated to be 48 kDa by SDS-PAGE. The purified enzyme revealed an optimum assay temperature and pH 40°C and 5.0, respectively. Except Ca(++) all other metal ions such as Mg, Mn, Na, Zn, Ni, Fe, Cu, Co and Ba were found to be inhibitory to enzyme activity.

  8. A mutant of Saccharomyces cerevisiae lacking catabolic NAD-specific glutamate dehydrogenase. Growth characteristics of the mutant and regulation of enzyme synthesis in the wild-type strain.

    Science.gov (United States)

    Middelhoven, W J; van Eijk, J; van Renesse, R; Blijham, J M

    1978-01-01

    NAD-specific glutamate dehydrogenase (GDH-B) was induced in a wild-type strain derived of alpha-sigma 1278b by alpha-amino acids, the nitrogen of which according to known degradative pathways is transferred to 2-oxoglutarate. A recessive mutant (gdhB) devoid of GDH-B activity grew more slowly than the wild type if one of these amino acids was the sole source of nitrogen. Addition of ammonium chloride, glutamine, asparagine or serine to growth media with inducing alpha-amino acids as the main nitrogen source increased the growth rate of the gdhB mutant to the wild-type level and repressed GDH-B synthesis in the wild type. Arginine, urea and allantoin similarly increased the growth rate of the gdhB mutant and repressed GDH-B synthesis in the presence of glutamate, but not in the presence of aspartate, alanine or proline as the main nitrogen source. These observations are consistent with the view that GDH-B in vivo deaminates glutamate. Ammonium ions are required for the biosynthesis of glutamine, asparagine, arginine, histidine and purine and pyrimidine bases. Aspartate and alanine apparently are more potent inducers of GDH-B than glutamate. Anabolic NADP-specific glutamate dehydrogenase (GDH-A) can not fulfil the function of GDH-B in the gdhB mutant. This is concluded from the equal growth rates in glutamate, aspartate and proline media as observed with a gdhB mutant and with a gdhA, gdhB double mutant in which both glutamate dehydrogenases area lacking. The double mutant showed an anomalous growth behaviour, growth rates on several nitrogen sources being unexpectedly low.

  9. Proteomic Analysis of Anti-Cancerous Scopularide Production by a Marine Microascus brevicaulis Strain and Its UV Mutant.

    Directory of Open Access Journals (Sweden)

    Annemarie Kramer

    Full Text Available The marine fungus Microascus brevicaulis strain LF580 is a non-model secondary metabolite producer with high yields of the two secondary metabolites scopularides A and B, which exhibit distinct activities against tumour cell lines. A mutant strain was obtained using UV mutagenesis, showing faster growth and differences in pellet formation besides higher production levels. Here, we show the first proteome study of a marine fungus. Comparative proteomics were applied to gain deeper understanding of the regulation of production and of the physiology of the wild type strain and its mutant. For this purpose, an optimised protein extraction protocol was established. In total, 4759 proteins were identified. The central metabolic pathway of strain LF580 was mapped using the KEGG pathway analysis and GO annotation. Employing iTRAQ labelling, 318 proteins were shown to be significantly regulated in the mutant strain: 189 were down- and 129 upregulated. Proteomics are a powerful tool for the understanding of regulatory aspects: The differences on proteome level could be attributed to limited nutrient availability in the wild type strain due to a strong pellet formation. This information can be applied for optimisation on strain and process level. The linkage between nutrient limitation and pellet formation in the non-model fungus M. brevicaulis is in consensus with the knowledge on model organisms like Aspergillus niger and Penicillium chrysogenum.

  10. Induced drought tolerance through wild and mutant bacterial strain Pseudomonas simiae in mung bean (Vigna radiata L.).

    Science.gov (United States)

    Kumari, Sarita; Vaishnav, Anukool; Jain, Shekhar; Varma, Ajit; Choudhary, Devendra Kumar

    2016-01-01

    The present study focused on the overproducing mutant of a plant growth promoting rhizobacterium (PGPR) Pseudomonas simiae strain AU (MTCC-12057) for significant drought tolerance in mung bean plants. Five mutants namely AU-M1, AU-M2, AU-M3, AU-M4 and AU-M5 were made after treatment of wild type strain with N-methyl-N-nitro-N-nitrosoguanidine. Mutant strain AU-M4 was recorded for enhanced ACC deaminase (ACC-D) activity, indole acetic acid (IAA) production and inorganic phosphate (Pi) solubilization compared to wild strain and other four mutant strains under drought condition. AU-M4 showed higher phosphate solubilization index (8.17) together with higher ACC-D activity (98 nmol/mg/h) and IAA concentration (69.35 µg/ml) compared with the wild type P. simiae strain AU ACC-D activity (79 nmol/mg/h) and IAA concentration (38.98 µg/ml) respectively. In this report, we investigated the effect of both wild and mutant type bacterial strain on mung bean plants under drought stress. Results showed that mutant AU-M4 and wild type strain AU inoculated plants exhibited superior tolerance against drought stress, as shown by their enhanced plant biomass (fresh weight), higher water content, higher proline accumulation and lower osmotic stress injury. Mutant AU-M4 and wild strain AU inoculated plants reduced the ethylene level by 59 and 45% respectively, compared to the control under stress condition. Furthermore, bacterial inoculated plants showed enhanced induced systemic drought tolerance by reducing stomata size and net photosynthesis resulting higher water content in mung bean plants that may help in survival of plants during drought condition. To mitigate the effects of drought stress, use of PGPR will be needed to ensure sufficient production of food from crop plants. Taking current leads available, concerted future research is needed in this area, particularly on field evaluation with application of potential microorganisms.

  11. Phenotypic and genotypic characterization of mutants of the virginiamycin producing strain 899 and its relatedness to the type strain of Streptomyces virginiae.

    Science.gov (United States)

    Lanoot, B; Vancanneyt, M; Hoste, B; Cnockaert, M C; Piecq, M; Gosselé, F; Swings, J

    2005-01-01

    A representative set of 19 mutants, with a known genealogy, of the virginiamycin producing strain Streptomyces virginiae 899 was investigated phenotypically and genotypically. Colour of the aerial and substrate mycelium were very variable both among spontaneous variants and those obtained after induced mutagenesis. At genotypic level, all mutants showed nearly identical BOX patterns, not reflecting the phenotypic heterogeneity observed. More than 40 years of forced mutational pressure did not cause huge chromosomal distortions but was most likely limited to base substitutions. The species S. virginiae, including besides producers of virginiamycin the type strain and non-type strains producing other bioactive compounds, is genomically heterogeneous on the basis of BOX-PCR fingerprinting and DNA-DNA hybridizations. The virginiamycin producing strain 899 does not belong to the species S. virginiae despite its phenotypic similarity to the latter.

  12. Mutant human myocilin induces strain specific differences in ocular hypertension and optic nerve damage in mice.

    Science.gov (United States)

    McDowell, Colleen M; Luan, Tomi; Zhang, Zhang; Putliwala, Tasneem; Wordinger, Robert J; Millar, J Cameron; John, Simon W M; Pang, Iok-Hou; Clark, Abbot F

    2012-07-01

    Elevated intraocular pressure (IOP) is a causative risk factor for the development and progression of glaucoma. Glaucomatous mutations in myocilin (MYOC) damage the trabecular meshwork and elevate IOP in humans and in mice. Animal models of glaucoma are important to discover and better understand molecular pathogenic pathways and to test new glaucoma therapeutics. Although a number of different animal models of glaucoma have been developed and characterized, there are no true models of human primary open angle glaucoma (POAG). The overall goal of this work is to develop the first inducible mouse model of POAG using a human POAG relevant transgene (i.e. mutant MYOC) expression in mouse eyes to elevate IOP and cause pressure-induced damage to the optic nerve. Four mouse strains (A/J, BALB/cJ, C57BL/6J, and C3H/HeJ) were used in this study. Ad5.MYOC.Y437H (5 × 10(7) pfu) was injected intravitreally into one eye, with the uninjected contralateral eye serving as the control eye. Conscious IOP measurements were taken using a TonoLab rebound tonometer. Optic nerve damage was determined by scoring PPD stained optic nerve cross sections. Retinal ganglion cell and superior colliculus damage was assessed by Nissl stain cell counts. Intravitreal administration of viral vector Ad5.MYOC.Y437H caused a prolonged, reproducible, and statistically significant IOP elevation in BALB/cJ, A/J, and C57BL/6J mice. IOPs increased to approximately 25 mm Hg for 8 weeks (p death or superior colliculus damage at the 8-week time point in any of the strains tested. These results demonstrate strain dependent responses to Ad5.MYOC.Y437H-induced ocular hypertension and pressure-induced optic nerve damage. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Improvement of heavy metal stress and toxicity assays by coupling a transgenic reporter in a mutant nematode strain

    Energy Technology Data Exchange (ETDEWEB)

    Chu, K.-W. [Department of Biology, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Chan, Shirley K.W. [Atmospheric, Marine and Coastal Environment Program, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Chow, King L. [Department of Biology, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China) and Atmospheric, Marine and Coastal Environment Program, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)]. E-mail: bokchow@ust.hk

    2005-09-30

    Previous studies have demonstrated that wild type Caenorhabditis elegans displays high sensitivity to heavy metals in a lethality test at a level comparable to that of other bioindicator organisms. Taking advantage of the genetics of this model organism, we have tested a number of mutant strains for enhanced sensitivity in heavy metal induced lethality and stress response. These mutants are defective in genes controlling dauer formation, longevity or response to reactive oxygen species (ROS). Among the tested mutants, a double mutant daf-16 unc-75 strain was identified to have superior sensitivity. It has a 6-, 3- and 2-fold increase in sensitivity to cadmium, copper and zinc, respectively, as compared with that of wild type animals. When a fluorescent reporter transgene was coupled with this double mutant for stress detection, a 10-fold enhancement of sensitivity to cadmium over the wild type strain was observed. These transgenic animals, superior to most of the model organisms currently used in bioassays for environmental pollutants, offer a fast and economic approach to reveal the bioavailability of toxic substance in field samples. This study also demonstrates that combination of genetic mutations and transgenesis is a viable approach to identify sensitive indicator animals for environmental monitoring.

  14. Functional analysis of an feoB mutant in Clostridium perfringens strain 13.

    Science.gov (United States)

    Awad, Milena M; Cheung, Jackie K; Tan, Joanne E; McEwan, Alastair G; Lyras, Dena; Rood, Julian I

    2016-10-01

    Bacterial pathogens have adopted numerous mechanisms for acquiring iron from host proteins during an infection, including the direct acquisition of ferric iron from heme-associated proteins or from iron-scavenging siderophores. Ferric iron then is transported into the cytosol, where it can be utilized by the bacterial pathogen. Under anaerobic conditions bacteria can also transport ferrous iron using the transmembrane complex FeoAB, but little is known about iron transport systems in anaerobic bacteria such as the pathogenic clostridia. In this study we sought to characterize the iron acquisition process in Clostridium perfringens. Bioinformatic analysis of the Clostridium perfringens strain 13 genome sequence revealed that it has seven potential iron acquisition systems: three siderophore-mediated systems, one ferric citrate uptake system, two heme-associated acquisition systems and one ferrous iron uptake system (FeoAB). The relative level of expression of these systems was determined using quantitative real-time RT-PCR assays that were specific for one gene from each system. Each of these genes was expressed, with the feoAB genes generating the most abundant iron-uptake related transcripts. To further examine the role of this system in the growth of C. perfringens, insertional inactivation was used to isolate a chromosomal feoB mutant. Growth of this mutant in the presence and absence of iron revealed that it had altered growth properties and a markedly reduced total iron and manganese content compared to the wild type; effects that were reversed upon complementation with the wild-type feoB gene. These studies suggest that under anaerobic conditions FeoB is the major protein required for the uptake of iron into the cell and that it may play an important role in the pathogenesis of C. perfringens infections.

  15. Structural characterization of bioengineered α-D-glucans produced by mutant glucansucrase GTF180 enzymes of lactobacillus reuteri strain 180

    NARCIS (Netherlands)

    Leeuwen, S.S. van; Kralj, S.; Eeuwema, W.; Gerwig, G.J.; Dijkhuizen, L.; Kamerling, J.P.

    2009-01-01

    Mutagenesis of specific amino acid residues of the glucansucrase (GTF180) enzyme from Lactobacillus reuteri strain 180 yielded 12 mutant enzymes that produced modified exopolysaccharides (mEPSs) from sucrose. Ethanol-precipitated and purified mEPSs were subjected to linkage analysis, Smith degradati

  16. Comparison Study on Colonization of hilA Mutant and Parent Strains of Salmonella enteritidis in Vertically Infected Broiler Chickens

    Directory of Open Access Journals (Sweden)

    MohammadSadegh Madadi

    2015-10-01

    Full Text Available Background: Salmonella actively stimulates its own uptake into the epithelial cells by inducing cytoskeleton rearrangements and membrane ruffling triggered by some proteins secreted by Salmonella into the cytosol of the epithelial cells via a type III secretion system (TTSS encoded bygenes of the Salmonella pathogenicity island 1 (SPI-1. hilA is a transcriptional activator encoded on Salmonella Pathogenicity Island 1 (SPI-1 genes.Methods: To assess the importance of hilA in a simulation modeling of vertical infection and shedding of S. enteritidis in broiler chickens a long-term experiment was designed. Two groups of 200 fertile eggs were inoculated with 20 colony forming units (CFU of hilA mutant of S. enteritidis or its parent strain just prior to incubation. Thirty five birds of each group were housed in separate rooms. On days 2, 4, 7, 14, 21, 28 and 35 of age, cloacal swabs from live birds as well as samples from internal organs (intestinal tract, liver and spleen were evaluated by bacteriological or molecular methods.Results: In most of sampling days colonization and invasion of parent strain S. enteritidis in intestine (especially ceaca and internal organs of chickens were higher with compared to its hilA mutant but this mutant strain could still colonize in intestinal tract and even invade liver or spleen.Conclusion: Colonization of hilA mutant of S. enteritidis indicated that hilA gene is only one part of the modulators in Salmonella invasion mechanism. The ability of hilA mutant to multiply and persist in host internal organs including ceaca may promise further research for potential of hilA mutant to prevent the initial colonization of the intestinal tract by a virulent S. enteritidis strain

  17. Ada & the Analytical Engine.

    Science.gov (United States)

    Freeman, Elisabeth

    1996-01-01

    Presents a brief history of Ada Byron King, Countess of Lovelace, focusing on her primary role in the development of the Analytical Engine--the world's first computer. Describes the Ada Project (TAP), a centralized World Wide Web site that serves as a clearinghouse for information related to women in computing, and provides a Web address for…

  18. The effect of gamma irradiation on astaxanthin synthetase encoding gene in two mutant strains of Phaffia rhodozyma.

    Directory of Open Access Journals (Sweden)

    Naeimeh Najafi

    2013-09-01

    Full Text Available Astaxanthin, an orange-red carotenoid pigment, acts as a protective agent against oxidative damage to cells in vivo. The astaxanthin synthetase gene (crtS size consists of 3995 bp. This gene has been suggested to catalyse β-carotene to astaxanthin in Phaffia rhodozyma. The aim of this research was to find any possible changes in this gene in two mutant strains, Gam1 and Gam2 (with high astaxanthin pigment production, previously created by gamma irradiation.The astaxanthin synthetase gene sequence of Phaffia rhodozyma in the NCBI Gene bank was used to design primer. In Gam1, this gene was amplified using primers Asta F1, Asta R2, Asta F3, Asta R4. In Gam2, primers asta F1, asta R4 were used to amplify the gene. The amplified fragments were 8 sequenced using primers Asta F1, Asta R1, Asta F2, Asta R2, Asta F3, Asta R3 and Asta F4, Asta R4. Astaxanthin synthetase gene from two mutant strains, Gam1 and Gam2 were amplified using PCR. The amplified products were sequenced and aligned using the ClustalW software.The comparison of this gene showed 98% and 99% similarities between the reference sequence and Gam1 and Gam2 mutant strains, respectively, whereas the comparison of this gene in Gam1 and Gam2 mutant strains showed 97% similarity. However, the deduced proteins showed 78% and 83% between the reference protein obtained from the wild type and Gam1 and Gam2, respectively. This similarity was 75% between the mutant strains.

  19. DNA polymorphism and total protein in mutants of Metarhizium anisopliae var. Anisopliae (Metsch.) Sorokin strain E9

    OpenAIRE

    Freire,Laurineide Lopes de Carvalho; Costa,Ana Bolena Lima da; Góes,Larissa Brandão; Oliveira,Neiva Tinti de

    2001-01-01

    Five mutants (MaE10, MaE27, MaE24, MaE41 e MaE49) of Metarhizium anisopliae wild strain E9 were analysed for DNA profile through the RAPD technique and for changes in total protein content by spectrophotometry, polyacrylamide gel electrophoresis and densitometry. The pattern of RAPD markers showed genetic polymorphism among the strains: out of twenty primers seven were selected, producing 113 bands. Forty seven bands were present in all strains (41.6% of monomorphic bands) and 66 showed polym...

  20. Assessing benzene-induced toxicity on wild type Euglena gracilis Z and its mutant strain SMZ.

    Science.gov (United States)

    Peng, Cheng; Arthur, Dionne M; Sichani, Homa Teimouri; Xia, Qing; Ng, Jack C

    2013-11-01

    Benzene is a representative member of volatile organic compounds and has been widely used as an industrial solvent. Groundwater contamination of benzene may pose risks to human health and ecosystems. Detection of benzene in the groundwater using chemical analysis is expensive and time consuming. In addition, biological responses to environmental exposures are uninformative using such analysis. Therefore, the aim of this study was to employ a microorganism, Euglena gracilis (E. gracilis) as a putative model to monitor the contamination of benzene in groundwater. To this end, we examined the wild type of E. gracilis Z and its mutant form, SMZ in their growth rate, morphology, chlorophyll content, formation of reactive oxygen species (ROS) and DNA damage in response to benzene exposure. The results showed that benzene inhibited cell growth in a dose response manner up to 48 h of exposure. SMZ showed a greater sensitivity compared to Z in response to benzene exposure. The difference was more evident at lower concentrations of benzene (0.005-5 μM) where growth inhibition occurred in SMZ but not in Z cells. We found that benzene induced morphological changes, formation of lipofuscin, and decreased chlorophyll content in Z strain in a dose response manner. No significant differences were found between the two strains in ROS formation and DNA damage by benzene at concentrations affecting cell growth. Based on these results, we conclude that E. gracilis cells were sensitive to benzene-induced toxicities for certain endpoints such as cell growth rate, morphological change, depletion of chlorophyll. Therefore, it is a potentially suitable model for monitoring the contamination of benzene and its effects in the groundwater.

  1. Behavioral characterization of a mutant mouse strain lacking D-amino acid oxidase activity.

    Science.gov (United States)

    Zhang, Min; Ballard, Michael E; Basso, Ana M; Bratcher, Natalie; Browman, Kaitlin E; Curzon, Pete; Konno, Ryuichi; Meyer, Axel H; Rueter, Lynne E

    2011-02-02

    D-amino acid oxidase (DAO), an enzyme that degrades d-serine, has been suggested as a susceptibility factor for schizophrenia. Here we sought to understand more about the behavioral consequence of lacking DAO and the potential therapeutic implication of DAO inhibition by characterizing a mouse strain (ddY/DAO(-)) lacking DAO activity. We found that the mutant mice showed enhanced prepulse inhibition responses (PPI). Intriguingly, DAO-/- mice had increased sensitivity to the PPI-disruptive effect induced by the competitive NMDA antagonist, SDZ 220-581. In the 24-h inhibitory avoidance test, DAO-/- mice were not different from DAO+/+ mice during the recall. In Barnes Maze, we found that DAO-/- mice had a shortened latency to enter the escape tunnel. Interestingly, although these mice were hypoactive when tested in a protected open field, they showed a profound increase of activity on the edge of the unprotected open field of the Barnes Maze even with the escape tunnel removed. This increased edge activity does not appear to be related to a reduced level of anxiety given that there were no significant genotype effects on the measures of anxiety-like behaviors in two standard animal models of anxiety, elevated plus maze and novelty suppressed feeding. Our data suggest that DAO-/- mice might have altered functioning of NMDARs. However, these results provide only modest support for manipulations of DAO activity as a potential therapeutic approach to treat schizophrenia.

  2. Residual virulence and immunogenicity of CGV26 and CGV2631 B. melitensis Rev. 1 deletion mutant strains in sheep after subcutaneous or conjunctival vaccination.

    Science.gov (United States)

    Guilloteau, Laurence A; Laroucau, Karine; Olivier, Michel; Grillo, Maria Jesus; Marin, Clara M; Verger, Jean-Michel; Blasco, Jose-Maria

    2006-04-24

    The CGV26 and CGV2631 strains are novel engineered Brucella melitensis Rev.1 mutant strains deleted for the bp26 gene or for both bp26 and omp31 genes, respectively, coding for proteins of diagnostic significance. The residual virulence and immunogenicity of both mutants were compared to the parental Rev.1 strain in sheep after subcutaneous or conjunctival vaccination. The deletion of the bp26 gene or both bp26 and omp31 genes had no significant effect on the intracellular survival of the Rev.1 strain in ovine macrophage cultures. The kinetics of infection induced by both mutants in sheep was similar to the Rev.1 strain, and inoculation by the subcutaneous route produced wider and more generalized infections than the conjunctival route. All strains were cleared from lymph nodes and organs within 3 months after inoculation. The CGV26 and CGV2631 mutants induced both specific systemic antibody response and lymphoproliferation in sheep. The kinetics of the responses induced by the mutants was quite similar to that of the parental Rev.1 strain, except for the intensity of the lymphoproliferative response, which was attenuated for the CGV2631 mutant. In conclusion, the residual virulence of both CGV26 and CGV2631 mutants in sheep was similar to that of the parental Rev.1 vaccine strain. These mutants induced also significant specific antibody and cell-mediated immunity in sheep and are suitable to be evaluated as potential vaccine candidates against B. melitensis and B. ovis infections in sheep.

  3. Analysis of genetic relationship in mutant silkworm strains of Bombyx mori using inter simple sequence repeat (ISSR) markers

    Institute of Scientific and Technical Information of China (English)

    Dhanikachalam Velu; Kangayam M. Ponnuvel; Murugiah Muthulakshmi; Randhir K. Sinha; Syed M.H. Qadri

    2008-01-01

    Amplified inter simple sequence repeats (ISSR) markers were used to determine genetic relationships among mutant silkworm strains of Bombyx mori. Fifteen ISSR primers containing simple sequence repeat (SSR) motifs were used in this study. A total of 113 markers were produced among 20 mutant swains, of which 73.45% were found to be polymorphic. In selected mutant genetic stocks, the average number of observed allele was (1.7080±0.4567), effective alleles (1.5194±0.3950) and genetic diversity (Ht) (0.2901±0.0415). The dendrogram produced using the unweighted pair group method with arithmetic means (UPGMA) and cluster analysis made using Nei's genetic distance resulted in the formation of one major group containing 6 groups separated 20 mutant silkworm strains. Therefore, ISSR amplification is a valuable method for determining the genetic variability among mutant silkworm swains. This efficient molecular marker would be useful for characterizing a considerable number of silkworm swains maintained at the germplasm center.

  4. Functional complementation of Leishmania (Leishmania) amazonensis AP endonuclease gene (lamap) in Escherichia coli mutant strains challenged with DNA damage agents.

    Science.gov (United States)

    Verissimo-Villela, Erika; Kitahara-Oliveira, Milene Yoko; Reis, Ana Beatriz de Bragança Dos; Albano, Rodolpho Mattos; Da-Cruz, Alda Maria; Bello, Alexandre Ribeiro

    2016-05-01

    During its life cycle Leishmania spp. face several stress conditions that can cause DNA damages. Base Excision Repair plays an important role in DNA maintenance and it is one of the most conserved mechanisms in all living organisms. DNA repair in trypanosomatids has been reported only for Old World Leishmania species. Here the AP endonuclease from Leishmania (L.) amazonensis was cloned, expressed in Escherichia coli mutants defective on the DNA repair machinery, that were submitted to different stress conditions, showing ability to survive in comparison to the triple null mutant parental strain BW535. Phylogenetic and multiple sequence analyses also confirmed that LAMAP belongs to the AP endonuclease class of proteins.

  5. Functional complementation of Leishmania (Leishmania) amazonensis AP endonuclease gene (lamap) in Escherichia coli mutant strains challenged with DNA damage agents

    Science.gov (United States)

    Verissimo-Villela, Erika; Kitahara-Oliveira, Milene Yoko; dos Reis, Ana Beatriz de Bragança; Albano, Rodolpho Mattos; Da-Cruz, Alda Maria; Bello, Alexandre Ribeiro

    2016-01-01

    During its life cycle Leishmania spp. face several stress conditions that can cause DNA damages. Base Excision Repair plays an important role in DNA maintenance and it is one of the most conserved mechanisms in all living organisms. DNA repair in trypanosomatids has been reported only for Old World Leishmania species. Here the AP endonuclease from Leishmania (L.) amazonensis was cloned, expressed in Escherichia coli mutants defective on the DNA repair machinery, that were submitted to different stress conditions, showing ability to survive in comparison to the triple null mutant parental strain BW535. Phylogenetic and multiple sequence analyses also confirmed that LAMAP belongs to the AP endonuclease class of proteins. PMID:27223868

  6. The N-terminus region of the putative C2H2 transcription factor Ada1 harbors a species-specific activation motif that regulates asexual reproduction in Fusarium verticillioides.

    Science.gov (United States)

    Malapi-Wight, Martha; Kim, Jung-Eun; Shim, Won-Bo

    2014-01-01

    Fusarium verticillioides is an important plant pathogenic fungus causing maize ear and stalk rots. In addition, the fungus is directly associated with fumonisin contamination of food and feeds. Here, we report the functional characterization of Ada1, a putative Cys2-His2 zinc finger transcription factor with a high level of similarity to Aspergillus nidulans FlbC, which is required for the activation of the key regulator of conidiation brlA. ADA1 is predicted to encode a protein with two DNA binding motifs at the C terminus and a putative activator domain at the N terminus region. Deletion of the flbC gene in A. nidulans results in "fluffy" cotton-like colonies, with a defect in transition from vegetative growth to asexual development. In this study we show that Ada1 plays a key role in asexual development in F. verticillioides. Conidia production was significantly reduced in the knockout mutantada1), in which aberrant conidia and conidiophores were also observed. We identified genes that are predicted to be downstream of ADA1, based on A. nidulans conidiation signaling pathway. Among them, the deletion of stuA homologue, FvSTUA, resulted in near absence of conidia production. To further investigate the functional conservation of this transcription factor, we complemented the Δada1 strain with A. nidulans flbC, F. verticillioides ADA1, and chimeric constructs. A. nidulans flbC failed to restore conidia production similar to the wild-type level. However, the Ada1N-terminal domain, which contains a putative activator, fused to A. nidulans FlbC C-terminal motif successfully complemented the Δada1 mutant. Taken together, Ada1 is an important transcriptional regulator of asexual development in F. verticillioides and that the N-terminus domain is critical for proper function of this transcription factor.

  7. Mutant strains of Spirulina (Arthrospira) platensis to increase the efficiency of micro-ecological life support systems

    Science.gov (United States)

    Brown, Igor

    The European Micro-Ecological Life Support System Alternative (MELiSSA) is an advanced idea for organizing a bioregenerative system for long term space flights and extraterrestrial settlements (Hendrickx, De Wever et al., 2005). Despite the hostility of both lunar and Martian environments to unprotected life, it seems possible to cultivate photosynthetic bacteria using closed bioreactors illuminated and heated by solar energy. Such reactors might be employed in critical processes, e.g. air revitalization, foodcaloric and protein source, as well as an immunomodulators production. The MELiSSA team suggested cyanobacterium Spirulina as most appropriate agent to revitalize air and produce a simple "fast" food. This is right suggestion because Spirulina was recently shown to be an oxygenic organism with the highest level of O2 production per unit mass (Ananyev et al., 2005). Chemical composition of Spirulina includes proteins (55Aiming to make Spirulina cultivation in life support systems like MELiSSA more efficient, we selected Spirulina mutant strains with increased fraction of methionine in the biomass of this cyanobacterium and compared the effect of parental wild strain of Spirulina and its mutants on the tendency of such experimental illnesses as radiationinduced lesions and hemolythic anemia. Results: It was found that mutant strains 198B and 27G contain higher quantities of total protein, essential amino acids, c-phycocyanin, allophycocyanin and chlorophyll a than parental wild strain of S. platensis. The strain 198B is also characterized with increased content of carotenoids. Revealed biochemical peculiarities of mutant strains suggest that these strains can serve as an additional source of essential amino acids as well as phycobiliproteins and carotenoids for the astronauts. Feeding animals suffering from radiation-induced lesions, c-phycocyanin, extracted from strain 27G, led to a correction in deficient dehydrogenase activity and energy-rich phosphate levels

  8. The Interactive ADA Workstation

    Science.gov (United States)

    1990-05-01

    3. Masking Union with Ada Homograph Definition 46 Figure 5-4. Direct Environment Computation with Masking Unions 50 Figure 5-5. Full Ada Body Direct...as a homograph test in Ada) that determines if two ele- ments are "indistinguishable" according to some criteria, the following rules determine...membership in a masking union: A member of the dominant set is a member of the masking union if and only if it has no homograph in the dominant set. In other

  9. Ada Test and Evaluation.

    Science.gov (United States)

    1980-05-01

    Lady Lovelace , the daughter of the poet, Lord Byron. Ada was Charles Babbage’s programmer, Babbage being the inventor of the first mechanical...34 O-07 0 ARFOCERIGTAEOAUIAL LABS RIGHTPATTERSON AFB OH F/G 9/2 ADA TEST AND EVALUATION.(U) MAY BO A J SCARPELLI UNCLASSIFIED AFWAL-TR-BO-1024 NL E...llEllllEIlE III HA i28 5__ BIH~~ ~ 2 __I.,11 LZ AFAL-TR-80-1024 Ada TEST AND EVALUATION Alfred J. Scarpelli System Technology Branch Systen Avionics

  10. Software engineering capability for Ada (GRASP/Ada Tool)

    Science.gov (United States)

    Cross, James H., II

    1995-01-01

    The GRASP/Ada project (Graphical Representations of Algorithms, Structures, and Processes for Ada) has successfully created and prototyped a new algorithmic level graphical representation for Ada software, the Control Structure Diagram (CSD). The primary impetus for creation of the CSD was to improve the comprehension efficiency of Ada software and, as a result, improve reliability and reduce costs. The emphasis has been on the automatic generation of the CSD from Ada PDL or source code to support reverse engineering and maintenance. The CSD has the potential to replace traditional prettyprinted Ada Source code. A new Motif compliant graphical user interface has been developed for the GRASP/Ada prototype.

  11. [Study of the transcriptional and transpositional activities of the Tirant retrotransposon in Drosophila melanogaster strains mutant for the flamenco locus].

    Science.gov (United States)

    Nefedova, L N; Urusov, F A; Romanova, N I; Shmel'kova, A O; Kim, A I

    2012-11-01

    Transpositions of the gypsy retrotransposon in the Drosophila melanogaster genome are controlled by the flamenco locus, which is represented as an accumulation of defective copies of transposable elements. In the present work, genetic control by the flamenco locus of the transcriptional and transpositional activities of the Tirant retrotransposon from the gypsy group was studied. Tissue-specific expression of Tirant was detected in the tissues of ovaries in a strain mutant for the flamenco locus. Tirant was found to be transpositionally active in isogenic D. melanogaster strains mutant for the flamenco locus. The sites of two new insertions have been localized by the method of subtractive hybridization. It has been concluded from the results obtained that the flamenco locus is involved in the genetic control of Tirant transpositions.

  12. Multi-omics approach to study global changes in a triclosan-resistant mutant strain of Acinetobacter baumannii ATCC 17978.

    Science.gov (United States)

    Fernando, Dinesh M; Chong, Patrick; Singh, Manu; Spicer, Victor; Unger, Mark; Loewen, Peter C; Westmacott, Garrett; Kumar, Ayush

    2017-01-01

    Acinetobacter baumannii AB042, a triclosan-resistant mutant strain, was examined for modulated gene expression using whole-genome sequencing, transcriptomics and proteomics in order to understand the mechanism of triclosan resistance as well as its impact on A. baumannii. Data revealed modulated expression of the fatty acid metabolism pathway, co-factors known to play a role in the synthesis of fatty acids, as well as several transcriptional regulators. The membrane composition of the mutant revealed a decrease in C18 with a corresponding increase in C16 fatty acids compared with the parent strain A. baumannii ATCC 17978. These data indicate that A. baumannii responds to triclosan by altering the expression of genes involved in fatty acid metabolism, antibiotic resistance and amino acid metabolism.

  13. Transcriptional changes in the nuc-2A mutant strain of Neurospora crassa cultivated under conditions of phosphate shortage.

    Science.gov (United States)

    Gras, Diana E; Silveira, Henrique C S; Peres, Nalu T A; Sanches, Pablo R; Martinez-Rossi, Nilce M; Rossi, Antonio

    2009-01-01

    The molecular mechanism that controls the response to phosphate shortage in Neurospora crassa involves four regulatory genes -nuc-2, preg, pgov, and nuc-1. Phosphate shortage is sensed by the nuc-2 gene, the product of which inhibits the functioning of the PREG-PGOV complex. This allows the translocation of the transcriptional factor NUC-1 into the nucleus, which activates the transcription of phosphate-repressible phosphatases. The nuc-2A mutant strain of N. crassa carries a loss-of-function mutation in the nuc-2 gene, which encodes an ankyrin-like repeat protein. In this study, we identified transcripts that are downregulated in the nuc-2A mutant strain. Functional grouping of these expressed sequence tags allowed the identification of genes that play essential roles in different cellular processes such as transport, transcriptional regulation, signal transduction, metabolism, protein synthesis, protein fate, and development. These results reveal novel aspects of the phosphorus-sensing network in N. crassa.

  14. Characterization of oxidative phosphorylation enzymes in Euglena gracilis and its white mutant strain W(gm)ZOflL.

    Science.gov (United States)

    Krnáčová, Katarína; Rýdlová, Ivana; Vinarčíková, Michaela; Krajčovič, Juraj; Vesteg, Matej; Horváth, Anton

    2015-03-12

    The enzymes involved in Euglena oxidative phosphorylation (OXPHOS) were characterized in this study. We have demonstrated that Euglena gracilis strain Z and its stable bleached non-photosynthetic mutant strain WgmZOflL both possess fully functional OXPHOS apparatus as well as pathways requiring terminal alternative oxidase(s) and alternative mitochondrial NADH-dehydrogenase(s). Light (or dark) and plastid (non)functionality seem to have little effect on oxygen consumption, the activities of the enzymes involved in OXPHOS and the action of respiration inhibitors in Euglena. This study also demonstrates biochemical properties of complex III (cytochrome c reductase) in Euglena.

  15. Proteomic Analysis of Anti-Cancerous Scopularide Production by a Marine Microascus brevicaulis Strain and Its UV Mutant

    DEFF Research Database (Denmark)

    Kramer, Annemarie; Beck, Hans Christian; Kumar, Abhishek

    2015-01-01

    growth and differences in pellet formation besides higher production levels. Here, we show the first proteome study of a marine fungus. Comparative proteomics were applied to gain deeper understanding of the regulation of production and of the physiology of the wild type strain and its mutant....... For this purpose, an optimised protein extraction protocol was established. In total, 4759 proteins were identified. The central metabolic pathway of strain LF580 was mapped using the KEGG pathway analysis and GO annotation. Employing iTRAQ labelling, 318 proteins were shown to be significantly regulated...

  16. Free mycolic acid accumulation in the cell wall of the mce1 operon mutant strain of Mycobacterium tuberculosis.

    Science.gov (United States)

    Cantrell, Sally A; Leavell, Michael D; Marjanovic, Olivera; Iavarone, Anthony T; Leary, Julie A; Riley, Lee W

    2013-10-01

    The lipid-rich cell wall of Mycobacterium tuberculosis, the agent of tuberculosis, serves as an effective barrier against many chemotherapeutic agents and toxic host cell effector molecules, and it may contribute to the mechanism of persistence. Mycobacterium tuberculosis strains mutated in a 13-gene operon called mce1, which encodes a putative ABC lipid transporter, induce aberrant granulomatous response in mouse lungs. Because of the postulated role of the mce1 operon in lipid importation, we compared the cell wall lipid composition of wild type and mce1 operon mutant M. tuberculosis H37Rv strains. High resolution mass spectrometric analyses of the mce1 mutant lipid extracts showed unbound mycolic acids to accumulate in the cell wall. Quantitative analysis revealed a 10.7 fold greater amount of free mycolates in the mutant compared to that of the wild type strain. The free mycolates were comprised of alpha, methoxy and keto mycolates in the ratio 1:0.9:0.6, respectively. Since the mce1 operon is regulated in vivo, the free mycolates that accumulate during infection may serve as a barrier for M. tuberculosis against toxic products and contribute to the pathogen's persistence.

  17. Constitutive expression of the tzs gene from Agrobacterium tumefaciens virG mutant strains is responsible for improved transgenic plant regeneration in cotton meristem transformation.

    Science.gov (United States)

    Ye, Xudong; Chen, Yurong; Wan, Yuechun; Hong, Yun-Jeong; Ruebelt, Martin C; Gilbertson, Larry A

    2016-03-01

    KEY MESSAGE : virG mutant strains of a nopaline type of Agrobacterium tumefaciens increase the transformation frequency in cotton meristem transformation. Constitutive cytokinin expression from the tzs gene in the virG mutant strains is responsible for the improvement. Strains of Agrobacterium tumefaciens were tested for their ability to improve cotton meristem transformation frequency. Two disarmed A. tumefaciens nopaline strains with either a virGN54D constitutively active mutation or virGI77V hypersensitive induction mutation significantly increased the transformation frequency in a cotton meristem transformation system. The virG mutant strains resulted in greener explants after three days of co-culture in the presence of light, which could be attributed to a cytokinin effect of the mutants. A tzs knockout strain of virGI77V mutant showed more elongated, less green explants and decreased cotton transformation frequency, as compared to a wild type parental strain, suggesting that expression of the tzs gene is required for transformation frequency improvement in cotton meristem transformation. In vitro cytokinin levels in culture media were tenfold higher in the virGN54D strain, and approximately 30-fold higher in the virGI77V strain, in the absence of acetosyringone induction, compared to the wild type strain. The cytokinin level in the virGN54D strain is further increased upon acetosyringone induction, while the cytokinin level in the virGI77V mutant is decreased by induction, suggesting that different tzs gene expression regulation mechanisms are present in the two virG mutant strains. Based on these data, we suggest that the increased cytokinin levels play a major role in increasing Agrobacterium attachment and stimulating localized division of the attached plant cells.

  18. [Analysis of the structure and expression of the DIP1 gene in Drosophila melanogaster strains mutant for the flamenco gene].

    Science.gov (United States)

    Nefedova, L N; Potanova, M V; Romanova, N I; Kim, A I

    2009-02-01

    DIP1 gene transcription was analyzed with the use of RT-PCR in three Drosophila melanogaster strains with the flamenco- phenotype (flam(SS), flam(MS), and flam(Ore)) and in one flamenco+ strain at the stages of embryos (0-24 h), third-instar larvae, and adult flies. The mutant strains flam(SS) and flam(Ore) lack an active copy of transposon gypsy. Theflam(MS) strain was obtained by introducing an active copy of gypsy in flies of theflam(SS) strain and is characterized by a high rate of gypsy transpositions. The experiments showed that at least five forms of DIP1 gene transcripts are produced. The form of cDNA corresponding to CDS DIP1-d was discovered only in embryos. It was found that DIP1 gene transcription depends on the age of flies: at the larval stage the level of transcription is significantly reduced. However, no reduction of gene transcription is observed in theflam(Ore) strain. These results suggest that the flamenco- phenotype may be associated with an alteration of DIP1 gene transcription, as in differentflamenco- strains the DIP1 gene expression is changed differently.

  19. A hydrogen-producing, hydrogenase-free mutant strain of Nostoc punctiforme ATCC 29133

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, P.; Lindblad, P. [Uppsala Univ. (Sweden). Dept. of Physiological Botany; Schuetz, K.; Happe, T. [Universitaet Bonn (Germany). Botanisches Inst.

    2002-12-01

    The hupL gene, encoding the uptake hydrogenase large subunit, in Nostoc sp. strain ATCC 29133, a strain lacking a bidirectional hydrogenase, was inactivated by insertional mutagenesis. Recombinant strains were isolated and analysed, and one hupL{sup -} strain, NHM5, was selected for further study. Cultures of NHM5 were grown under nitrogen-fixing conditions and H{sub 2} evolution under air was observed using an H{sub 2} electrode. (Author)

  20. Oxidative phosphorylation in Escherichia coli. Characterization of mutant strains in which F1-ATPase contains abnormal beta-subunits.

    Science.gov (United States)

    Senior, A E; Langman, L; Cox, G B; Gibson, F

    1983-02-15

    To facilitate study of the role of the beta-subunit in the membrane-bound proton-translocating ATPase of Escherichia coli, we identified mutant strains from which an F1-ATPase containing abnormal beta-subunits can be purified. Seventeen strains of E. coli, characterized by genetic complementation tests as carrying mutations in the uncD gene (which codes for the beta-subunit), were studied. The majority of these strains (11) were judged to be not useful, as their membranes lacked ATPase activity, and were either proton-permeable as prepared or remained proton-impermeable after washing with buffer of low ionic strength. A further two strains were of a type not hitherto reported, in that their membranes had ATPase activity, were proton-impermeable as prepared, and were not rendered proton-permeable by washing in buffer of low ionic strength. Presumably in these two strains F1-ATPase is not released in soluble form by this procedure. F1-ATPase of normal molecular size were purified from strains AN1340 (uncD478), AN937 (uncD430), AN938 (uncD431) and AN1543 (uncD484). F1-ATPase from strain AN1340 (uncD478) had 15% of normal specific Mg-dependent ATPase activity and 22% of normal ATP-synthesis activity. The F1-ATPase preparations from strains AN937, AN938 and AN1543 had respectively 1.7%, 1.8% and 0.2% of normal specific Mg-dependent ATPase activity, and each of these preparations had very low ATP-synthesis activity. The yield of F1-ATPase from the four strains described was almost twice that obtained from a normal haploid strain. The kinetics of Ca-dependent ATPase activity were unusual in each of the four F1-ATPase preparations. It is likely that these four mutant uncD F1-ATPase preparations will prove valuable for further experimental study of the F1-ATPase catalytic mechanism.

  1. In Vitro and In Vivo Characterization of a Bordetella bronchiseptica Mutant Strain with a Deep Rough Lipopolysaccharide Structure

    Science.gov (United States)

    Sisti, Federico; Fernández, Julieta; Rodríguez, María Eugenia; Lagares, Antonio; Guiso, Nicole; Hozbor, Daniela Flavia

    2002-01-01

    Bordetella bronchiseptica is closely related to Bordetella pertussis, which produces respiratory disease primarily in mammals other than humans. However, its importance as a human pathogen is being increasingly recognized. Although a large amount of research on Bordetella has been generated regarding protein virulence factors, the participation of the surface lipopolysaccharide (LPS) during B. bronchiseptica infection is less understood. To get a better insight into this matter, we constructed and characterized the behavior of an LPS mutant with the deepest possible rough phenotype. We generated the defective mutant B. bronchiseptica LP39 on the waaC gene, which codes for a heptosyl transferase involved in the biosynthesis of the core region of the LPS molecule. Although in B. bronchiseptica LP39 the production of the principal virulence determinants adenylate cyclase-hemolysin, filamentous hemagglutinin, and pertactin persisted, the quantity of the two latter factors was diminished, with the levels of pertactin being the most greatly affected. Furthermore, the LPS of B. bronchiseptica LP39 did not react with sera obtained from mice that had been infected with the parental strain, indicating that this defective LPS is immunologically different from the wild-type LPS. In vivo experiments demonstrated that the ability to colonize the respiratory tract is reduced in the mutant, being effectively cleared from lungs within 5 days, whereas the parental strain survived at least for 30 days. In vitro experiments have demonstrated that, although B. bronchiseptica LP39 was impaired for adhesion to human epithelial cells, it is still able to survive within the host cells as efficiently as the parental strain. These results seem to indicate that the deep rough form of B. bronchiseptica LPS cannot represent a dominant phenotype at the first stage of colonization. Since isolates with deep rough LPS phenotype have already been obtained from human B. bronchiseptica chronic

  2. Functionality of cryopreserved juvenile ovaries from mutant mice in different genetic background strains after allotransplantation

    NARCIS (Netherlands)

    Huang, K.Y.; Groot, de S.A.; Woelders, H.; Horst, van der G.T.J.; Themmen, A.P.N.; Colenbrander, B.; Fentener van Vlissingen, J.M.

    2010-01-01

    The rapid expansion of mutant mouse colonies for biomedical research has resulted in lack of space at laboratory animal facilities and increasing risks of losing precious lines. These challenges require cheap and effective methods in addition to freezing embryos and sperm to archive the expanding mu

  3. Isolation and characterization of the E. coli membrane protein production strain Mutant56(DE3)

    NARCIS (Netherlands)

    Baumgarten, Thomas; Schlegel, Susan; Wagner, Samuel; Löw, Mirjam; Eriksson, Jonas; Bonde, Ida; Herrgård, Markus J; Heipieper, Hermann J; Nørholm, Morten H H; Slotboom, Dirk Jan; de Gier, Jan-Willem

    2017-01-01

    Membrane protein production is usually toxic to E. coli. However, using genetic screens strains can be isolated in which the toxicity of membrane protein production is reduced, thereby improving production yields. Best known examples are the C41(DE3) and C43(DE3) strains, which are both derived from

  4. [Separation of the biosynthesis products of a mutant strain of Actinomyces chrysomallus var. carotenoides and the identification of actinomycin antibiotics].

    Science.gov (United States)

    Sverdlova, A N; Nefelova, M V; Silaev, A B

    1979-01-01

    An orange antibiotically active substance isolated from the mycelium of a mutant strain of Actinomyces chrysomallus var. carotenoides was identified as a mixture of actinomycins according to its light absorption spectra, circular dichroism spectra, IR spectra and chromatographic comparison with the standard samples. A scheme for successive extraction of the biologically active substances from the mycelium resulting in isolation of a fraction enriched with antibiotic substances and a fraction enriched with pigments is presented. A method for separation and purification of 3 groups of biologically active substances from the mycelium enriched extract was developed.

  5. A LISP-Ada connection

    Science.gov (United States)

    Jaworski, Allan; Lavallee, David; Zoch, David

    1987-01-01

    The prototype demonstrates the feasibility of using Ada for expert systems and the implementation of an expert-friendly interface which supports knowledge entry. In the Ford LISP-Ada Connection (FLAC) system LISP and Ada are used in ways which complement their respective capabilities. Future investigation will concentrate on the enhancement of the expert knowledge entry/debugging interface and on the issues associated with multitasking and real-time expert systems implementation in Ada.

  6. Restoration of growth by manganese in a mutant strain of Escherichia coli lacking most known iron and manganese uptake systems

    DEFF Research Database (Denmark)

    Taudte, Nadine; German, Nadezhda; Zhu, Yong-Guan

    2016-01-01

    The interplay of manganese and iron homeostasis and oxidative stress in Escherichia coli can give important insights into survival of bacteria in the phagosome and under differing iron or manganese bioavailabilities. Here, we characterized a mutant strain devoid of all know iron/manganese......-uptake systems relevant for growth in defined medium. Based on these results an exit strategy enabling the cell to cope with iron depletion and use of manganese as an alternative for iron could be shown. Such a strategy would also explain why E. coli harbors some iron- or manganese-dependent iso......-enzymes such as superoxide dismutases or ribonucleotide reductases. The benefits for gaining a means for survival would be bought with the cost of less efficient metabolism as indicated in our experiments by lower cell densities with manganese than with iron. In addition, this strain was extremely sensitive to the metalloid...

  7. Ada Implementation Guide. Software Engineering With Ada. Volume 2

    Science.gov (United States)

    1994-04-01

    international standard LADY-LOV 11/25/91 10240 Article on life of Ada Lovelace by Carol L. James and Duncan E. Morrill with note on the naming of the Ada ...A aa a- S I !/ A -- I Volume II I I! I Ii Ada Implementation GuideI Software Engineering With Ada I DTIC QUALn1T :1 1 ’. I April 1994 *ýS94-18856 JJ...A-13 A.1 Government Sources ...................................... A-1 A.1.1 Organizations .................................... A-2 Ada

  8. Benchmark Lisp And Ada Programs

    Science.gov (United States)

    Davis, Gloria; Galant, David; Lim, Raymond; Stutz, John; Gibson, J.; Raghavan, B.; Cheesema, P.; Taylor, W.

    1992-01-01

    Suite of nonparallel benchmark programs, ELAPSE, designed for three tests: comparing efficiency of computer processing via Lisp vs. Ada; comparing efficiencies of several computers processing via Lisp; or comparing several computers processing via Ada. Tests efficiency which computer executes routines in each language. Available for computer equipped with validated Ada compiler and/or Common Lisp system.

  9. Industrial robustness: understanding the mechanism of tolerance for the Populus hydrolysate-tolerant mutant strain of Clostridium thermocellum.

    Directory of Open Access Journals (Sweden)

    Jessica L Linville

    Full Text Available BACKGROUND: An industrially robust microorganism that can efficiently degrade and convert lignocellulosic biomass into ethanol and next-generation fuels is required to economically produce future sustainable liquid transportation fuels. The anaerobic, thermophilic, cellulolytic bacterium Clostridium thermocellum is a candidate microorganism for such conversions but it, like many bacteria, is sensitive to potential toxic inhibitors developed in the liquid hydrolysate produced during biomass processing. Microbial processes leading to tolerance of these inhibitory compounds found in the pretreated biomass hydrolysate are likely complex and involve multiple genes. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we developed a 17.5% v/v Populus hydrolysate tolerant mutant strain of C. thermocellum by directed evolution. The genome of the wild type strain, six intermediate population samples and seven single colony isolates were sequenced to elucidate the mechanism of tolerance. Analysis of the 224 putative mutations revealed 73 high confidence mutations. A longitudinal analysis of the intermediate population samples, a pan-genomic analysis of the isolates, and a hotspot analysis revealed 24 core genes common to all seven isolates and 8 hotspots. Genetic mutations were matched with the observed phenotype through comparison of RNA expression levels during fermentation by the wild type strain and mutant isolate 6 in various concentrations of Populus hydrolysate (0%, 10%, and 17.5% v/v. CONCLUSION/SIGNIFICANCE: The findings suggest that there are multiple mutations responsible for the Populus hydrolysate tolerant phenotype resulting in several simultaneous mechanisms of action, including increases in cellular repair, and altered energy metabolism. To date, this study provides the most comprehensive elucidation of the mechanism of tolerance to a pretreated biomass hydrolysate by C. thermocellum. These findings make important contributions to the

  10. Optimisation of nutritional requirements for dopamine synthesis by calcium alginate-entrapped mutant strain of Aspergillus oryzae EMS-6.

    Science.gov (United States)

    Ali, Sikander; Nawaz, Wajeeha

    2017-02-01

    The optimisation of nutritional requirements for dopamine (DA) synthesis by calcium alginate-entrapped mutant variant of Aspergillus oryzae EMS-6 using submerged fermentation technique was investigated. A total of 13 strains were isolated from soil. Isolate I-2 was selected as a better producer of DA and improved by exposing with ethyl methylsulphonate (EMS). EMS-6 was selected as it exhibited 43 μg/mL DA activity. The mutant variable was further treated with low levels of l-cysteine HCl to make it resistant against diversion and environmental stress. The conidiospores of mutant variant were entrapped in calcium alginate beads for stable product formation. EMS-6 gave maximum DA activity (124 μg/mL) when supplemented with 0.1% peptone and 0.2% sucrose, under optimised parameters viz. pH 3, temperature of 55 °C and incubation time of 70 min. The study involves the high profile of DA activity and is needed, as DA is capable to control numerous neurogenic disorders.

  11. [A recessive mutant causing testicular/ovarian teratoma in rats (Tera strain)].

    Science.gov (United States)

    Miwa, M; Kojima, M; Ohtani, T; Tsuji, K

    1987-04-01

    A hereditary testicular/ovarian teratoma strain (Tera) of rats was developed from the Csk: Wistar-Imamichi strain. As the teratoma consisted of tridermic tissues such as bone, epithelium and neural tissue, it was diagnosed as triphyllomatous teratoma. The frequency of the teratoma was about 25% in either sex, with no sexual difference. Accordingly, the heredity of the teratoma appeared to be an autosomal single recessive trait (symbol, tera).

  12. Establishing a Markerless Genetic Exchange System for Methanosarcina mazei Strain Gö1 for Constructing Chromosomal Mutants of Small RNA Genes

    Directory of Open Access Journals (Sweden)

    Claudia Ehlers

    2011-01-01

    Full Text Available A markerless genetic exchange system was successfully established in Methanosarcina mazei strain Gö1 using the hpt gene coding for hypoxanthine phosphoribosyltransferase. First, a chromosomal deletion mutant of the hpt gene was generated conferring resistance to the purine analog 8-aza-2,6-diaminopurine (8-ADP. The nonreplicating allelic exchange vector (pRS345 carrying the pac-resistance cassette for direct selection of chromosomal integration, and the hpt gene for counterselection was introduced into this strain. By a pop-in and ultimately pop-out event of the plasmid from the chromosome, allelic exchange is enabled. Using this system, we successfully generated a M. mazei deletion mutant of the gene encoding the regulatory non-coding RNA sRNA154. Characterizing M. mazei Δ154 under nitrogen limiting conditions demonstrated differential expression of at least three cytoplasmic proteins and reduced growth strongly arguing for a prominent role of sRNA154 in regulation of nitrogen fixation by posttranscriptional regulation.

  13. Study on the molecular basis of glucoamylase overproduc-tion of a mutant strain Aspergillus niger T21

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The molecular basis for increasing of the glucoamylase (GLA) production of an Aspergillus niger mutant T21 was investigated . Northern blot analysis showed that the amount of glaA specific mRNA of A . niger T21 was about 20 times higher than that of its start strain A . niger AS 3.795. The two glaA promoter fusions (PglaA)-uidAs were respectively introduced into A . niger. Analysis of GUS activity of the transformants revealed that the PglaA activity of the strain T21 is about 3 times stronger than that of the strain AS 3.795. It is considered to be one of the reasons for the increase of glaA transcriptional level in the strain T21. However, comparing with the 20 times increase in the amount of glaA mRNA the alteration of trans regulation should be the most important reason for that. The results of deletion analysis of 5′-cis region of A . niger T21 glaA gene indicated that the region from - 408 to - 513 bp upstream of ATG is responsible for the high level expression of glaA.

  14. The AdaBoost Flow

    OpenAIRE

    Lykov, A.; Muzychka, S.; Vaninsky, K.

    2011-01-01

    We introduce a dynamical system which we call the AdaBoost flow. The flow is defined by a system of ODEs with control. We show that three algorithms of the AdaBoost family (i) the AdaBoost algorithm of Schapire and Freund (ii) the arc-gv algorithm of Breiman (iii) the confidence rated prediction of Schapire and Singer can be can be embedded in the AdaBoost flow. The nontrivial part of the AdaBoost flow equations coincides with the equations of dynamics of nonperiodic Toda system written in te...

  15. A non-sense mutation in the putative anti-mutator gene ada/alkA of Mycobacterium tuberculosis and M. bovis isolates suggests convergent evolution

    Directory of Open Access Journals (Sweden)

    Gicquel Brigitte

    2007-05-01

    Full Text Available Abstract Background Previous studies have suggested that variations in DNA repair genes of W-Beijing strains may have led to transient mutator phenotypes which in turn may have contributed to host adaptation of this strain family. Single nucleotide polymorphism (SNP in the DNA repair gene mutT1 was identified in MDR-prone strains from the Central African Republic. A Mycobacteriumtuberculosis H37Rv mutant inactivated in two DNA repair genes, namely ada/alkA and ogt, was shown to display a hypermutator phenotype. We then looked for polymorphisms in these genes in Central African Republic strains (CAR. Results In this study, 55 MDR and 194 non-MDR strains were analyzed. Variations in DNA repair genes ada/alkA and ogt were identified. Among them, by comparison to M. tuberculosis published sequences, we found a non-sense variation in ada/alkA gene which was also observed in M. bovis AF2122 strain. SNPs that are present in the adjacent regions to the amber variation are different in M. bovis and in M. tuberculosis strain. Conclusion An Amber codon was found in the ada/alkA locus of clustered M. tuberculosis isolates and in M. bovis strain AF2122. This is likely due to convergent evolution because SNP differences between strains are incompatible with horizontal transfer of an entire gene. This suggests that such a variation may confer a selective advantage and be implicated in hypermutator phenotype expression, which in turn contributes to adaptation to environmental changes.

  16. Fluoroquinolone and Quinazolinedione Activities against Wild-Type and Gyrase Mutant Strains of Mycobacterium smegmatis▿

    Science.gov (United States)

    Malik, Muhammad; Marks, Kevin R.; Mustaev, Arkady; Zhao, Xilin; Chavda, Kalyan; Kerns, Robert J.; Drlica, Karl

    2011-01-01

    Quinazolinediones (diones) are fluoroquinolone-like inhibitors of bacterial gyrase and DNA topoisomerase IV. To assess activity against mycobacteria, C-8-methoxy dione derivatives were compared with cognate fluoroquinolones by using cultured Mycobacterium smegmatis. Diones exhibited higher MIC values than fluoroquinolones; however, MICs for fluoroquinolone-resistant gyrA mutants, normalized to the MIC for wild-type cells, were lower. Addition of a 3-amino group to the 2,4-dione core increased relative activity against mutants, while alteration of the 8-methoxy group to a methyl or of the 2,4-dione core to a 1,3-dione core lowered activity against mutants. A GyrA G89C bacterial variant was strikingly susceptible to most of the diones tested; in contrast, low susceptibility to fluoroquinolones was observed. Many of the bacteriostatic differences between diones and fluoroquinolones were explained by interactions at the N terminus of GyrA helix IV revealed by recently published X-ray structures of drug-topoisomerase-DNA complexes. When lethal activity was normalized to the MIC in order to minimize the effects of drug uptake, efflux, and ternary complex formation, a 3-amino-2,4-dione exhibited killing activity comparable to that of a cognate fluoroquinolone. Surprisingly, the lethal activity of the dione was inhibited less by chloramphenicol than that of the cognate fluoroquinolone. This observation adds the 2,4-dione structural motif to the list of structural features known to impart lethality to fluoroquinolone-like compounds in the absence of protein synthesis, a phenomenon that is not explained by X-ray structures of drug-enzyme-DNA complexes. PMID:21383100

  17. Non-spa-typeable clinical Staphylococcus aureus strains are naturally occurring protein A mutants

    DEFF Research Database (Denmark)

    Baum, Cathrin; Haslinger-Löffler, Bettina; Westh, Henrik;

    2009-01-01

    Staphylococcus aureus is a major human pathogen responsible for increasing the prevalence of community- and hospital-acquired infections. Protein A (SpA) is a key virulence factor of S. aureus and is highly conserved. Sequencing of the variable-number tandem-repeat region of SpA (spa typing......) provides a rapid and reliable method for epidemiological studies. Rarely, non-spa-typeable S. aureus strains are encountered. The reason for this is not known. In this study, we characterized eight non-spa-typeable bacteremia isolates. Sequencing of the entire spa locus was successful for five strains...

  18. Funduscopy in adult zebrafish and its application to isolate mutant strains with ocular defects.

    Directory of Open Access Journals (Sweden)

    Markus Tschopp

    Full Text Available Funduscopy is one of the most commonly used diagnostic tools in the ophthalmic practice, allowing for a ready assessment of pathological changes in the retinal vasculature and the outer retina. This non-invasive technique has so far been rarely used in animal model for ophthalmic diseases, albeit its potential as a screening assay in genetic screens. The zebrafish (Danio rerio is well suited for such genetic screens for ocular alterations. Therefore we developed funduscopy in adult zebrafish and employed it as a screening tool to find alterations in the anterior segment and the fundus of the eye of genetically modified adult animals.A stereomicroscope with coaxial reflected light illumination was used to obtain fundus color images of the zebrafish. In order to find lens and retinal alterations, a pilot screen of 299 families of the F3 generation of ENU-treated adult zebrafish was carried out.Images of the fundus of the eye and the anterior segment can be rapidly obtained and be used to identify alterations in genetically modified animals. A number of putative mutants with cataracts, defects in the cornea, eye pigmentation, ocular vessels and retina were identified. This easily implemented method can also be used to obtain fundus images from rodent retinas.In summary, we present funduscopy as a valuable tool to analyse ocular abnormalities in adult zebrafish and other small animal models. A proof of principle screen identified a number of putative mutants, making funduscopy based screens in zebrafish feasible.

  19. Global transcriptional analysis of spontaneous sakacin P-resistant mutant strains of Listeria monocytogenes during growth on different sugars.

    Directory of Open Access Journals (Sweden)

    Girum Tadesse Tessema

    Full Text Available Subclass IIa bacteriocins have strong antilisterial activity and can control the growth of Listeria monocytogenes in food. However, L. monocytogenes may develop resistance towards such bacteriocins. In this follow-up study, the transcriptomes of a high level (L502-1 and a low level (L502-6 spontaneous sakacin P-resistant mutant strain of L. monocytogenes were compared to the wild-type (L502. The growth of the resistant strains was reduced on mannose but not affected on cellobiose and the transcriptomics was performed during growth on these sugars. The mannose phosphotransferase system (PTS encoded by the mptACD operon (mpt is known for transporting mannose and also act as a receptor to class IIa bacteriocins. The mpt was repressed in L502-1 and this is in accordance with abolition of the bacteriocin receptor with resistance to class IIa bacteriocins. In contrast, the mpt was induced in L502-6. Despite the induction of the mpt, L502-6 showed 1,000 times more resistance phenotype and reduced growth on mannose suggesting the mannose-PTS may not be functional in L502-6. The microarray data suggests the presence of other transcriptional responses that may be linked to the sakacin P resistance phenotype particularly in L502-6. Most of commonly regulated genes encode proteins involved in transport and energy metabolism. The resistant strains displayed shift in general carbon catabolite control possibly mediated by the mpt. Our data suggest that the resistant strains may have a reduced virulence potential. Growth sugar- and mutant-specific responses were also revealed. The two resistant strains also displayed difference in stability of the sakacin P resistance phenotype, growth in the presence of both the lytic bacteriophage P100 and activated charcoal. Taken together, the present study showed that a single time exposure to the class IIa bacteriocin sakacin P may elicit contrasting phenotypic and transcriptome responses in L. monocytogenes possibly

  20. Ada Compiler Validation Summary Report: NYU Ada/ED, Version 19.7 V-001.

    Science.gov (United States)

    1983-04-11

    ETs4~4 B37201A.ADA P SCz28 CTx7O ECal3 B37202A.ADA P SC.=44 CT263 ECaig B37202B. ADA P SCz ? CTz8 ECzl B37203A.ADA P SCz14I CTxl9 ECx6 aB3720IA-AB.ADA P...SCx27 CT=61 LT z12. 8 £7.49C52005C.ADA P SCz17 C7.37 LTx11.0 £Tx48 C52005D.ADA P SCz -53 CTz107 1.7.15.7 E7.76 C52005E.ADA P Scx39 C7.87 1.7.13.5 £7.52...SCa? C7.21 ECal B55AOlD-AB.ADk P SCx ? C7.13 M~al D55A01£-AB.ADA P SC.? CTwl7 ECal B55AOlF-AB.ADA P SCull CTx12 ECal B55A01G-AB.ADA P SCull C~zl6 ECal

  1. Modelling Hepatitis B Virus Antiviral Therapy and Drug Resistant Mutant Strains

    Science.gov (United States)

    Bernal, Julie; Dix, Trevor; Allison, Lloyd; Bartholomeusz, Angeline; Yuen, Lilly

    Despite the existence of vaccines, the Hepatitis B virus (HBV) is still a serious global health concern. HBV targets liver cells. It has an unusual replication process involving an RNA pre-genome that the reverse transcriptase domain of the viral polymerase protein translates into viral DNA. The reverse transcription process is error prone and together with the high replication rates of the virus, allows the virus to exist as a heterogeneous population of mutants, known as a quasispecies, that can adapt and become resistant to antiviral therapy. This study presents an individual-based model of HBV inside an artificial liver, and associated blood serum, undergoing antiviral therapy. This model aims to provide insights into the evolution of the HBV quasispecies and the individual contribution of HBV mutations in the outcome of therapy.

  2. Biogenesis and Ultrastructure of Carboxysomes from Wild Type and Mutants of Synechococcus sp. Strain PCC 7942.

    Science.gov (United States)

    Orus, M. I.; Rodriguez, M. L.; Martinez, F.; Marco, E.

    1995-04-01

    Immature inclusions representing three progressive steps of carboxysome biogenesis have been identified in Synechococcus during the period of adaptation to low-CO2 conditions: (a) ring-shaped structures, (b) electron-translucent inclusions with the shape of a carboxysome and the internal orderly arrangement of ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) molecules, and (c) carboxysomes with an internal electron-translucent area, which seem to be the penultimate stage of carboxysome maturation. The ability to build up normal carboxysomes is impaired in three (M3, EK6, and D4) of four high-carbon-requiring mutants studied in this work. M3 and EK6 exhibit abundant immature electron-translucent carboxysomes but no mature ones. This finding supports the contention that an open reading frame located 7.5 kb upstream of the gene encoding the large subunit of Rubisco (altered in M3) is involved in the carboxysome composition and confirms the structural role of the small subunit of Rubisco (slightly modified in EK6) in the assembly of these structures. D4 shows few typical carboxysomes and frequent immature types, its genetic lesion affecting the apparently unrelated gene encoding a subunit of phosphoribosyl aminoamidazole carboxylase of the purine biosynthesis pathway. Revertants EK20 (EK6) and RK13 (D4) have normal carboxysomes, which means that the restoration of the ability to grow under low CO2 coincides with the proper assembling of these structures. N5, a transport mutant due to the alteration of the gene encoding subunit 2 of NADH dehydrogenase, shows an increase in the number and size of carboxysomes and frequent bar-shaped ones.

  3. Optimization of Process Parameters for Conversion of 3-cyanpyridine to Nicotinamide Using Resting Cells of Mutant 4D Strain of Rhodococcus rhodochrous PA-34

    Directory of Open Access Journals (Sweden)

    Amit Seth

    2011-11-01

    Full Text Available Mutant of Rhodococcus rhodochrous PA-34, named as 'mutant 4D' has been reported for the hyperconversion of 3-cyanopyridine to nicotinamide. This mutant 4D generated through chemical mutagenesis has much more hydration potential than its wild strain. The reaction conditions for prolonged reaction and process parameters for the conversion of 3-cyanopyridine to nicotinamide were optimized. Under the optimized reaction conditions the mutant 4D is stable at higher temperature (55°C, high ionic strength (0.3 M and at acidic pH conditions (5.5 and exhibited 8.0, 7.9 and 7.0 U/mg dcw NHase activity, respectively. In a batch reaction of (One litre, 7M 3-cyanopyridine was completely converted to nicotinamide in 3h at 55°C using 7g resting cells (dry cell mass of mutant 4D of R. rhodochrous PA-34.

  4. Protoplast fusion technology for improved production of coenzyme Q10 using Paracoccus denitrificans ATCC 19367 mutant strains

    Directory of Open Access Journals (Sweden)

    Pradipta Tokdar

    2014-01-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Induced mutants generated from Paracoccus denitrificans ATCC 19367 having antibiotic resistant markers, were used as parent strains to carry out protoplast fusion. The generated fusants were screened using standardized protocol for CoQ10 production. Among the generated fusants, one fusant namely PF-P1 showed 1.73 folds enhancements in specific CoQ10 content than wild type strain. Fusant PF-P1 was characterized by biochemical and molecular approaches where it showed differences than wild type strain. The fusant was further identified by 16S rRNA gene sequence analysis that showed eight nucleotide base pair mutation on conserved region and 99% homology with Paracoccus denitrificans strains. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  5. ADA APA DENGAN MENOPAUSE ?

    Directory of Open Access Journals (Sweden)

    Nuryati Atamimi

    2015-09-01

    Full Text Available Sebagai konselor yang menaruh minat pada berbagai masalah perkawinan, kondisi psikologis isteri yang akan, sedang ataupun setelah mengalami menopause menempati prosentase yang cukup banyak memberikan kontribusi bagi timbulnya masalah dari keseluruhan masalah yang dihadapi . Rasa cemas, tidak berdaya, sedih, cemburu, marah, dan berbagai perasaan tidak nyaman muncul pada usia itu dan biasanya selalu disertai dengan berbagai keluhan fisik seperti rematik, jantung berdebar, lemas, pusing, bermasalah dengan tekanan darah, gula darah, kolesterol, asam urat dan lain-lain. Mengapa hal ini terjadi, ada apa dengan menopause?

  6. DNA polymorphism and total protein in mutants of Metarhizium anisopliae var. Anisopliae (Metsch.) Sorokin strain E9 Polimorfismo de DNA e proteína total em mutantes da linhagem E9 de Metarhizium anisopliae var. anisopliae (Metsch.) Sorokin

    OpenAIRE

    Laurineide Lopes de Carvalho Freire; Ana Bolena Lima da Costa; Larissa Brandão Góes; Neiva Tinti de Oliveira

    2001-01-01

    Five mutants (MaE10, MaE27, MaE24, MaE41 e MaE49) of Metarhizium anisopliae wild strain E9 were analysed for DNA profile through the RAPD technique and for changes in total protein content by spectrophotometry, polyacrylamide gel electrophoresis and densitometry. The pattern of RAPD markers showed genetic polymorphism among the strains: out of twenty primers seven were selected, producing 113 bands. Forty seven bands were present in all strains (41.6% of monomorphic bands) and 66 showed polym...

  7. Complementation of Escherichia coli unc mutant strains by chloroplast and cyanobacterial F1-ATPase subunits.

    Science.gov (United States)

    Lill, H; Burkovski, A; Altendorf, K; Junge, W; Engelbrecht, S

    1993-10-04

    The genes encoding the five subunits of the F1 portion of the ATPases from both spinach chloroplasts and the cyanobacterium Synechocystis sp. PCC 6803 were cloned into expression vectors and expressed in Escherichia coli. The recombinant subunits formed inclusion bodies within the cells. Each particular subunit was expressed in the respective unc mutant, each unable to grow on non-fermentable carbon sources. The following subunits restored growth under conditions of oxidative phosphorylation: alpha (both sources, cyanobacterial subunit more than spinach subunit), beta (cyanobacterial subunit only), delta (both spinach and Synechocystis), and epsilon (both sources), whereas no growth was achieved with the gamma subunits from both sources. Despite a high degree of sequence homology the large subunits alpha and beta of spinach and cyanobacterial F1 were not as effective in the substitution of their E. coli counterparts. On the other hand, the two smallest subunits of the E. coli ATPase could be more effectively replaced by their cyanobacterial or chloroplast counterparts, although the sequence identity or even similarity is very low. We attribute these findings to the different roles of these subunits in F1: The large alpha and beta subunits contribute to the catalytic centers of the enzyme, a function rendering them very sensitive to even minor changes. For the smaller delta and epsilon subunits it was sufficient to maintain a certain tertiary structure during evolution, with little emphasis on the conservation of particular amino acids.

  8. Generation of stable mutants and targeted gene deletion strains in Cryptococcus neoformans through electroporation.

    Science.gov (United States)

    Lin, Xiaorong; Chacko, Nadia; Wang, Linqi; Pavuluri, Yashwant

    2015-04-01

    Cryptococcus neoformans is the etiologic agent of cryptococcal meningitis that causes more than half a million deaths worldwide each year. This capsulated basidiomycetous yeast also serves as a model for micropathogenic studies. The ability to make stable mutants, either via ectopic integration or homologous recombination, has been accomplished using biolistic transformation. This technical advance has greatly facilitated the research on the basic biology and pathogenic mechanisms of this pathogen in the past two decades. However, biolistic transformation is costly, and its reproducibility varies widely. Here we found that stable ectopic integration or targeted gene deletion via homologous replacement could be accomplished through electroporative transformation. The stability of the transformants obtained through electroporation and the frequency of homologous replacement is highly dependent on the selective marker. A frequency of homologous recombination among the stable transformants obtained by electroporation is comparable to those obtained by biolistic transformation (∼10%) when dominant drug selection markers are used, which is much higher than what has been previously reported for electroporation when auxotrophic markers were used (0.001% to 0.1%). Furthermore, disruption of the KU80 gene or generation of gene deletion constructs using the split marker strategy, two approaches known to increase homologous replacement among transformants obtained through biolistic transformation, also increase the frequency of homologous replacement among transformants obtained through electroporation. Therefore, electroporation provides a low cost alternative for mutagenesis in Cryptococcus.

  9. Safety, efficacy and efficiency of laser-assisted IVF in subfertile mutant mouse strains

    Science.gov (United States)

    Li, Ming-Wen; Kinchen, Kristy L; Vallelunga, Jadine M; Young, Diana L; Wright, Kaleb D K; Gorano, Lisa N; Wasson, Katherine; Lloyd, K C Kent

    2013-01-01

    In the present report we studied the safety, efficacy and efficiency of using an infrared laser to facilitate IVF by assessing fertilization, development and birth rates after laser-zona drilling (LZD) in 30 subfertile genetically modified (GM) mouse lines. We determined that LZD increased the fertilization rate four to ten times that of regular IVF, thus facilitating the derivation of 26 of 30 (86.7%) GM mouse lines. Cryopreserved two-cell stage embryos derived by LZD-assisted IVF were recovered and developed to blastocysts in vitro at the same rate as frozen–thawed embryos derived by regular IVF. Surprisingly after surgical transfer to pseudopregnant recipients the birth rate of embryos derived by LZD-assisted IVF was significantly lower than that of embryos derived by regular IVF. However this result could be completely mitigated by the addition of 0.25 M sucrose to the culture medium during LZD which caused the oocyte to shrink in volume relative to the perivitelline space. By increasing the distance from the laser target site on the zona pellucida, we hypothesize that the hyperosmotic effect of sucrose reduced the potential for laser-induced cytotoxic thermal damage to the underlying oocytes. With appropriate preparation and cautious application, our results indicate that LZD-assisted IVF is a safe, efficacious and efficient assisted reproductive technology for deriving mutant mouse lines with male factor infertility and subfertility caused by sperm–zona penetration defects. PMID:23315689

  10. Halorhodopsin and photosensory behaviour in Halobacterium halobium mutant strain L-33

    Energy Technology Data Exchange (ETDEWEB)

    Traulich, B.; Wagner, G. (Botanisches Institut l der Justus-Liebig-Universitat, Giessen (Germany, F.R.)); Hildebrand, E.; Schimz, A. (Kernforschungsanlage Juelich G.m.b.H. (Germany, F.R.). Inst. fuer Neurobiologie); Lanyi, J.K. (California Univ., Irvine (USA))

    1983-05-01

    Halobacterium halobium, strain L-33, which is deficient in bacteriorhodopsin (BR) but synthesizes increased amounts of halorhodopsin (HR), responds to changes in fluence rate with visible light or with UV light. The observations support an earlier report that BR is not essential for photosensing in H. halobium. In the UV-range, changes in light intensity elicit the maximal response at lambda = 370 nm. In the visible range, changes in light intensity show the maximal response at lambda = 565 nm and a secondary peak at lambda = 590 nm. The latter corresponds to the absorption maximum of HR (lambdasub(max) = 588 nm). This light-energy converting retinal pigment of H. halobium thus appears to contribute to photosensory behavior.

  11. Construction of "Toxin Complex" in a Mutant Serotype C Strain of Clostridium botulinum Harboring a Defective Neurotoxin Gene.

    Science.gov (United States)

    Suzuki, Tomonori; Nagano, Thomas; Niwa, Koichi; Uchino, Masataka; Tomizawa, Motohiro; Sagane, Yoshimasa; Watanabe, Toshihiro

    2017-01-01

    A non-toxigenic mutant of the toxigenic serotype C Clostridium botulinum strain Stockholm (C-St), C-N71, does not produce the botulinum neurotoxin (BoNT). However, the original strain C-St produces botulinum toxin complex, in which BoNT is associated with non-toxic non-hemagglutinin (NTNHA) and three hemagglutinin proteins (HA-70, HA-33, and HA-17). Therefore, in this study, we aimed to elucidate the effects of bont gene knockout on the formation of the "toxin complex." Nucleotide sequence analysis revealed that a premature stop codon was introduced in the bont gene, whereas other genes were not affected by this mutation. Moreover, we successfully purified the "toxin complex" produced by C-N71. The "toxin complex" was identified as a mixture of NTNHA/HA-70/HA-17/HA-33 complexes with intact NTNHA or C-terminally truncated NTNHA, without BoNT. These results indicated that knockout of the bont gene does not affect the formation of the "toxin complex." Since the botulinum toxin complex has been shown to play an important role in oral toxin transport in the human and animal body, a non-neurotoxic "toxin complex" of C-N71 may be valuable for the development of an oral drug delivery system.

  12. Monitoring the effect of pyrene on the germination and radial growth of the wild and mutant strains of Rhizopus arrhizus UCP402

    Directory of Open Access Journals (Sweden)

    Ricardo Kenji Shiosaki

    2008-06-01

    Full Text Available The physiological mutant of Rhizopus arrhizus was obtained in the pyrene resistance gradient test. Comparative studies were carried out about the behavior of the germination process and the radial growth of the mutant and wild strains of R. arrhizus UCP 402. Sabouraud Sucrose and Yeast Malt Broth cultures containing pyrene (10 mg/L induced the germination process of the sporangiospores of the wild and mutant strains of R. arrhizus. The radial growth of the strains was inversely proportional to the pyrene concentration in the culture medium. The results showed an adaptation of R. arrhizus UCP 402x (mutant in the pyrene (50mg/L and suggested a higher ability of application in the removal of pyrene from the contaminated areas.O mutante fisiológico de Rhizopus arrhizus foi obtido pelo teste do gradiente de resistência ao pireno. Estudos comparativos conduzidos sobre o comportamento do processo de germinação e o crescimento radial foram realizados entre as amostras selvagem e mutante de R. arrhizus UCP 402. Os meios Sabouraud Sacarose e Caldo de Levedura e Malte contendo pireno (10 mg/L induziram ao processo de germinação de esporangiosporos das amostras selvagem e mutante de R. arrhizus. O crescimento radial das amostras foi inversamente proporcional à concentração de pireno no meio de cultura. Os resultados demonstraram uma excelente adaptação da amostra mutante de R. arrhizus UCP 402x na concentração de pireno (50 mg/L, sugerindo uma alta habilidade e possibilidade de aplicação na remoção de pireno em áreas contaminadas.

  13. Characterization of the Burkholderia mallei tonB Mutant and Its Potential as a Backbone Strain for Vaccine Development.

    Science.gov (United States)

    Mott, Tiffany M; Vijayakumar, Sudhamathi; Sbrana, Elena; Endsley, Janice J; Torres, Alfredo G

    2015-01-01

    In this study, a Burkholderia mallei tonB mutant (TMM001) deficient in iron acquisition was constructed, characterized, and evaluated for its protective properties in acute inhalational infection models of murine glanders and melioidosis. Compared to the wild-type, TMM001 exhibits slower growth kinetics, siderophore hyper-secretion and the inability to utilize heme-containing proteins as iron sources. A series of animal challenge studies showed an inverse correlation between the percentage of survival in BALB/c mice and iron-dependent TMM001 growth. Upon evaluation of TMM001 as a potential protective strain against infection, we found 100% survival following B. mallei CSM001 challenge of mice previously receiving 1.5 x 10(4) CFU of TMM001. At 21 days post-immunization, TMM001-treated animals showed significantly higher levels of B. mallei-specific IgG1, IgG2a and IgM when compared to PBS-treated controls. At 48 h post-challenge, PBS-treated controls exhibited higher levels of serum inflammatory cytokines and more severe pathological damage to target organs compared to animals receiving TMM001. In a cross-protection study of acute inhalational melioidosis with B. pseudomallei, TMM001-treated mice were significantly protected. While wild type was cleared in all B. mallei challenge studies, mice failed to clear TMM001. Although further work is needed to prevent chronic infection by TMM001 while maintaining immunogenicity, our attenuated strain demonstrates great potential as a backbone strain for future vaccine development against both glanders and melioidosis.

  14. Characterization of the Burkholderia mallei tonB Mutant and Its Potential as a Backbone Strain for Vaccine Development.

    Directory of Open Access Journals (Sweden)

    Tiffany M Mott

    Full Text Available In this study, a Burkholderia mallei tonB mutant (TMM001 deficient in iron acquisition was constructed, characterized, and evaluated for its protective properties in acute inhalational infection models of murine glanders and melioidosis.Compared to the wild-type, TMM001 exhibits slower growth kinetics, siderophore hyper-secretion and the inability to utilize heme-containing proteins as iron sources. A series of animal challenge studies showed an inverse correlation between the percentage of survival in BALB/c mice and iron-dependent TMM001 growth. Upon evaluation of TMM001 as a potential protective strain against infection, we found 100% survival following B. mallei CSM001 challenge of mice previously receiving 1.5 x 10(4 CFU of TMM001. At 21 days post-immunization, TMM001-treated animals showed significantly higher levels of B. mallei-specific IgG1, IgG2a and IgM when compared to PBS-treated controls. At 48 h post-challenge, PBS-treated controls exhibited higher levels of serum inflammatory cytokines and more severe pathological damage to target organs compared to animals receiving TMM001. In a cross-protection study of acute inhalational melioidosis with B. pseudomallei, TMM001-treated mice were significantly protected. While wild type was cleared in all B. mallei challenge studies, mice failed to clear TMM001.Although further work is needed to prevent chronic infection by TMM001 while maintaining immunogenicity, our attenuated strain demonstrates great potential as a backbone strain for future vaccine development against both glanders and melioidosis.

  15. ARE: Ada Rendering Engine

    Directory of Open Access Journals (Sweden)

    Stefano Penge

    2009-10-01

    Full Text Available E' ormai pratica diffusa, nello sviluppo di applicazioni web, l'utilizzo di template e di potenti template engine per automatizzare la generazione dei contenuti da presentare all'utente. Tuttavia a volte la potenza di tali engine è€ ottenuta mescolando logica e interfaccia, introducendo linguaggi diversi da quelli di descrizione della pagina, o addirittura inventando nuovi linguaggi dedicati.ARE (ADA Rendering Engine è€ pensato per gestire l'intero flusso di creazione del contenuto HTML/XHTML dinamico, la selezione del corretto template, CSS, JavaScript e la produzione dell'output separando completamente logica e interfaccia. I templates utilizzati sono puro HTML senza parti in altri linguaggi, e possono quindi essere gestiti e visualizzati autonomamente. Il codice HTML generato è€ uniforme e parametrizzato.E' composto da due moduli, CORE (Common Output Rendering Engine e ALE (ADA Layout Engine.Il primo (CORE viene utilizzato per la generazione OO degli elementi del DOM ed è pensato per aiutare lo sviluppatore nella produzione di codice valido rispetto al DTD utilizzato. CORE genera automaticamente gli elementi del DOM in base al DTD impostato nella configurazioneIl secondo (ALE viene utilizzato come template engine per selezionare automaticamente in base ad alcuni parametri (modulo, profilo utente, tipologia del nodo, del corso, preferenze di installazione il template HTML, i CSS e i file JavaScript appropriati. ALE permette di usare templates di default e microtemplates ricorsivi per semplificare il lavoro del grafico.I due moduli possono in ogni caso essere utilizzati indipendentemente l'uno dall'altro. E' possibile generare e renderizzare una pagina HTML utilizzando solo CORE oppure inviare gli oggetti CORE al template engine ALE che provvede a renderizzare la pagina HTML. Viceversa è possibile generare HTML senza utilizzare CORE ed inviarlo al template engine ALECORE è alla prima release ed è€ già utilizzato all

  16. An attenuated Shigella mutant lacking the RNA-binding protein Hfq provides cross-protection against Shigella strains of broad serotype.

    Science.gov (United States)

    Mitobe, Jiro; Sinha, Ritam; Mitra, Soma; Nag, Dhrubajyoti; Saito, Noriko; Shimuta, Ken; Koizumi, Nobuo; Koley, Hemanta

    2017-07-01

    Few live attenuated vaccines protect against multiple serotypes of bacterial pathogen because host serotype-specific immune responses are limited to the serotype present in the vaccine strain. Here, immunization with a mutant of Shigella flexneri 2a protected guinea pigs against subsequent infection by S. dysenteriae type 1 and S. sonnei strains. This deletion mutant lacked the RNA-binding protein Hfq leading to increased expression of the type III secretion system via loss of regulation, resulting in attenuation of cell viability through repression of stress response sigma factors. Such increased antigen production and simultaneous attenuation were expected to elicit protective immunity against Shigella strains of heterologous serotypes. Thus, the vaccine potential of this mutant was tested in two guinea pig models of shigellosis. Animals vaccinated in the left eye showed fewer symptoms upon subsequent challenge via the right eye, and even survived subsequent intestinal challenge. In addition, oral vaccination effectively induced production of immunoglobulins without severe side effects, again protecting all animals against subsequent intestinal challenge with S. dysenteriae type 1 or S. sonnei strains. Antibodies against common virulence proteins and the O-antigen of S. flexneri 2a were detected by immunofluorescence microscopy. Reaction of antibodies with various strains, including enteroinvasive Escherichia coli, suggested that common virulence proteins induced protective immunity against a range of serotypes. Therefore, vaccination is expected to cover not only the most prevalent serotypes of S. sonnei and S. flexneri 2a, but also various Shigella strains, including S. dysenteriae type 1, which produces Shiga toxin.

  17. Ada for multi-microprocessors

    Energy Technology Data Exchange (ETDEWEB)

    Tedd, M.; Crespi-Reghizzi, S.; Natali, A.

    1984-01-01

    This book presents papers on the use of the Ada programming language in array processors. Topics considered include distributed data processing, examples of distributed systems, requirements for the programming language and tools, the suitability of Ada and Apse, strategies for developing distributed systems, the construction system, reliability and extensibility, and the MML programming language.

  18. The AdaBoost Flow

    CERN Document Server

    Lykov, A; Vaninsky, K

    2011-01-01

    We introduce a dynamical system which we call the AdaBoost flow. The flow is defined by a system of ODEs with control. We show how by a suitable choice of control AdaBoost algorithm of Schapire and Freund and arc-gv algorithm of Breiman can be embedded in the AdaBoost flow. We also show how previously studied by Schapire and Singer confidence rated prediction can be obtained from our continuous time approach. We introduce a new continuous time algorithm which we call superBoost and describe its properties. The AdaBoost flow equations coincide with the equations of dynamics of the nonperiodic Toda system written in terms of spectral variables. This establishes a connection between two seemingly unrelated fields of boosting algorithms and classical integrable models. Finally we explain similarity of the AdaBoost flow with Perelman's ideas to control Ricci flow.

  19. Growth of catalase A and catalase T deficient mutant strains of Saccharomyces cerevisiae on ethanol and oleic acid : Growth profiles and catalase activities in relation to microbody proliferation

    NARCIS (Netherlands)

    Klei, Ida J. van der; Rytka, Joanna; Kunau, Wolf H.; Veenhuis, Marten

    1990-01-01

    The parental strain (A+T+) of Saccharomyces cerevisiae and mutants, deficient in catalase T (A+T-), catalase A (A-T+) or both catalases (A-T-), grew on ethanol and oleic acid with comparable doubling times. Specific activities of catalase were low in glucose- and ethanol-grown cells. In the two olei

  20. Inactivation of ccmO in Synechococcus sp. Strain PCC 7942 Results in a Mutant Requiring High Levels of CO(2).

    Science.gov (United States)

    Marco, E; Martinez, I; Ronen-Tarazi, M; Orus, M I; Kaplan, A

    1994-03-01

    Inactivation of ccmO in Synechococcus sp. strain PCC 7942 resulted in a mutant which possesses aberrant carboxysomes and a normal inorganic carbon uptake capability but a reduced ability to photosynthetically utilize the internal inorganic carbon pool. Consequently, it exhibits low apparent photosynthetic affinity for extracellular inorganic carbon and demands high levels of CO(2) for growth.

  1. Draft Genome Sequences of Two Heat-Resistant Mutant Strains (A52 and B41) of the Photosynthetic Hydrogen-Producing Bacterium Rhodobacter capsulatus

    Science.gov (United States)

    Gokce, Abdulmecit; Cakar, Zeynep Petek; Yucel, Meral; Ozcan, Orhan; Sencan, Sevde; Sertdemir, Ibrahim; Erguner, Bekir; Yuceturk, Betul; Sarac, Aydan; Yuksel, Bayram

    2016-01-01

    The draft genome sequences of two heat-resistant mutant strains, A52 and B41, derived from Rhodobacter capsulatus DSM 1710, and with different hydrogen production levels, are reported here. These sequences may help understand the molecular basis of heat resistance and hydrogen production in R. capsulatus. PMID:27284151

  2. A mutant lacking the glutamine synthetase gene (glnA) is impaired in the regulation of the nitrate assimilation system in the cyanobacterium Synechocystis sp. strain PCC 6803.

    Science.gov (United States)

    Reyes, J C; Florencio, F J

    1994-12-01

    The existence in the unicellular cyanobacterium Synechocystis sp. strain PCC 6803 of two genes (glnA and glnN) coding for glutamine synthetase (GS) has been recently reported (J.C. Reyes and F.J. Florencio, J. Bacteriol. 176:1260-1267, 1994). In the current work, the regulation of the nitrate assimilation system was studied with a glnA-disrupted Synechocystis mutant (strain SJCR3) in which the only GS activity is that corresponding to the glnN product. This mutant was unable to grow in ammonium-containing medium because of its very low levels of GS activity. In the SJCR3 strain, nitrate and nitrite reductases were not repressed by ammonium, and short-term ammonium-promoted inhibition of nitrate uptake was impaired. In Synechocystis sp. strain PCC 6803, nitrate seems to act as a true inducer of its assimilation system, in a way similar to that proposed for the dinitrogen-fixing cyanobacteria. A spontaneous derivative strain from SJCR3 (SJCR3.1), was able to grow in ammonium-containing medium and exhibited a fourfold-higher level of GS activity than but the same amount of glnN transcript as its parental strain (SJCR3). Taken together, these finding suggest that SJCR3.1 is a mutant affected in the posttranscriptional regulation of the GS encoded by glnN. This strain recovered regulation by ammonium of nitrate assimilation. SJCR3 cells were completely depleted of intracellular glutamine shortly after addition of ammonium to cells growing with nitrate, while SJCR3.1 cells maintained glutamine levels similar to that reached in the wild-type Synechocystis sp. strain PCC 6803. Our results indicate that metabolic signals that control the nitrate assimilation system in Synechocystis sp. strain PCC 6803 require ammonium metabolism through GS.

  3. Booster vaccination with safe, modified, live-attenuated mutants of Brucella abortus strain RB51 vaccine confers protective immunity against virulent strains of B. abortus and Brucella canis in BALB/c mice.

    Science.gov (United States)

    Truong, Quang Lam; Cho, Youngjae; Kim, Kiju; Park, Bo-Kyoung; Hahn, Tae-Wook

    2015-11-01

    Brucella abortus attenuated strain RB51 vaccine (RB51) is widely used in prevention of bovine brucellosis. Although vaccination with this strain has been shown to be effective in conferring protection against bovine brucellosis, RB51 has several drawbacks, including residual virulence for animals and humans. Therefore, a safe and efficacious vaccine is needed to overcome these disadvantages. In this study, we constructed several gene deletion mutants (ΔcydC, ΔcydD and ΔpurD single mutants, and ΔcydCΔcydD and ΔcydCΔpurD double mutants) of RB51 with the aim of increasing the safety of the possible use of these mutants as vaccine candidates. The RB51ΔcydC, RB51ΔcydD, RB51ΔpurD, RB51ΔcydCΔcydD and RB51ΔcydCΔpurD mutants exhibited significant attenuation of virulence when assayed in murine macrophages in vitro or in BALB/c mice. A single intraperitoneal immunization with RB51ΔcydC, RB51ΔcydD, RB51ΔcydCΔcydD or RB51ΔcydCΔpurD mutants was rapidly cleared from mice within 3 weeks, whereas the RB51ΔpurD mutant and RB51 were detectable in spleens until 4 and 7 weeks, respectively. Vaccination with a single dose of RB51 mutants induced lower protective immunity in mice than did parental RB51. However, a booster dose of these mutants provided significant levels of protection in mice against challenge with either the virulent homologous B. abortus strain 2308 or the heterologous Brucella canis strain 26. In addition, these mutants were found to induce a mixed but T-helper-1-biased humoral and cellular immune response in immunized mice. These data suggest that immunization with a booster dose of attenuated RB51 mutants provides an attractive strategy to protect against either bovine or canine brucellosis.

  4. Influence of pH on butyrate uptake and solvent fermentation by a mutant strain of Clostridium acetobutylicum

    Energy Technology Data Exchange (ETDEWEB)

    Soni, B.K. [Institute of Gas Technology, 1700 S. Mount Prospect Road, Des Plaines, IL 60018 (United States); Jain, M.K. [MBI International, P.O. Box 27609, 3900 Collins Road, Lansing, MI 48909 (United States)

    1997-11-01

    The effect of pH (between 4.4 and 6.6) on butyrate uptake by the mutant strain of Clostridium acetobutylicum was studied using the fermentation broth from fermentor-2 (solventogenic stage) of a two-fermentor continuous system. Low pH (< 4.6) adversely affected the overall metabolic activity as observed by low solvent production and carbohydrate consumption. Uptake of 4.0 {+-} 0.5 g l{sup -1} butyrate, under batch incubation at 30 C, was not inhibited at pH > 5.2, however, at pH < 5.2, a marked inhibition in butyrate uptake was noticed. A higher pH (e.g. pH 5.4) was required for the uptake of elevated concentration of externally added butyrate at 8.5 {+-} 1.0 g l{sup -1}. Batch incubation at relatively higher temperatures (35 and 37 C) indicated a similar trend i.e., a pH of >5.5 was required for uptake of >8 g l{sup -1} butyrate. Optimization studies for butyrate uptake by C. acetobutylicum suggested a direct correlation between minimum pH and butyrate concentration or temperature. The role of undissociated butyric acid appears to be critical in regulation of butyrate uptake. (orig.) With 5 figs., 6 tabs., 23 refs.

  5. Increase Hydrogen Production by Hydrogen-producing Mutant UV-d48 in Comparison with Wild Parent Strain Etanoligenens sp ZGX4

    Institute of Scientific and Technical Information of China (English)

    ZHENG Guo-xiang; REN Nan-qi; LIN Hai-long; LI Yong-feng

    2006-01-01

    Hydrogen production by hydrogen-producing mutant strain UV-d48 was one typical ethanol-type fermentative H2-producing mutant, which the main metabolic end production was ethanol and acetic acid. Compare to the wild type strain, the activity of hydrogenase of mutant UV-d48 was stronger in course of growth and fermentation. It can evolve hydrogen at stronger ability and a greater rate than that of its parent wild type, namely ZGX4. Resting cells of UVd48 and Ethanoligenens sp ZGX4 were set up in a batch mode in phosphate buffered saline (PBS) to decouple growth from hydrogen production at the expense of glucose of varying composition. Mutant UV-d48 evolved more hydrogen than ZGX4at glucose concentrations ranging from 2 mmol/L to 200 mmol/L. The difference in the amount of H2 evolved by both strains decreased as the concentration of glucose increased. The maximal H2 yield and H2-producing rate by strain UV-d48 was 3091.1 mL/L and 54 mL/(hODunitL) respectively, at a glucose concentration of 60 mmol/L. With strain ZGX4, the maximal H2 yield and H2-producing rate was 2 180.2 mL/L and 33 mL/(hODunitL) under these conditions, respectively.Experiments using wastewater with certain content molasses yielded similar results. In each case, strain UV-d48 evolved hydrogen at a faster rate than the wild type, showing a possible potential for commercial hydrogen production.

  6. Detection of Mycoplasma mycoides subsp. mycoides SC in bronchoalveolar lavage fluids of cows based on a TaqMan real-time PCR discriminating wild type strains from an lppQ− mutant vaccine strain used for DIVA-strategies

    Science.gov (United States)

    Vilei, Edy M.; Frey, Joachim

    2010-01-01

    Contagious bovine pleuropneumonia (CBPP) is the most serious cattle disease in Africa, caused by Mycoplasma mycoides subsp. mycoides small-colony type (SC). CBPP control strategies currently rely on vaccination with a vaccine based on live attenuated strains of the organism. Recently, an lppQ− mutant of the existing vaccine strain T1/44 has been developed (Janis et al., 2008). This T1lppQ− mutant strain is devoid of lipoprotein LppQ, a potential virulence attribute of M. mycoides subsp. mycoides SC. It is designated as a potential live DIVA (Differentiating Infected from Vaccinated Animals) vaccine strain allowing both serological and etiological differentiation. The present paper reports on the validation of a control strategy for CBPP in cattle, whereby a TaqMan real-time PCR based on the lppQ gene has been developed for the direct detection of M. mycoides subsp. mycoides SC in ex vivo bronchoalveolar lavage fluids of cows and for the discrimination of wild type strains from the lppQ− mutant vaccine strain. PMID:20381545

  7. Ada Linear-Algebra Program

    Science.gov (United States)

    Klumpp, A. R.; Lawson, C. L.

    1988-01-01

    Routines provided for common scalar, vector, matrix, and quaternion operations. Computer program extends Ada programming language to include linear-algebra capabilities similar to HAS/S programming language. Designed for such avionics applications as software for Space Station.

  8. Ada Linear-Algebra Program

    Science.gov (United States)

    Klumpp, A. R.; Lawson, C. L.

    1988-01-01

    Routines provided for common scalar, vector, matrix, and quaternion operations. Computer program extends Ada programming language to include linear-algebra capabilities similar to HAS/S programming language. Designed for such avionics applications as software for Space Station.

  9. DNA polymorphism and total protein in mutants of Metarhizium anisopliae var. Anisopliae (Metsch. Sorokin strain E9 Polimorfismo de DNA e proteína total em mutantes da linhagem E9 de Metarhizium anisopliae var. anisopliae (Metsch. Sorokin

    Directory of Open Access Journals (Sweden)

    Laurineide Lopes de Carvalho Freire

    2001-06-01

    Full Text Available Five mutants (MaE10, MaE27, MaE24, MaE41 e MaE49 of Metarhizium anisopliae wild strain E9 were analysed for DNA profile through the RAPD technique and for changes in total protein content by spectrophotometry, polyacrylamide gel electrophoresis and densitometry. The pattern of RAPD markers showed genetic polymorphism among the strains: out of twenty primers seven were selected, producing 113 bands. Forty seven bands were present in all strains (41.6% of monomorphic bands and 66 showed polymorphism (58.4%. The mean coefficient of similarity among all strains was 0.75 (75%. The total protein content varied, staining in the interval of 6.0-8.0 µg/µl. The electrophoresis analysis, through zymogram and protein fraction profiles by densitometry, allowed the observation of seven bands for the wild strain E9 and five bands for the mutants MaE10, MaE27, MaE34, MaE41 and MaE49, evidence of variations in µg% among protein fractions. The RAPD technique was very sensitive to detect genetic differences between the wild type and the mutants obtained through gamma radiation. The total protein analysis also showed changes in quantity and pattern of bands after electrophoresis in the mutants compared to the wild type.Foram analisados cinco mutantes MaE (MaE10, MaE27, MaE34, MaE41 e MaE49 da linhagem selvagem E9 de Metarhizium anisopliae var. anisopliae quanto ao perfil de DNA pela técnica de RAPD e também quanto ao conteúdo de proteína total por espectrometria e eletroforese em gel de poliacrilamida e densitometria. O padrão de marcadores de RAPD evidenciou polimorfismo nas amostras; dos 20 primers testados foram selecionados 7 que geraram 113 bandas. Deste total, 47 estavam presentes em todas as amostras (41.6% de bandas monomórficas e 66 mostraram polimorfismo (58.4%. O coeficiente médio de similaridade foi de 75%. O conteúdo de proteína total variou de 6 a 8 µg/µl. O zimograma e perfís das frações de proteínas obtidos por densitometria

  10. Paranoia.Ada: Sample output reports

    Science.gov (United States)

    1986-01-01

    Paranoia.Ada is a program to diagnose floating point arithmetic in the context of the Ada programming language. The program evaluates the quality of a floating point arithmetic implementation with respect to the proposed IEEE Standards P754 and P854. Paranoia.Ada is derived from the original BASIC programming language version of Paranoia. The Paranoia.Ada replicates in Ada the test algorithms originally implemented in BASIC and adheres to the evaluation criteria established by W. M. Kahan. Paranoia.Ada incorporates a major structural redesign and employs applicable Ada architectural and stylistic features.

  11. Isolation of an Escherichia coli K-12 mutant strain able to form biofilms on inert surfaces: involvement of a new ompR allele that increases curli expression.

    Science.gov (United States)

    Vidal, O; Longin, R; Prigent-Combaret, C; Dorel, C; Hooreman, M; Lejeune, P

    1998-05-01

    Classical laboratory strains of Escherichia coli do not spontaneously colonize inert surfaces. However, when maintained in continuous culture for evolution studies or industrial processes, these strains usually generate adherent mutants which form a thick biofilm, visible with the naked eye, on the wall of the culture apparatus. Such a mutant was isolated to identify the genes and morphological structures involved in biofilm formation in the very well characterized E. coli K-12 context. This mutant acquired the ability to colonize hydrophilic (glass) and hydrophobic (polystyrene) surfaces and to form aggregation clumps. A single point mutation, resulting in the replacement of a leucine by an arginine residue at position 43 in the regulatory protein OmpR, was responsible for this phenotype. Observations by electron microscopy revealed the presence at the surfaces of the mutant bacteria of fibrillar structures looking like the particular fimbriae described by the Olsén group and designated curli (A. Olsén, A. Jonsson, and S. Normark, Nature 338:652-655, 1989). The production of curli (visualized by Congo red binding) and the expression of the csgA gene encoding curlin synthesis (monitored by coupling a reporter gene to its promoter) were significantly increased in the presence of the ompR allele described in this work. Transduction of knockout mutations in either csgA or ompR caused the loss of the adherence properties of several biofilm-forming E. coli strains, including all those which were isolated in this work from the wall of a continuous culture apparatus and two clinical strains isolated from patients with catheter-related infections. These results indicate that curli are morphological structures of major importance for inert surface colonization and biofilm formation and demonstrate that their synthesis is under the control of the EnvZ-OmpR two-component regulatory system.

  12. Growth phase effect on the dark anaerobic hydrogen production in the glucose tolerant mutant of unicellular cyanobacterium Synechocystis sp. strain PCC6803

    Directory of Open Access Journals (Sweden)

    Adipa Chongsuksantikul*

    2015-04-01

    Full Text Available This study has examined the effect of growth phase on hydrogenproduction from cells of a glucose tolerant mutant of Synechocystissp. strain PCC6803. The extracellular products including hydrogen,lactate and acetate from cyanobacteria cells in dark anaerobicnitrate-free solution, yielded different excretory profiles dependingon which growth phases were prepared from photosynthesis. Theamount of hydrogen generated cells prepared from stationary phasewas highest in HEPES buffer and nitrate-free solution, darkanaerobic condition.

  13. Comparative Evaluation of Agroindustrial Byproducts for the Production of Alkaline Protease by Wild and Mutant Strains of Bacillus subtilis in Submerged and Solid State Fermentation

    OpenAIRE

    Hamid Mukhtar; Ikramul Haq

    2013-01-01

    The present study describes the screening of different agroindustrial byproducts for enhanced production of alkaline protease by a wild and EMS induced mutant strain of Bacillus subtilis IH-72EMS8. During submerged fermentation, different agro-industrial byproducts were tested which include defatted seed meals of rape, guar, sunflower, gluten, cotton, soybean, and gram. In addition to these meals, rice bran, wheat bran, and wheat flour were also evaluated for protease production. Of all the b...

  14. Ada Implementation Guide. Software Engineering With Ada. Volume 1

    Science.gov (United States)

    1994-04-01

    teaching, the student is less likely to readily adopt new, more powerful ways of accomplishing old tasks 122 Depatn of the NaY I ! Trablng and Educaion and...Maturity Model3 (CMU/SEI-92-TR-25, ESC-TR-/92-0M5). Pittsburgh, PA : Carnegie-Mellon University, 1992. SBoehm. B.W. Software Engineering Economics...Pittsburgh, PA : Carnegie-Mellon University, 19-21 March 1991. £ Contrast: Ada 9X and C++, Schonberg, E. New York University, 1992 (Distributed by Ada IC on

  15. Comparison of wild-type and UV-mutant beta-glucanase-producing strains of Talaromyces emersonii with potential in brewing applications.

    Science.gov (United States)

    McCarthy, Tracey C; Lalor, Eoin; Hanniffy, Orla; Savage, Angela V; Tuohy, Maria G

    2005-04-01

    A screen of 46 UV-mutant strains of the moderately thermophilic fungus Talaromyces emersonii yielded two mutants (TC2, TC5) that displayed gross morphological differences to the parent strain and enhanced activity against mixed linkage cereal beta-glucans. Activity against beta-(1, 3)(1, 4)-D: -glucan from barley (BBGase) was measured during growth of the mutant and wild-type strains on a variety of carbon sources, ranging from solka floc to crude cereal fractions. In liquid culture, TC2 and TC5 secreted 1.2- to 8.6-fold more BBGase than the parent strain and markedly less beta-glucosidase (exo-activity); enzyme levels were dependent on the carbon source. Cellulose induced high BBGase. However, beet pulp, wheat bran, carob and tea-leaves were cheap and effective inducers. T. emersonii wild-type, TC2 and TC5 crude enzyme preparations achieved similar end-points during the hydrolysis of commercial barley beta-glucan (13.0-16.9%), but were more active against crude beta-glucan from barley (16.0-24.2% hydrolysis). The products of hydrolysis were quantified by high-performance anion-exchange chromatography. Mash trials indicated that enzyme preparations from all three organisms effected a significant reduction in wort viscosity and residual mash beta-glucan. Finally, TC2 and TC5 produce more efficient beta-glucan-depolymerizing enzymes; and wheat bran and solka floc can be used to provide inexpensive and potent enzyme cocktails with potential in brewing applications.

  16. Ada Compiler Validation Summary Report: ROLM Ada Compiler, Version 4.42 V-002.

    Science.gov (United States)

    1983-05-12

    EC =3 CB3003A-B.ADA P SC =64 CB3004A.ADA P SCz 52 BB3005A.ADA P SC= 4 EC z2 CB4001A..ADA P SC 60 C84002A.ADA P SCx 50 C34003A-AB.AOA P SC =35...a class B test is indicated by EC. The results for each test file were as follows: B22001A.TST PS SC : 26 EC s 8 B22001B.TST PS SCx 8 EC- 3...A29002F-B.ADA P -Sc z1Il A29002G-B.ADA P SC z88 A29002I-.B.ADA P SC = 63 A29002I-8B.ADA P SC= 95 A29002J-B.ADA P SC 81 D29002K-B.ADA P SCz 766 *B32103A

  17. A new osteopetrosis mutant mouse strain (ntl) with odontoma-like proliferations and lack of tooth roots.

    Science.gov (United States)

    Lu, Xincheng; Rios, Hector F; Jiang, Baichun; Xing, Lianping; Kadlcek, Renata; Greenfield, Edward M; Luo, Guangbin; Feng, Jian Q

    2009-12-01

    A new spontaneous mouse mutant (ntl) with autosomal-recessive osteopetrosis was characterized. These mice formed tartrate-resistant acid phosphate (TRAP)-positive osteoclasts but their osteoclasts had no ruffled border and did not resorb bone. These mice displayed no tooth eruption or tooth root formation. Adult mutant mice developed odontoma-like proliferations near the proximal ends of the incisors. Intraperitoneal injection of progenitor cells from the liver of 16.5 days postcoitum wild-type embryos into newborn mutants rescued the osteopetrosis phenotype, indicating that the defects were intrinsic to the osteoclasts. Our findings not only provide further support for a critical role of osteoclasts in tooth eruption and tooth root development, but also suggest that the perturbation of the homeostasis of the odontogenic precursors of the incisors is primarily responsible for the development of the odontoma-like proliferations in this osteopetrosis mutant. Genetic mapping has narrowed down the location of the mutant allele to a genetic interval of 3.2 cM on mouse chromosome 17.

  18. Technical Report on the Development of Mutant Paracoccus strain and Optimization of Medium Composition for the Mass Production of Astaxanthin

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Il; Lee, Ju Woon; Kim, Jae Hun; Song, Beom Seok

    2010-08-15

    Astaxanthin is used to role of provitamin A, and it is stronger antioxidant activity than vitamin E (100-500 times higher activity) and other carotenoids (10-fold). Furthermore, astaxanthin is also used as a nutraceutical and a medicinal ingredient against degenerative diseases such as cancer, heart disease, and skin related illness. The objective of this study was develop a carotenoid-hyperproducing mutant of Paracoccus N81106 using gamma irradiation and optimized medium composition. A mutant of Paracoccus having higher carotenoid content was isolated, and the production medium was optimized using response surface methodology. These results support that astaxanthin with strong antioxidant activity could be economically produced using the mutant and will be helpful for the related industry

  19. Computational studies on the resistance of penicillin-binding protein 2B (PBP2B) of wild-type and mutant strains of Streptococcus pneumoniae against β-lactam antibiotics.

    Science.gov (United States)

    Ramalingam, Jothi; Vennila, Jannet; Subbiah, Parthasarathy

    2013-09-01

    Mutations within transpeptidase domain of penicillin-binding protein 2B of the strains of Streptococcus pneumoniae leads to resistance against β-lactam antibiotics. To uncover the important residues responsible for sensitivity and resistance, the recently determined three dimensional structures of penicillin-binding protein 2B of both wild-type R6 (sensitive) and mutant 5204 (resistant) strains along with the predicted structures of other mutant strains G54, Hungary19A-6 and SP195 were considered for the interaction study with β-lactam antibiotics using induced-fit docking of Schrödinger. Associated binding energies of the complexes and their intermolecular interactions in the binding site clearly show that the wild-type R6 as sensitive, mutant strains 5204 and G54 as highly resistant, and the mutant strains Hungary19A-6 and SP195 as intermediate resistant. The study also reveals that the mutant strains Hungary19A-6 and SP195 exhibit intermediate resistant because of the existence of mutations till the intermediate 538th and 516th positions, respectively, and not till the end of the C-terminus. Furthermore, our investigations show that if the mutations are extended till the end of the C terminus, then the antibiotic resistance of induced-mutated strains increases from intermediate to high as in the strains 5204 and G54. The binding patterns obtained in the study are useful in designing potential inhibitors against multidrug resistant S. pneumoniae.

  20. The Utility of Ada for Army Modeling

    Science.gov (United States)

    1990-04-10

    34 Ada " for Ada Lovelace (1815-1851), a mathematician who worked with Charles Babbage on his difference and analytic engines.9 Later in 1979, the HOLWG...OF ADA FOR ARMY MODELING BY COLONEL MICHAEL L. YOCOM DISTRIBUTION STATEMENT A: Approved for publie releases distribution is unlimited. 1% LF-, EC TE...TITLE (ad Subtitle) a. TYPE OF REPORT & PERIOD COVERED The Utility of Ada for Army Modeling Individual Study Project 6 PERFORMING ORG. REPORT NUMBER

  1. Substrate specificity of glucose dehydrogenase and carbon source utilization pattern of pantoea dispersa strain P2 and its radiation induced mutants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Keun; Murugesan, Senthilkumar [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2009-06-15

    Mineral phosphate solubilizing pantoea dispersa strain P2 produced 5.5 mM and 42.6 mM of gluconic acid on 24 h and 72 h incubation, respectively. Strain P2 exhibited glucose dehydrogenase (GDH) specific activity of 0.32 IU mg{sup -1} protein. We have studied the substrate specificity of GDH as well as carbon source utilization pattern of strain P2. GDH of strain P2 did not use ribose as substrate. Utilization of lactose with specific activity of 0.65 IU mg{sup -1} protein indicated that the enzyme belongs to GDH type B isozyme. Arabinose, galactose, ribose, sucrose and xylose did not induce the synthesis of GDH enzyme while mannose induced the synthesis of GDH with highest specific activity of 0.58 IU mg{sup -1} protein. Through radiation mutagenesis, the substrate specificity of GDH was modified in order to utilize side range of sugars available in root exudates. Ribose, originally not a substrate for GDH of strain P2 was utilized as substrate by mutants P2-M5 with specific activity of 0.44 and 0.57 IU mg{sup -1} protein, respectively. Specific activity of GDH on the media containing lactose and galactose was also improved to 1.2 and 0.52 IU mg{sup -1} protein in P2-M5 and P2-M6 respectively. Based on the carbon source availability in root exudate, the mutants can be selected and utilized as efficient biofertilizer under P-deficient soil conditions.

  2. Expression profiles of genes in wild-type DJ-1 and L10P mutant DJ-1 in monoclonal cell strains

    Directory of Open Access Journals (Sweden)

    LIU Zhen-hua

    2013-07-01

    Full Text Available Background DJ-1 gene is a causative gene which contributes to the onset of autosomal recessive early-onset parkinsonism (AREP. Many research suggest that DJ-1 protein may change expression of certain genes through regulate its transcriptional activity, which play a role in the pathogenesis of Parkinson's disease (PD. In our previous study, we found a new mutation of DJ-1 which we named as L10P. DJ-1 gene encodes the first frame 29 bp from the thymine (T→cytosine (C, so that the leucine on the 10th locus of DJ-1 protein was replaced by proline (L10P. To elucidate the effect of the L10P mutation, we identify genes for which expressions are abnormally regulated by L10P mutant DJ-1 protein using DNA microarray analysis. Methods Human embryonic kidney cell 293 (HEK293 monoclonal cell strains which can stably express pCMV-Tag2A-Flag, pCMV-Tag2A-Flag-DJ-1 and pCMV-Tag2A-Flag-DJ-1-L10P were selected by screening, and identified on the basis of DNA, RNA and protein levels to confirm whether the acquired HEK293 monoclonal cell strains can stably express empty vector, wild-type DJ-1 protein and L10P mutant DJ-1 protein. Gene chip technique was used to perform differential gene screening for different groups of HEK293 monoclonal cell strains. Results Compared with the expression in empty vector group, the expression of 14 genes was up-regulated and 28 genes was down-regulated in wild-type group; and the expression of 14 genes was up-regulated and 9 down-regulated in expressing L10P mutant group respectively. Comparison of the expression in wild-type group, expression of 59 genes was up-regulated and 27 genes down-regulated in L10P mutant group. These differential genes all took part in the biological processes including signal transduction, transcriptional regulation, cell cycle, apoptosis, oxidative stress and so on. Conclusion L10P mutant DJ-1 protein may directly or indirectly influence the singal transduction and play a role in the mechanism of PD.

  3. 2-DE based proteomic analysis of Saccharomyces cerevisiae wild and K+ transport-affected mutant (trk1,2) strains at the growth exponential and stationary phases.

    Science.gov (United States)

    Curto, Miguel; Valledor, Luis; Navarrete, Clara; Gutiérrez, Dolores; Sychrova, Hana; Ramos, José; Jorrin, Jesús

    2010-11-10

    By using a 2-DE based workflow, the proteome of wild and potassium transport mutant trk1,2 under optimal growth potassium concentration (50mM) has been analyzed. At the exponential and stationary phases, both strains showed similar growth, morphology potassium content, and Vmax of rubidium transport, the only difference found being the Km values for this potassium analogue transport, higher for the mutant (20mM) than for the wild (3-6mM) cells. Proteins were buffer-extracted, precipitated, solubilized, quantified, and subjected to 2-DE analysis in the 5-8 pH range. More differences in protein content (37-64mgg(-1) cell dry weight) and number of resolved spots (178-307) were found between growth phases than between strains. In all, 164 spots showed no differences between samples and a total of 105 were considered to be differential after ANOVA test. 171 proteins, corresponding to 71 unique gene products have been identified, this set being dominated by cytosolic species and glycolitic enzymes. The ranking of the more abundant spots revealed no differences between samples and indicated fermentative metabolism, and active cell wall biosynthesis, redox homeostasis, biosynthesis of amino acids, coenzymes, nucleotides, and RNA, and protein turnover, apart from cell division and growth. PCA analysis allowed the separation of growth phases (PC1 and 2) and strains at the stationary phase (PC3 and 4), but not at the exponential one. These results are also supported by clustering analysis. As a general tendency, a number of spots newly appeared at the stationary phase in wild type, and to a lesser extent, in the mutant. These up-accumulated spots corresponded to glycolitic enzymes, indicating a more active glucose catabolism, accompanied by an accumulation of methylglyoxal detoxification, and redox-homeostasis enzymes. Also, more extensive proteolysis was observed at the stationary phase with this resulting in an accumulation of low Mr protein species.

  4. Construction and Genetic Analysis of Murine Hepatitis Virus Strain A59 Nsp16 Temperature Sensitive Mutant and the Revertant Virus

    Institute of Scientific and Technical Information of China (English)

    Guo-hui Chang; Bao-jun Luo; Pin Lu; Lei Lin; Xiao-yan Wu; Jing Li; Yi Hu; Qing-yu Zhu

    2011-01-01

    Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely studied model system for Coronavirus replication and pathogenesis. In this study, we created a MHV-A59 temperature sensitive (ts) mutant Wu"-ts18(cd) using the recombinant vaccinia reverse genetics system. Virus replication assay in 17C1-1 cells showed the plaque phenotype and replication characterization of constructed Wu"-ts18(cd) were indistinguishable from the reported ts mutant Wu"-ts 18. Then we cultured the ts mutant Wu"-ts 18(cd) at non-permissive temperature 39.5℃, which "forced" the ts recombinant virus to use second-site mutation to revert from a ts to a non-ts phenotype. Sequence analysis showed most of the revertants had the same single amino acid mutation at Nsp16 position 43. The single amino acid mutation at Nsp16 position 76 or position 130 could also revert the ts mutant Wu"-ts 18 (cd) to non-ts phenotype, an additional independent mutation in Nsp13 position 115 played an important role on plaque size. The results provided us with genetic information on the functional determinants of Nsp16. This allowed us to build up a more reasonable model of CoVs replication-transcription complex.

  5. Genome Sequences of the Oxytetracycline Production Strain Streptomyces rimosus R6-500 and Two Mutants with Chromosomal Rearrangements

    KAUST Repository

    Baranasic, Damir

    2014-07-17

    The genome sequence of Streptomyces rimosus R6-500, an industrially improved strain which produces high titers of the important antibiotic oxytetracycline, is reported, as well as the genome sequences of two derivatives arising due to the genetic instability of the strain.

  6. Production and Accumulation of Xylooligosaccharides with Long Chains by Growing Culture and Xylanase of a Mutant Strain of Bacillus pumilus X-6-19

    Institute of Scientific and Technical Information of China (English)

    Qingzhu Yuan; Tsuyoshi Adachi; Shinji Takenaka; Shuichiro Murakami; Machiko Tanaka; Kenji Aoki

    2008-01-01

    Bacillus pumilus X-6-9 isolated from soil and subsequently identified, produced xylooligosacchatides with long chainsfrom xylan and accumulated them in the culture. By improving the culture conditions and mutating the bacterium, a 3.2-fold increasein the production of the xylooligosaccharides was established, when compared to the original culture conditions of B. pumilus X-6-19.The addition of D-glucose to the culture of the mutant swain U-3 of B. pumilus X-6-9 repressed the synthesis of β-xylosidase, but notxylanase. Thus, it was revealed that strain U-3 was a good organism for the production and accumulation of xylooligosaccharideswith long chains from xylan by a microbial culture. Xylanase produced by strain U-3 was purified to homogeneity and characterized.The hydrolyzates generated by the purified xylanase contained xylobiose, xylotrinse, xylotewaose, and xylopentaose, but not xylose.

  7. Yield and nutritional composition of oyster mushroom strains newly introduced in Bangladesh Produtividade e composição nutricional de linhagens de cogumelo‑ostra recentemente lançadas em Bangladesh

    OpenAIRE

    Mostak Ahmed; Noorlidah Abdullah; Kamal Uddin Ahmed; M. H. M. Borhannuddin Bhuyan

    2013-01-01

    The objective of this work was to evaluate yield and chemical composition of oyster mushroom strains newly introduced in Bangladesh. Strains of Pleurotus high‑king (strain PHK), P. ostreatus (strain PO2), and P. geesteranus (strains PG1 and PG3) were evaluated as to yield components and proximate composition. Pleurotus ostreatus was used as control. Pleurotus high‑king showed fastest growth of primordia, but moderate flush of effective fruiting bodies. Pleurotus geesteranus (PG1) ...

  8. Low dose vaccination with attenuated Francisella tularensis strain SchuS4 mutants protects against tularemia independent of the route of vaccination.

    Directory of Open Access Journals (Sweden)

    Dedeke Rockx-Brouwer

    Full Text Available Tularemia, caused by the gram-negative bacterium Francisella tularensis, is a severe, sometimes fatal disease. Interest in tularemia has increased over the last decade due to its history as a biological weapon. In particular, development of novel vaccines directed at protecting against pneumonic tularemia has been an important goal. Previous work has demonstrated that, when delivered at very high inoculums, administration of live, highly attenuated strains of virulent F. tularensis can protect against tularemia. However, lower vaccinating inoculums did not offer similar immunity. One concern of using live vaccines is that the host may develop mild tularemia in response to infection and use of high inoculums may contribute to this issue. Thus, generation of a live vaccine that can efficiently protect against tularemia when delivered in low numbers, e.g. <100 organisms, may address this concern. Herein we describe the ability of three defined, attenuated mutants of F. tularensis SchuS4, deleted for FTT0369c, FTT1676, or FTT0369c and FTT1676, respectively, to engender protective immunity against tularemia when delivered at concentrations of approximately 50 or fewer bacteria. Attenuated strains for use as vaccines were selected by their inability to efficiently replicate in macrophages in vitro and impaired replication and dissemination in vivo. Although all strains were defective for replication in vitro within macrophages, protective efficacy of each attenuated mutant was correlated with their ability to modestly replicate and disseminate in the host. Finally, we demonstrate the parenteral vaccination with these strains offered superior protection against pneumonic tularemia than intranasal vaccination. Together our data provides proof of principle that low dose attenuated vaccines may be a viable goal in development of novel vaccines directed against tularemia.

  9. Cloning, sequencing, and expression of nitrile hydratase gene of mutant 4D strain of Rhodococcus rhodochrous PA 34 in E. coli.

    Science.gov (United States)

    Pratush, Amit; Seth, Amit; Bhalla, T C

    2012-10-01

    The NHase encoding gene of mutant 4D was isolated by PCR amplification. The NHase gene of mutant 4D was successfully cloned and expressed in Escherichia coli by using Ek/LIC Duet cloning kits (Novagen). For the active expression of the NHase gene, the co-expression of small cobalt transporter gene (P-protein gene) has also been co-expressed with NHase gene E. coli. The nucleotide sequence of this NHase gene revealed high homology with the H-NHase of Rhodococcus rhodochrous J1. The recombinant E. coli cells showed higher NHase activity (5.9 U/mg dcw) as compared to the wild (4.1 U/mg dcw) whereas it is less than the mutant strain (8.4 U/mg dcw). Addition of cobalt ion in Luria-Bertani medium is needed up to a very small concentration (0.4 mM) for NHase activity. The recombinant E. coli exhibited maximum NHase activity at 6 h of incubation and was purified with a yield of 56 % with specific activity of 37.1 U/mg protein.

  10. Low dose vaccination with attenuated Francisella tularensis strain SchuS4 mutants protects against tularemia independent of the route of vaccination.

    Science.gov (United States)

    Rockx-Brouwer, Dedeke; Chong, Audrey; Wehrly, Tara D; Child, Robert; Crane, Deborah D; Celli, Jean; Bosio, Catharine M

    2012-01-01

    Tularemia, caused by the gram-negative bacterium Francisella tularensis, is a severe, sometimes fatal disease. Interest in tularemia has increased over the last decade due to its history as a biological weapon. In particular, development of novel vaccines directed at protecting against pneumonic tularemia has been an important goal. Previous work has demonstrated that, when delivered at very high inoculums, administration of live, highly attenuated strains of virulent F. tularensis can protect against tularemia. However, lower vaccinating inoculums did not offer similar immunity. One concern of using live vaccines is that the host may develop mild tularemia in response to infection and use of high inoculums may contribute to this issue. Thus, generation of a live vaccine that can efficiently protect against tularemia when delivered in low numbers, e.g. tularemia when delivered at concentrations of approximately 50 or fewer bacteria. Attenuated strains for use as vaccines were selected by their inability to efficiently replicate in macrophages in vitro and impaired replication and dissemination in vivo. Although all strains were defective for replication in vitro within macrophages, protective efficacy of each attenuated mutant was correlated with their ability to modestly replicate and disseminate in the host. Finally, we demonstrate the parenteral vaccination with these strains offered superior protection against pneumonic tularemia than intranasal vaccination. Together our data provides proof of principle that low dose attenuated vaccines may be a viable goal in development of novel vaccines directed against tularemia.

  11. Salmonella enterica serovar typhimurium trxA mutants are protective against virulent challenge and induce less inflammation than the live-attenuated vaccine strain SL3261.

    Science.gov (United States)

    Peters, S E; Paterson, G K; Bandularatne, E S D; Northen, H C; Pleasance, S; Willers, C; Wang, J; Foote, A K; Constantino-Casas, F; Scase, T J; Blacklaws, B A; Bryant, C E; Mastroeni, P; Charles, I G; Maskell, D J

    2010-01-01

    In Salmonella enterica serovar Typhimurium, trxA encodes thioredoxin 1, a small, soluble protein with disulfide reductase activity, which catalyzes thiol disulfide redox reactions in a variety of substrate proteins. Thioredoxins are involved as antioxidants in defense against oxidative stresses, such as exposure to hydrogen peroxide and hydroxyl radicals. We have made a defined, complete deletion of trxA in the mouse-virulent S. Typhimurium strain SL1344 (SL1344 trxA), replacing the gene with a kanamycin resistance gene cassette. SL1344 trxA was attenuated for virulence in BALB/c mice by the oral and intravenous routes and when used in immunization experiments provided protection against challenge with the virulent parent strain. SL1344 trxA induced less inflammation in murine spleens and livers than SL3261, the aroA mutant, live attenuated vaccine strain. The reduced splenomegaly observed following infection with SL1344 trxA was partially attributed to a reduction in the number of both CD4(+) and CD8(+) T cells and B lymphocytes in the spleen and reduced infiltration by CD11b(+) cells into the spleen compared with spleens from mice infected with SL3261. This less severe pathological response indicates that a trxA mutation might be used to reduce reactogenicity of live attenuated vaccine strains. We tested this by deleting trxA in SL3261. SL3261 trxA was also less inflammatory than SL3261 but was slightly less effective as a vaccine strain than either the SL3261 parent strain or SL1344 trxA.

  12. Metabolic Engineering of Light and Dark Biochemical Pathways in Wild-Type and Mutant Strains of Synechocystis PCC 6803 for Maximal, 24-Hour Production of Hydrogen Gas

    Energy Technology Data Exchange (ETDEWEB)

    Ely, Roger L.; Chaplen, Frank W.R.

    2014-03-11

    enhanced H2 production profiles using selected culture conditions and inhibitors of specific pathways in WT cells and an NDH-1 mutant; 3. Create Synechocystis PCC 6803 mutant strains with modified hydrogenases exhibiting increased O2 tolerance and greater H2 production; and 4. Integrate enhanced hydrogenase mutants and culture and metabolic factor studies to maximize 24-hour H2 production.

  13. Screening of Saccharomyces Strains Highly Producing Glutathione and Breeding of Its Ethionine-resistant Mutants%高产谷胱甘肽酵母菌株的筛选及其抗乙硫氨酸诱变研究

    Institute of Scientific and Technical Information of China (English)

    冮洁; 单立峰; 吴耘红; 张鹭

    2008-01-01

    [Objective] The aim of this study was to screen Saccharomyces for glutathione over-production. [Method] Ethionine-resistant mutants were obtained through UV mutagenesis and rational screening. [Result] A high GSH-producing strain HSJB1 was isolated from soil, and the biomass for this strain by flask shaking fermentation was 3.87 g/L while the GSH yield was 91.87 mg/L. According to the morphological, physiological and biochemical characteristics of cells, this strain was primarily identified as Saccharomyces cerevisiae. An ethionine-resistant mutant YBS77 was obtained through UV mutagenesis of the original strain HSJB1, and the biomass for this strain by flask shaking fermentation was 7.60 g dry cell weight/L while the GSH yield was 211.96 mg/L. [Conclusion] The biomass of the mutant obtained by breeding is increased by 96.38% than that of the original strain, and the GSH yield of the mutant obtained by breeding is increased by 130.72% than that from the original strain, which indicates that the breeding method is feasible.

  14. JOVIAL/Ada Microprocessor Study.

    Science.gov (United States)

    1982-04-01

    Technical Report Kernighan , B., and Mashey, J., "The UNIX Programing Environment", Computer 14:4, April 1981, pp. 12-24. Kildall, G., "A Unified Approach to...UCSD is a trademark of the Regents of the University of California) UNIX An operating system ( UNIX is a trademark of Bell Laboratories) VAX A...version of UNIX . An eight-user system costs about $30,000. 19 JOVIAL/Ada Microprocessor Study Final Technical Report Another Z8000-based system is the

  15. Construction and characterization of a glycoprotein E deletion mutant of bovine herpesvirus type 1.2 strain isolated in Brazil

    NARCIS (Netherlands)

    Franco, A.C.; Rijsewijk, F.A.M.; Flores, E.F.; Weiblen, R.; Roehe, P.M.

    2002-01-01

    This paper describes the construction and characterization of a Brazilian strain of bovine herpesvirus type 1.2a (BoHV-1.2a) with a deletion of the glycoprotein E (gE) gene. The deletion was introduced by co-transfection of a deletion fragment containing the 5´and 3´gE flanking regions and genomic D

  16. The Use of NF1 and NF2 Mutant Mouse Strains in the Investigation of Gene Function and Disease Development

    Science.gov (United States)

    1998-10-01

    the major symptoms of the disease are schwannomas affecting the eighth cranial nerves, meningiomas and ependymomas. NF2 patients also frequently exhibit...not develop the schwannomas or other CNS tumors that occur in human NF2 (28,29). The generation and initial characterization of these strains was...animal’s back and tongue , respectively. (Note the multinodular nature of the tongue lesion(s)). Only cells associated with the central normal nerve (N

  17. A Comparison of Ada 83 and C++

    Science.gov (United States)

    1991-06-01

    developing large, complex, software systems with long lifetimes. Those interviewed for this study who are familiar with both Ada and C++ believe that Ada is...with those who are familiar with both languages, there was a clear preference for using Ada for large complex systems with long lifetimes. These...University, December 1990 Additions by Nelson H. Weiderman, June 1991. Chile Empresa Nacional de Aeronautica (ENAER), real-time avionics system, Data

  18. [Characteristics of the structural organization of the DIP1 gene in Drosophila melanogaster strains mutant for the flamenco gene].

    Science.gov (United States)

    Nefedova, L N; Romanova, N I; Kim, A I

    2007-01-01

    Molecular cloning of the DIP1 gene located in the 20A4-5 region has been performed from the following strains with the flamenco phenotype: flamSS (SS) and flamMS (MS) characterized by a high transposition rate of retrotransposon gypsy (mdg4), flampy + (P) carrying the insertion of a construction based on the P element into the region of the flamenco gene, and flamenco+. The results of restriction analysis and sequencing cloned DNA fragments has shown that strains flamSS, flamMS, flampy +(P), and flamenco+ considerably differ from one another in the structure of DIP1. Strains flamss and flamMS have no Dral restriction site at position 1765 in the coding region of the gene, specifically, in the domain determining the signal of the nuclear localization of the DIP1 protein. This mutation has been found to consist in a nucleotide substitution in the recognition site of DraI restriction endonuclease, which is transformed from TTTAAA into TTTAAG and, hence, is not recognized by the enzyme. This substitution changes codon AAA into AAG and is translationally insignificant, because both triplets encode the same amino acid, lysine. The Dral gene of strainsflamSS andflamMS has been found to contain a 182-bp insertion denoted IdSS (insertion in DIP1 strain SS); it is located in the second intron of the gene. The IdSS sequence is part of the open reading frame encoding the putative transposase of the mobile genetic element HB1 belonging to the Tcl/mariner family. This insertion is presumed to disturb the conformations of DNA and the chromosome, in particular, by forming loops, which alters the expression of DIPI and, probably, neighboring genes. In strains flamenco+ and flampy + (P), the IdSS insertion within the HB1 sequence is deleted. The deletion encompasses five C-terminal amino acid residues of the conserved domain and the entire C-terminal region of the putative HB1 transposase. The obtained data suggest that DIP1 is involved in the control of gypsy transpositions either

  19. Identificação do potencial amilolítico de linhagens mutantes do fungo filamentoso Aspergillus nidulans Identification of the amylolytic potential of mutant strains of the filamentous fungi Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Izabel Aparecida Soares

    2010-09-01

    Full Text Available As amilases estão entre as mais importantes enzimas industriais, apresentando grande importância biotecnológica, principalmente na indústria alimentícia. Com o avanço no conhecimento das enzimas, a utilização dos fungos como fonte de enzimas vem adquirindo um status de destaque nas mais variadas áreas industriais e comerciais. Diante disso, o presente estudo procurou identificar a presença de atividade amilolítica em quatro linhagens do fungo filamentoso Aspergillus nidulans, selvagem, PAT, biA1methG1 e CLB3, utilizando dois meios distintos de cultura, BDA e Meio Completo a 2% amido, variando os tratamentos com adição ou não de glicose. Foram determinados o diâmetro médio da colônia, o diâmetro médio do halo e o Índice Enzimático. Como resultados, todas as linhagens testadas foram capazes de degradar o amido quando na ausência de glicose, porém o tratamento que obteve estatisticamente melhor crescimento e maior degradação do amido foi o MC sem glicose a 2% amido e a linhagem que se demonstrou potencialmente degradadora de amido foi o mutante CLB3. Conclui-se, portanto, que Aspergillus nidulans pode ser considerado como um produtor de amilases.The amylases are among the most important industrial enzymes showing great biotechnological importance, mainly in the food industry. Due to the advance knowledge in enzyme research, the use of fungi as source of enzymes has acquired a prominent status in most varied industrial and commercial areas. Thus, the present study tried to identify the presence of the amylolytic activity in four stains of filamentous fungi Aspergillus nidulans, selvagem, PAT, biA1methG1 and CLB3 by using two different culture means, PDA and Complete mean with 2% starch, varying the treatments with and without the addition of glucose. The colony average diameter, the halo average diameter, and the enzymatic index were determined. The results show that all strains tested were capable of degrading starch in the

  20. Ada training evaluation and recommendations from the Gamma Ray Observatory Ada Development Team

    Science.gov (United States)

    1985-01-01

    The Ada training experiences of the Gamma Ray Observatory Ada development team are related, and recommendations are made concerning future Ada training for software developers. Training methods are evaluated, deficiencies in the training program are noted, and a recommended approach, including course outline, time allocation, and reference materials, is offered.

  1. Homologous, homeologous, and illegitimate repair of double-strand breaks during transformation of a wild-type strain and a rad52 mutant strain of Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Mezard, C.; Nicolas, A. [Universite Paris-Sud, Orsay (France)

    1994-02-01

    Different modes of in vivo repair of double-strand breaks (DSBs) have been described for various organisms: the recombinational DSB repair (DSBR) mode, the single-strand annealing (SSA) mode, and end-to-end joining. To investigate these modes of DSB repair in Saccharomyces cerevisiae, we have examined the fate of in vitro linearized replicative plasmids during transformation with respect to several parameters. We found that (i) the efficiencies of both intramolecular and intermolecular linear plasmid DSB repair are homology dependent (according to the amount of DNA used during transformation [100 ng or less], recombination between similar but not identical [homeologous] P450s sequences sharing 73% identity is 2- to 18-fold lower than recombination between identical sequences); (ii) the RAD52 gene product is not essential for intramolecular recombination between homologous and homeologous direct repeats (as in the wild-type strain, recombination occurs with respect to the overall alignment of the parental sequences); (iii) in contrast, the RAD52 gene product is required for intermolecular interactions; (iv) similarly, sequencing data revealed examples of intramolecular joining within the few terminal nucleotides of the transforming DNA upon transformation with a linear plasmid with no repeat in the wild-type strain. The recombinant junctions of the rare illegitimate events obtained with S. cerevisiae are very similar to those observed in the repair of DSB in mammalian cells. Together, these and previous results suggest the existence of alternative modes for DSB repair during transformation which differ in their efficiencies and in the structure of their products. We discuss the implications of these results with respect to the existence of alternative pathways and the role of the RAD52 gene product. 67 refs., 4 figs., 5 tabs.

  2. Study on the molecular basis of glucoamylase overproduc-tion of a mutant strain Aspergillus niger T21

    Institute of Scientific and Technical Information of China (English)

    FAN; Xiaochun

    2001-01-01

    [1]Qiao, D., Tang, G., Zhong, L. et al., The overall analysis and comparison of the expression of glucoamylase in the over-production strain A. niger T21 and its original strain A. niger 3.795, Acta Microbiologica Sinica (in Chinese), 1997, 37(5): 349.[2]Zhong, L, Qiao, D, Tang, G. et al., Cloning, sequencing and comparison of the 5′-flanking regions of glaA gene from high and low glucoamylase producing strains of Aspergillus niger, Acta Microbiologica Sinica (in Chinese), 1996, 36: 181.[3]Qiao, D., Zhong, L., Tang, G. et al., Cloning and sequencing of glucoamylase gene from Aspergillus niger 3.795, Chinese J. Biochem. and Mol. Biology (in Chinese), 1998, 14: 254.[4]Zhong, L., Fan, X., Tang, G., Cotransformation of glucoamylase overproducing strain Aspergillus niger T21 with niaD and uidA gene, Mycosystema (in Chinese), 1999, 18: 172.[5]Roberts, I. N., Oliver, R. P., Punt, P. J. et al., Expression of the Escherichia coli b-glucuronidase gene in industrial and phytopathogenic filamentous fungi, Curr. Genet., 1989, 15: 177.[6]Lowry, O. H., Rosebrough, N. J., Farr, A. L. et al., Protein measurement with the folin phenol reagent, J. Biochem., 1951, 193: 268.[7]Zhu, H., Qu, F., Zhu, L., Isolation of genomic DNAs from fungi using benzyl chloride, Acta Mycologica Sinica (in Chi-nese), 1994, 13: 34.[8]Verwoerd, T. C., Dekker, B. M. M., Hoekema, A., A small-scale procedure for the rapid isolation of plant RNAs, Nucleic Acids Research, 1989, 17: 2362.[9]Campbell, E. I., Unkles, S. E., Marco, J. A. et al., Improved transformation efficiency of Aspergillus niger using the ho-mologous niaD gene for nitrate reductase, Curr. Genet., 1989, 16: 53.[10]Fowler, T., Berka, R. M., Ward, M., Regulation of the glaA gene of Aspergillus niger, Curr. Genet., 1990, 18: 537.[11]Verdoes, J. C., Punt, P. J., Stouthamer, A. H. et al., The effect of multiple copies of the upstream region on expression of the Aspergillus niger glucoamylase

  3. Growth, ethanol production, and inulinase activity on various inulin substrates by mutant Kluyveromyces marxianus strains NRRL Y-50798 and NRRL Y-50799.

    Science.gov (United States)

    Galindo-Leva, Luz Ángela; Hughes, Stephen R; López-Núñez, Juan Carlos; Jarodsky, Joshua M; Erickson, Adam; Lindquist, Mitchell R; Cox, Elby J; Bischoff, Kenneth M; Hoecker, Eric C; Liu, Siqing; Qureshi, Nasib; Jones, Marjorie A

    2016-07-01

    Economically important plants contain large amounts of inulin. Disposal of waste resulting from their processing presents environmental issues. Finding microorganisms capable of converting inulin waste to biofuel and valuable co-products at the processing site would have significant economic and environmental impact. We evaluated the ability of two mutant strains of Kluyveromyces marxianus (Km7 and Km8) to utilize inulin for ethanol production. In glucose medium, both strains consumed all glucose and produced 0.40 g ethanol/g glucose at 24 h. In inulin medium, Km7 exhibited maximum colony forming units (CFU)/mL and produced 0.35 g ethanol/g inulin at 24 h, while Km8 showed maximum CFU/mL and produced 0.02 g ethanol/g inulin at 96 h. At 24 h in inulin + glucose medium, Km7 produced 0.40 g ethanol/g (inulin + glucose) and Km8 produced 0.20 g ethanol/g (inulin + glucose) with maximum CFU/mL for Km8 at 72 h, 40 % of that for Km7 at 36 h. Extracellular inulinase activity at 6 h for both Km7 and Km8 was 3.7 International Units (IU)/mL.

  4. Paranoia.Ada: A diagnostic program to evaluate Ada floating-point arithmetic

    Science.gov (United States)

    Hjermstad, Chris

    1986-01-01

    Many essential software functions in the mission critical computer resource application domain depend on floating point arithmetic. Numerically intensive functions associated with the Space Station project, such as emphemeris generation or the implementation of Kalman filters, are likely to employ the floating point facilities of Ada. Paranoia.Ada appears to be a valuabe program to insure that Ada environments and their underlying hardware exhibit the precision and correctness required to satisfy mission computational requirements. As a diagnostic tool, Paranoia.Ada reveals many essential characteristics of an Ada floating point implementation. Equipped with such knowledge, programmers need not tremble before the complex task of floating point computation.

  5. A small evaluation suite for Ada compilers

    Science.gov (United States)

    Wilke, Randy; Roy, Daniel M.

    1986-01-01

    After completing a small Ada pilot project (OCC simulator) for the Multi Satellite Operations Control Center (MSOCC) at Goddard last year, the use of Ada to develop OCCs was recommended. To help MSOCC transition toward Ada, a suite of about 100 evaluation programs was developed which can be used to assess Ada compilers. These programs compare the overall quality of the compilation system, compare the relative efficiencies of the compilers and the environments in which they work, and compare the size and execution speed of generated machine code. Another goal of the benchmark software was to provide MSOCC system developers with rough timing estimates for the purpose of predicting performance of future systems written in Ada.

  6. Yield and nutritional composition of oyster mushroom strains newly introduced in Bangladesh Produtividade e composição nutricional de linhagens de cogumelo‑ostra recentemente lançadas em Bangladesh

    Directory of Open Access Journals (Sweden)

    Mostak Ahmed

    2013-02-01

    Full Text Available The objective of this work was to evaluate yield and chemical composition of oyster mushroom strains newly introduced in Bangladesh. Strains of Pleurotus high‑king (strain PHK, P. ostreatus (strain PO2, and P. geesteranus (strains PG1 and PG3 were evaluated as to yield components and proximate composition. Pleurotus ostreatus was used as control. Pleurotus high‑king showed fastest growth of primordia, but moderate flush of effective fruiting bodies. Pleurotus geesteranus (PG1 showed higher economic yield and biological performance, and better chemical composition, especially in terms of protein and mineral contents. Pleurotus geesteranus (PG1 shows better performance than P. ostreatus (PO2, the most commercially cultivated edible species in Bangladesh, and, therefore, it should be recommended for commercial cultivation.O objetivo deste trabalho foi avaliar a produtividade e a composição química de linhagens de cogumelo‑ostra introduzidas recentemente em Bangladesh. Linhagens de Pleurotus high‑king (linhagem PHK, P. ostreatus (linhagem PO2 e P. geesteranus (linhagens PG1 e PG3 foram avaliadas quanto aos componentes da produção e à composição proximal. Pleurotus ostreatus foi utilizado como controle. Pleurotus high‑king apresentou rápido crescimento de primórdios, mas fluxo moderado de corpos de frutificação efetivos. Pleurotus geesteranus (PG1 apresentou maior produtividade econômica e desempenho biológico, além de melhor composição química, especialmente em termos de conteúdos de proteína e minerais. Pleurotus geesteranus (PG1 apresenta melhor desempenho que P. ostreatus (linhagem PO2, a espécie comestível mais cultivada comercialmente em Bangladesh, e, portanto, deve ser recomendado para plantio comercial.

  7. Development of an Ada programming support environment database SEAD (Software Engineering and Ada Database) administration manual

    Science.gov (United States)

    Liaw, Morris; Evesson, Donna

    1988-01-01

    Software Engineering and Ada Database (SEAD) was developed to provide an information resource to NASA and NASA contractors with respect to Ada-based resources and activities which are available or underway either in NASA or elsewhere in the worldwide Ada community. The sharing of such information will reduce duplication of effort while improving quality in the development of future software systems. SEAD data is organized into five major areas: information regarding education and training resources which are relevant to the life cycle of Ada-based software engineering projects such as those in the Space Station program; research publications relevant to NASA projects such as the Space Station Program and conferences relating to Ada technology; the latest progress reports on Ada projects completed or in progress both within NASA and throughout the free world; Ada compilers and other commercial products that support Ada software development; and reusable Ada components generated both within NASA and from elsewhere in the free world. This classified listing of reusable components shall include descriptions of tools, libraries, and other components of interest to NASA. Sources for the data include technical newletters and periodicals, conference proceedings, the Ada Information Clearinghouse, product vendors, and project sponsors and contractors.

  8. Nif- Hup- mutants of Rhizobium japonicum.

    OpenAIRE

    Moshiri, F; Stults, L; Novak, P.; Maier, R J

    1983-01-01

    Two H2 uptake-negative (Hup-) Rhizobium japonicum mutants were obtained that also lacked symbiotic N2 fixation (acetylene reduction) activity. One of the mutants formed green nodules and was deficient in heme. Hydrogen oxidation activity in this mutant could be restored by the addition of heme plus ATP to crude extracts. Bacteroid extracts from the other mutant strain lacked hydrogenase activity and activity for both of the nitrogenase component proteins. Hup+ revertants of the mutant strains...

  9. Experiences with Ada in an embedded system

    Science.gov (United States)

    Labaugh, Robert J.

    1988-01-01

    Recent experiences with using Ada in a real time environment are described. The application was the control system for an experimental robotic arm. The objectives of the effort were to experiment with developing embedded applications in Ada, evaluating the suitability of the language for the application, and determining the performance of the system. Additional objectives were to develop a control system based on the NASA/NBS Standard Reference Model for Telerobot Control System Architecture (NASREM) in Ada, and to experiment with the control laws and how to incorporate them into the NASREM architecture.

  10. Hydrogen production by hup(-) mutant and wild-type strains of Rhodobacter capsulatus from dark fermentation effluent of sugar beet thick juice in batch and continuous photobioreactors.

    Science.gov (United States)

    Uyar, Basar; Gürgan, Muazzez; Özgür, Ebru; Gündüz, Ufuk; Yücel, Meral; Eroglu, Inci

    2015-10-01

    Photofermentative production of hydrogen is a promising and sustainable process; however, it should be coupled to dark fermentation to become cost effective. In order to integrate dark fermentation and photofermentation, the suitability of dark fermenter effluents for the photofermentative hydrogen production must be demonstrated. In this study, thermophilic dark fermenter effluent (DFE) of sugar beet thick juice was used as a substrate in photofermentation process to compare wild-type and uptake hydrogenase-deficient (hup (-)) mutant strains of Rhodobacter capsulatus by means of hydrogen production and biomass growth. The tests were conducted in small-scale (50 mL) batch and large-scale (4 L) continuous photobioreactors in indoor conditions under continuous illumination. In small scale batch conditions, maximum cell concentrations were 0.92 gdcw/L c and 1.50 gdcw/L c, hydrogen yields were 34 % and 31 %, hydrogen productivities were 0.49 mmol/(L c·h) and 0.26 mmol/(Lc·h), for hup (-) and wild-type cells, respectively. In large-scale continuous conditions, maximum cell concentrations were 1.44 gdcw/L c and 1.87 gdcw/L c, hydrogen yields were 48 and 46 %, and hydrogen productivities were 1.01 mmol/(L c·h) and 1.05 mmol/(L c·h), for hup (-) and wild-type cells, respectively. Our results showed that Rhodobacter capsulatus hup (-) cells reached to a lower maximum cell concentration but their hydrogen yield and productivity were in the same range or superior compared to the wild-type cells in both batch and continuous operating modes. The maximum biomass concentration, yield and productivity of hydrogen were higher in continuous mode compared to the batch mode with both bacterial strains.

  11. Computation of interactive effects and optimization of process parameters for alkaline lipase production by mutant strain of Pseudomonas aeruginosa using response surface methodology

    Directory of Open Access Journals (Sweden)

    Deepali Bisht

    2013-01-01

    Full Text Available Alkaline lipase production by mutant strain of Pseudomonas aeruginosa MTCC 10,055 was optimized in shake flask batch fermentation using response surface methodology. An empirical model was developed through Box-Behnken experimental design to describe the relationship among tested variables (pH, temperature, castor oil, starch and triton-X-100. The second-order quadratic model determined the optimum conditions as castor oil, 1.77 mL.L-1; starch, 15.0 g.L-1; triton-X-100, 0.93 mL.L-1; incubation temperature, 34.12 ºC and pH 8.1 resulting into maximum alkaline lipase production (3142.57 U.mL-1. The quadratic model was in satisfactory adjustment with the experimental data as evidenced by a high coefficient of determination (R² value (0.9987. The RSM facilitated the analysis and interpretation of experimental data to ascertain the optimum conditions of the variables for the process and recognized the contribution of individual variables to assess the response under optimal conditions. Hence Box-Behnken approach could fruitfully be applied for process optimization.

  12. High-yield production of aryl alcohol oxidase under limited growth conditions in small-scale systems using a mutant Aspergillus nidulans strain.

    Science.gov (United States)

    Pardo-Planas, Oscar; Prade, Rolf A; Wilkins, Mark R

    2017-02-01

    Aryl alcohol oxidase (MtGloA) is an enzyme that belongs to the ligninolytic consortium and can play an important role in the bioenergy industry. This study investigated production of an MtGloA client enzyme by a mutant strain of Aspergillus nidulans unable to synthesize its own pyridoxine. Pyridoxine limitation can be used to control cell growth, diverting substrate to protein production. In agitated culture, enzyme production was similar when using media with 1 mg/L and without pyridoxine (26.64 ± 6.14 U/mg mycelia and 26.14 ± 8.39 U/mg mycelia using media with and without pyridoxine, respectively). However, the treatment lacking pyridoxine had to be supplemented with pyridoxine after 156 h of fermentation to sustain continued enzyme production. Use of extremely diluted pyridoxine levels allowed reduced fungal growth while maintaining steady enzyme production. Concentrations of 9 and 13.5 µg/L pyridoxine allowed MtGloA production with a growth rate of only 5% of that observed when using the standard 1 mg/L pyridoxine media.

  13. Purification and Characterization of a New Heme-Binding Protein (HBP59) from the Mutant Strain DJ35 of Azotobacter vinelandii

    Institute of Scientific and Technical Information of China (English)

    Shao-Min Bian; Huang-Ping Wang; Hui-Na Zhou; Ying Zhao; Jian-Feng Zhao; Ju-Fu Huang

    2007-01-01

    A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandli Lipmann. After analysis by matrix-assisted laser desorptlon ionization time-offlight mass spectrometry, the protein was identified as the product of a predicted gene. Thus, the protein was tentatively called HBP59. Its absorption spectra (ABS) in the reduced state exhibited three peaks at 421,517, and 556nm and the maximal peak was shifted from 421 to 413 nm after exposure of HBP59 to air. The Soret circular dichroism (CD) spectrum of HBP59 in the reduced state displayed four positive peaks at 364, 382, 406, and 418 nm and two negative peaks at 398 and 433 nm; the Δε (CD extinction coefficient) values of these peaks were found to be 0.92, 0.58, 0.87, 0.72, -0.65 and -1.12 L/mol per cm, respectively. Titration with heme showed that the protein has 0.1 heme molecules/protein molecule. After HBP59 had fully interacted with heme, its maximal ABS value and Soret CD intensity were increased by approximately 10-fold compared with values before interaction. Therefore, it seems that one molecule of HBP59 can be interacted with only one heme. These results indicate that HBP59 contains heme with iow spin and may be involved in heme utilization or adhesion.

  14. Ada Compiler Validation Summary Report: Western Digital STC-Ada Compiler, Version C1. Om V-004.

    Science.gov (United States)

    1983-07-28

    C27001A.ADA P SC 2 10 C27002A-B.ADA P SC x 15 829001A.ADA PS SC a 126 EC 262 A29002A-B.ADA P SCz 74 A29002B-.B.ADA P SC a 69 A29002C-B. ADA P SC z 68...s 15 D32202Bm-B.ADA P SC a 21 SC 2 9 B32202C-D.ADA P SC.x 28 EC x:12 C32203A-B.ADA P SC a 15 *A32203i68.ADA P SC a 22 A32203C-B.ADA P SCx 18 A32203D...B.ADA P SC a 16 B33001A.ADA P SC a 27 SC a 10 833002A.ADA PS SC a 8 EC x 5 533003A.ADA P SCx 14 EC a 4 B33003B-AS.ADA P SC a 22 EC a 9 533003C-AB.ADA

  15. ADA and C++ Business Case Analysis

    Science.gov (United States)

    1991-07-01

    compilation times, execution times, and various measures of space requirements. The as- sessments in the comparative analysis were refined using a Delphi ...weighted scoring and tables of results, to the group as a whole. Then a Delphi technique similar to the FAA methodology was used to refine the evaluations...promoter of reusability, or injector of added quality, then our3collective judgements may be biased too much towards Ada. Of course the next Ada 9X team

  16. Ada (Trade Name) Bibliography. Volume 1.

    Science.gov (United States)

    1983-05-01

    FISHER, DR. DAVID A.; WETHERALL, PHILIP R. DOCUMENT NUMBER: 3435 DOCUMENT DATE: 01/78 TYPE: TECHNICAL REPORT This report discusses the considerations...SPONOR ADA JT. PROG. OFF., ARLINGTON, VA 22209 - DATABASE PORTABILITY ISSUES IN THE KAPSE KOTLER , REED S. DOCUMENT NUMBER: 3590 TYPE: PAPER KERNEL ADA...N,., BABEL, PHILIPS ., U.S.A.F. ASD,WRIGHT-PATTERSON AFB, OH 5653 -03 JOINT-SERVICE ACQUISITION MANAGEMENT INITIATIVES € BABICH, WAYNEA., SOFTECHINC

  17. A W-Grammar Description for ADA.

    Science.gov (United States)

    1986-12-01

    Language Reference Manual. In MT opinion, the W- gramars fall short of this goal since they are less readable than BNF for determining Ada’s syntax, and...37 Summary . . . . . . . . . . . . . . .... . 39 V. Conclusion .. . . . . . . . . . .. . . .* . . . . 40 Ada Constructs Not Covered in W- gramar B...library unit. The problem with the Language Reference Manual description is not that BNF is too antiquated for language definition, but that English

  18. An Embedded Rule-Based Diagnostic Expert System in Ada

    Science.gov (United States)

    Jones, Robert E.; Liberman, Eugene M.

    1992-01-01

    Ada is becoming an increasingly popular programming language for large Government-funded software projects. Ada with it portability, transportability, and maintainability lends itself well to today's complex programming environment. In addition, expert systems have also assumed a growing role in providing human-like reasoning capability expertise for computer systems. The integration is discussed of expert system technology with Ada programming language, especially a rule-based expert system using an ART-Ada (Automated Reasoning Tool for Ada) system shell. NASA Lewis was chosen as a beta test site for ART-Ada. The test was conducted by implementing the existing Autonomous Power EXpert System (APEX), a Lisp-based power expert system, in ART-Ada. Three components, the rule-based expert systems, a graphics user interface, and communications software make up SMART-Ada (Systems fault Management with ART-Ada). The rules were written in the ART-Ada development environment and converted to Ada source code. The graphics interface was developed with the Transportable Application Environment (TAE) Plus, which generates Ada source code to control graphics images. SMART-Ada communicates with a remote host to obtain either simulated or real data. The Ada source code generated with ART-Ada, TAE Plus, and communications code was incorporated into an Ada expert system that reads the data from a power distribution test bed, applies the rule to determine a fault, if one exists, and graphically displays it on the screen. The main objective, to conduct a beta test on the ART-Ada rule-based expert system shell, was achieved. The system is operational. New Ada tools will assist in future successful projects. ART-Ada is one such tool and is a viable alternative to the straight Ada code when an application requires a rule-based or knowledge-based approach.

  19. Transformation of ADA programs into silicon

    Science.gov (United States)

    Organick, E. I.; Lindstrom, G.; Smith, D. K.; Subrahmany; Carter, T.

    1982-03-01

    This report outlines the beginning steps taken in an integrated research effort toward the development of a methodology, and supporting systems, for transforming Ada programs, or program units, (directly) into corresponding VLSI systems. The time seems right to expect good results. The need is evident; special purpose systems should be realistic alternatives where simplicity, speed, reliability, and security ae dominant factors. Success in this research can lead to attractive options for embedded system applications. Ada programs can be regarded as ensembles of machines, one per program unit (module), which in turn may be mapped directly into corresponding VLSI structures on one or more chips with interconnecting (packet switched or other) communication nets. The research reported here is part of a five-year plan, the first year of which focuses on 'proving' the concepts through a realistic demonstration of methodology for a specific example Ada program (a silicon representation of part or all of the DoD Standard Internet Protocol, IP, initially expressed in Ada). Implicit in these objectives is the development of a set of hardware structuring paradigms (rewrite rules) whose application can ensure that transformation steps between levels of abstraction in the design process are well structured in order to preserve the integrity and, where possible, the clarity of the original Ada specification. Some paradigms, but of course not all, lead to highly efficient implementations.

  20. A database management capability for Ada

    Science.gov (United States)

    Chan, Arvola; Danberg, SY; Fox, Stephen; Landers, Terry; Nori, Anil; Smith, John M.

    1986-01-01

    The data requirements of mission critical defense systems have been increasing dramatically. Command and control, intelligence, logistics, and even weapons systems are being required to integrate, process, and share ever increasing volumes of information. To meet this need, systems are now being specified that incorporate data base management subsystems for handling storage and retrieval of information. It is expected that a large number of the next generation of mission critical systems will contain embedded data base management systems. Since the use of Ada has been mandated for most of these systems, it is important to address the issues of providing data base management capabilities that can be closely coupled with Ada. A comprehensive distributed data base management project has been investigated. The key deliverables of this project are three closely related prototype systems implemented in Ada. These three systems are discussed.

  1. Program Office Guide to Ada. Edition 1

    Science.gov (United States)

    1986-09-17

    Storage Allocation 3-11 3.2.2.4 Rendezvous 3-11 3.3 ALTERNATIVES IN CUSTOM RUN-TIME SUPPORT 3-12 ENVIRONMENTS ( RSE ) 3.3.1 Unique RSE for Each...Tailoring Run-time Support Environments ( RSE ) The minimal Ada compilation system must include a Run- time Support Environment ( RSE ). The code generated by...a typical Ada compiler calls on the RSE to obtain the run-time system services necessary for execution. The RSE consists of primitive and system

  2. Object-Oriented Database Access from Ada

    Science.gov (United States)

    1993-03-01

    programs’ sizes in Ada are larger than C’s. Strong type checking and the interface programs added overhead can probably explain this. 4.3 Problema ...Verdix Corporation. Verdix Ada Development System, 1991. BIB-2 Vita Lt Col Li Chou (ROCAF, Taiwan ) was born on 28 October 1957 in I-Lan, Taiwan ...Republic of China . He graduated from high school in I-Lan in June, 1975. He then entered the National Defense Medical Center from which he graduated in 1980

  3. Ada Formal Methods in the STARS Environment

    Science.gov (United States)

    1992-06-03

    Ariel Semantics for nanoAVA ....... ........................ 56 5.3.1 Caliban Types ....................................... 56 5.3.2 Caliban ...Expressions ........ ........................... 57 5.3.3 Caliban Definitions ........ ............................ 58 5.3.4 Clio’s Metalanguage...59 5.3.5 A Summary of Ada-Ariel Semantics ........................ 60 5.3.6 A Caliban Encoding of an Ariel Semantics for

  4. AdaNET prototype library administration manual

    Science.gov (United States)

    Hanley, Lionel

    1989-01-01

    The functions of the AdaNET Prototype Library of Reusable Software Parts is described. Adopted from the Navy Research Laboratory's Reusability Guidebook (V.5.0), this is a working document, customized for use the the AdaNET Project. Within this document, the term part is used to denote the smallest unit controlled by a library and retrievable from it. A part may have several constituents, which may not be individually tracked. Presented are the types of parts which may be stored in the library and the relationships among those parts; a concept of trust indicators which provide measures of confidence that a user of a previously developed part may reasonably apply to a part for a new application; search and retrieval, configuration management, and communications among those who interact with the AdaNET Prototype Library; and the AdaNET Prototype, described from the perspective of its three major users: the part reuser and retriever, the part submitter, and the librarian and/or administrator.

  5. Alma Flor Ada: Writer, Translator, Storyteller.

    Science.gov (United States)

    Brodie, Carolyn S.

    2003-01-01

    Discusses the work of children's author Alma Flor Ada, a Cuban native who has won awards honoring Latino writers and illustrators. Includes part of an interview that explores her background, describes activity ideas, and presents a bibliography of works written by her (several title published in both English and Spanish) as well as sources of…

  6. LAS DOS TRÍADAS DEBEJARANO

    Directory of Open Access Journals (Sweden)

    Jorge Iván González

    Full Text Available El artículo diseute "dos tríadas" que propone Bejarano para calificar a la teoría económica actual. La primera tríada tiene que ver con el realismo, la pertinencia y la relevancia de la teoría. Y la segunda tríada con sus dimensiones política, institucional y moral. El artículo centra la atención en esta segunda tríada, argumentando que la teoría no es apolítica, ainstitucional y amoral como afirma Bejarano. El examen crítico de la posición de Bejarano se sustenta en algunas de las tesis de: Walras, Marshall, Hicks, vickrey, Samuelson y Arrow.This article discusses the "two triads" that Bejarano has proposed in order to describe present economic theory. The first triad refers to the realism, pertinence and relevance of the theory. The second triad to its political, institutional and moral dimension. The article centers its attention on this second triad, arguing that the theory is not apolitical, uninstitutional and amoral as Bejarano states. The critical examination of Bejarano's proposition is supported on thesis of Walras, Marshall, Hicks, Vickrey, Samuelson and Arrow.

  7. ADA Integrated Environment I. System Specification.

    Science.gov (United States)

    1981-12-01

    returned. UNCLASSIFIED SECt AITY CLASSIFICATION O r THiS PAGE ("On’ Dese ,9nA.,d)l ,_ REPORT DOCUMENTATION PAGE BEFO scOL’No RM 1. RqEPl~ORT, NUM1191N 2...keyboard interactive, and high-band-width graphics terminals. The standard Ada character set is specified; 5. establish and maintain (that is, enter

  8. 49 CFR 37.125 - ADA paratransit eligibility: Process.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false ADA paratransit eligibility: Process. 37.125... INDIVIDUALS WITH DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.125 ADA paratransit eligibility: Process. Each public entity required to provide complementary paratransit service...

  9. 49 CFR 37.123 - ADA paratransit eligibility: Standards.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false ADA paratransit eligibility: Standards. 37.123... INDIVIDUALS WITH DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.123 ADA paratransit eligibility: Standards. (a) Public entities required by § 37.121 of this subpart to...

  10. Knowledge, programming, and programming cultures: LISP, C, and Ada

    Science.gov (United States)

    Rochowiak, Daniel

    1990-01-01

    The results of research 'Ada as an implementation language for knowledge based systems' are presented. The purpose of the research was to compare Ada to other programming languages. The report focuses on the programming languages Ada, C, and Lisp, the programming cultures that surround them, and the programming paradigms they support.

  11. A Salmonella Enteritidis hilAssrAfliG deletion mutant is a safe live vaccine strain that confers protection against colonization by Salmonella Enteritidis in broilers.

    Science.gov (United States)

    De Cort, W; Geeraerts, S; Balan, V; Elroy, M; Haesebrouck, F; Ducatelle, R; Van Immerseel, F

    2013-10-17

    Consumption of contaminated poultry meat is an important cause of Salmonella infections in humans. Therefore, there is a need for control methods that protect broilers from day-of-hatch until slaughter age against infection with Salmonella. Colonization-inhibition, a concept in which a live Salmonella strain is orally administered to day-old chickens and protects against subsequent challenge, can potentially be used as control method. In this study, the safety and efficacy of a Salmonella Enteritidis ΔhilAssrAfliG strain as a colonization-inhibition strain for protection of broilers against Salmonella Enteritidis was evaluated. After administration of the Salmonella Enteritidis ΔhilAssrAfliG strain to day-old chickens, this strain could not be isolated from the gut, internal organs or faeces after 21 days of age. In addition, administration of this strain to one-day-old broiler chickens decreased faecal shedding and caecal and internal organ colonization of a Salmonella Enteritidis challenge strain administered one day later using a seeder bird model. To our knowledge, this is the first report of an attenuated Salmonella strain for which both the safety and efficacy has been shown in long-term experiments (until slaughter age) in broiler strain can potentially be used as a live colonization-inhibition strain for controlling Salmonella Enteritidis infections in broilers.

  12. Observation on biological characters of Streptococcus mutans luxS gene knockout mutant strain%变异链球菌luxS基因缺陷突变株生物学性状的初步观察

    Institute of Scientific and Technical Information of China (English)

    黄正蔚; 刘正; 马瑞; 唐子圣; 朱彩莲

    2008-01-01

    目的 为研究口腔主要致龋菌变异链球菌的种属间密度感应(quorum sensing)相关基因luxS对口腔生态的影响,构建此菌的luxS基因缺失突变株.方法 采用同源重组的方法,利用红霉素耐药基因erm置换变异链球菌基因组中的luxS基因,并在含抗性标记的选择性培养基上筛选出阳性克隆.初步研究该基因的缺失突变对变异链球菌在生长与生物被膜成熟分化中的作用.结果经PCR鉴定,luxS基因的置换突变位置正确,并能在体外稳定传代,突变株与野生株相比在达静止期后总菌数量上有明显差别,但在生物被膜的形成与分化上并未发现显著差异.结论 通过此研究建立了可稳定传代的变异链球菌luxS基因的缺失突变株,生长表型和生物被膜的形成与野生株无显著差异,为进一步研究此基因功能与调控机制提供了技术平台.%Objective To investigate the construction of Streptococcus mutans luxS gene knockout mutant which can act as the technical platform for following researches on luxS quorum sensing function in oral ecosystem.Methods Erythromycin resistance gene was inserted between two 1 kb fragments containing regions of DNA immediately upstream and downstream of the luxS translational start and stop codons.The resuhing construct was linearized and electro-transformed into Streptococcus mutans cells.After allelic exchange,the luxS gene knockout mutant strains were selected on 10μg/ml erythromycin plates,and compared the growth and biofilms formation of luxS knockout mutant with wild type strains.Results The luxSknockout mutant was confirmed by PCR,and it was also confirmed that this gene mutant could be stably passed through in vitro.The growth mode of luxS knockout mutant showed obvious difierences against that of wild type at stationary phase,the knockout mutant gained more bacteria cells growth.Conclusion Streptococcus mutans luxS gene has been successfully disrupted with allelic

  13. Identification of concomitant infection with Chlamydia trachomatis IncA-negative mutant and wild-type strains by genomic, transcriptional, and biological characterizations.

    Science.gov (United States)

    Suchland, Robert J; Jeffrey, Brendan M; Xia, Minsheng; Bhatia, Ajay; Chu, Hencelyn G; Rockey, Daniel D; Stamm, Walter E

    2008-12-01

    Clinical isolates of Chlamydia trachomatis that lack IncA on their inclusion membrane form nonfusogenic inclusions and have been associated with milder, subclinical infections in patients. The molecular events associated with the generation of IncA-negative strains and their roles in chlamydial sexually transmitted infections are not clear. We explored the biology of the IncA-negative strains by analyzing their genomic structure, transcription, and growth characteristics in vitro and in vivo in comparison with IncA-positive C. trachomatis strains. Three clinical samples were identified that contained a mixture of IncA-positive and -negative same-serovar C. trachomatis populations, and two more such pairs were found in serial isolates from persistently infected individuals. Genomic sequence analysis of individual strains from each of two serovar-matched pairs showed that these pairs were very similar genetically. In contrast, the genome sequence of an unmatched IncA-negative strain contained over 5,000 nucleotide polymorphisms relative to the genome sequence of a serovar-matched but otherwise unlinked strain. Transcriptional analysis, in vitro culture kinetics, and animal modeling demonstrated that IncA-negative strains isolated in the presence of a serovar-matched wild-type strain are phenotypically more similar to the wild-type strain than are IncA-negative strains isolated in the absence of a serovar-matched wild-type strain. These studies support a model suggesting that a change from an IncA-positive strain to the previously described IncA-negative phenotype may involve multiple steps, the first of which involves a translational inactivation of incA, associated with subsequent unidentified steps that lead to the observed decrease in transcript level, differences in growth rate, and differences in mouse infectivity.

  14. A dnaN plasmid shuffle strain for rapid in vivo analysis of mutant Escherichia coli β clamps provides insight into the role of clamp in umuDC-mediated cold sensitivity.

    Directory of Open Access Journals (Sweden)

    Vignesh M P Babu

    Full Text Available The E. coli umuDC gene products participate in two temporally distinct roles: UmuD2C acts in a DNA damage checkpoint control, while UmuD'2C, also known as DNA polymerase V (Pol V, catalyzes replication past DNA lesions via a process termed translesion DNA synthesis. These different roles of the umuDC gene products are managed in part by the dnaN-encoded β sliding clamp protein. Co-overexpression of the β clamp and Pol V severely blocked E. coli growth at 30°C. We previously used a genetic assay that was independent of the ability of β clamp to support E. coli viability to isolate 8 mutant clamp proteins (βQ61K, βS107L, βD150N, βG157S, βV170M, βE202K, βM204K and βP363S that failed to block growth at 30°C when co-overexpressed with Pol V. It was unknown whether these mutant clamps were capable of supporting E. coli viability and normal umuDC functions in vivo. The goals of this study were to answer these questions. To this end, we developed a novel dnaN plasmid shuffle assay. Using this assay, βD150N and βP363S were unable to support E. coli viability. The remaining 6 mutant clamps, each of which supported viability, were indistinguishable from β+ with respect to umuDC functions in vivo. In light of these findings, we analyzed phenotypes of strains overexpressing either β clamp or Pol V alone. The strain overexpressing β+, but not those expressing mutant β clamps, displayed slowed growth irrespective of the incubation temperature. Moreover, growth of the Pol V-expressing strain was modestly slowed at 30°, but not 42°C. Taken together, these results suggest the mutant clamps were identified due to their inability to slow growth rather than an inability to interact with Pol V. They further suggest that cold sensitivity is due, at least in part, to the combination of their individual effects on growth at 30°C.

  15. A dnaN plasmid shuffle strain for rapid in vivo analysis of mutant Escherichia coli β clamps provides insight into the role of clamp in umuDC-mediated cold sensitivity.

    Science.gov (United States)

    Babu, Vignesh M P; Sutton, Mark D

    2014-01-01

    The E. coli umuDC gene products participate in two temporally distinct roles: UmuD2C acts in a DNA damage checkpoint control, while UmuD'2C, also known as DNA polymerase V (Pol V), catalyzes replication past DNA lesions via a process termed translesion DNA synthesis. These different roles of the umuDC gene products are managed in part by the dnaN-encoded β sliding clamp protein. Co-overexpression of the β clamp and Pol V severely blocked E. coli growth at 30°C. We previously used a genetic assay that was independent of the ability of β clamp to support E. coli viability to isolate 8 mutant clamp proteins (βQ61K, βS107L, βD150N, βG157S, βV170M, βE202K, βM204K and βP363S) that failed to block growth at 30°C when co-overexpressed with Pol V. It was unknown whether these mutant clamps were capable of supporting E. coli viability and normal umuDC functions in vivo. The goals of this study were to answer these questions. To this end, we developed a novel dnaN plasmid shuffle assay. Using this assay, βD150N and βP363S were unable to support E. coli viability. The remaining 6 mutant clamps, each of which supported viability, were indistinguishable from β+ with respect to umuDC functions in vivo. In light of these findings, we analyzed phenotypes of strains overexpressing either β clamp or Pol V alone. The strain overexpressing β+, but not those expressing mutant β clamps, displayed slowed growth irrespective of the incubation temperature. Moreover, growth of the Pol V-expressing strain was modestly slowed at 30°, but not 42°C. Taken together, these results suggest the mutant clamps were identified due to their inability to slow growth rather than an inability to interact with Pol V. They further suggest that cold sensitivity is due, at least in part, to the combination of their individual effects on growth at 30°C.

  16. Attenuated Actinobacillus pleuropneumoniae double-deletion mutant S-8∆clpP/apxIIC confers protection against homologous or heterologous strain challenge.

    Science.gov (United States)

    Xie, Fang; Li, Gang; Zhou, Long; Zhang, Yanhe; Cui, Ning; Liu, Siguo; Wang, Chunlai

    2017-01-06

    Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, which leads to large economic losses to the swine industry worldwide. In this study, S-8△clpP△apxIIC, a double-deletion mutant of A. pleuropneumoniae was constructed, and its safety and protective efficacy were evaluated in pigs. The S-8△clpP△apxIIC mutant exhibited attenuated virulence in a murine (BALB/c) model, and caused no detrimental effects on pigs even at a dose of up to 1.0 × 10(9) CFU. Furthermore, the S-8△clpP△apxIIC mutant was able to induce a strong immune response in pigs, which included high levels of IgG1 and IgG2, stimulated gamma interferon (IFN-γ), interleukin 12 (IL-12), and interleukin 4 (IL-4) production, and conferred effective protection against the lethal challenge with A. pleuropneumoniae serovars 7 or 5a. The pigs in the S-8△clpP△apxIIC immunized groups have no lesions and reduced bacterial loads in the lung tissue after challenge. The data obtained in this study suggest that the S-8△clpP△apxIIC mutant can serve as a highly immunogenic and potential live attenuated vaccine candidate against A. pleuropneumoniae infection.

  17. The isolation and characterization of a mutant strain of Saccharomyces cerevisiae that requires a long chain base for growth and for synthesis of phosphosphingolipids.

    Science.gov (United States)

    Wells, G B; Lester, R L

    1983-09-10

    A mutant of Saccharomyces cerevisiae has been obtained that shows an absolute growth requirement for long chain bases found in sphingolipids. In the absence of a long chain base, the cells are unable to synthesize the phosphoinositol-containing sphingolipids characteristic of yeast. These results suggest that one or more of the yeast sphingolipids plays a vital biological role.

  18. 突变株CTM2降解苯酚和4-氯酚的生物降解特性%Biodegradation of Phenol and 4-Chlorophenol by the Mutant Strain CTM 2

    Institute of Scientific and Technical Information of China (English)

    姜岩; 任南琪; 蔡徇; 吴迪; 乔丽艳; 林森

    2008-01-01

    The biodegradations of phenol and 4-chlorophenol(4-cp)were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on wild-type Candida tropicalis.The results showed that the capacity of the CTM 2 to biodegrade 4-cp was increased up to 400 mg.L-1 within 59.5 h.In the dual.substrate biodegradation,both 2 to degrade phenol.In addition,the kinetic behaviors were described using the kinetic model proposed in this lab.

  19. The effects of modeled microgravity on growth kinetics, antibiotic susceptibility, cold growth, and the virulence potential of a Yersinia pestis ymoA-deficient mutant and its isogenic parental strain.

    Science.gov (United States)

    Lawal, Abidat; Kirtley, Michelle L; van Lier, Christina J; Erova, Tatiana E; Kozlova, Elena V; Sha, Jian; Chopra, Ashok K; Rosenzweig, Jason A

    2013-09-01

    Previously, we reported that there was no enhancement in the virulence potential (as measured by cell culture infections) of the bacterial pathogen Yersinia pestis (YP) following modeled microgravity/clinorotation growth. We have now further characterized the effects of clinorotation (CR) on YP growth kinetics, antibiotic sensitivity, cold growth, and YP's virulence potential in a murine model of infection. Surprisingly, none of the aforementioned phenotypes were altered. To better understand why CR did not enhance YP's virulence potential as it did for other bacterial pathogens, a YP ΔymoA isogenic mutant in the KIM/D27 background strain that is unable to produce the histone-like YmoA protein and influences DNA topography was used in both cell culture and murine models of infection. YmoA represses type three secretion system (T3SS) virulence gene expression in the yersiniae. Similar to our CR-grown parental YP strain data, the CR-grown ΔymoA mutant induced reduced HeLa cell cytotoxicity with concomitantly decreased Yersinia outer protein E (YopE) and low calcium response V (LcrV) antigen production and secretion. Important, however, were our findings that, although no significant differences were observed in survival of mice infected intraperitoneally with either normal gravity (NG)- or CR-grown parental YP, the ΔymoA mutant induced significantly more mortality in infected mice than did the parental strain following CR growth. Taken together, our data demonstrate that CR did enhance the virulence potential of the YP ΔymoA mutant in a murine infection model (relative to the CR-grown parental strain), despite inducing less HeLa cell rounding in our cell culture infection assay due to reduced T3SS activity. Therefore, CR, which induces a unique type of bacterial stress, might be enhancing YP's virulence potential in vivo through a T3SS-independent mechanism when the histone-like YmoA protein is absent.

  20. Ada (Trade Name) Bibliography. Volume 2.

    Science.gov (United States)

    1984-03-01

    describes the characteristics that " such methologies should possess, Emphasis is given to the process by which software is developed for Ada applications...1. PP. 30-35. 01/82 This article is a proposal for an experiment to relate software metrics to software project observables , in particular to the...that arise in developing embedded software systems. The case studies are of two kinds: pedagogical and observational . The pedagogical case studies

  1. Ada for Embedded Systems: Issues and Questions.

    Science.gov (United States)

    1987-12-01

    appropriate order based on the task dependency hierarchy, which the ART maintains and adds to when tasks are created [ Reino 86]. The master-slave, parent...termination are needed [ Reino 86]. Tasks provide a considerable overhead in the runtime system because the status must be maintained for context...Practitioners Approach. McGraw-Hill International, 1982. [ Reino 86] Kurki-Suonio, R. An Operational Model for Ada Tasking. Technical Report 1/1986, Tampere

  2. Ada (Trade Name) Bibliography. Volume 3.

    Science.gov (United States)

    1986-02-01

    MARIA : FREEMAN. PETER: WASSERMAN, ANTHONY I. DOCUMENT NUMBER: 5484 DOCUMENT DATE: 11/82 TYPE: TECHNICAL REPORT In Spring, 1982, a questionnaire was...VALIDATION AVAILABLE FROM: THE AUTHOR SPONSORS: U.S.A.F. ASD,WRIGHT-PATTERSON AFB, OH AN ADA LANGUAGE PRIMER, PART I SAIB, SABINA H. DOCUMENT NUMBER: 6214...PRIMER, PART II SAIB, SABINA H. DOCUMENT NUMBER: 6215 TYPE: JOURNAL ARTICLE BYTE, VOL 9, ISSUE 6, 14 P. This article is the second of a two-part

  3. Nif- Hup- mutants of Rhizobium japonicum.

    Science.gov (United States)

    Moshiri, F; Stults, L; Novak, P; Maier, R J

    1983-01-01

    Two H2 uptake-negative (Hup-) Rhizobium japonicum mutants were obtained that also lacked symbiotic N2 fixation (acetylene reduction) activity. One of the mutants formed green nodules and was deficient in heme. Hydrogen oxidation activity in this mutant could be restored by the addition of heme plus ATP to crude extracts. Bacteroid extracts from the other mutant strain lacked hydrogenase activity and activity for both of the nitrogenase component proteins. Hup+ revertants of the mutant strains regained both H2 uptake ability and nitrogenase activity. Images PMID:6874648

  4. Biochemical detection of E-ADA on Neospora caninum tachyzoites and the effects of a specific enzymatic inhibitor

    Directory of Open Access Journals (Sweden)

    Alexandre A. Tonin

    2015-01-01

    Full Text Available Objective. This study aimed to investigate the presence and activity of the ecto adenosine deaminase (E-ADA enzyme in tachyzoites of Neospora caninum (Nc-1 strain, as well as to assess the activity of a well-known E-ADA inhibitor, the deoxycoformycin. Materials and methods. The parasites were grown in cell culture, being subsequently separated in a pellet of tachyzoites, on which the E-ADA activity was tested using the concentrations 0 (control, 0.2, 0.4 and 0.8 mg mL-1. Results. The E-ADA showed high activity, progressively increasing its activity according to the enhancement of the protein concentration. The test was carried out with different concentrations of deoxycoformycin, showing that it was able to inhibit the E-ADA present on the free form of the parasite. Conclusions. Based on these results we conclude that the E-ADA is present on tachyzoites of N. caninum, and deoxycoformycin is able to inhibit this enzyme. In this sense, knowing the negative impact of N. caninum on reproductive issue in cattle (mainly abortion, might it is an alternative in order to deal with this parasitic infection.

  5. Object-oriented programming with mixins in Ada

    Science.gov (United States)

    Seidewitz, ED

    1992-01-01

    Recently, I wrote a paper discussing the lack of 'true' object-oriented programming language features in Ada 83, why one might desire them in Ada, and how they might be added in Ada 9X. The approach I took in this paper was to build the new object-oriented features of Ada 9X as much as possible on the basic constructs and philosophy of Ada 83. The object-oriented features proposed for Ada 9X, while different in detail, are based on the same kind of approach. Further consideration of this approach led me on a long reflection on the nature of object-oriented programming and its application to Ada. The results of this reflection, presented in this paper, show how a fairly natural object-oriented style can indeed be developed even in Ada 83. The exercise of developing this style is useful for at least three reasons: (1) it provides a useful style for programming object-oriented applications in Ada 83 until new features become available with Ada 9X; (2) it demystifies many of the mechanisms that seem to be 'magic' in most object-oriented programming languages by making them explicit; and (3) it points out areas that are and are not in need of change in Ada 83 to make object-oriented programming more natural in Ada 9X. In the next four sections I will address in turn the issues of object-oriented classes, mixins, self-reference and supertyping. The presentation is through a sequence of examples. This results in some overlap with that paper, but all the examples in the present paper are written entirely in Ada 83. I will return to considerations for Ada 9X in the last section of the paper.

  6. Control of protein synthesis in herpesvirus-infected cells: analysis of the polypeptides induced by wild type and sixteen temperature-sensitive mutants of HSV strain 17.

    Science.gov (United States)

    Marsden, H S; Crombie, I K; Subak-Sharpe, J H

    1976-06-01

    The polypeptides induced in cells infected with a Glasgow isolate of HSV-I (17 syn+) have been characterized by SDS polyacrylamide gel electrophoresis. Study of the kinetics of synthesis in three cell lines has detected a total of 52 polypeptides, 33 of which can be identified in polypeptide profiles of purified virions. These include six low mol. wt. polypeptides that have not been previously reported. Several polypeptides were labelled with glucosamine in infected BHK cells. The different polypeptide patterns obtained at permissive (31 degrees C) and nonpermissive (38 degrees C) temperature in cells infected with 16 temperature-sensitive (ts) mutants are reported. The effect of multiplicity of infection (m.o.i.) on the polypeptide profile has been examined for two of the DNA -ve mutants: below ten, the profile varied with the m.o.i. whereas above ten it was constant. All mutants were therefore examined at an m.o.i. of approx. 20. Mutants from the same complementation group showed very similar profiles. A number of general conclusions concerning control of protein synthesis in HSV infected cells can be made: (I) As most of the 16 ts mutants affected the synthesis of several or many polypeptides it follows that a large proportion of genome specifies controlling functions. (2) The high frequency with which some polypeptides were affected suggests they are at or near the terminus of biosynthetic pathways which are under multiple control. (3) Conversely, some polypeptides were affected with a low frequency suggesting that their synthesis is not dependent on the expression of many virus functions. (4) Several individual ts mutations lead to the synthesis of increased amounts of different large polypeptides. (5) Analysis of every band detectably affected by at least one ts mutation has disclosed nine classes of dependence relationship between polypeptide synthesis and the DNA phenotype of the mutants, illustrating that this relationship is complex and different for

  7. An organic acid-tolerant HAA1-overexpression mutant of an industrial bioethanol strain of Saccharomyces cerevisiae and its application to the production of bioethanol from sugarcane molasses.

    Science.gov (United States)

    Inaba, Takuya; Watanabe, Daisuke; Yoshiyama, Yoko; Tanaka, Koichi; Ogawa, Jun; Takagi, Hiroshi; Shimoi, Hitoshi; Shima, Jun

    2013-12-30

    Bacterial contamination is known as a major cause of the reduction in ethanol yield during bioethanol production by Saccharomyces cerevisiae. Acetate is an effective agent for the prevention of bacterial contamination, but it negatively affects the fermentation ability of S. cerevisiae. We have proposed that the combined use of organic acids including acetate and lactate and yeast strains tolerant to organic acids may be effective for the elimination of principally lactic acid bacterial (LAB) contamination. In a previous study employing laboratory S. cerevisiae strains, we showed that overexpression of the HAA1 gene, which encodes a transcriptional activator, could be a useful molecular breeding method for acetate-tolerant yeast strains. In the present study, we constructed a HAA1-overexpressing diploid strain (MATa/α, named ER HAA1-OP) derived from the industrial bioethanol strain Ethanol Red (ER). ER HAA1-OP showed tolerance not only to acetate but also to lactate, and this tolerance was dependent on the increased expression of HAA1 gene. The ethanol production ability of ER HAA1-OP was almost equivalent to that of the parent strain during the bioethanol production process from sugarcane molasses in the absence of acetate. The addition of acetate at 0.5% (w/v, pH 4.5) inhibited the fermentation ability of the parent strain, but such an inhibition was not observed in the ethanol production process using ER HAA1-OP.

  8. 耐甲氧西林表皮葡萄球菌 psm-mec 缺失突变株的构建%Construction of mutant strains of methicillin resistant Staphylococcus epidermidis with psm-mec gene deletion

    Institute of Scientific and Technical Information of China (English)

    杨永长; 胡洪华; 陈亮; 刘华; 喻华; 黄文芳

    2015-01-01

    Objective To construct mutant strains of methicillin resistant Staphylococcus epidermi-dis (MRSE) with psm-mec gene deletion and to investigate the function of psm-mec gene.Methods The drug sensitivity test and DNA sequence analysis were performed to screen out the tetracycline and chloram -phenicol sensitive clinical strains of MRSE , whose upstream and downstream sequences of psm-mec gene were identical to those of the Staphylococcus epidermidis reference strain RP62A.The recombinant plasmid pBT2-Δpsm-mec was constructed by using the fusion PCR and a temperature sensitive shuttle plasmid .After being identified , the plasmid was transformed into the Staphylococcus aureus RN4220 strain by electropora-tion, and then transformed into the selected clinical isolates of MRSE .The mutant strains of MRSE with psm-mec deletion were screened out and identified after homologous recombination .The differences in biofilm formation between the mutant and wild-type strains were analyzed for further elucidation the relationships be-tween the psm-mec gene and biofilm formation in MRSE strains .Results Three clinical MRSE isolates for the construction of mutant strains with psm-mec gene deletion were screened out and identified by using drug sensitivity test and sequence alignment analysis .The mutants constructed via homogenous recombination were screened out and identified .Compared with the corresponding wild-type strains, the three mutants with psm-mec gene deletion showed significantly decreased ability of biofilm formation , demonstrating that the psm-mec genes strains induced the biofilm formation of MRSE .Conclusion The Δpsm-mec mutant strains were successfully constructed .The psm-mec gene played an important role in the biofilm formation of Staphy-lococcus epidermdis.%目的:构建耐甲氧西林表皮葡萄球菌( MRSE)的psm-mec缺失突变株,并对psm-mec的功能进行初步研究。方法运用药敏试验、DNA序列分析技术筛选psm-mec上下游序

  9. Growth, physicochemical properties, and morphogenesis of Chinese wild-type PRV Fa and its gene-deleted mutant strain PRV SA215

    Directory of Open Access Journals (Sweden)

    Tang Shanhu

    2011-06-01

    Full Text Available Abstract Background PRV Fa is common in China and causes most of the pseudorabies in the pig industry. A PRV SA215 strain with deleted gE, gI, and TK genes was constructed to develop a commercial attenuated live vaccine. However, the physicochemical properties, growth pattern, penetration kinetics, and morphogenesis of the PRV SA215 and its parental PRV Fa strain are unclear. Results A series of experiments were conducted to characterize both strains and provide more information. PRV Fa and PRV SA215 were found to have similar penetration patterns, with about 5 min half-time of penetration. The SA215 strain exhibited a slight delay in entry compared with PRV Fa. In the one-step growth test, the titers of the SA215 strain were first detected at 8 h, rapidly increased, and peaked at 12 h. A plateau was formed between 12-36 h of culturing. PRV SA215 showed delayed replication and approximately 10-30-fold lower titers during 0-16 h of culturing compared with the PRV-Fa strain. After 16 h, the PRV Fa titers dramatically decreased, whereas those of PRV SA215 were prolonged to 36 h and reached a titer value equal to that of PRV Fa and then decreased. Both strains were sensitive to both heat and acid-alkali treatments; however, PRV Fa was relatively more stable to heat treatment than PRV SA215. Both strains could propagate in the cultures with pH values from 5.0 to 9.0. Cultures with pH below 3.0 or above 11.0 were fatal to both strains. Both strains had considerable resistance to freeze-thawing treatments. Morphogenetic investigations showed that typical phases in the maturation pathway were observed in the PRV Fa-infected PK15 cells, whereas secondary envelopment was not observed in the PRV SA215 strain. Instead, capsid aggregations with concomitants of electrodense materials were observed. Conclusions These results suggest that PRV SA215 is a promising strain for vaccine development

  10. Properties of S-adenosyl-L-methionine:macrocin O-methyltransferase in extracts of Streptomyces fradiae strains which produce normal or elevated levels of tylosin and in mutants blocked in specific O-methylations.

    Science.gov (United States)

    Seno, E T; Baltz, R H

    1981-01-01

    An efficient assay for S-adenosyl-L-methionine:macrocin O-methyltransferase, the enzyme which carries out the terminal step in tylosin biosynthesis, is described. Macrocin O-methyltransferase requires Mg2+ and S-adenosyl-L-methionine for activity, has a temperature optimum of about 31 degrees C, and has a pH optimum of 7.5 to 8.2. Macrocin O-methyltransferase specifically converts macrocin to tylosin by O-methylation of the 3" ' position of macrocin. In vitro methylation studies with extracts from a tylosin-producing Streptomyces fradiae strain and from mutant strains blocked in 2" '- or 3" '-O-methylations indicated that: (i) the 2" '- and 3" '-O-methylations occur after 6-deoxy-D-allose is attached to the macrolide ring; (ii) the 2" '- and 3" '-O-methylations are carried out by separate enzymes; and (iii) the 2" '-O-methylation precedes the 3" '-O-methylation. Macrocin O-methyltransferase was inhibited by high levels of its substrate, macrocin, by its product, tylosin, and by other tylosin analogs which contained mycinose or demethyl analogs of mycinose. Macrocin O-methyltransferase was produced early in the tylosin fermentation cycle by S. fradiae and preceded the onset of rapid tylosin biosynthesis by about 24 h. The enzyme specific activity reached maximum at about 72 h and then slowly declined. A mutant strain of S. fradiae selected for increased tylosin production synthesized macrocin O-methyltransferase more rapidly and accumulated a higher enzyme specific activity than a wild-type strain. PMID:7305323

  11. Expression and Immunogenicity of a Mutant Diphtheria Toxin Molecule, CRM197, and Its Fragments in Salmonella typhi Vaccine Strain CVD 908-htrA

    Science.gov (United States)

    Orr, Nadav; Galen, James E.; Levine, Myron M.

    1999-01-01

    Mutant diphtheria toxin molecule CRM197 and fragments thereof were expressed in attenuated Salmonella typhi CVD 908-htrA, and the constructs were tested for their ability to induce serum antitoxin. Initially, expressed proteins were insoluble, and the constructs failed to induce neutralizing antitoxin. Soluble CRM197 was expressed at low levels by utilizing the hemolysin A secretion system from Escherichia coli. PMID:10417208

  12. Locating a modifier gene of Ovum mutant through crosses between DDK and C57BL/6J inbred strains in mice

    Indian Academy of Sciences (India)

    JING TAN; GEN DI SONG; JIA SHENG SONG; SHI HAO REN; CHUN LI LI; ZHEN YU ZHENG; WEI DONG ZHAO

    2016-06-01

    A striking infertile phenotype has been discovered in the DDK strain of mouse. The DDK females are usually infertile when crossed with males of other inbred strains, whereas DDK males exhibit normal fertility in reciprocal crosses. This phenomenon is caused by mutation in the ovum (Om) locus on chromosome 11 and known as the DDK syndrome. Previously, some research groups reported that the embryonic mortality deviated from the semilethal rate in backcrosses between heterozygous (Om/+) females and males of other strains. This embryonic mortality exhibited an aggravated trend with increasing background genes of other strains. These results indicated that some modifier genes of Om were present in other strains. In the present study, a population of N 2(Om/+) females from the backcrosses between C57BL/6J (B6) and F1(B6♀×DDK♂) was used to map potential modifier genes of Om. Quantitative trait locus showed that a major locus, namely Amom1 (aggravate modifier gene of Om 1), was located at the middle part of chromosome 9 in mice. The Amom1 could increase the expressivity of Om gene, thereby aggravating embryonic lethality when heterozygous (Om/+)females mated with males of B6 strain. Further, the 1.5 LOD-drop analysis indicated that the confidence interval was between 37.54 and 44.46 cM,∼6.92 cM. Amom1 is the first modifier gene of Om in the B6 background.

  13. Construction and Characterization of Campylobacter jejuni flhA Mutant Strain%空肠弯曲菌flhA突变株的构建及其功能研究

    Institute of Scientific and Technical Information of China (English)

    惠星星; 李烨; 王小元

    2011-01-01

    flhA, encoded by the gene flhA, is an important component of the flagellar export apparatus of Campylobacter jejuni. Here we constructed an flhA mutant strain HXW001.Compared with that of the wild type, the flhA mutant cell could grow well but lack flagella, the motility of the mutant cells was lost, and the ability of the mutant cells for the formation of biofilm and autoagglutination also decreased. In addition, it was found that the expression of the flagellin gene flaA was affected by flhA. These findings indicated that flhA was the molecular basis of flagellar synthesis and motility of Campylobacter jejuni and that flhA was closely related to pathogenicity of Carnpylobacter jejuni.%flhA是空肠弯曲茵鞭毛输出装置的关键基因,通过构建Campylobacterjejuni flhA突变株HXW001,进行毒力相关表型研究和分析.结果显示HXW001生长性能稳定,但其鞭毛和运动能力丧失,生物膜形成和自身凝集现象明显下降.RT-PCR实验证明flhA对鞭毛丝主要结构蛋白基因flaA的表达有一定的调控功能.研究表明flhA是空肠弯曲茵鞭毛生成和运动能力重要的分子基础,与空肠弯曲菌致病性密切有关.

  14. Construction and characteristic of srtA gene mutant strain of Streptococcus suis 2%猪链球菌2型srtA基因缺失菌株的构建及生物学特性

    Institute of Scientific and Technical Information of China (English)

    吴涛; 常海涛; 谭臣; 付婷; 司有辉; 贝为成; 陈焕春

    2009-01-01

    In the present study,srtA gene mutant strain was constructed by using the thermo-sensitive suicide vector pSET4s and confirmed by PCR and Southern blotting.The results showed that the construction of the mutant strain was successful,named SC211.In addition complementation mutant strain was constructed by using the E.coli/Streptococcus shuttle vector pAT18,named SC212.The characteristic of SC211 and SC212 was further researched.The virulence of different strains was determined by animal infection,which demonstrated that the virulence was decreased clearly when the srtA gene knocked out.The virulence of the mutant was restored when strain mediated by plasmid-containing the srtA gene.However,it could not reach the level of the wild type.The hemolytic activity of the srtA gene mutant strain and the complementation strain had no difference when compared with the wild type strain.The adherence to the Hep2 cell of the srtA gene mutant strain degraded obviously,and the adherence to the Hep2 cell of the complementation strain had no obvious difference compared with the wild type.%扩增了srtA基因的上、下游同源臂P1和P2及其全长序列,利用温度敏感型"自杀性"质粒pSET4s构建了重组质粒pSET4s-P1-P2,并将该质粒电转化入野生菌株SS2(SC21)中,通过抗生素和温度双重筛选,得到srtA基因缺失菌株,命名SC211.同时,将srtA基因定向插入穿梭质粒pAT18,构建穿梭质粒pAT18-srtA,并将该质粒电转入srtA基因缺失菌株SC211中,通过抗生素筛选,得到质粒介导的srtA基因互补菌株SC212.通过PCR、South-ern blotting等对缺失突变菌株和互补菌株进行了鉴定.对基因缺失突变菌株和回复菌株传代培养遗传稳定性试验结果显示,缺失突变菌株和互补菌株能够稳定遗传.比较了基因缺失突变菌株、互补菌株及野生菌株的生长特性、溶血活性、细胞粘附特性,结果表明,3个菌株的生长速度、溶血活性没有

  15. Association of G22A and A4223C ADA1 gene polymorphisms and ADA activity with PCOS.

    Science.gov (United States)

    Salehabadi, Mahshid; Farimani, Marzieh; Tavilani, Heidar; Ghorbani, Marzieh; Poormonsefi, Faranak; Poorolajal, Jalal; Shafiei, Gholamreza; Ghasemkhani, Neda; Khodadadi, Iraj

    2016-06-01

    Adenosine deaminase-1 (ADA1) regulates the concentration of adenosine as the main modulator of oocyte maturation. There is compelling evidence for the association of ADA1 gene polymorphisms with many diseases but the importance of ADA1 polymorphisms in polycystic ovary syndrome (PCOS) has not been studied before. This study investigates serum total ADA activity (tADA), ADA1 and ADA2 isoenzyme activities, and genotype and allele frequencies of G22A and A4223C polymorphisms in healthy and PCOS women. In this case-control study 200 PCOS patients and 200 healthy women were enrolled. Genomic DNA was extracted from whole blood and the PCR-RFLP technique was used to determine the G22A and A4223C variants. The genotype frequencies were calculated and the association between polymorphic genotypes and enzyme activities were determined. tADA activity was significantly lower in the PCOS group compared with the control group (27.76±6.0 vs. 39.63±7.48, respectively). PCOS patients also showed reduced activity of ADA1 and ADA2. PCOS was not associated with G22A polymorphism whereas AA, AC, and CC genotypes of A4223C polymorphism were found distributed differently between the control and the PCOS women where the C allele showed a strong protective role for PCOS (odds ratio=1.876, p=0.033). The present study for the first time showed that lower ADA activity may be involved in pathogenesis of PCOS by maintaining a higher concentration of adenosine affecting follicular growth. As a novel finding, we also showed great differences in genotype distribution and allele frequencies of A4223C polymorphism between groups indicating a protective role for C allele against PCOS. AbbreviationsADA: adenosine deaminase PCOS: polycystic ovary syndrome PCR-RFLP: polymerase chain reaction-restriction fragment length polymorphism tADA: total adenosine deaminase.

  16. ada: An R Package for Stochastic Boosting

    Directory of Open Access Journals (Sweden)

    Mark Culp

    2006-09-01

    Full Text Available Boosting is an iterative algorithm that combines simple classification rules with ‘mediocre’ performance in terms of misclassification error rate to produce a highly accurate classification rule. Stochastic gradient boosting provides an enhancement which incorporates a random mechanism at each boosting step showing an improvement in performance and speed in generating the ensemble. ada is an R package that implements three popular variants of boosting, together with a version of stochastic gradient boosting. In addition, useful plots for data analytic purposes are provided along with an extension to the multi-class case. The algorithms are illustrated with synthetic and real data sets.

  17. ada: An R Package for Stochastic Boosting

    Directory of Open Access Journals (Sweden)

    Mark Culp

    2006-09-01

    Full Text Available Boosting is an iterative algorithm that combines simple classification rules with "mediocre" performance in terms of misclassification error rate to produce a highly accurate classification rule. Stochastic gradient boosting provides an enhancement which incorporates a random mechanism at each boosting step showing an improvement in performance and speed in generating the ensemble. ada is an R package that implements three popular variants of boosting, together with a version of stochastic gradient boosting. In addition, useful plots for data analytic purposes are provided along with an extension to the multi-class case. The algorithms are illustrated with synthetic and real data sets.

  18. Software engineering and the role of Ada: Executive seminar

    Science.gov (United States)

    Freedman, Glenn B.

    1987-01-01

    The objective was to introduce the basic terminology and concepts of software engineering and Ada. The life cycle model is reviewed. The application of the goals and principles of software engineering is applied. An introductory understanding of the features of the Ada language is gained. Topics addressed include: the software crises; the mandate of the Space Station Program; software life cycle model; software engineering; and Ada under the software engineering umbrella.

  19. An Adaptation of the ADA Language for Machine Generated Compilers.

    Science.gov (United States)

    1980-12-01

    Ada Augusta, Lady Lovelace , the daughter of the poet, Lord Byron, and Charles Babbage’s programmer.# 2UNIX is a Trademark/Service Mark of the Bell...AN ADAPTATION OF THE ADA LANGUAGE FOR MACHINE GENERATED COMPILE-ETC(U) JNLSIIO DEC AG M A ROGERS, L P MYERS 7k .A9 22NVLPSTRDASHOOLMONEREYCAF EE9...mmhhhhhhmhhhhlLEhhhhhmmh LEV EU NAVAL POSTGRADUATE SCHOOL Monterey, California DTIC ~ELECTEf All 0 3 198 /12 )THESIS 7 ,AN *DAPTATION OF THE ADA

  20. Its Ada: An Intelligent Tutoring System for the ADA Programming Language

    Science.gov (United States)

    1991-12-01

    TUTR, available through the Ada Repository at White Sands Missile Range in Alamagordo, New Mexico , is an application in computer- assisted instruction...same time as declaring it, we write: MYCAR :CARTYPE := ("Cl23XYZ","Ford Fiesta GL ",1986,840,30.0); We can also use record aggregates in assignments

  1. Degradation of n-Haloalkanes and α,ω-Dihaloalkanes by Wild-Type and Mutants of Acinetobacter sp. Strain GJ70

    NARCIS (Netherlands)

    Janssen, Dick B.; Jager, Dick; Witholt, Bernard

    1987-01-01

    A 1,6-dichlorohexane-degrading strain of Acinetobacter sp. was isolated from activated sludge. The organism could grow with and quantitatively release halide from 1,6-dichlorohexane, 1,9-dichlorononane, 1-chloropentane, 1-chlorobutane, 1-bromopentane, ethylbromide, and 1-iodopropane. Crude extracts

  2. Implementation of a production Ada project: The GRODY study

    Science.gov (United States)

    Godfrey, Sara; Brophy, Carolyn Elizabeth

    1989-01-01

    The use of the Ada language and design methodologies that encourage full use of its capabilities have a strong impact on all phases of the software development project life cycle. At the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC), the Software Engineering Laboratory (SEL) conducted an experiment in parallel development of two flight dynamics systems in FORTRAN and Ada. The differences observed during the implementation, unit testing, and integration phases of the two projects are described and the lessons learned during the implementation phase of the Ada development are outlined. Included are recommendations for future Ada development projects.

  3. Understanding the Adoption of Ada: A Field Study Report

    Science.gov (United States)

    1989-08-01

    a name change. The name Ada comes from Augusta Ada Byron, Countess of Lovelace , Charles Babbage’s colleague, and according to some, the first computer...Adoption of Ada : * 1 A Field Study Report A Gordon N. Smith Wesley M. Cohen William E. Hefley Daniel A. Levinthal. August 1989 E DTIC *ie jApproved f or...Puib1I release; -A’Djqtribution Unbmtod 0 (3 134 154 Technical Report 0 SEI-88-TR-28 ESD-TR-88-37 August 1989 Understanding the Adoption of Ada : A Field

  4. Ada and the rapid development lifecycle

    Science.gov (United States)

    Deforrest, Lloyd; Gref, Lynn

    1991-01-01

    JPL is under contract, through NASA, with the US Army to develop a state-of-the-art Command Center System for the US European Command (USEUCOM). The Command Center System will receive, process, and integrate force status information from various sources and provide this integrated information to staff officers and decision makers in a format designed to enhance user comprehension and utility. The system is based on distributed workstation class microcomputers, VAX- and SUN-based data servers, and interfaces to existing military mainframe systems and communication networks. JPL is developing the Command Center System utilizing an incremental delivery methodology called the Rapid Development Methodology with adherence to government and industry standards including the UNIX operating system, X Windows, OSF/Motif, and the Ada programming language. Through a combination of software engineering techniques specific to the Ada programming language and the Rapid Development Approach, JPL was able to deliver capability to the military user incrementally, with comparable quality and improved economies of projects developed under more traditional software intensive system implementation methodologies.

  5. The ADAS inner solar system project

    Science.gov (United States)

    Hoffmann, Martin; Pignata, Giuliano; Barbieri, Cesare; Bertini, Ivano; Calvani, Massimo; Claudi, Riccardo; Hahn, Gerhard; Magrin, Sara; Mottola, Stefano; Neukum, Gerhard

    2002-11-01

    ADAS, the Asiago-DLR Asteroid Survey, is a joint program between the Department of Astronomy and Astronomical Observatory of Padova and the DLR Berlin, dedicated to the search of asteroids. The observations are made with a 67/92 cm Schmidt Telescope on Cima Ekar, near Asiago, in northern Italy. A 2K×2K CCD camera provided by the DLR is in use, mostly in Time Delay Integration mode. The camera has a field of 0.67 square degrees and can reach a limiting magnitude V ~ 21.0 in 3 minutes of exposure time. Specific search programs, in particular for objects permanently inside the orbit of the Earth (IEOs), have been started. A simulation of the performance of the IEO survey based on the model population from Bottke et al. shows that the discovery of a one-digit number of IEOs may be possible with the layout and equipment of the ADAS survey with a couple of years of operation.

  6. Transferring data objects: A focused Ada investigation

    Science.gov (United States)

    Legrand, Sue

    1988-01-01

    The use of the Ada language does not guarantee that data objects will be in the same form or have the same value after they have been stored or transferred to another system. There are too many possible variables in such things as the formats used and other protocol conditions. Differences may occur at many different levels of support. These include program level, object level, application level, and system level. A standard language is only one aspect of making a complex system completely homogeneous. Many components must be standardized and the various standards must be integrated. The principal issues in providing for interaction between systems are of exchanging files and data objects between systems which may not be compatible in terms of their host computer, operating system or other factors. A typical resolution of the problem of invalidating data involves at least a common external form, for data objects and for representing the relationships and attributes of data collections. Some of the issues dealing with the transfer of data are listed and consideration is given on how these issues may be handled in the Ada language.

  7. Use of flow cytometry for the adhesion analysis of Streptococcus pyogenes mutant strains to epithelial cells: investigation of the possible role of surface pullulanase and cysteine protease, and the transcriptional regulator Rgg

    Directory of Open Access Journals (Sweden)

    Finne Jukka

    2006-02-01

    Full Text Available Abstract Background Flow cytometry based adherence assay is a potentially powerful but little used method in the study of bacterial binding to host structures. We have previously characterized a glycoprotein-binding activity in Streptococcus pyogenes called 'strepadhesin' binding to thyroglobulin, submaxillar mucin, fetuin and asialofetuin. We have identified surface-associated pullulanase (PulA and cysteine protease (SpeB as carriers of strepadhesin activity. In the present paper, we investigated the use of flow cytometry as a method to study the binding of Rgg, SpeB and PulA knock-out strains to cultured human epithelial cells. Results Streptococcal mutants were readily labelled with CFDA-SE and their binding to epithelial cells could be effectively studied by flow cytometry. A strain deficient in Rgg expression showed increased binding to the analyzed epithelial cell lines of various origin. Inactivation of SpeB had no effect on the adhesion, while PulA knock-out strains displayed decreased binding to the cell lines. Conclusion These results suggest that the flow cytometric assay is a valuable tool in the analysis of S. pyogenes adherence to host cells. It appears to be an efficient and sensitive tool for the characterization of interactions between the bacteria and the host at the molecular level. The results also suggest a role for Rgg regulated surface molecules, like PulA, in the adhesion of S. pyogenes to host cells.

  8. Experimental infection of commercial layers with wild or attenuated Salmonella Gallinarum mutant strains: anatomic pathology, total blood cell count and serum protein levels

    Directory of Open Access Journals (Sweden)

    KO Garcia

    2013-06-01

    Full Text Available The aim of the present study was to comparatively evaluate hemogram, blood serum components and anatomopathologic alterations in commercial layers experimentally challenged with an attenuated vaccine candidate strain (SG∆cobS∆cbiA and other two pathogenic strains (SGDcobS and SGNalr of Gallinarum (SG. In total, 280 commercial layers were randomly divided into 4 groups (G1, G2, G3 and G4. At five days of age, birds from groups G1 received approximately 107 colony forming units (CFU of SGDcobS; meanwhile birds from group G2 and G3 received the same dose of SGNalr and SG∆cobS∆cbiA, respectively. Birds from G4 were not infected. At 24 hours before (DBI and 24 hours after (1 DAI, and three (3 DAI, five (5 DAI, seven (7 DAI ten (10 DAI, and fifteen (15 DAI days after the infection, 10 birds of each group were humanely killed and blood samples collected to hematological and serum tests. Samples of liver, spleen, thymus, bursa of Fabricius, kidney and heart were also collected for the histological examination. Birds inoculated with SGDcobS and SGNalr showed similar alterations in hemogram, blood serum components and anatomopathologic exams. On the other hand, the exams of birds inoculated with SG∆cobS∆cbiA strain were similar to those of the uninfected birds. However, changes could be noticed in levels of uric acid and cholesterol during the course of the infection of birds from G3. Decrease in levels of light IgG 3 DAI was also observed in birds from this group. Pyknosis in kidney cells was a microscopic alteration found in birds from G3. Further studies must be done to verify if these alterations will not interfere in the performance of the vaccinate birds with SG∆cobS∆cbiA strain.

  9. LuxS基因缺失的变形链球菌突变株的构建及鉴定%Construction and identification of a LuxS-deleted mutant strain of S.mutans

    Institute of Scientific and Technical Information of China (English)

    于丹妮; 韩福胜; 韩玉植; 陈杰

    2008-01-01

    目的 通过同源重组法构建LuxS基因缺失的变形链球菌(Streptococcus mutans)突变株.方法 运用基因同源重组方法将红霉素抗性基因(Eymr)连接到PCR扩增LuxS基因两端区域产生的2个基因片段之间,并共同插入到pUCl9载体的多克隆位点中,构建出带红霉素抗性标志的缺失突变载体pUCluxKO.将突变载体转化到含完整LuxS基因的突变受体变形链球菌标准株中,红霉素筛选出LuxS基因缺失的变形链球菌突变株,并经PCR、生物荧光检测及DNA测序鉴定.结果 构建的突变载体经限制性内切核酸酶酶切分析显示,产生的条带与设计结果完全一致.PCR方法扩增突变株LuxS和Eymr基因显示,LuxS基因已被完整敲除掉,经生物荧光检测,突变株不能诱导哈氏弧菌(Vibrio harveyi)BBl70的生物发光,说明不能产生信号分子AI-2(autoinducer-2).DNA测序证实筛选得到了LuxS基因缺失的变形链球菌突变株.连续传代培养后证实,变形链球菌LuxS基因突变株具有良好的稳定性.结论 成功构建出LuxS基因缺失的变形链球菌突变株,为研究LuxS基因对变形链球菌致龋毒力的影响奠定了基础.%Objective To knock out the entire LuxS gene of Streptococcus mutans UA159 strain via homologous recombination and construct a LuxS-deleted mutant strain of S.mutans.Methods The erythromycin resistance gene(Eymr)was inserted between the two DNA fragments located in the upper and downstream of LuxS gene that had been amplified by PCR.Then the two DNA fragments along with the inserted Eymr were engineered into pUCl9 plasmid to construct the recombination plasmid pUCluxKO.Electrotransformation of S. mutans cells with pUCluxKO-mutant resulted in the isolation of erythromycin resistant S.mutans,transformants,which was then subjected to polymerase chain reaction,Vibrio harveyi BBl70 luminescence bioassay and sequencing analysis.Results Restriction endonuclease analysis showed that pUCluxKOmutant vector

  10. Cellulase production by two mutant strain of Trichoderma longibranchiatum QM9414 and Rut C30; Produccion de celulasas a partir de dos cepas hiperproductoras de trichoderma longibranchiatum Qm9-41 4 y Rut C30

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, M. J.

    1991-07-01

    Native or pretreated biomass from Onopordum nervosum Boiss, has been examined as candidate feedstock for cellulase production by two mutant strain of Trichoderma Ionqibrachiatum QM9414 and Rut C30. Batch cultivation methods were evaluated and compared with previous experiments using ball-milled, crystalline cellulose (Solka floc). Batch cultivation of T. Ionqibrachiatum Rut C30 on 5% (w/v) acid pretreated O. nervosum biomass yielded enzyme productivities and activities comparable to those obtained on Solka floc. However, the overall enzyme production performance was lower than on Solka floc at comparable cellulose concentrations. This fact may be due to the accumulation of pretreated by products and lignin in the ferment. (Author) 40 refs.

  11. Factors affecting growth and antibiotic susceptibility of Helicobacter pylori: effect of pH and urea on the survival of a wild-type strain and a urease-deficient mutant.

    Science.gov (United States)

    Sjöström, J E; Larsson, H

    1996-06-01

    This study investigated how pH and the presence of urea affect the survival and growth of Helicobacter pylori and whether these factors affect susceptibility to antibiotics in vitro. The viability of a wild-type strain and a urease-deficient mutant of H. pylori was studied after incubation for 1 h in buffers at different pH values at 37 degrees C under microaerophilic conditions. Viable counts were not affected at pH 5 and pH 7. In buffer at pH 3, there were no viable organisms, but urea (6.25 mM) protected the wild-type strain, which survived well. At pH 9, urea further reduced the viability of H. pylori and flurofamide almost abolished the effect of urea on the wild-type strain. Neither urea nor flurofamide affected the viability of the urease-deficient mutant under the same conditions. Growth was also pH dependent and was enhanced in shake-cultures. At pH 5, urea supported growth of the wild-type strain, but at pH 7 a toxic effect on the bacteria was observed. Growth of H. pylori at pH 5.9 was poor, and susceptibility to amoxycillin, erythromycin and clarithromycin was markedly less than at pH 7.2 and 7.9. The bactericidal activities of metronidazole and tetracycline were similar at the different pH values studied. At neutral pH the killing rates of amoxycillin and clarithromycin were growth rate dependent. Susceptibility to metronidazole was enhanced in stationary cultures. The interaction obtained between the proton pump inhibitor, omeprazole, and amoxycillin at pH 7 was of additive type. These results suggest that pH and growth conditions may be important in the antibacterial efficacy of different antibiotics in vivo and also provide a possible explanation for the potentiating effect of omeprazole with antibiotics in the treatment of H. pylori infections.

  12. 59 FR- Realty Action; Ada and Owyhee, ID

    Science.gov (United States)

    1994-05-03

    ...-332A-02; IDI-29516] Realty Action; Ada and Owyhee, ID AGENCY: Bureau of Land Management, Interior. ACTION: Notice of Realty Action--IDI-29516; Exchange of public and private lands in Ada and Owyhee.... Containing 640 acres, more or less, in Owyhee County. The purpose of this exchange is to dispose of...

  13. Fine-Tuning ADAS Algorithm Parameters for Optimizing Traffic ...

    Science.gov (United States)

    With the development of the Connected Vehicle technology that facilitates wirelessly communication among vehicles and road-side infrastructure, the Advanced Driver Assistance Systems (ADAS) can be adopted as an effective tool for accelerating traffic safety and mobility optimization at various highway facilities. To this end, the traffic management centers identify the optimal ADAS algorithm parameter set that enables the maximum improvement of the traffic safety and mobility performance, and broadcast the optimal parameter set wirelessly to individual ADAS-equipped vehicles. After adopting the optimal parameter set, the ADAS-equipped drivers become active agents in the traffic stream that work collectively and consistently to prevent traffic conflicts, lower the intensity of traffic disturbances, and suppress the development of traffic oscillations into heavy traffic jams. Successful implementation of this objective requires the analysis capability of capturing the impact of the ADAS on driving behaviors, and measuring traffic safety and mobility performance under the influence of the ADAS. To address this challenge, this research proposes a synthetic methodology that incorporates the ADAS-affected driving behavior modeling and state-of-the-art microscopic traffic flow modeling into a virtually simulated environment. Building on such an environment, the optimal ADAS algorithm parameter set is identified through an optimization programming framework to enable th

  14. Alma Flor Ada and the Quest for Change

    Science.gov (United States)

    Manna, Anthony, L.; Hill, Janet; Kellogg, Kathy

    2004-01-01

    Alma Flor Ada, a folklorist, novelist, scholar, teacher, and children's book author has passionate dedication to education for social justice, equality, and peace. As a faculty member at the University of San Francisco, Ada has developed programs that help students and others transform their lives and has written several bilingual legends and…

  15. Ada (Trademark) Tasking and Exceptions: A Formal Definition.

    Science.gov (United States)

    1985-01-01

    handlerjist exception- bandler -jead sequence...of-statements E14) exceptionjiandlerjlist -. exceptionji andler..head sequence..of..statements E15...Weatherly, Richard M., A Messale-Based Kernel to Support Ada Tasking, Proceedings of the IEEE Computer 06; Society 1984 Conference on Ada

  16. Service dogs, psychiatric hospitalization, and the ADA.

    Science.gov (United States)

    Muramatsu, Russ S; Thomas, Kelly Jones; Leong, Stephanie L; Ragukonis, Frank

    2015-01-01

    A service dog is defined as "any dog that is individually trained to do work or perform tasks for the benefit of an individual with a disability, including a physical, sensory, psychiatric, intellectual, or other mental disability." Some psychiatric patients may depend on a service dog for day-to-day functioning. The Americans with Disabilities Act (ADA) established certain rights and responsibilities for individuals with disabilities and health care providers. Psychiatric hospitalization of a patient with a service dog may pose a problem and involves balancing the requirement to provide safe and appropriate psychiatric care with the rights of individuals with disabilities. This Open Forum examines issues that arise in such circumstances, reviews the literature, and provides a foundation for the development of policies and procedures.

  17. Assessment of Metabolic Changes in Mycobacterium smegmatis Wild-Type and alr Mutant Strains: Evidence of a New Pathway of d-Alanine Biosynthesis.

    Science.gov (United States)

    Marshall, Darrell D; Halouska, Steven; Zinniel, Denise K; Fenton, Robert J; Kenealy, Katie; Chahal, Harpreet K; Rathnaiah, Govardhan; Barletta, Raúl G; Powers, Robert

    2017-03-03

    In mycobacteria, d-alanine is an essential precursor for peptidoglycan biosynthesis. The only confirmed enzymatic pathway to form d-alanine is through the racemization of l-alanine by alanine racemase (Alr, EC 5.1.1.1). Nevertheless, the essentiality of Alr in Mycobacterium tuberculosis and Mycobacterium smegmatis for cell survivability in the absence of d-alanine has been a point of controversy with contradictory results reported in the literature. To address this issue, we examined the effects of alr inactivation on the cellular metabolism of M. smegmatis. The M. smegmatis alr insertion mutant TAM23 exhibited essentially identical growth to wild-type mc(2)155 in the absence of d-alanine. NMR metabolomics revealed drastically distinct phenotypes between mc(2)155 and TAM23. A metabolic switch was observed for TAM23 as a function of supplemented d-alanine. In the absence of d-alanine, the metabolic response directed carbon through an unidentified transaminase to provide the essential d-alanine required for survival. The process is reversed when d-alanine is available, in which the d-alanine is directed to peptidoglycan biosynthesis. Our results provide further support for the hypothesis that Alr is not an essential function of M. smegmatis and that specific Alr inhibitors will have no bactericidal action.

  18. Isolation of a novel mutant from Bacillus subtilis natto.

    Science.gov (United States)

    Yoshida, Kazuo

    2006-01-01

    For the construction of strains with full probiotics function in intestines, deoxycholate resistant mutants were isolated from Bacillus subtilis natto. The partial characterization of the mutants was carried out and described.

  19. Construction and Identification of omp31-Deleted Mutant of Brucella Standard Strain 16M%布鲁氏菌16M△omp31基因缺失株的构建与鉴定

    Institute of Scientific and Technical Information of China (English)

    王慧; 张亚丽; 王远志; 陈创夫; 任晓丽

    2013-01-01

    To construct the omp31 deletion mutant of Brucella melitensis 16M,the upstream and downstream of the omp31 gene and SacB gene were amplified by PCR from Brucella melitensis 16M and Bacillus subtilis. After constructing omp31-SacB re-combinant fragment into plasmid 18-T simple vector, the suicide plasmid pGEM-7zf+-△omp31-SacB was further obtained and transformed into Brucella melitensis 16M by electroporation. The Aomp31 mutant strain was screened out by homologous recombination and its stability was detected by continuous bacteria culture. The results showed that Brucella melitensis 16M △omp31 mutant strain was successfully generated and reversion was not observed in 15 generations. This research lays a foundation of further study on the anti-apoptosis mechanism and construction of new types of vaccines of Brucella.%为了构建布鲁氏菌16M△omp31基因缺失株,采用PCR方法分别从亲本株16 M上扩增omp31基因的侧翼看序列及枯草芽孢杆菌SacB基因,并将所得片段与pMD18-T载体相连并测序,利用双酶切的方法分别将其连入自杀载体pGEM-7zf+,获得亚克隆pGEM-7zf+-△omp31-SacB.将所构建好的自杀载体通过电转化入布鲁氏菌16M感受态细胞中,经2次同源重组后筛选出16M△omp31基因缺失株,并对获得缺失株进行遗传稳定性检测.结果显示:成功获得布鲁氏菌16 M△omp31基因缺失株,该缺失株在15代内未发生回复性突变.本研究为今后研究布鲁氏菌抗凋亡机制奠定基础.

  20. Altered antibiotic transport in OmpC mutants isolated from a series of clinical strains of multi-drug resistant E. coli.

    Science.gov (United States)

    Lou, Hubing; Chen, Min; Black, Susan S; Bushell, Simon R; Ceccarelli, Matteo; Mach, Tivadar; Beis, Konstantinos; Low, Alison S; Bamford, Victoria A; Booth, Ian R; Bayley, Hagan; Naismith, James H

    2011-01-01

    Antibiotic-resistant bacteria, particularly gram negative species, present significant health care challenges. The permeation of antibiotics through the outer membrane is largely effected by the porin superfamily, changes in which contribute to antibiotic resistance. A series of antibiotic resistant E. coli isolates were obtained from a patient during serial treatment with various antibiotics. The sequence of OmpC changed at three positions during treatment giving rise to a total of four OmpC variants (denoted OmpC20, OmpC26, OmpC28 and OmpC33, in which OmpC20 was derived from the first clinical isolate). We demonstrate that expression of the OmpC K12 porin in the clinical isolates lowers the MIC, consistent with modified porin function contributing to drug resistance. By a range of assays we have established that the three mutations that occur between OmpC20 and OmpC33 modify transport of both small molecules and antibiotics across the outer membrane. This results in the modulation of resistance to antibiotics, particularly cefotaxime. Small ion unitary conductance measurements of the isolated porins do not show significant differences between isolates. Thus, resistance does not appear to arise from major changes in pore size. Crystal structures of all four OmpC clinical mutants and molecular dynamics simulations also show that the pore size is essentially unchanged. Molecular dynamics simulations suggest that perturbation of the transverse electrostatic field at the constriction zone reduces cefotaxime passage through the pore, consistent with laboratory and clinical data. This subtle modification of the transverse electric field is a very different source of resistance than occlusion of the pore or wholesale destruction of the transverse field and points to a new mechanism by which porins may modulate antibiotic passage through the outer membrane.

  1. Altered Antibiotic Transport in OmpC Mutants Isolated from a Series of Clinical Strains of Multi-Drug Resistant E. coli

    Science.gov (United States)

    Ceccarelli, Matteo; Mach, Tivadar; Beis, Konstantinos; Low, Alison S.; Bamford, Victoria A.; Booth, Ian R.; Bayley, Hagan; Naismith, James H.

    2011-01-01

    Antibiotic-resistant bacteria, particularly Gram negative species, present significant health care challenges. The permeation of antibiotics through the outer membrane is largely effected by the porin superfamily, changes in which contribute to antibiotic resistance. A series of antibiotic resistant E. coli isolates were obtained from a patient during serial treatment with various antibiotics. The sequence of OmpC changed at three positions during treatment giving rise to a total of four OmpC variants (denoted OmpC20, OmpC26, OmpC28 and OmpC33, in which OmpC20 was derived from the first clinical isolate). We demonstrate that expression of the OmpC K12 porin in the clinical isolates lowers the MIC, consistent with modified porin function contributing to drug resistance. By a range of assays we have established that the three mutations that occur between OmpC20 and OmpC33 modify transport of both small molecules and antibiotics across the outer membrane. This results in the modulation of resistance to antibiotics, particularly cefotaxime. Small ion unitary conductance measurements of the isolated porins do not show significant differences between isolates. Thus, resistance does not appear to arise from major changes in pore size. Crystal structures of all four OmpC clinical mutants and molecular dynamics simulations also show that the pore size is essentially unchanged. Molecular dynamics simulations suggest that perturbation of the transverse electrostatic field at the constriction zone reduces cefotaxime passage through the pore, consistent with laboratory and clinical data. This subtle modification of the transverse electric field is a very different source of resistance than occlusion of the pore or wholesale destruction of the transverse field and points to a new mechanism by which porins may modulate antibiotic passage through the outer membrane. PMID:22053181

  2. Altered antibiotic transport in OmpC mutants isolated from a series of clinical strains of multi-drug resistant E. coli.

    Directory of Open Access Journals (Sweden)

    Hubing Lou

    Full Text Available Antibiotic-resistant bacteria, particularly gram negative species, present significant health care challenges. The permeation of antibiotics through the outer membrane is largely effected by the porin superfamily, changes in which contribute to antibiotic resistance. A series of antibiotic resistant E. coli isolates were obtained from a patient during serial treatment with various antibiotics. The sequence of OmpC changed at three positions during treatment giving rise to a total of four OmpC variants (denoted OmpC20, OmpC26, OmpC28 and OmpC33, in which OmpC20 was derived from the first clinical isolate. We demonstrate that expression of the OmpC K12 porin in the clinical isolates lowers the MIC, consistent with modified porin function contributing to drug resistance. By a range of assays we have established that the three mutations that occur between OmpC20 and OmpC33 modify transport of both small molecules and antibiotics across the outer membrane. This results in the modulation of resistance to antibiotics, particularly cefotaxime. Small ion unitary conductance measurements of the isolated porins do not show significant differences between isolates. Thus, resistance does not appear to arise from major changes in pore size. Crystal structures of all four OmpC clinical mutants and molecular dynamics simulations also show that the pore size is essentially unchanged. Molecular dynamics simulations suggest that perturbation of the transverse electrostatic field at the constriction zone reduces cefotaxime passage through the pore, consistent with laboratory and clinical data. This subtle modification of the transverse electric field is a very different source of resistance than occlusion of the pore or wholesale destruction of the transverse field and points to a new mechanism by which porins may modulate antibiotic passage through the outer membrane.

  3. 念珠菌类细菌样变异株生物学性状及遗传学特征研究%Study on Biological Characters and Genetic Characteristics of Oidiomycetes Mutant Strains Like Bacterial Morphology

    Institute of Scientific and Technical Information of China (English)

    王华; 苍金荣; 任健康; 苏宝凤; 归巧娣; 张利侠; 刘文康; 闫福堂; 刘英

    2015-01-01

    Objective To investigate the changes of the morphology,structure and biological characters of mutated Candida and through its genetic characteristics,research and reveal the mechanism of the variation at the molecular level.Methods Used different nutritional conditions,different growth conditions and different azole antifungal agents to induce mutation of the standard strains of Candida albicans.In clinical study,Candida mutant strains was isolated from vaginal secretions,pleu-ral effusion and gastric juice samples in patients of poor effect with Antifungal therapy,and studied on the morphological characteristics,and the nuclear structure,the biochemical reaction,the drug resistance,the bacterial composition and the ge-netic characteristics of above variants,etc.Results Mycelial?morphology:Candida were prone to mutation like bacteria, mutant bacteria could show G+ Aureus shape,G+ Bacillus,G+ long filamentous,G- Aureus shape,G- Bacillus and G- long filamentous;Nuclear structure:Candida mutant strains changed like prokaryotes under the electron microscope because it lost the original structure of eukaryotic cells.Biochemical reaction:there were 5 different items in 20 biochemical test ob-served.Drug sensitivity test:Candida mutated to antifungal drugs being originally sensitive was completely resistant,sensi-tive and resistant originally was completely sensitive,and the same as ordinary bacteria resistant.The cell component chan-ges:there was significantly different in Candida variant strain and the atavism of variant strain identified by mass spectrome-try.The most conservative fungalgene expression:Candida mutated had conservative gene expression of eukaryotes.It could be demonstrated that oidiomycetes mutant strains like bacterial morphology with prokaryotic cell biological characteristics was derived from Candida with eukaryotic cells.Conclusion Candida was prone to variation like bacterial morphology.The biological characteristics of mutant resembled prokaryote

  4. The live attenuated Actinobacillus pleuropneumoniae triple-deletion mutant ΔapxIC ΔapxIIC ΔapxIV-ORF1 strain, SLW05, Immunizes pigs against lethal challenge with Haemophilus parasuis.

    Science.gov (United States)

    Fu, Shulin; Ou, Jiwen; Zhang, Minmin; Xu, Juan; Liu, Huazhen; Liu, Jinlin; Yuan, Fangyan; Chen, Huanchun; Bei, Weicheng

    2013-02-01

    Haemophilus parasuis and Actinobacillus pleuropneumoniae both belong to the family Pasteurellaceae and are major respiratory pathogens that cause large economic losses in the pig industry worldwide. We previously constructed an attenuated A. pleuropneumoniae serovar 1 live vaccine prototype, SLW05 (ΔapxIC ΔapxIIC ΔapxIV-ORF1), which is able to produce nontoxic but immunogenic ApxIA, ApxIIA, and ApxIVA. This triple-deletion mutant strain was shown to elicit protective immunity against virulent A. pleuropneumoniae. In the present study, we investigated whether immunization with SLW05 could also protect against lethal challenge with virulent H. parasuis SH0165 (serovar 5) or MD0322 (serovar 4). The SLW05 strain was found to elicit a strong humoral antibody response in pigs and to confer significant protection against challenge with a lethal dose of H. parasuis SH0165 or MD0322. IgG subtype analysis revealed that SLW05 induces a bias toward a Th1-type immune response and stimulates interleukin 2 (IL-2) and gamma interferon (IFN-γ) production. Moreover, antisera from SLW05-vaccinated pigs efficiently inhibited both A. pleuropneumoniae and H. parasuis growth in a whole-blood assay. This is the first report that a live attenuated A. pleuropneumoniae vaccine with SLW05 can protect against lethal H. parasuis infection, which provides a novel approach for developing an attenuated H. parasuis vaccine.

  5. A second function for pseudouridine synthases: A point mutant of RluD unable to form pseudouridines 1911, 1915, and 1917 in Escherichia coli 23S ribosomal RNA restores normal growth to an RluD-minus strain.

    Science.gov (United States)

    Gutgsell, N S; Del Campo, M; Raychaudhuri, S; Ofengand, J

    2001-07-01

    This laboratory previously showed that truncation of the gene for RluD, the Escherichia coli pseudouridine synthase responsible for synthesis of 23S rRNA pseudouridines 1911, 1915, and 1917, blocks pseudouridine formation and inhibits growth. We now show that RluD mutants at the essential aspartate 139 allow these two functions of RluD to be separated. In vitro, RluD with aspartate 139 replaced by threonine or asparagine is completely inactive. In vivo, the growth defect could be completely restored by transformation of an RluD-inactive strain with plasmids carrying genes for RluD with aspartate 139 replaced by threonine or asparagine. Pseudouridine sequencing of the 23S rRNA from these transformed strains demonstrated the lack of these pseudouridines. Pseudoreversion, which has previously been shown to restore growth without pseudouridine formation by mutation at a distant position on the chromosome, was not responsible because transformation with empty vector under identical conditions did not alter the growth rate.

  6. 单核细胞增生性李斯特菌prfA基因缺失株的构建及其生物学特性%Construction and characterization of Listeria monocytogenes ΔprfA mutant strains

    Institute of Scientific and Technical Information of China (English)

    白春光; 殷月兰; 贾艳艳; 付红; 高云飞; 焦新安

    2011-01-01

    [目的]单核细胞增生性李斯特菌(Lm)是人兽共患李斯特菌病的病原菌,其致病性与调控因子PrfA蛋白作用下毒力基因的表达有着密切关系,本文初步探讨了PrfA蛋白对细菌毒力因子的调控作用.[方法]利用同源重组技术对血清型分别为1/2a和4b的LM4、F4636进行prfA基因的敲除,并构建其回复突变株,对获得的突变株LM4ΔprfA、F4636ΔprfA进行生物学特性研究.[结果]实验结果表明:两株缺失株的溶血活性丧失、回复突变株的溶血活性得到恢复,突变株还丧失磷脂酶活性,黏附和侵袭特性显著下降(P<0.05),对BALB/c小鼠的半数致死剂量提高了105个数量级.[结论]由此表明,PrfA蛋白对hly、plcB、inl家族基因的表达及细菌毒力具有重要的调控作用.prfA基因缺失株的构建为进一步研究PrfA蛋白的调控功能提供了材料,为研究其在Lm致病性中的作用奠定了基础.%[Objective] Listeria monocytogenes ( Lm) is an important pathogen that can cause serious listeriosis in humans and animals. The pathogenicity of Lm has a close relationship with the PrfA protein regulating the expression of virulence genes. Therefore, we studied the regulation functions of PrfA and its role on Lm's virulence. [Methods] The prfA genes of LM4, serotype l/2a, and F4636, serotype 4b, were deleted by homologous recombination technology, and the biological characteristics of the mutants were further studied. [ Results ] The prfA gene deleted strains LM4△prfA and F4636△prfA and their back mutation strains were successfully constructed. The results show that the hemolysis activity was lost in prfA deleted strains and was recovered in the reverse mutant strains. The prfA deleted strains lost phospholipase activity; their adhesion and invasion ability significantly decreased. Furthermore, their 50% lethal doses ( LD50) were 5 logs higher comparing with wild type strains. [Conclusion] PrfA regulates hly, plcB and inl gene

  7. Visualization design and verification of Ada tasking using timing diagrams

    Science.gov (United States)

    Vidale, R. F.; Szulewski, P. A.; Weiss, J. B.

    1986-01-01

    The use of timing diagrams is recommended in the design and testing of multi-task Ada programs. By displaying the task states vs. time, timing diagrams can portray the simultaneous threads of data flow and control which characterize tasking programs. This description of the system's dynamic behavior from conception to testing is a necessary adjunct to other graphical techniques, such as structure charts, which essentially give a static view of the system. A series of steps is recommended which incorporates timing diagrams into the design process. Finally, a description is provided of a prototype Ada Execution Analyzer (AEA) which automates the production of timing diagrams from VAX/Ada debugger output.

  8. QUEST/Ada (Query Utility Environment for Software Testing of Ada): The development of a prgram analysis environment for Ada, task 1, phase 2

    Science.gov (United States)

    Brown, David B.

    1990-01-01

    The results of research and development efforts are described for Task one, Phase two of a general project entitled The Development of a Program Analysis Environment for Ada. The scope of this task includes the design and development of a prototype system for testing Ada software modules at the unit level. The system is called Query Utility Environment for Software Testing of Ada (QUEST/Ada). The prototype for condition coverage provides a platform that implements expert system interaction with program testing. The expert system can modify data in the instrument source code in order to achieve coverage goals. Given this initial prototype, it is possible to evaluate the rule base in order to develop improved rules for test case generation. The goals of Phase two are the following: (1) to continue to develop and improve the current user interface to support the other goals of this research effort (i.e., those related to improved testing efficiency and increased code reliable); (2) to develop and empirically evaluate a succession of alternative rule bases for the test case generator such that the expert system achieves coverage in a more efficient manner; and (3) to extend the concepts of the current test environment to address the issues of Ada concurrency.

  9. Ada 9X Project Report, A Study of Implementation-Dependent Pragmas and Attributes in Ada

    Science.gov (United States)

    1989-11-01

    line. The link option files may be entered into the XD ACS library and modified without the need for pro - gram recompilation. The use of ACS option...to the declarative part of a machine code procedure. The pro - gram must make use of the system package MACHINECODE for this purpose. Implicit code is...Appendix F) Rational M1 750a Version 2.0.122 R1000, D 10 9 1 1750a host Mikros MKS 1750/S0, bare machine Validation Summary Report, Appendix B (Ada RM

  10. A report on NASA software engineering and Ada training requirements

    Science.gov (United States)

    Legrand, Sue; Freedman, Glenn B.; Svabek, L.

    1987-01-01

    NASA's software engineering and Ada skill base are assessed and information that may result in new models for software engineering, Ada training plans, and curricula are provided. A quantitative assessment which reflects the requirements for software engineering and Ada training across NASA is provided. A recommended implementation plan including a suggested curriculum with associated duration per course and suggested means of delivery is also provided. The distinction between education and training is made. Although it was directed to focus on NASA's need for the latter, the key relationships to software engineering education are also identified. A rationale and strategy for implementing a life cycle education and training program are detailed in support of improved software engineering practices and the transition to Ada.

  11. Latvian PR people are world class / Ada Parr

    Index Scriptorium Estoniae

    Parr, Ada

    2004-01-01

    Suhtekorraldusfirma Porter Novelli rahvusvahelise partnerluse juht suhtekorralduse osatähtsuse kasvust ettevõtete äritegevuses, suhtekorraldusturu olukorrast ja teenuste kvaliteedi tasemest Baltimaades. Vt. samas: Ada Parr recommends

  12. On some key features of Ada : Language and programming environment

    Science.gov (United States)

    Wehrum, R. P.; Hoyer, W.; Dießl, G.

    1986-08-01

    The present paper focuses upon those aspects of the Ada language whose purpose is to support the discipline of software engineering. It illustrates the use of Ada features for various forms of abstraction, separate compilation, exception handling and tasking and highlights the importance of separating the definition of a module interface from its implementation. It demonstrates the use of the package concept to realize information hiding, data encapsulation and abstract data types. Some key aspects of Ada numerics are dealt with briefly. The paper continues by providing an overview of the Ada programming environments, their history and their relationship to the CAIS interface. Finally, the special importance of the interactive debugger within such an environment is presented.

  13. Latvian PR people are world class / Ada Parr

    Index Scriptorium Estoniae

    Parr, Ada

    2004-01-01

    Suhtekorraldusfirma Porter Novelli rahvusvahelise partnerluse juht suhtekorralduse osatähtsuse kasvust ettevõtete äritegevuses, suhtekorraldusturu olukorrast ja teenuste kvaliteedi tasemest Baltimaades. Vt. samas: Ada Parr recommends

  14. Survey of Ada (Trademark)-Based PDLs (Program Design Language).

    Science.gov (United States)

    1985-01-01

    Jane Stoughton Tel: 602-721-0500 PDL Identification: Byron Organization: Intermetrics, Inc. 733 Concord Avenue Cambridge, MA 02138 Contact: Barbara...827-9519 Organization: BTO Technical Operations 6365 East Tanque Verde Suite 200 Tucson, AZ 85717 PDL Identification: Bell Ada PDL Contact: Mary Jane ...a Related Syntax for an Ada POL," Mayda Software Engineering. iii) Nancy May Linden, "CASPOMAT - an Automated Teller System," and tool input and

  15. Considerations for the design of Ada reusable packages

    Science.gov (United States)

    Nise, Norman S.; Giffin, Chuck

    1986-01-01

    Two important considerations that precede the design of Ada reusable packages (commonality and programming standards) are discuessed. First, the importance of designing packages to yield widespread commonality is expressed. A means of measuring the degree of applicability of packages both within and across applications areas is presented. Design consideration that will improve commonality are also discussed. Second, considerations for the development of programming standards are set forth. These considerations will lead to standards that will improve the reusability of Ada packages.

  16. Evaluation of Ada as a Communications Programming Language.

    Science.gov (United States)

    1981-03-31

    drastically, altered or circumvented to provide a communicatin system with sufficient resources to operate at a required level of performance. 3.3.1.2...Command (CORADCO4) and standard Digital Equipment Corporation VAX 11/780 system * software. Plans include the hosting of Ada/ED on the VAX 11/780 at the... Corporation , Bedford, MA, August, 1978. b. /LOGl79a/ LOGICON, "Formal Specification of GUARD Trusted Software (Draft)," ARPA-78C032303, September, 1979

  17. Las drogas diseñadas

    Directory of Open Access Journals (Sweden)

    Eddie Alvarado Vargas

    1998-12-01

    Full Text Available Cada vez cobra más fuerza la clasificación de las drogas que las divide en psictrópicos y estupefacientes y en Costa Rica se ha añadido la sustancia inhalable. Se hace una ligera definición sobre lo que es una droga y la diferencia con las sustancias indispensables para el organismo como son el agua, el oxígeno y los alimentos las cuales son necesarias para el mismo. En el mundo cada vez es mayor el número de estas sustancias fiscalizadas, y que es considerada una acción delictiva en determinadas ocasiones. Convenios internacionales que deben ser ratificados por las naciones exige que se especifique previamente el objeto material del Delito. Las Drogas Diseñadas son aquellas que por algún cambio realizado en un laboratorio sobre su molécula, tienen los efectos muchas veces superiores a la droga madre, pero que por no estar en la lista de drogas fiscalizadas en el momento de aparición de la misma, va permitiendo que, mientras se agrega a la lista de las mencionadas drogas fiscalizadas, estos actos queden impunes con gran daño por la Salud Pública y del individuo durante mucho tiempo. Costa Rica no escapa de esta realidad por lo que el "narcotraficante" siempre irá adelante con nuevas drogas diseñadas causando grandes estragos, mientras las mismas poco a poco se van incluyendo en la lista de sustancias fiscalizadas. Se hace mención sobre posibles soluciones, entre ellas está incluir en las listas de los convenios internacionales, decretos y reglamentos, nueva terminología que incluya las posibles variaciones de las moléculas de las sustancias fiscalizadas.Every time takes greater force the clasification of drugs, which are divided in psichotropics and stupefacients, and in Costa Rica a new classification has been added: inhalable sustances. A light definition of what a drug is and the difference between the indispensable sustances for the organism like the water, oxigen and food which are necesary for life.Every time the number

  18. Hydraulic Capacity of an ADA Compliant Street Drain Grate

    Energy Technology Data Exchange (ETDEWEB)

    Lottes, Steven A. [Argonne National Lab. (ANL), Argonne, IL (United States); Bojanowski, Cezary [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    Resurfacing of urban roads with concurrent repairs and replacement of sections of curb and sidewalk may require pedestrian ramps that are compliant with the American Disabilities Act (ADA), and when street drains are in close proximity to the walkway, ADA compliant street grates may also be required. The Minnesota Department of Transportation ADA Operations Unit identified a foundry with an available grate that meets ADA requirements. Argonne National Laboratory’s Transportation Research and Analysis Computing Center used full scale three dimensional computational fluid dynamics to determine the performance of the ADA compliant grate and compared it to that of a standard vane grate. Analysis of a parametric set of cases was carried out, including variation in longitudinal, gutter, and cross street slopes and the water spread from the curb. The performance of the grates was characterized by the fraction of the total volume flow approaching the grate from the upstream that was captured by the grate and diverted into the catch basin. The fraction of the total flow entering over the grate from the side and the fraction of flow directly over a grate diverted into the catch basin were also quantities of interest that aid in understanding the differences in performance of the grates. The ADA compliant grate performance lagged that of the vane grate, increasingly so as upstream Reynolds number increased. The major factor leading to the performance difference between the two grates was the fraction of flow directly over the grates that is captured by the grates.

  19. Examining the reliability of ADAS-Cog change scores.

    Science.gov (United States)

    Grochowalski, Joseph H; Liu, Ying; Siedlecki, Karen L

    2016-09-01

    The purpose of this study was to estimate and examine ways to improve the reliability of change scores on the Alzheimer's Disease Assessment Scale, Cognitive Subtest (ADAS-Cog). The sample, provided by the Alzheimer's Disease Neuroimaging Initiative, included individuals with Alzheimer's disease (AD) (n = 153) and individuals with mild cognitive impairment (MCI) (n = 352). All participants were administered the ADAS-Cog at baseline and 1 year, and change scores were calculated as the difference in scores over the 1-year period. Three types of change score reliabilities were estimated using multivariate generalizability. Two methods to increase change score reliability were evaluated: reweighting the subtests of the scale and adding more subtests. Reliability of ADAS-Cog change scores over 1 year was low for both the AD sample (ranging from .53 to .64) and the MCI sample (.39 to .61). Reweighting the change scores from the AD sample improved reliability (.68 to .76), but lengthening provided no useful improvement for either sample. The MCI change scores had low reliability, even with reweighting and adding additional subtests. The ADAS-Cog scores had low reliability for measuring change. Researchers using the ADAS-Cog should estimate and report reliability for their use of the change scores. The ADAS-Cog change scores are not recommended for assessment of meaningful clinical change.

  20. Ada Dual-Use Summary: Ada Dual-Use Workshop Held in Vienna, Virginia on October 19-20, 1993. Ada Dual-Use Committee Briefing, November 8, 1993

    Science.gov (United States)

    1993-11-29

    the maintnance cost with the development cost = I believe Ada will prove more cost -effective. The stndard accoutting practie established by the...1993- Our Current Strategy 7I Build engineered products, high reuse and low support costs . 71 Joint ventures for Ada products o Strategies: Ada...DISA and the Serviccs). 3. Current marketing efforts should be expanded to increase Ada awareness and appeal to commercial firms (Office ot Primary

  1. Remolding Diversified Objects in Ada95: Toward A-Object Pattern

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Ada provides full capacities of supporting object-orientation,but the diversified objects patterned in Ada are so intricate that Ada95's aim would be demolished. In order to complement the disfigurement that Ada does lack for a pr istine notion of class, this paper presents a remolded object pattern known as A -object, an Ada-based class description language A-ObjAda aiming at support f or A-object pattern and the related approach for key algorithms and implementation . In consequent, A-ObjAda hereby promotes Ada with highlighted object-orientati on , which not only effectively exploits the capacities in Ada95, but also rational ly hides befuddling concepts from Ada95.

  2. AdaNET phase 0 support for the AdaNET Dynamic Software Inventory (DSI) management system prototype. Catalog of available reusable software components

    Science.gov (United States)

    Hanley, Lionel

    1989-01-01

    The Ada Software Repository is a public-domain collection of Ada software and information. The Ada Software Repository is one of several repositories located on the SIMTEL20 Defense Data Network host computer at White Sands Missile Range, and available to any host computer on the network since 26 November 1984. This repository provides a free source for Ada programs and information. The Ada Software Repository is divided into several subdirectories. These directories are organized by topic, and their names and a brief overview of their topics are contained. The Ada Software Repository on SIMTEL20 serves two basic roles: to promote the exchange and use (reusability) of Ada programs and tools (including components) and to promote Ada education.

  3. ADA1 and NET1 Genes of Yeast Mediate Both Chromosome Maintenance and Mitochondrial $\\rho^{-}$ Mutagenesis

    CERN Document Server

    Koltovaya, N A; Tchekhouta, I A; Devin, A B

    2002-01-01

    An increase in the mitochondrial (mt) rho^- mutagenesis is a well-known respose of yeast cells to mutations in the numerous nuclear genes as well as to various kinds of stress. Notwithstanding the extensive studies during several decades the biological significance of this response is not yet fully understood. The genetic approach to solution of this subject includes the study of genes that are required for the high incidence of spontaneous rho^- mutants. Previously we found that mutations in certain nuclear genes including CDC28, the central cell-cycle regulation gene, may decrease the spontaneous rho^- mutability and simultaneously affect maintenance of the yeast chromosomes and plasmids. The present work provides data on identification of two more genes, resembling CDC28 in this respect. These genes NET1 and ADA1 mediate important regulatory protein-protein interactions in the yeast cell. The effects of net1 and ada1 mutations on the maintenance of yeast mt genome, chromosomes and plasmids as well as on ce...

  4. TO ESTIMATE SERUM ADA LEVELS IN BCG VACCINATED CHILDREN

    Directory of Open Access Journals (Sweden)

    Manjunatha Babu

    2015-04-01

    Full Text Available BACKGROUND: Tuberculosis is an important cause of morbidity and mortality in both adults and children, especially in developing countries. For prevention of childhood tuberculosis, BCG vaccination is advocated. Protection is attained 4 - 6 weeks after BCG vaccination a nd is mainly due to cell mediated immunity. After BCG vaccination almost 12 to 15% of neonates do not develop scar but have positive cell mediated immune response. ADA estimation is simple and inexpensive method to assess the cell mediated immunity. OBJECT IVE: To estimate serum ADA levels in children with and without BCG scar, after receiving BCG vaccination. MATERIAL AND METHODS: This prospective observational study was conducted at a tertiary care hospital for a period of 2 years. Babies in post natal ward and infants up to the age of 12 weeks attending well baby clinic for BCG vaccination were included in the study. Serum ADA lev els were estimated before BCG vaccination and 12 - 14 weeks after the vaccination. ADA levels were estimated by colorimetric method. Presence or absence of BCG scar was noted at 12 - 14 weeks of age. RESULTS: A total of 75 babies followed up, of which only 60 babies noted to have scar and in rest 15 babies there was no scar noticed. Twenty unvaccinated babies at 12 weeks of age were included as controls. The Mean ADA levels are significantly elevated after BCG vaccination (34 . 12 ± 3 . 28 U/L in comparison to le vels before vaccination (12 . 55± 2 . 64 U/L with p value 0. 06. CONCLUSION: After BCG vaccination, there is increase in serum ADA levels indicating adequ ate immunity. Increase in ADA levels in children without scar after BCG vaccination may indicate the probability of adequate immunity.

  5. Construction and characterization of double mutant strain hif-1(ia04);glb-13(tm2825)in C.elegans%秀丽隐杆线虫双突变株系hif-1(ia04);glb-13(tm2825)的制备与鉴定

    Institute of Scientific and Technical Information of China (English)

    石锦平; 任长虹; 李媛; 张成岗

    2011-01-01

    Objective To investigate the physiological function of the glb-13 gene, to backcross glb-13 (tm2825) and to construct double mutant strain hif-1 (ia04) ;g lb-13 (tm2825) in Caenorhabditis elegans. Methods The glb-13 (tm2825) mutant male strain was obtained by mating the glb-13 (tm2825) mutant hermaphrodite with the male N2 strain, and then with the N2 hermaphrodite. It was then backcrossed twice, and the homozygote was identified by single C. elegans genome PCR. The male hif-1(ia04) mutant strain, which was obtained by mating the hif-l(ia04) mutant hermaphrodite with wildtype N2 strain, was further mated with the glb-13(tm2825) mutant hermaphrodite. The homozygote was also identified by single C. elegans genome PCR. Results The backcrossed mutant strain glb-13 ( tm2825 ) and the homozygotes hif-1 ( ia04 ) ;glb-13(tm2825) double mutant were obtained. Conclusion Backcross can maintain the mutant's genetic stability while mutant mating can construct a double mutant. This finding will facilitate further functional studies of the glb-13 gene.%目的 以秀丽隐杆线虫为模式生物研究珠蛋白(globin)13(lgb-13)的生理作用,以回交2次的glb-13(tm2825)突变株系和hif-1(ia04)构建线虫双突变株系hif-1(ia04);glb-13(tm2825).方法 glb-13(tm2825)与野生型N2株系交配获得glb-13(tm2825)的雄虫,再与N2的雌雄同体线虫进行交配,回交2次后,通过单只线虫基因组PCR法鉴定出交配后的纯合体.使用hif-1(ia04)和野生型线虫N2进行交配得到hif-1(ia04)的雄虫,然后再与glb-13(tm2825)雌雄同体线虫交配,通过单只线虫基因组PCR法鉴定出交配后的纯合体.结果 获得hif-1(ia04);glb-13(tm2S25)双突变株系.结论 通过线虫交配回交可以使突变株系线虫保持稳定性状,而突变株系之间的交配可以制备出双突变株系,为深入开展glb-13的功能研究奠定了物质基础.

  6. Methods of producing protoporphyrin IX and bacterial mutants therefor

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jizhong; Qiu, Dongru; He, Zhili; Xie, Ming

    2016-03-01

    The presently disclosed inventive concepts are directed in certain embodiments to a method of producing protoporphyrin IX by (1) cultivating a strain of Shewanella bacteria in a culture medium under conditions suitable for growth thereof, and (2) recovering the protoporphyrin IX from the culture medium. The strain of Shewanella bacteria comprises at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX. In certain embodiments of the method, the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or of shew_1140. In other embodiments, the presently disclosed inventive concepts are directed to mutant strains of Shewanella bacteria having at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX during cultivation of the bacteria. In certain embodiments the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or shew_1140.

  7. Analysis of Generalization Ability for Different AdaBoost Variants Based on Classification and Regression Trees

    Directory of Open Access Journals (Sweden)

    Shuqiong Wu

    2015-01-01

    Full Text Available As a machine learning method, AdaBoost is widely applied to data classification and object detection because of its robustness and efficiency. AdaBoost constructs a global and optimal combination of weak classifiers based on a sample reweighting. It is known that this kind of combination improves the classification performance tremendously. As the popularity of AdaBoost increases, many variants have been proposed to improve the performance of AdaBoost. Then, a lot of comparison and review studies for AdaBoost variants have also been published. Some researchers compared different AdaBoost variants by experiments in their own fields, and others reviewed various AdaBoost variants by basically introducing these algorithms. However, there is a lack of mathematical analysis of the generalization abilities for different AdaBoost variants. In this paper, we analyze the generalization abilities of six AdaBoost variants in terms of classification margins. The six compared variants are Real AdaBoost, Gentle AdaBoost, Modest AdaBoost, Parameterized AdaBoost, Margin-pruning Boost, and Penalized AdaBoost. Finally, we use experiments to verify our analyses.

  8. An automated quality assessor for Ada object-oriented designs

    Science.gov (United States)

    Bailin, Sidney C.

    1988-01-01

    A tool for evaluating object-oriented designs (OODs) for Ada software is described. The tool assumes a design expressed as a hierarchy of object diagrams. A design of this type identifies the objects of a system, an interface to each object, and the usage relationships between objects. When such a design is implemented in Ada, objects become packages, interfaces become package specifications, and usage relationships become Ada `with' clauses and package references. An automated quality assessor has been developed that is based on flagging undesirable design constructs. For convenience, distinctions are made among three levels of severity: questionable, undesirable, and hazardous. A questionable construct is one that may well be appropriate. An undesirable construct is one that should be changed because it is potentially harmful to the reliability, maintainability, or reusability of the software. A hazardous construct is one that is undesirable and that introduces a high level of risk.

  9. [Improving ethanol tolerance of Saccharomyces cerevisiae industrial strain by directed evolution of SPT3].

    Science.gov (United States)

    Zhao, Xinqing; Jiang, Rujiao; Li, Ning; Yang, Qing; Bai, Fengwu

    2010-02-01

    Directed evolution of transcription factors can be employed to effectively improve the phenotypes which are controlled by multiple genetic loci. In this study, we used error-prone PCR for the directed evolution of SPT3, which is the component of yeast Spt-Ada-Gcn5-acetyltransferase (SAGA) complex responsible for the transcription of stress-related genes, and studied its effect on the improvement of ethanol tolerance. Mutant library was constructed by ligating the error-prone PCR products with a modified pYES2.0 plasmid, and the expression plasmids were subsequently transformed to yeast industrial strain Saccharomyces cerevisiae 4126. One mutant strain M25 showing superior growth in presence of 10% ethanol was selected. M25 produced 11.7% more ethanol than the control strain harboring the empty vector when 125 g/L glucose was used as substrate. This study revealed that SPT3 is an important transcription factor for the metabolic engineering of yeast ethanol tolerance.

  10. An Ada run-time control architecture for telerobots

    Science.gov (United States)

    Balaram, J.; Rodriguez, G.

    1987-01-01

    This paper describes the architecture and Ada language implementation of a process-level run-time control subystem for the Jet Propulsion Laboratory (JPL) telerobot system. The concept of run-time control in a combined robot-teleoperation environment is examined and the telerobot system at JPL is described. An Ada language implementation of the JPL Telerobot Run-Time Controller (RTC) is described by highlighting the functional behavior of the subsystem, defining the internal modules, and providing a functional flow time sequence of internal module activity.

  11. The development of an Ada programming support environment database: SEAD (Software Engineering and Ada Database), user's manual

    Science.gov (United States)

    Liaw, Morris; Evesson, Donna

    1988-01-01

    This is a manual for users of the Software Engineering and Ada Database (SEAD). SEAD was developed to provide an information resource to NASA and NASA contractors with respect to Ada-based resources and activities that are available or underway either in NASA or elsewhere in the worldwide Ada community. The sharing of such information will reduce the duplication of effort while improving quality in the development of future software systems. The manual describes the organization of the data in SEAD, the user interface from logging in to logging out, and concludes with a ten chapter tutorial on how to use the information in SEAD. Two appendices provide quick reference for logging into SEAD and using the keyboard of an IBM 3270 or VT100 computer terminal.

  12. Construction and characterization of the cAMP receptor protein gene deletion mutant of Salmonella typhimurium SL1344 strain%鼠伤寒沙门菌SL1344株cAMP受体蛋白基因缺失株的构建及其生物学特性

    Institute of Scientific and Technical Information of China (English)

    廖成水; 程相朝; 赵战勤; 张春杰; 李银聚; 吴庭才; 郁川; 王晓利; 胡阿勇

    2011-01-01

    The cAMP receptor protein gene(crp) deletion mutant of Salmonella typhimurium SL1344 strain was constructed by the allelic exchange introduced by the transduction of suicide plasmid.In addition,the biological characteristics of the mutant were determined.Firstly,the upstream and downstream fragments of crp gene were amplified from SL1344 strain genome.The two fragments were successively cloned into the suicide pRE112 vector to construct the recombinant suicide vector pREΔcrp harboring the 321 bp-deleted crp fragment.The recombination suicide vector was conjugated with SL1344 and the unmarked crp deleted strain without resistance was selected by two-step method and crp deletion on the genome was determined by PCR.The serotype of the mutant was 1,4,5,12:i:1,2,identical to the parent SL1344.The mutant was stable with the recombinant Δcrp gene in vitro.However,the carbohydrate fermentation or utilization assays of the mutant were differed from the parent SL1344 strain,obviously.The growth velocity of the mutant was more slowly compared with SL1344.The chicken lethal test showed that the virulence of the SL1344 Δcrp mutant strain with LD50 of 7.40×109 CFU was 32 456 times lower than the parent SL1344 strain with LD50 of 2.28×105 CFU.These results showed that the SL1344 Δcrp mutant was constructed successfully.It is likely that this Δcrp mutant could be adapted to develop attenuated Salmonella vaccine.%通过自杀性质粒介导的细菌同源重组技术,构建鼠伤寒沙门菌SL1344株的crp基因缺失疫苗候选菌株,并对其生物学特性进行初步研究。首先构建含缺失321bp crp基因的重组自杀性质粒pREΔcrp,然后利用重组自杀性质粒介导的等位基因交换技术,两步法筛选SL1344的Δcrp缺失株,用PCR鉴定结果表明该缺失株构建成功。生物学特性研究发现,缺失株ΔcrpSL1344保留了亲本菌株SL1344的血清型1,4,5,12:i:1,2,且能够稳定遗传缺失321bp的crp

  13. AdaBoost分类算法的数学分析%The Mathematical Analysis of AdaBoost Algorithm

    Institute of Scientific and Technical Information of China (English)

    王兵

    2014-01-01

    This article provides a gentle introduction to the AdaBoost algorithm, and the mathematical analysis of how to draft classifiers and assign a weight for them, finally form a strong classifier through a set of weak classifiers.%本文对AdaBoost算法进行了介绍,并从整个数学推导过程中分析怎样挑选分类器并设置权值,最终通过一组弱分类器组合构成强分类器。

  14. Behavioral characterization of system xc- mutant mice.

    Science.gov (United States)

    McCullagh, Elizabeth A; Featherstone, David E

    2014-05-15

    The slc7a11 gene encodes xCT, an essential component of 'system xc-', a plasma membrane exchanger that imports cystine and exports glutamate. Slc7a11 is expressed primarily in the brain, but its role there is not clear. We performed behavioral tests on two different strains of homozygous slc7a11 mutant mice ('sut' and 'xCT'), as well as heteroallelic offspring of these two strains ('xCT/sut') and their associated genetic backgrounds. Homozygous sut mutant males showed reduced spontaneous alternation in spontaneous alternation tasks as well as reduced movement in an open field maze, but xCT and xCT/sut strains did not show significant changes in these tasks compared to appropriate controls. Neither xCT nor sut mutants showed differences from controls in rotarod tests. Female behavioral phenotypes were independent of estrus cycle stage. To ensure that homozygous xCT, sut, and xCT/sut strains all represent protein null alleles, we measured whole brain xCT protein levels using immunoblots. xCT, sut and xCT/sut strains showed no detectable xCT protein expression, confirming them as null alleles. Previously published microdialysis experiments showed reduced striatal glutamate in xCT mutants. Using the same methods, we measured reduced interstitial glutamate levels in the striatum but not cerebellum of sut mutants. However, we detected no glutamate change in the striatum or cerebellum of sut/xCT mice. We detected no changes in whole brain EAAT-1, -2, or -3 expression. We conclude that the behavioral and chemical differences exist between slc7a11 mutant strains, but we were unable to definitively attribute any of these differences to loss of system xc-.

  15. The Rate of Convergence of AdaBoost

    CERN Document Server

    Mukherjee, Indraneel; Schapire, Robert E

    2011-01-01

    The AdaBoost algorithm was designed to combine many "weak" hypotheses that perform slightly better than random guessing into a "strong" hypothesis that has very low error. We study the rate at which AdaBoost iteratively converges to the minimum of the "exponential loss." Unlike previous work, our proofs do not require a weak-learning assumption, nor do they require that minimizers of the exponential loss are finite. Our first result shows that at iteration $t$, the exponential loss of AdaBoost's computed parameter vector will be at most $\\epsilon$ more than that of any parameter vector of $\\ell_1$-norm bounded by $B$ in a number of rounds that is at most a polynomial in $B$ and $1/\\epsilon$. We also provide lower bounds showing that a polynomial dependence on these parameters is necessary. Our second result is that within $C/\\epsilon$ iterations, AdaBoost achieves a value of the exponential loss that is at most $\\epsilon$ more than the best possible value, where $C$ depends on the dataset. We show that this d...

  16. Preliminary Design of the Ada Programming Support Environment Configuration Manager.

    Science.gov (United States)

    1984-06-01

    October 1980. 62 ............................................... 10. Buxton , J. and V. H. Stenning, eds. "Stoneman," Requirements for Ada Programming...18. Stoner, Bill . Logicon. Course EE 5.45, "Software Acquisition," School of Engineering, Air Force Institute of Technology, Wright-Patterson AFB OH

  17. ADA and multi-microprocessor real-time simulation

    Science.gov (United States)

    Feyock, S.; Collins, W. R.

    1983-01-01

    The selection of a high-order programming language for a real-time distributed network simulation is described. The additional problem of implementing a language on a possibly changing network is addressed. The recently designed language ADA (trademarked by DoD) was chosen since it provides the best model of the underlying application to be simulated.

  18. 77 FR 36231 - Americans With Disabilities Act (ADA) and Architectural Barriers Act (ABA) Accessibility...

    Science.gov (United States)

    2012-06-18

    ... Architectural Barriers Act (ABA) Accessibility Guidelines; Emergency Transportable Housing Units AGENCY... Disabilities Act (ADA) and Architectural Barriers Act (ABA) Accessibility Guidelines to specifically address... the ADA or ABA are readily accessible to and usable by individuals with disabilities. Other...

  19. CSF ADENOSINE DEAMINASE (ADA ACTIVITY IN PATIENTS WITH MENINGITIS

    Directory of Open Access Journals (Sweden)

    Justin

    2016-05-01

    Full Text Available Meningitis is inflammation of the meninges (pia, arachnoid and dura mater covering the brain and the spinal cord. ADA is an enzyme in the purine salvage pathway which is found in abundance in active T-lymphocytes. Hence, an attempt was made to estimate the CSF ADA level in patients with suspected meningitis and throw light on its use in differentiating the various types of meningitis. AIMS AND OBJECTIVES To estimate the level of CSF adenosine deaminase level in different types of meningitis. To assess its usefulness in differentiating the various types (bacterial, viral and tuberculous of meningitis. MATERIALS AND METHODS The study was conducted at the medical wards of Govt. Rajaji Hospital, Madurai, a prospective analytical study from a period of April 2012 to September 2012. OBSERVATION AND RESULTS Tuberculous meningitis occurred more in the age group of 21–40 years. Bacterial meningitis was seen mainly in patients < 20 years of age. Viral meningitis was seen in all age groups. CSF ADA level was highest in tuberculous meningitis, the mean value being 24.5 U/L. The mean value of ADA in bacterial meningitis was 4.54 U/L and viral meningitis patients had lowest mean ADA value of 2.65 U/L. CONCLUSION In our study, 50 patients with meningitis admitted in Government Rajaji Hospital from April 2012 to September 2012 were evaluated. Meningitis predominantly affected people in the age group of 20-40 years in our study with a male: female ratio of 1.9:1. Cases of tuberculous meningitis constituted 48% of the study group and bacterial and viral meningitis were 26% each. CSF protein values were higher and sugar values lower in patients with tuberculous and bacterial meningitis. CSF cell counts were higher in patients with bacterial meningitis.

  20. Characterization of a Salmonella typhimurium mutant defective in phosphoribosylpyrophosphate synthetase

    DEFF Research Database (Denmark)

    Jochimsen, Bjarne; Hove-Jensen, Bjarne; Garber, Bruce B.;

    1985-01-01

    This study describes the isolation and characterization of a mutant (strain GP122) of Salmonella typhimurium with a partial deficiency of phosphoribosylpyrophosphate (PRPP) synthetase activity. This strain was isolated in a purE deoD gpt purine auxotroph by a procedure designed to select guanosine......-utilizing mutants. Strain GP122 had roughly 15% of the PRPP synthetase activity and 25% of the PRPP pool of its parent strain. The mutant exhibited many of the predicted consequences of a decreased PRPP pool and a defective PRPP synthetase enzyme, including: poor growth on purine bases; decreased accumulation of 5...... phosphoribosyltransferase, enzymes involved in the pyrimidine de novo biosynthetic pathway; growth stimulation by PRPP-sparing compounds (e.g. guanosine, histidine); poor growth in low phosphate medium; and increased heat lability of the defective enzyme. This mutant strain also had increased levels of guanosine 5...

  1. Selection and characterization of L-ethionine resistant mutants of Trichosporon cutaneum.

    Science.gov (United States)

    Georgieva, Nelly; Alexieva, Zlatka

    2005-01-01

    Trichosporon cutaneum R57 and its L-ethionine resistant mutant NZ94 strain were investigated. The amino acid analyses of cell content of both strains were carried out. The pool of free methionine in the mutant strain is enhanced 16.5 times. The total amount of sulphur-containing amino acids in the mutant cells was significantly increased from 36.8 in the wild strain to 113.4 mg/g protein in the mutant strain. In the process of mutant strain cultivation there was found a high excretion of free methionine (259 microg/ml) in the medium. It was shown that the amino acid content of both wild and mutant strains would be helpful for formulating of new improved animal nutritional diets.

  2. A Pre-Allocation Strategy for Implement ADA95's Distrbuted Computing

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to realize distributed computing of Ada95, this paper discusses Ada95's distributed system model and an implement model of Ada95's distributed computing—workstation cluster model. Under this model, we presents a pre-allocation strategy for allocating the computation quantity of distributed units evenly among workstations and also reducing the communication expense between those distributed units.

  3. ELAPSE - NASA AMES LISP AND ADA BENCHMARK SUITE: EFFICIENCY OF LISP AND ADA PROCESSING - A SYSTEM EVALUATION

    Science.gov (United States)

    Davis, G. J.

    1994-01-01

    One area of research of the Information Sciences Division at NASA Ames Research Center is devoted to the analysis and enhancement of processors and advanced computer architectures, specifically in support of automation and robotic systems. To compare systems' abilities to efficiently process Lisp and Ada, scientists at Ames Research Center have developed a suite of non-parallel benchmarks called ELAPSE. The benchmark suite was designed to test a single computer's efficiency as well as alternate machine comparisons on Lisp, and/or Ada languages. ELAPSE tests the efficiency with which a machine can execute the various routines in each environment. The sample routines are based on numeric and symbolic manipulations and include two-dimensional fast Fourier transformations, Cholesky decomposition and substitution, Gaussian elimination, high-level data processing, and symbol-list references. Also included is a routine based on a Bayesian classification program sorting data into optimized groups. The ELAPSE benchmarks are available for any computer with a validated Ada compiler and/or Common Lisp system. Of the 18 routines that comprise ELAPSE, provided within this package are 14 developed or translated at Ames. The others are readily available through literature. The benchmark that requires the most memory is CHOLESKY.ADA. Under VAX/VMS, CHOLESKY.ADA requires 760K of main memory. ELAPSE is available on either two 5.25 inch 360K MS-DOS format diskettes (standard distribution) or a 9-track 1600 BPI ASCII CARD IMAGE format magnetic tape. The contents of the diskettes are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. The ELAPSE benchmarks were written in 1990. VAX and VMS are trademarks of Digital Equipment Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

  4. Ada Compiler Validation Summary Report: Certificate Number: 901112W1. 11116 Cray Research, Inc., Cray Ada Compiler, Release 2.0, Cray X-MP/EA (Host & Target)

    Science.gov (United States)

    1990-11-12

    9. Summary of parameter types 140 Interlanguage data access for Ada calling C 152 Table 10. Summary of parameter types 141 Pragma INTERFACZ for for... interlanguage programming. The conventions described in this manual apply only to software running on Cray Research systems. You can find descriptions of...these conventions in Interlanguage Programming Conventions, publication SN-3009. Ada also supports callback. A foreign routine can call an Ada routine by

  5. AdaBoost for Improved Voice-Band Signal Classification

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A good voice-band signal classification can not only enable the safe application of speech coding techniques,the implementation of a Digital Signal Interpolation (DSI)system, but also facilitate network administration and planning by providing accurate voice-band traffic analysis.A new method is proposed to detect and classify the presence of various voice-band signals on the General Switched Telephone Network ( GSTN ). The method uses a combination of simple base classifiers through the AdaBoost algorithm. The conventional classification features for voiceband data classification are combined and optimized by the AdaBoost algorithm and spectral subtraction method.Experiments show the simpleness, effectiveness, efficiency and flexibility of the method.

  6. AN ADA LINEAR ALGEBRA PACKAGE MODELED AFTER HAL/S

    Science.gov (United States)

    Klumpp, A. R.

    1994-01-01

    This package extends the Ada programming language to include linear algebra capabilities similar to those of the HAL/S programming language. The package is designed for avionics applications such as Space Station flight software. In addition to the HAL/S built-in functions, the package incorporates the quaternion functions used in the Shuttle and Galileo projects, and routines from LINPAK that solve systems of equations involving general square matrices. Language conventions in this package follow those of HAL/S to the maximum extent practical and minimize the effort required for writing new avionics software and translating existent software into Ada. Valid numeric types in this package include scalar, vector, matrix, and quaternion declarations. (Quaternions are fourcomponent vectors used in representing motion between two coordinate frames). Single precision and double precision floating point arithmetic is available in addition to the standard double precision integer manipulation. Infix operators are used instead of function calls to define dot products, cross products, quaternion products, and mixed scalar-vector, scalar-matrix, and vector-matrix products. The package contains two generic programs: one for floating point, and one for integer. The actual component type is passed as a formal parameter to the generic linear algebra package. The procedures for solving systems of linear equations defined by general matrices include GEFA, GECO, GESL, and GIDI. The HAL/S functions include ABVAL, UNIT, TRACE, DET, INVERSE, TRANSPOSE, GET, PUT, FETCH, PLACE, and IDENTITY. This package is written in Ada (Version 1.2) for batch execution and is machine independent. The linear algebra software depends on nothing outside the Ada language except for a call to a square root function for floating point scalars (such as SQRT in the DEC VAX MATHLIB library). This program was developed in 1989, and is a copyrighted work with all copyright vested in NASA.

  7. Extracting Objects from Ada83 Programs: A Case Study

    Institute of Scientific and Technical Information of China (English)

    XU Baowen; ZHOU Yuming

    2001-01-01

    Reengineering legacy systems written in conventional procedural languages to equivalent OO systems makes software more maintainable and reliable. This paper proposes a method for extracting objects from legacy Ada83 systems using module features. First, metrics are developed to measure module cohesion. Then, effects on cohesion from changing module components are analyzed and rules about how to extract inheritance relations among objects are given. At the end of this paper, an object-extracting algorithm using module features is proposed.

  8. The INTEL 432/670 and ADA Performance Benchmarks.

    Science.gov (United States)

    1982-12-01

    a QUICK.MSE"); with text4-io,imtio~guicksort; use texto -io,intio,quicksort; package body OUICKSORT is procedure SORT(1eft~ri(3ht : in subimt; arg...time and ’fuss’, A knowledge of ADA is assumed, as is familiarity with VMS (e.g. the VMS editor ), Referring back to Figure(63 it can be seen that a

  9. Olimpíadas e geopolítica

    Directory of Open Access Journals (Sweden)

    João Fábio Bertonha

    2008-09-01

    Full Text Available

    o artigo trata de competições esportivas,

    em especial as olimpíadas. Nelas, valorizam-se o

    nacionalismo e o poder dos países.

  10. AN ADA LINEAR ALGEBRA PACKAGE MODELED AFTER HAL/S

    Science.gov (United States)

    Klumpp, A. R.

    1994-01-01

    This package extends the Ada programming language to include linear algebra capabilities similar to those of the HAL/S programming language. The package is designed for avionics applications such as Space Station flight software. In addition to the HAL/S built-in functions, the package incorporates the quaternion functions used in the Shuttle and Galileo projects, and routines from LINPAK that solve systems of equations involving general square matrices. Language conventions in this package follow those of HAL/S to the maximum extent practical and minimize the effort required for writing new avionics software and translating existent software into Ada. Valid numeric types in this package include scalar, vector, matrix, and quaternion declarations. (Quaternions are fourcomponent vectors used in representing motion between two coordinate frames). Single precision and double precision floating point arithmetic is available in addition to the standard double precision integer manipulation. Infix operators are used instead of function calls to define dot products, cross products, quaternion products, and mixed scalar-vector, scalar-matrix, and vector-matrix products. The package contains two generic programs: one for floating point, and one for integer. The actual component type is passed as a formal parameter to the generic linear algebra package. The procedures for solving systems of linear equations defined by general matrices include GEFA, GECO, GESL, and GIDI. The HAL/S functions include ABVAL, UNIT, TRACE, DET, INVERSE, TRANSPOSE, GET, PUT, FETCH, PLACE, and IDENTITY. This package is written in Ada (Version 1.2) for batch execution and is machine independent. The linear algebra software depends on nothing outside the Ada language except for a call to a square root function for floating point scalars (such as SQRT in the DEC VAX MATHLIB library). This program was developed in 1989, and is a copyrighted work with all copyright vested in NASA.

  11. Overfitting Reduction of Text Classification Based on AdaBELM

    Directory of Open Access Journals (Sweden)

    Xiaoyue Feng

    2017-07-01

    Full Text Available Overfitting is an important problem in machine learning. Several algorithms, such as the extreme learning machine (ELM, suffer from this issue when facing high-dimensional sparse data, e.g., in text classification. One common issue is that the extent of overfitting is not well quantified. In this paper, we propose a quantitative measure of overfitting referred to as the rate of overfitting (RO and a novel model, named AdaBELM, to reduce the overfitting. With RO, the overfitting problem can be quantitatively measured and identified. The newly proposed model can achieve high performance on multi-class text classification. To evaluate the generalizability of the new model, we designed experiments based on three datasets, i.e., the 20 Newsgroups, Reuters-21578, and BioMed corpora, which represent balanced, unbalanced, and real application data, respectively. Experiment results demonstrate that AdaBELM can reduce overfitting and outperform classical ELM, decision tree, random forests, and AdaBoost on all three text-classification datasets; for example, it can achieve 62.2% higher accuracy than ELM. Therefore, the proposed model has a good generalizability.

  12. Software tools to aid Pascal and Ada program design

    Energy Technology Data Exchange (ETDEWEB)

    Jankowitz, H.T.

    1987-01-01

    This thesis describes a software tool which analyses the style and structure of Pascal and Ada programs by ensuring that some minimum design requirements are fulfilled. The tool is used in much the same way as a compiler is used to teach students the syntax of a language, only in this case issues related to the design and structure of the program are of paramount importance. The tool operates by analyzing the design and structure of a syntactically correct program, automatically generating a report detailing changes that need to be made in order to ensure that the program is structurally sound. The author discusses how the model gradually evolved from a plagiarism detection system which extracted several measurable characteristics in a program to a model that analyzed the style of Pascal programs. In order to incorporate more-sophistical concepts like data abstraction, information hiding and data protection, this model was then extended to analyze the composition of Ada programs. The Ada model takes full advantage of facilities offered in the language and by using this tool the standard and quality of written programs is raised whilst the fundamental principles of program design are grasped through a process of self-tuition.

  13. Characterization of Glutamine-Requiring Mutants of Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Joosten, Han M.L.J.; Herst, Patricia M.; Drift, Chris van der

    1982-01-01

    Revertants were isolated from a glutamine-requiring mutant of Pseudomonas aeruginosa PAO. One strain showed thermosensitive glutamine requirement and formed thermolabile glutamine synthetase, suggesting the presence of a mutation in the structural gene for glutamine synthetase. The mutation conferri

  14. Study on culturing Trichodema mutants

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-ai; WANG Wei-ming

    2004-01-01

    @@ Trichodema mutants strains T5, T0803, T1010, T1003were cultured in different conditions and media, also in the presence of fungicides at 40 mg/kg (CK or procymidone + chlorothalonil, or maneb or phosethyl-Al) . The pH values of media were 5, 6, 7 and 8 and hyphae were grown at temperatures of 15, 20, 25 and 30 ℃. After being cultured for 3, 4, 5, or 6 days, the strains were transferred at a lower temperature to sporulate (20℃) Obtained data were analyzed statistically, with the orthogonal array and ranges (R) differing dependes on the treatments (R = 40.0,42.4, 48.0, 62.8,107.0). The results indicated that the most important factor was the nature of the strain (R =107.0), while the change in temperature and time of cultivation produced the lowest effect (R =40.0). Each factor variance was significant and A3B4C2D1E3 was the optimum combined condition, in which strain T1010 grew more quickly and sporulated most.

  15. Comparison of the X-gal- and P-gal-based systems for screening of mutant λlacZ phages originating from the transgenic mouse strain 40.6

    NARCIS (Netherlands)

    Mientjes, E.J.; Steenwinkel, M.J.S.T.; Delft, J.H.M. van; Lohman, P.H.M.; Baan, R.A.

    1996-01-01

    The recent introduction of the phenyl-β-D-galactopyranoside (P-gal)-based positive-selection system for screening of λlacZ phages originating from the λlacZ transgenic mouse (Muta Mouse) has made the determination of mutant frequencies (MF) a much simpler task. Previously, MF data from these mice ha

  16. Repair effects of laser on mutants of filamentous fungi

    Science.gov (United States)

    Zhao, Yansheng; Xiao, Canpeng; Qian, Hailun; Su, Baoliang; Hu, Yujun; Deng, Jianhui

    1999-09-01

    The paper reports that penicillin-producing strains and lovastatin-producing strains were irradiated by UV and subsequently by laser (632.8 nm), and the reparation rate reached 297% and 264%. High-yield mutant was selected with improved potency of 24.5% and 30%, respectively; Gibberellin producing strains were treated with chemical agent LiCl, and then irradiated with 632.8 nm laser. One mutant with 189.6% increased potency was obtained. The experimental results indicated that using laser irradiation after UV or chemical agent mutation was a new useful method in breeding high-yield strains.

  17. Characterization of an adenosine deaminase-deficient human histiocytic lymphoma cell line (DHL-9) and selection of mutants deficient in adenosir kinase and deoxycytidine kinase.

    Science.gov (United States)

    Kubota, M; Kamatani, N; Daddona, P E; Carson, D A

    1983-06-01

    The association of adenosine deaminase (ADA) deficiency with immunodeficiency disease has emphasized the importance of this purine metabolic enzyme for human lymphocyte growth and function. This report describes the natural occurrence of ADA deficiency in a human histiocytic lymphoma cell line, DHL-9. The minimal ADA activity in DHL-9 extracts, 0.028 nmol/min/mg protein, was less than 50% of the activity in two B-lymphoblastoid cell lines from ADA-deficient patients and was resistant to the potent ADA inhibitor deoxycoformycin. A sensitive radioimmunoassay failed to detect immunoreactive ADA in DHL-9 cells. Moreover, in DHL-9 cells, deoxycoformycin did not augment either the growth-inhibitory effects of adenosine and deoxyadenosine or the accumulation of deoxyadenosine triphosphate from deoxyadenosine. When compared to six other human hematopoietic cell lines, DHL-9 had 5.6-fold-higher levels of adenosylhomocysteinase. Chromosome 20, which bears the structural gene for ADA and adenosylhomocysteinase, was diploid and had a normal Giemsa banding pattern. The parental DHL-9 cell line was used for the selection and cloning of secondary mutants deficient in deoxycytidine kinase and adenosine kinase.

  18. Ada/X Window System Bindings: Conversion Strategies

    Science.gov (United States)

    1993-03-18

    6, Tis mtd wrs well on ons of-any creates a label on the system’s startup form. size , and has several advantages over low-levelmapping: 1. Identify...Label-Text XM.Xm_String_Create_L_To_R( "Welcome to the SABER Post-Processinq System’, XM.Xm STRING DEFAULTCHARSET ) XT.XtMakeArgList ( SIZE => 3, ARGS...about 2000 lines of Ada code) in one week’s worth of work. It was found that Page 9 r FOrm Approved REPORT DOCUMENTATION PAGE [orm Appr ove PUNK

  19. Automated flare prediction using the AdaBoost algorithm

    Institute of Scientific and Technical Information of China (English)

    Ru-Shi Lan; Yong Jiang; Liu-Guan Ding; Jian-Wei Yang

    2012-01-01

    We propose a flare prediction method based on the AdaBoost algorithm,which constructs a strong prediction model from a combination of several basic models.Three predictors,extracted from the photospheric magnetograms,are applied as features to predict the occurrence of flares with a certain level over 24 hours following the time when the magnetogram is recorded.To demonstrate the effectiveness of the proposed method,comparisons of experimental results with respect to some existing methods are given.The results show that an improvement is achieved in predicting the occurrences of large flares.

  20. Large distributed control system using ADA in fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, J. P., LLNL

    1998-04-21

    Construction of the National Ignition Facility laser at Lawrence Livermore National Laboratory features a large distributed control system constructed using object-oriented software engineering techniques. Control of 60,000 devices is effected using a network of some 500 computers that run software written in Ada and communicating through CORBA. The project has completed its final design review; implementation of the first of five planned increments will be delivered at the end of fiscal year 1998. Preliminary measures of the distributed controls performance confirm the design decisions reported in this paper, and the measurement and supporting simulation of full system performance continue.

  1. Event-based Implicit Invocation Decentralized in Ada

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Nowadays more and more attraction is drawn by the event-basedimplicit invocation - one of useful architectural patterns, because of its loose couplin g between components in the architecture and reactive integration in software sys tems. Analyzing object-oriented interaction with objects, this paper, based upo n the principle of software architecture, presents an approach on event-based ob j ect model with Ada exception handler. Consequently it is possible for us to impr ove, with adding specific architectural patterns, traditional programming langua ges into architectural description languages.

  2. ADaPPT: Enterprise Architecture Thinking for Information Systems Development

    Directory of Open Access Journals (Sweden)

    Hanifa Shah

    2011-01-01

    Full Text Available Enterprises have architecture: whether it is visible or invisible is another matter. An enterprises' architecture determines the way in which it works to deliver its business objectives and the way in which it can change to continue to meet its evolving business objectives. Enterprise architectural thinking can facilitate effective strategic planning and information systems development. This paper reviews enterprise architecture (EA and its concepts. It briefly considers EA frameworks. It describes the ADaPPT (Aligning Data, People, Processes and Technology EA approach as a means to managing organisational complexity and change. Future research directions are discussed.

  3. Ada Compiler Validation Summary Report: Certificate Number: 920509S1. 11259 Alenia Aeritalia and Selenia S.p.A DACS VAX/VMS to 80x86 PM MARA Ada Cross Compiler, Version 4.6 Microvax 4000/200 => MARA

    Science.gov (United States)

    1992-01-01

    INTERFACE exc. non ADA ------- v codice ADA exception ADA AH A AI .1 I sistema operativo exc. non ADA ------- - fig. 1- Function Exception Handling is...ASSIGN/NOLOG MYSYSoGRA ADA286_GRAPH $ ASSIGN/NOLOG NODALELABORATION.LNK NODAL ELABORATION $ ADA286/LINK/ LIBR -=MY ALB.ALB/OFD-[ ] / TEMPLATE

  4. TCP-ADaLR: TCP with adaptive delay and loss response for broadband GEO satellite networks

    OpenAIRE

    Omueti, Modupe Omogbohun

    2007-01-01

    Transmission Control Protocol (TCP) performance degrades in broadband geostationary satellite networks due to long propagation delays and high bit error rates. In this thesis, we propose TCP with algorithm modifications for adaptive delay and loss response (TCP-ADaLR) to improve TCP performance. TCP-ADaLR incorporates delayed acknowledgement mechanism recommended for Internet hosts. We evaluate and compare the performance of TCP-ADaLR, TCP SACK, and TCP NewReno, with and without delayed ackno...

  5. Phosphoribosylpyrophosphate (PRPP)-less mutants of Escherichia coli

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne

    1989-01-01

    R and prs-4::KanR were obtained. These strains were fully viable, but required guanosine, uridine, histidine, tryptophan and nicotinamide mononucleotide. There was no phosphoribosylpyrophosphate synthetase activity or phosphoribosylpyrophosphate pool in the mutant strains. These results show...

  6. Successful reconstitution of immunity in ADA-SCID by stem cell gene therapy following cessation of PEG-ADA and use of mild preconditioning.

    Science.gov (United States)

    Gaspar, H Bobby; Bjorkegren, Emma; Parsley, Kate; Gilmour, Kimberly C; King, Doug; Sinclair, Joanna; Zhang, Fang; Giannakopoulos, Aris; Adams, Stuart; Fairbanks, Lynette D; Gaspar, Jane; Henderson, Lesley; Xu-Bayford, Jin Hua; Davies, E Graham; Veys, Paul A; Kinnon, Christine; Thrasher, Adrian J

    2006-10-01

    Gene therapy is a promising treatment option for monogenic diseases, but success has been seen in only a handful of studies thus far. We now document successful reconstitution of immune function in a child with the adenosine deaminase (ADA)-deficient form of severe combined immunodeficiency (SCID) following hematopoietic stem cell (HSC) gene therapy. An ADA-SCID child who showed a poor response to PEG-ADA enzyme replacement was enrolled into the clinical study. Following cessation of enzyme replacement therapy, autologous CD34(+) HSCs were transduced with an ADA-expressing gammaretroviral vector. Gene-modified cells were reinfused following one dose of preconditioning chemotherapy. Two years after the procedure, immunological and biochemical correction has been maintained with progressive increase in lymphocyte numbers, reinitiation of thymopoiesis, and systemic detoxification of ADA metabolites. Sustained vector marking with detection of polyclonal vector integration sites in multiple cell lineages and detection of ADA activity in red blood cells suggests transduction of early hematopoietic progenitors. No serious side effects were seen either as a result of the conditioning procedure or due to retroviral insertion. Gene therapy is an effective treatment option for the treatment of ADA-SCID.

  7. Construction of a mutant strain of Streptococcus mutans with clpC-deletion to study the role of clpC ;gene in genetic competence%clpC 基因对变异链球菌感受态形成的影响

    Institute of Scientific and Technical Information of China (English)

    徐巧丽; 饶慧华; 马晓波; 黄朝阳; 郑港森; 张加勤; 宋秀宇

    2015-01-01

    目的:构建变异链球菌clpC缺陷突变株,检测该基因对变异链球菌感受态形成的影响。方法分别以变异链球菌UA159基因组和pIB107质粒为模板,PCR扩增clpC基因片段和卡那霉素基因盒(lox71-KMR-lox66);将clpC基因片段插入pMD-19T simple载体,经ClaⅠ/EcoRⅠ酶切、补平后连入卡那霉素基因盒,构建clpC缺陷突变同源重组载体pCKX2;SalⅠ线性化pCKX2并转化变异链球菌,卡那霉素筛选阳性菌落;质粒pCrePA转化阳性菌株,30℃培养剔除卡那霉素基因盒;37℃培养去除pCrePA,获得clpC缺陷突变株,PCR和测序鉴定;提取细菌总RNA并逆转录成cDNA,用RT-PCR法扩增clpC缺失序列的核苷酸片段并进行产物的电泳分析;pDL276分别转化变异链球菌和clpC缺陷突变株,观察感受态细胞形成变化。结果 PCR和测序结果证实成功构建同源重组载体pCKX2及变异链球菌clpC缺陷突变株;RT-PCR结果显示,△clpC缺失的核苷酸片段PCR产物电泳结果并无相应的条带出现;clpC缺陷突变株的感受态形成期延迟并延长维持期。结论 clpC基因具有负调控变异链球菌晚期感受态细胞形成的作用。%Objective To construct a mutant strain of Streptococcus mutans ( S.mutans ) with clpC-deletion and to investigate the role of clpC gene in genetic competence.Methods The fragment of clpC gene and the kanamycin resistant cassette flanked by two loxP sites were amplified by PCR.The purified fragment of clpC gene was cloned into pMD-19T simple vector to construct pCKX1.The pCKX1 vector was digested with ClaⅠ/EcoRⅠ, then blunted and introduced into lox71-KMR-lox66 to obtain pCKX2 vector via homologous recombination.The pCKX2 vector was linearized with SalⅠ and transformed into S.mutans UA159 strain.The positive strains constructed via homologous recombination were screened with kanamycin and transformed with the thermosensitive plasmid pCrePA.The KMR

  8. ADA3 regulates normal and tumor mammary epithelial cell proliferation through c-MYC.

    Science.gov (United States)

    Griffin, Nicolas I; Sharma, Gayatri; Zhao, Xiangshan; Mirza, Sameer; Srivastava, Shashank; Dave, Bhavana J; Aleskandarany, Mohammed; Rakha, Emad; Mohibi, Shakur; Band, Hamid; Band, Vimla

    2016-11-16

    We have established the critical role of ADA3 as a coactivator of estrogen receptor (ER), as well as its role in cell cycle progression. Furthermore, we showed that ADA3 is predominantly nuclear in mammary epithelium, and in ER+, but is cytoplasmic in ER- breast cancers, the latter correlating with poor survival. However, the role of nuclear ADA3 in human mammary epithelial cells (hMECs), and in ER+ breast cancer cells, as well as the importance of ADA3 expression in relation to patient prognosis and survival in ER+ breast cancer have remained uncharacterized. We overexpressed ADA3 in hMECs or in ER+ breast cancer cells and assessed the effect on cell proliferation. The expression of ADA3 was analyzed then correlated with the expression of various prognostic markers, as well as survival of breast cancer patients. Overexpression of ADA3 in ER- hMECs as well as in ER+ breast cancer cell lines enhanced cell proliferation. These cells showed increased cyclin B and c-MYC, decreased p27 and increased SKP2 levels. This was accompanied by increased mRNA levels of early response genes c-FOS, EGR1, and c-MYC. Analysis of breast cancer tissue specimens showed a significant correlation of ADA3 nuclear expression with c-MYC expression. Furthermore, nuclear ADA3 and c-MYC expression together showed significant correlation with tumor grade, mitosis, pleomorphism, NPI, ER/PR status, Ki67 and p27 expression. Importantly, within ER+ cases, expression of nuclear ADA3 and c-MYC also significantly correlated with Ki67 and p27 expression. Univariate Kaplan Meier analysis of four groups in the whole, as well as the ER+ patients showed that c-MYC and ADA3 combinatorial phenotypes showed significantly different breast cancer specific survival with c-MYC-high and ADA3-Low subgroup had the worst outcome. Using multivariate analyses within the whole cohort and the ER+ subgroups, the significant association of ADA3 and c-MYC expression with patients' outcome was independent of tumor grade

  9. TRW’s Ada Process Model for Incremental Development of Large Software Systems

    Science.gov (United States)

    1990-01-01

    TRW’s Ada Process Model has proven to be key to the Command Center Processing and Display System-Replacement (CCPDS-R) project’s success to data in...developing over 3000,000 lines of Ada source code executing in a distributed VAX VMS environment. The Ada Process Model is, in simplest terms, a...software progress metrics. This paper provides an overview of the techniques and benefits of the Ada Process Model and describes some of the experience and

  10. O tempo na terceira Enéada de Plotino

    Directory of Open Access Journals (Sweden)

    Daniel Schiochett

    2009-06-01

    Full Text Available Plotino é conhecido pela doutrina das três hipóstases: o Uno, a Inteligência e a Alma. Enquanto neoplatônico, sua doutrina é pensada a partir da visão platônica do mundo. Todavia, na terceira Enéada o filósofo se põe a discutir longamente a concepção antiga do tempo, fortemente devedora da doutrina aristotélica. Plotino, ao seu modo, consegue reinterpretar e adequar a noção aristotélica do tempo à concepção de mundo platônica. O tempo, para Plotino, por um lado, permanece referido ao movimento, concordando com Aristóteles, e por outro, é imagem de uma outra forma mais perfeira, a eternidade, concordando com a divisão do mundo em sensivel e supra-sensível de Platão. Por conseguir compreender o tempo a partir desses dois registros, o platônico e o aristotélico, Plotino figura como um ponto importante para se compreender as teorias do tempo que vieram depois dele, principalmente a de Santo Agostinho. Nosso ensaio pretende discutir a noção de tempo em Plotino, a partir da terceira Enéada, a fim de fornecer instrumentos para tal compreensão.

  11. New non detrimental DNA binding mutants of the Escherichia coli initiator protein DnaA

    DEFF Research Database (Denmark)

    Asklund, Marlene; Atlung, Tove

    2004-01-01

    an extensive mutational analysis of the DNA-binding domain of the Escherichia coli DnaA protein using mutagenic PCR. We analyzed mutants exhibiting more or less partial activity by selecting for complementation of a dnaA(Ts) mutant strain at different expression levels of the new mutant proteins. The selection...

  12. Mutants of Cercospora kikuchii altered in cercosporin synthesis and pathogenicity

    Energy Technology Data Exchange (ETDEWEB)

    Upchurch, R.G.; Walker, D.C.; Rollins, J.A.; Ehrenshaft, M.; Daub, M.E. (North Carolina State Univ., Raleigh (United States))

    1991-10-01

    The authors have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  13. Mutants of Cercospora kikuchii Altered in Cercosporin Synthesis and Pathogenicity.

    Science.gov (United States)

    Upchurch, R G; Walker, D C; Rollins, J A; Ehrenshaft, M; Daub, M E

    1991-10-01

    We have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  14. Autoimmune dysregulation and purine metabolism in adenosine deaminase (ADA-deficiency

    Directory of Open Access Journals (Sweden)

    Aisha Vanessa Sauer

    2012-08-01

    Full Text Available Genetic defects in the adenosine deaminase (ADA gene are among the most common causes for severe combined immunodeficiency (SCID. ADA-SCID patients suffer from lymphopenia, severely impaired cellular and humoral immunity, failure to thrive and recurrent infections. Currently available therapeutic options for this otherwise fatal disorder include bone marrow transplantation (BMT, enzyme replacement therapy with bovine ADA (PEG-ADA or hematopoietic stem cell gene therapy (HSC-GT. Although varying degrees of immune reconstitution can be achieved by these treatments, breakdown of tolerance is a major concern in ADA-SCID. Immune dysregulation such as autoimmune hypothyroidism, diabetes mellitus, hemolytic anemia, and immune thrombocytopenia are frequently observed in milder forms of the disease. However, several reports document similar complications also in patients on long-term PEG-ADA and after BMT or GT treatment.A skewed repertoire and decreased immune functions have been implicated in autoimmunity observed in certain B-cell and/or T-cell immunodeficiencies, but it remains unclear to what extent specific mechanisms of tolerance are affected in ADA deficiency. Herein we provide an overview about ADA-SCID and the autoimmune manifestations reported in these patients before and after treatment. We also assess the value of the ADA-deficient mouse model as a useful tool to study both immune and metabolic disease mechanisms. With focus on regulatory T and B cells we discuss the lymphocyte subpopulations particularly prone to contribute to the loss of self-tolerance and onset of autoimmunity in ADA deficiency. Moreover we address which aspects of immune dysregulation are specifically related to alterations in purine metabolism caused by the lack of ADA and the subsequent accumulation of metabolites with immunomodulatory properties.

  15. Phosphoribosylpyrophosphate synthetase of Escherichia coli, Identification of a mutant enzyme

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne; Nygaard, Per

    1982-01-01

    From an Escherichia coli purine auxotroph a mutant defective in phosphoribosylpyrophosphate (PRib-PP) synthetase has been isolated and partially characterized. In contrast to the parental strain, the mutant was able to grow on nucleosides as purine source, whereas growth on purine bases was reduced......, stimulated the mutant enzyme. The activity of PRib-PP synthetase in crude extract was higher in the mutant than in the parent. When starved for purines an accumulation of PRib-PP was observed in the parent strain, while the pool decreased in the mutant. During pyrimidine starvation derepression of PRib...

  16. Localization of transposon insertions in pathogenicity mutants of Erwinia amylovora and their biochemical characterization.

    Science.gov (United States)

    Bellemann, P; Geider, K

    1992-05-01

    Transposon Tn5, on a mobilizable ColE1 plasmid, on a Ti plasmid derepressed for bacterial transfer, and on the bacteriophage fd genome, was used to construct pathogenicity mutants of the fire blight pathogen Erwinia amylovora. Eleven nonpathogenic mutants were isolated from 1600 independent mutants screened. These mutants were divided into three types: auxotrophs, exopolysaccharide (EPS)-deficient mutants and a mutant of the dsp phenotype. According to their insertion sites the Tn5 mutants were mapped into several classes. Some of the mutants could be complemented with cosmid clones from a genomic library of the parent strain for EPS production on minimal agar. EPS-deficient mutants and the dsp mutant could complement each other to produce virulence symptoms on pear slices.

  17. Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

    Science.gov (United States)

    Kühl, J S; Schwarz, K; Münch, A; Schmugge, M; Pekrun, A; Meisel, C; Wahn, V; Ebell, W; von Bernuth, H

    2011-03-01

    Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA.

  18. Towards a rAAV-based gene therapy for ADA-SCID: from ADA deficiency to current and future treatment strategies.

    Science.gov (United States)

    Silver, Jared N; Flotte, Terence R

    2008-07-01

    Adenosine deaminase deficiency fosters a rare, devastating pediatric immune deficiency with concomitant opportunistic infections, metabolic anomalies and multiple organ system pathology. The standard of care for adenosine deaminase deficient severe combined immune deficiency (ADA-SCID) includes enzyme replacement therapy or bone marrow transplantation. Gene therapies for ADA-SCID over nearly two decades have exclusively involved retroviral vectors targeted to lymphocytes and hematopoetic progenitors. These groundbreaking gene therapies represent a revolution in clinical medicine, but come with several challenges, including the risk of insertional mutagenesis. An alternative gene therapy for ADA-SCID may utilize recombinant adeno-associated virus vectors in vivo, with numerous target tissues, to foster ectopic expression and secretion of adenosine deaminase. This review endeavors to describe ADA-SCID, the traditional treatments, previous retroviral gene therapies, and primarily, alternative recombinant adeno-associated virus-based strategies to remedy this potentially fatal genetic disease.

  19. Carrier frequency of a nonsense mutation in the adenosine deaminase (ADA) gene implies a high incidence of ADA-deficient severe combined immunodeficiency (SCID) in Somalia and a single, common haplotype indicates common ancestry.

    Science.gov (United States)

    Sanchez, Juan J; Monaghan, Gemma; Børsting, Claus; Norbury, Gail; Morling, Niels; Gaspar, H Bobby

    2007-05-01

    Inherited adenosine deaminase (ADA) deficiency is a rare metabolic disorder that causes immunodeficiency, varying from severe combined immunodeficiency (SCID) in the majority of cases to a less severe form in a small minority of patients. Five patients of Somali origin from four unrelated families, with severe ADA-SCID, were registered in the Greater London area. Patients and their parents were investigated for the nonsense mutation Q3X (ADA c7C>T), two missense mutations K80R (ADA c239A>G) and R142Q (ADA c425G>A), and a TAAA repeat located at the 3' end of an Alu element (AluVpA) positioned 1.1 kb upstream of the ADA transcription start site. All patients were homozygous for the haplotype ADA-7T/ADA-239G/ADA-425G/AluVpA7. Among 207 Somali immigrants to Denmark, the frequency of ADA c7C>T and the maximum likelihood estimate of the frequency of the haplotype ADA-7T/ADA-239G/ADA-425G/AluVpA7 were both 0.012 (carrier frequency 2.4%). Based on the analysis of AluVpA alleles, the ADA c7C/T mutation was estimated to be approximately 7,100 years old. Approximately 1 out of 5 - 10000 Somali children will be born with ADA deficiency due to an ADA c7C/T mutation, although within certain clans the frequency may be significantly higher. ADA-SCID may be a frequent immunodeficiency disorder in Somalia, but will be underdiagnosed due to the prevailing socioeconomic and nutritional deprivation.

  20. Spontaneous Nif- mutants of Rhodopseudomonas capsulata.

    OpenAIRE

    Wall, J D; Love, J.; Quinn, S P

    1984-01-01

    Revertible, spontaneous Nif- mutants of Rhodopseudomonas capsulata have been shown to accumulate in cultures growing photosynthetically with an amino acid as the nitrogen source such that H2 is maximally produced. The majority of such strains carry mutations which are clustered in a short region of the chromosome, probably representing one or two genes. Because this cluster includes temperature-sensitive mutations, it is also likely that it identifies the structural gene of a polypeptide. The...

  1. Comparative production of cellulases by mutants of Trichoderma parceramosume PTCC5140

    Directory of Open Access Journals (Sweden)

    Hoda Nouri

    2017-06-01

    Discussion and conclusion: Evaluation of cellulase production in mutant strains of Trichoderma parceramosume PTCC 5140 showed that use of chemical mutagenesis with 2 to 11 fold increasing in enzyme activity is a potent method to improve cellulase complex activity. In the current study, obtained mutant strains could be introduced as a potent cellulase producer for further studies in bioconversion processes.

  2. Ada Compiler Validation Summary Report: Siemens AG Siemens BS2000 Ada Compiler, Version 1.0 Siemens 7.57OP.

    Science.gov (United States)

    1987-02-26

    STD-]815A, FEB 1983. 2. Ada Validation Organization: Policies and Procedures, MITRE Corporation , JUN 1982, PB 83-110601. 3. Ada Compiler Validation...expression’s suhtyne is comnatible with the target’s sub- type. In assigning two-dimensional array types, the expression does not appear to be evaluated...owner’s corporate name. Siemens Aktiengesellschaft -- 7 ,Spa . ’. ’.,,,, .- ’.% ’ " ’ ,-.-,ŗ’/ ,’,’ ’ ’,,- ’ % 3

  3. Phanerochaete mutants with enhanced ligninolytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Kakar, S.N.; Perez, A.; Gonzales, J.

    1993-06-01

    In addition to lignin, the white rot fungus Phanerochaete chrysosporium has the ability to degrade a wide spectrum of recalcitrant organopollutants in soils and aqueous media. Although some of the organic compounds are degraded under nonligninolytic conditions, most are degraded under ligninolytic conditions with the involvement of the extracellular enzymes, lignin peroxidases, and manganese-dependent peroxidases, which are produced as secondary metabolites triggered by conditions of nutrient starvation (e.g., nitrogen limitation). The fungus and its enzymes can thus provide alternative technologies for bioremediation, biopulping, biobleaching, and other industrial applications. The efficiency and effectiveness of the fungus can be enhanced by increasing production and secretion of the important enzymes in large quantities and as primary metabolites under enriched conditions. One way this can be achieved is through isolation of mutants that are deregulated or are hyperproducers or supersecretors of key enzymes under enriched conditions. Through ultraviolet-light and gamma-rays mutagenesis we have isolated a variety of mutants, some of which produce key enzymes of the ligninolytic system under high-nitrogen growth conditions. One of the mutants produced 272 units (U) of lignin peroxidases enzyme activity per liter after nine days under high nitrogen. The mutant and the parent strains produced up to 54 U/L and 62 U/L, respectively, of the enzyme activity under low-nitrogen growth conditions during this period. In some experiments the mutant showed 281 U/L of enzyme activity under high nitrogen after 17 days.

  4. 基于AdaCostBoost算法的网络钓鱼检测%Phishing Detection System Based on AdaCostBoost Algorithm

    Institute of Scientific and Technical Information of China (English)

    曾传璜; 李思强; 张小红

    2015-01-01

    针对日益严重的网络钓鱼攻击,提出机器学习的方法进行钓鱼网站的检测和判断。首先,根据URL提取敏感特征,然后,采用AdaBoost算法进行训练出分类器,再用训练好的分类器对未知URL检测识别。最后,针对非平衡代价问题,采用了改进后的 AdaBoost 算法--AdaCostBoost,加入代价因子的计算。实验结果表明,文中提出的网络钓鱼检测方法,具有较优的检测性能。%For increasing serious phishing attacks, machine-learning method is proposed to detect phishing webs. Firstly, sensitive features are extracted from the URL, then, using AdaBoost algorithm to get the trained classifier, and then the classifier is used to detect unknown URLs. Finally, considering of non-equilibrium problems of AdaBoost, the paper puts forward the improved learning algorithm called AdaCostBoost, which contains computation of cost factors. According to the experiment result, the proposed phishing detection method has better detection performance.

  5. Cartalk 2000: development of a co-operative ADAS based on vehicle-to-vehicle communication

    NARCIS (Netherlands)

    Morsink, P.L.J.; Hallouzi, R.; Dagli, I.; Cseh, C.; Schäfers, L.; Nelisse, M.W.; Bruin, D. de

    2003-01-01

    Advanced Driver Assistance Systems (ADAS) benefit from using vehicle-to-vehicle communication. In the 5th framework EC project CarTALK2000 co-operative ADAS are designed, tested and evaluated with respect to increasing traffic safety, efficiency and driving comfort. Communication based longitudinal

  6. NRPA Law Review. Combat Karate Class Illustrates ADA "Direct Threat" Exception.

    Science.gov (United States)

    Kozlowski, James C.

    2000-01-01

    Describes the Americans with Disabilities Act (ADA), which prohibits discrimination against people with disabilities, highlighting a lawsuit involving a boy with AIDS who was barred from a traditional combat-oriented martial arts school. Courts ruled that his exclusion did not violate the ADA because he posed significant health and safety risks to…

  7. NRPA Law Review. Combat Karate Class Illustrates ADA "Direct Threat" Exception.

    Science.gov (United States)

    Kozlowski, James C.

    2000-01-01

    Describes the Americans with Disabilities Act (ADA), which prohibits discrimination against people with disabilities, highlighting a lawsuit involving a boy with AIDS who was barred from a traditional combat-oriented martial arts school. Courts ruled that his exclusion did not violate the ADA because he posed significant health and safety risks to…

  8. The G22A Polymorphism of the ADA Gene and Susceptibility to Autism Spectrum Disorders

    Science.gov (United States)

    Hettinger, Joe A.; Liu, Xudong; Holden, Jeanette Jeltje Anne

    2008-01-01

    Inborn errors of purine metabolism have been implicated as a cause for some cases of autism. This hypothesis is supported by the finding of decreased adenosine deaminase (ADA) activity in the sera of some children with autism and reports of an association of the A allele of the ADA G22A (Asp8Asn) polymorphism in individuals with autism of…

  9. The "Ada" Verb of Being in Bahasa Malaysia. Colorado Research in Linguistics, No. 4.

    Science.gov (United States)

    Mader, Robin

    This paper examines the various syntactic and semantic functions of the "ada" verb of "being" in Malay. The claim is made that there is an abstract uppermost "ada" in the underlying structure of Malay sentences that asserts or denies the truth of the surface main clause. A further claim is made that the…

  10. School Issues Under [Section] 504 and the ADA: The Latest and Greatest.

    Science.gov (United States)

    Aleman, Steven R.

    This paper highlights recent guidance and rulings from the Office of Civil Rights (OCR) of interest to administrators, advocates, and attorneys. It is a companion piece to Student Issues on SectionNB504/ADA: The Latest and Greatest. Compliance with SectionNB504 and the Americans with Disabilities Act (ADA) continues to involve debate and dialog on…

  11. Clinical utility of interferon-γ compared to ADA in tuberculous pleural effusion

    Directory of Open Access Journals (Sweden)

    Nariman A. Helmy

    2012-10-01

    Result: Our results demonstrate that the pleural fluid concentrations of ADA, INF-γ in patients with tuberculous pleural effusions are significantly higher than in other effusions. Most importantly, ROC analysis clearly demonstrated ADA to be more sensitive and specific than INF-γ for diagnosis of tuberculous pleuritis.

  12. School Issues Under [Section] 504 and the ADA: The Latest and Greatest.

    Science.gov (United States)

    Aleman, Steven R.

    This paper highlights recent guidance and rulings from the Office of Civil Rights (OCR) of interest to administrators, advocates, and attorneys. It is a companion piece to Student Issues on SectionNB504/ADA: The Latest and Greatest. Compliance with SectionNB504 and the Americans with Disabilities Act (ADA) continues to involve debate and dialog on…

  13. Large distributed control system using Ada in fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Van Arsdall, P J; Woodruff, J P

    1998-08-11

    Construction of the National Ignition Facility laser at Lawrence Livermore National Laboratory features a distributed control system that uses object-oriented software engineering techniques. Control of 60,000 devices is effected using a network of some 500 computers. The software is being written in Ada and communicates through CORBA. Software controls are implemented in two layers: individual device controllers and a supervisory layer. The software architecture provides services in the form of frameworks that address issues common to event-driven control systems. Those services are allocated to levels that strictly prescribe their interdependency so the levels are separately reusable. The project has completed its final design review. The delivery of the first increment takes place in October 1998. Keywords Distributed control system, object-oriented development, CORBA, application frameworks, levels of abstraction

  14. O tempo na terceira Enéada de Plotino

    OpenAIRE

    Daniel Schiochett

    2009-01-01

    Plotino é conhecido pela doutrina das três hipóstases: o Uno, a Inteligência e a Alma. Enquanto neoplatônico, sua doutrina é pensada a partir da visão platônica do mundo. Todavia, na terceira Enéada o filósofo se põe a discutir longamente a concepção antiga do tempo, fortemente devedora da doutrina aristotélica. Plotino, ao seu modo, consegue reinterpretar e adequar a noção aristotélica do tempo à concepção de mundo platônica. O tempo, para Plotino, por um lado, permanece referido ao moviment...

  15. The implementation and use of Ada on distributed systems with reliability requirements

    Science.gov (United States)

    Reynolds, P. F.; Knight, J. C.; Urquhart, J. I. A.

    1983-01-01

    The issues involved in the use of the programming language Ada on distributed systems are discussed. The effects of Ada programs on hardware failures such as loss of a processor are emphasized. It is shown that many Ada language elements are not well suited to this environment. Processor failure can easily lead to difficulties on those processors which remain. As an example, the calling task in a rendezvous may be suspended forever if the processor executing the serving task fails. A mechanism for detecting failure is proposed and changes to the Ada run time support system are suggested which avoid most of the difficulties. Ada program structures are defined which allow programs to reconfigure and continue to provide service following processor failure.

  16. Isolation and characterization of Streptococcus mutans mutants defective in adherence and aggregation.

    OpenAIRE

    Murchison, H; Larrimore, S; Curtiss, R

    1981-01-01

    A method was developed which enriched for mutants of Streptococcus mutans that exhibit defects in adherence to glass, aggregation, or both. Mutants were isolated from derivatives of strains PS14 (serotype c) and 6715 (serotype g) after mutagenesis with either ethyl methane sulfonate or nitrous acid. Cell survival after mutagenesis was kept above 1 to 2% to enhance the probability that mutants resulted from single mutational events. A total of 117 mutants were isolated; they also displayed non...

  17. Carrier frequency of a nonsense mutation in the adenosine deaminase (ADA) gene implies a high incidence of ADA-deficient severe combined immunodeficiency (SCID) in Somalia and a single, common haplotype indicates common ancestry

    DEFF Research Database (Denmark)

    Sanchez Sanchez, Juan Jose; Monaghan, Gemma; Børsting, Claus

    2007-01-01

    , with severe ADA-SCID, were registered in the Greater London area. Patients and their parents were investigated for the nonsense mutation Q3X (ADA c7C>T), two missense mutations K80R (ADA c239A>G) and R142Q (ADA c425G>A), and a TAAA repeat located at the 3' end of an Alu element (AluVpA) positioned 1.1 kb...

  18. Digital data sets that describe aquifer characteristics of the Vamoosa-Ada aquifer in east-central Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digitized polygons of constant hydraulic conductivity values for the Vamoosa-Ada aquifer in east-central Oklahoma. The Vamoosa-Ada aquifer...

  19. Digital data sets that describe aquifer characteristics of the Vamoosa-Ada aquifer in east-central Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digitized water-level elevation contours for the Vamoosa-Ada aquifer in east-central Oklahoma. The Vamoosa-Ada aquifer is an important...

  20. Digital data sets that describe aquifer characteristics of the Vamoosa-Ada aquifer in east-central Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digitized polygons of constant recharge values for the Vamoosa-Ada aquifer, in east-central Oklahoma. The Vamoosa-Ada aquifer is an...

  1. Digital data sets that describe aquifer characteristics of the Vamoosa-Ada aquifer in east-central Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digitized aquifer boundaries for the Vamoosa-Ada aquifer in east-central Oklahoma. The Vamoosa-Ada aquifer is an important source of water...

  2. 腺苷脱氨酶(ADA)微量测定法的研究%Reseach on ADA Microtiter Method

    Institute of Scientific and Technical Information of China (English)

    侯超; 王新宁

    2003-01-01

    目的:设计一种用于检测腺苷脱氨酶微量(ADA)的微量检测方法.方法:通过对实验方法的改进,利用酶标仪进行比色.结果:将微量法所得结果(大于50 U/L的标本需稀释后重新测定)与常规的比色法进行配对比较下,两方法无显著性差异,t=1.51,0.10<P<0.20.结论:在常规工作中可用微量法替代氨试剂比色法,若遇到大于50U/L的标本,稀释后再进行测定.

  3. Selection of a recombinant Marek's disease virus in vivo through expression of the Marek's EcoRI-Q (Meq)-encoded oncoprotein: characterization of an rMd5-based mutant expressing the Meq of strain RB-1B.

    Science.gov (United States)

    Kumar, Pankaj; Dong, Huimin; Lenihan, Dawn; Gaddamanugu, Syamsundar; Katneni, Upendra; Shaikh, Shireen; Tavlarides-Hontz, Phaedra; Reddy, Sanjay M; Peters, Wachen; Parcells, Mark S

    2012-06-01

    Marek's disease (MD) is a highly contagious viral disease of chickens (Gallus gallus domesticus) caused by MD virus (MDV), characterized by paralysis, neurologic signs, and the rapid onset of T-cell lymphomas. MDV-induced T-cell transformation requires a basic leucine zipper protein called Marek's EcoRI-Q-encoded protein (Meq). We have identified mutations in the coding sequence of Meq that correlated with virus pathotype (virulent, very virulent, and very virulent plus). The aim of this study was to determine whether recombinant viruses could be isolated based on Meq expression through in vivo selection. Chicken embryo fibroblasts (CEFs) were cotransfected with an rMd5 strain-based Meq deletion virus (rMd5deltaMeq) and meq loci from strains representing different pathotypes of MDV. Transfected CEFs were inoculated into chickens in two independent studies. We were able to isolate a single recombinant virus, rMDV-1137, in a contact-exposed chicken. rMDV-1137 had recombined two copies of the meq gene of RB-1B and was found to have pathogenicity similar to both RB-1B and rMd5 parental strains. We found the RB-1B- and rMd5-induced lymphomas showed differences in composition and that rMDV-1137-induced lymphomas were intermediate in their composition. We were able to establish cell lines from both RB-1B- (MDCC-UD35, -UD37) and rMDV-1137 (MDCC-UD36, -UD38)-induced, but not rMd5-induced, lymphomas. To date, no rMd5- or parent Md5-transformed T-cell lines have been reported. Our results suggest that 1) a recombinant MDV can be selected on the basis of oncogenicity; 2) changes in Meq sequence seem to affect tumor composition and the ability to establish cell lines; and 3) in addition to meq, other genomic loci affect MDV pathogenicity and oncogenicity.

  4. 炭疽芽孢杆菌A16R株lysA基因缺失突变株的构建%Construction of lysA deletion mutant of Bacillus anthracis vaccine strain A16R

    Institute of Scientific and Technical Information of China (English)

    高飞; 王东澍; 冯尔玲; 朱力; 王恒樑; 廖祥儒; 刘先凯

    2013-01-01

    Objective To construct the lysA site-deleted mutagenesis of Bacillus anthracis vaccine strain A16R in order to provide scientific reference for subsequent study on quantitative proteomics. Methods Using lysA Site-deleted mutagenesis as the target gene, software was used to design primers of upstream and downstream of lysA and antibiotic resistance genes. The recombinant plasmid was constructed by inserting three fragments into the vector and electroporated into competence A16R cells. Finally, A16R mutagenesis strain was screened and verified. Growth curves of the mutagenesis strain and wild strain were drawn, and physiological and biochemical characteristics were analyzed. Result and Conclusion lysA Site-deleted mutagenesis is obtained, contributing to quantitative proteomics research and establishing a good technical platform for functional genomics research of B. anthracis.%目的 构建炭疽芽孢杆菌(Bacillus anthracis)A16R株lysA基因缺失突变株,为后续的定量蛋白质组学研究奠定基础.方法 以炭疽杆菌活疫苗A16R株lysA基因为目的缺失基因,利用软件设计上下游同源臂以及抗性基因的引物,用同源重组酶将3个片段连入质粒中,构建重组质粒,并将重组质粒导入炭疽杆菌A16R感受态细胞中,筛选炭疽杆菌A16R株lysA基因缺失突变株,对其进行验证.最后绘制缺失突变株和野生株生长曲线并进行生理生化分析.结果 成功构建了重组质粒,经同源重组后获得lysA基因缺失突变株.鉴定表明目的基因已经丢失.结论 成功获得炭疽杆菌A16R株lysA基因缺失突变株,为定量蛋白质组学研究奠定了基础,也为炭疽杆菌重要基因功能的研究建立了良好的技术平台.

  5. Phanerochaete mutants with enhanced ligninolytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Kakar, S.N.; Perez, A.; Gonzales, J. (Argonne National Lab., IL (United States))

    In addition to lignin, the white rot fungus Phanerochaete chrysosporium has the ability to degrade a wide spectrum of recalcitrant organopollutants in soils and aqueous media. Most of the organic compounds are degraded under ligninolytic conditions with the involvement of the extracellular enzymes, lignin peroxidases, and manganese-dependent peroxidases, which are produced as secondary metabolites triggered by conditions of nutrient starvation (e.g., nitrogen limitation). The fungus and its enzymes can thus provide alternative technologies for bioremediation, biopulping, biobleaching, and other industrial applications. The efficiency and effectiveness of the fungus can be enhanced by increasing production and secretion of the important enzymes in large quantities and as primary metabolites under enriched conditions. One way this can be achieved is through isolation of mutants that are deregulated, or are hyperproducers or supersectors of key enzymes under enriched conditions. Through UV-light and [gamma]-ray mutagenesis, the authors have isolated a variety of mutants, some of which produce key enzymes of the ligninolytic system under high-nitrogen growth conditions. One of the mutants, 76UV, produced 272 U of lignin peroxidases enzyme activity/L after 9 d under high nitrogen (although the parent strain does not produce this enzyme under these conditions). The mutant and the parent strains produced up to 54 and 62 U/L, respectively, of the enzyme activity under low-nitrogen growth conditions during this period. In some experiments, the mutant showed 281 U/L of enzyme activity under high nitrogen after 17 d. 17 refs., 1 fig., 3 tabs.

  6. Construction and characterization of invasion protein B gene deleted mutant of Salmonella typhimurium SL1344 strain%鼠伤寒沙门菌SL1344株侵袭性蛋白B缺失株的构建及生物学特性

    Institute of Scientific and Technical Information of China (English)

    陈松彪; 陈桂华; 赵战勤; 李静; 郁川; 何雷; 张春杰; 程相朝; 李银聚; 颜云飞; 金修哲

    2015-01-01

    Objective:In order to develop a safer vaccine strain exploit Salmonella typhimurium vaccine strain .A ΔsipB mutant of Salmonella typhimurium SL 1344 strain was constructed.Methods: Firstly, the recombinant suicide plasmid containing the missing 585 bp sipB ( PREΔsipB ) was built by homologous recombination , and screenned by two-step method.Results: PCR and sequencing results showed that SL 1344ΔsipB was successfully constructed.It was no significant changes compared with SL 1344.But compared with the parent strains SL 1344 , the mutant strain had obvious change in its virulence , oral challenge of bacteria in mice revealed that LD50 of the mutant strain was 1.70 ×108 CFU,the toxicity reduced about 1.4%.The protection rate induced by the sipB mutant was 50%,and the serum antibody peaked 14 d post-immunization.Conclusion:The SL1344ΔsipB mutant was constructed suc-cessfully,and genetic stability ,significantly reduced virulence.The study provides a new approach for further study of the relationship between the gene and pathogenicity of Salmonella typhimurium.It is likely that the ΔsipB mutant could be adapted to develope attenuated Salmonella vaccine.%目的:为了研制更加安全的鼠伤寒沙门菌弱毒株,本研究构建了鼠伤寒沙门菌SL1344ΔsipB基因缺失突变株。方法:首先构建含缺失585 bp sipB基因的重组自杀性质粒PREΔsipB,利用重组自杀性质粒介导的等位基因交换技术,两步法筛选出SL1344的sipB缺失株。结果:PCR及测序结果表明SL1344ΔsipB构建成功。进一步生物学特性研究表明,缺失株SL1344ΔsipB保留了亲本菌株SL1344的血清型1,4,5,12:i:1,2,且能够稳定遗传缺失585 bp的sipB基因,生长速度没有发生明显改变;但是,与亲本株SL1344相比,其毒力发生明显改变,缺失株SL1344ΔsipB口服感染6周龄BALB/c小鼠的LD50为1.70×108 CFU,毒力较亲本株SL1344降低至1.4%,免疫

  7. Widely Used Herpes Simplex Virus 1 ICP0 Deletion Mutant Strain dl1403 and Its Derivative Viruses Do Not Express Glycoprotein C Due to a Secondary Mutation in the gC Gene.

    Directory of Open Access Journals (Sweden)

    Cristina W Cunha

    Full Text Available Herpes simplex virus 1 (HSV-1 ICP0 is a multi-functional phosphoprotein expressed with immediate early kinetics. An ICP0 deletion mutant, HSV-1 dl1403, has been widely used to study the roles of ICP0 in the HSV-1 replication cycle including gene expression, latency, entry and assembly. We show that HSV-1 dl1403 virions lack detectable levels of envelope protein gC, and that gC is not synthesized in infected cells. Sequencing of the gC gene from HSV-1 dl1403 revealed a single amino acid deletion that results in a frameshift mutation. The HSV-1 dl1403 gC gene is predicted to encode a polypeptide consisting of the original 62 N-terminal amino acids of the gC protein followed by 112 irrelevant, non-gC residues. The mutation was also present in a rescuant virus and in two dl1403-derived viruses, D8 and FXE, but absent from the parental 17+, suggesting that the mutation was introduced during the construction of the dl1403 virus, and not as a result of passage in culture.

  8. Regulation of adenosine deaminase (ADA) on induced mouse experimental autoimmune uveitis (EAU) ‡

    Science.gov (United States)

    Liang, Dongchun; Zuo, Aijun; Zhao, Ronglan; Shao, Hui; Kaplan, Henry J.; Sun, Deming

    2016-01-01

    Adenosine is an important regulator of the immune response and adenosine deaminase (ADA) inhibits this regulatory effect by converting adenosine into functionally inactive molecules. Studies have shown that adenosine receptor (AR) agonists can be either anti- or pro-inflammatory. Clarification of the mechanisms that cause these opposing effects should provide a better guide for therapeutic intervention. In this study, we investigated the effect of ADA on the development of experimental autoimmune uveitis (EAU) induced by immunizing EAU-prone mice with a known uveitogenic peptide, IRBP1–20. Our results showed that the effective time to administer a single dose of ADA to suppress induction of EAU was 8–14 days post-immunization, shortly before EAU expression, but ADA treatment at other time points exacerbated disease. ADA preferentially inhibited Th17 responses and this effect was γδ T cell-dependent. Our results demonstrated that the existing immune status strongly influences the anti- or proinflammatory effects of ADA. Our observations should help improve the design of ADA- and AR-targeted therapies. PMID:26856700

  9. Molecular analysis of mutants of the Neurospora adenylosuccinate synthetase locus

    Indian Academy of Sciences (India)

    A. Wiest; A. J. McCarthy; R. Schnittker; K. McCluskey

    2012-08-01

    The ad-8 gene of Neurospora crassa, in addition to being used for the study of purine biology, has been extensively studied as a model for gene structure, mutagenesis and intralocus recombination. Because of this there is an extensive collection of well-characterized N. crassa ad-8 mutants in the Fungal Genetics Stock Center collection. Among these are spontaneous mutants and mutants induced with X-ray, UV or chemical mutagens. The specific lesions in these mutants have been genetically mapped at high resolution. We have sequenced the ad-8 locus from 13 of these mutants and identified the molecular nature of the mutation in each strain. We compare the historical fine-structure map to the DNA and amino acid sequence of each allele. The placement of the individual lesions in the fine-structure map was more accurate at the 5′ end of the gene and no mutants were identified in the 3′ untranslated region of this gene. We additionally analysed ad-8+ alleles in 18 N. crassa strains subjected to whole-genome sequence analysis and describe the variability among Neurospora strains and among fungi and other organisms.

  10. 基于改进的AdaBoost人脸检测算法的研究%Research on Face Detection Based on Improved AdaBoost Algorithm

    Institute of Scientific and Technical Information of China (English)

    丁知平

    2013-01-01

    Face detection is a fundamental research theme in the topic of computer vision ,and it has a broad application in many fields such as video surveillance,automatic face recognition,etc. To improve the detection speed of AdaBoost based face detection algorithm, proposes a rapid im-proved AdaBoost based face detection algorithm. Experiments shows that, compared with the current algorithm less features are selected in the inspection, and a high detection correct rate is achieved with the proposed algorithm.%  人脸检测是计算机视觉领域的基础研究,在视频监控、自动人脸识别等领域有着重要应用价值。针对传统的AdaBoost算法用于人脸检测时需要的特征数目多、检测速度慢的问题,提出一种基于改进的AdaBoost人脸检测算法。实验结果表明,相对于传统的AdaBoost人脸检测算法,该算法使用较少的特征即可达到较高的检测准确率,检测速度得到显著提高。

  11. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1

    Science.gov (United States)

    Gottschalk, Leda Maria Fortes; de Sousa Paredes, Raquel; Teixeira, Ricardo Sposina Sobral; da Silva, Ayla Sant’Ana; da Silva Bon, Elba Pinto

    2013-01-01

    The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 °C and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture. PMID:24294256

  12. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1

    Directory of Open Access Journals (Sweden)

    Leda Maria Fortes Gottschalk

    2013-01-01

    Full Text Available The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L, which was not detected in the T. reesei culture.

  13. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1.

    Science.gov (United States)

    Gottschalk, Leda Maria Fortes; de Sousa Paredes, Raquel; Teixeira, Ricardo Sposina Sobral; da Silva, Ayla Sant'Ana; da Silva Bon, Elba Pinto

    2013-01-01

    The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 °C and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture.

  14. [Eremothecium ashbyii mutants resistant to 2,6-diaminopurine].

    Science.gov (United States)

    Stepanov, A I; Beburov, M Iu; Zhdanov, V G

    1975-01-01

    3 groups of Eremothecium ashbyii mutants resistant to 5-10(-3) M 2,6-diaminopurine (DAP) ahve been obtained. The mutants of the 1st group (Dap-r) are selected from the initial susceptible strain by the ability to grow in the presence of 5-10(-3) M DAP. The mutants of the 2nd group (Azg-Dap-r) are selected in the selective background of two analogues of 5-10(-3) M DAP and 10(-4) M 8-azaguanine (AG). The mutants of the 3rd group (Azg-r - DAP-r) are isolated from the mutant Azg-r 34 resistant to 10(-4) M AG. The results of studying cross-resistance of mutants to DAP, AG and 8-azaadenine (AA) show that Dap-r and Azg-Dap-r mutants in contrast to Azg-r - Dap-r, have common phenotypic properties and can grow only on the analogues of adenine. DAP, but not AA, eliminates the inhibitory effect of AG on the growth of these mutants. This effect is probably due to deaminating DAP to guanine. Mutants Azg-r - Dap-r retain the initial resistance to 10(-4) M AG, but are susceptible to higher concentrations of AG and in this case DAP does not eliminate the inhibitory effect of AG. In all mutants obtained the effectiveness of the incorporation of 14C-adenine (but not 14C-guanine) is sharply reduced, thus indicating the absence of adenosine-monophosphate pyrophosphorylase activity. The mutants do not excrete purine-like compounds into the medium. In the course of the continuous growth of mutants in the presence of DAP but not of guanine the red intracellular pigment is formed which seems to be a complex of riboflavin with DAP. A disturbance in the synthesis of adenosine monophosphate pyrophosphorylase does not influence practically the level of the synthesis of riboflavin in E. ashbyii.

  15. Thermal-Work Strain and Energy Expenditure during Marine Rifle Squad Operations in Afghanistan (August 2013)

    Science.gov (United States)

    2015-08-10

    TECHNICAL REPORT NO. T15-7 DATE August 2015 ADA THERMAL-WORK STRAIN AND ENERGY EXPENDITURE ...USARIEM TECHNICAL REPORT T15-7 THERMAL-WORK STRAIN AND ENERGY EXPENDITURE DURING MARINE RIFLE SQUAD OPERATIONS IN AFGHANISTAN...0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for

  16. Mutant prevention concentration and mutant selection window for 10 antimicrobial agents against Rhodococcus equi.

    Science.gov (United States)

    Berghaus, Londa J; Giguère, Steeve; Guldbech, Kristen

    2013-10-25

    The objectives of this study were to determine the mutant prevention concentration (MPC), time above the MPC and mutant selection window for 10 antimicrobial agents against Rhodococcus equi and to determine if the combination of a macrolide with rifampin would decrease emergence of resistant mutants. Antimicrobial agents investigated (erythromycin, clarithromycin, azithromycin, rifampin, amikacin, gentamicin, enrofloxacin, vancomycin, imipenem, and doxycycline) were selected based on in vitro activity and frequency of use in foals or people infected with R. equi. Each antimicrobial agent or combination of agents was evaluated against four virulent strains of R. equi. MPC were determined using an agar plate assay. Pharmacodynamic parameters were calculated using published plasma and pulmonary pharmacokinetic variables. There was a significant (Pequi. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Connexin mutants and cataracts

    Directory of Open Access Journals (Sweden)

    Eric C Beyer

    2013-04-01

    Full Text Available The lens is a multicellular, but avascular tissue that must stay transparent to allow normal transmission of light and focusing of it on the retina. Damage to lens cells and/or proteins can cause cataracts, opacities that disrupt these processes. The normal survival of the lens is facilitated by an extensive network of gap junctions formed predominantly of connexin46 and connexin50. Mutations of the genes that encode these connexins (GJA3 and GJA8 have been identified and linked to inheritance of cataracts in human families and mouse lines. In vitro expression studies of several of these mutants have shown that they exhibit abnormalities that may lead to disease. Many of the mutants reduce or modify intercellular communication due to channel alterations (including loss of function or altered gating or due to impaired cellular trafficking which reduces the number of gap junction channels within the plasma membrane. However, the abnormalities detected in studies of other mutants suggest that they cause cataracts through other mechanisms including gain of hemichannel function (leading to cell injury and death and formation of cytoplasmic accumulations (that may act as light scattering particles. These observations and the anticipated results of ongoing studies should elucidate the mechanisms of cataract development due to mutations of lens connexins and abnormalities of other lens proteins. They may also contribute to our understanding of the mechanisms of disease due to connexin mutations in other tissues.

  18. Ada compiler evaluation on the Space Station Freedom Software Support Environment project

    Science.gov (United States)

    Badal, D. L.

    1989-01-01

    This paper describes the work in progress to select the Ada compilers for the Space Station Freedom Program (SSFP) Software Support Environment (SSE) project. The purpose of the SSE Ada compiler evaluation team is to establish the criteria, test suites, and benchmarks to be used for evaluating Ada compilers for the mainframes, workstations, and the realtime target for flight- and ground-based computers. The combined efforts and cooperation of the customer, subcontractors, vendors, academia and SIGAda groups made it possible to acquire the necessary background information, benchmarks, test suites, and criteria used.

  19. CITY GROUND DESIGN AND THE IMAGE OF THE CITY: THE PORTUGUESE CALÇADA

    Directory of Open Access Journals (Sweden)

    Antoni Remesar

    2014-10-01

    The pavement-form - including the "calçada-form"-is at the root of some of the flagship operations creating the image of the city (Havana, 1928; Alicante, 1957; the Ramblas in Barcelona, 1969; reform of the Avenida Atlantica in Rio by Burle Marx, 1970. However, these same operations show that the "form-calçada" does not meet many of the requirements of economy, security or universal accessibility required by the contemporary city. In the paper was to analyze the causes and reasons that hover over the announced death of calçada á Portugueza.

  20. Cytokinin production by plant growth promoting rhizobacteria and selected mutants.

    Science.gov (United States)

    García de Salamone, I E; Hynes, R K; Nelson, L M

    2001-05-01

    One of the proposed mechanisms by which rhizobacteria enhance plant growth is through the production of plant growth regulators. Five plant growth promoting rhizobacterial (PGPR) strains produced the cytokinin dihydrozeatin riboside (DHZR) in pure culture. Cytokinin production by Pseudomonas fluorescens G20-18, a rifampicin-resistant mutant (RIF), and two TnphoA-derived mutants (CNT1, CNT2), with reduced capacity to synthesize cytokinins, was further characterized in pure culture using immunoassay and thin layer chromatography. G20-18 produced higher amounts of three cytokinins, isopentenyl adenosine (IPA), trans-zeatin ribose (ZR), and DHZR than the three mutants during stationary phase. IPA was the major metabolite produced, but the proportion of ZR and DHZR accumulated by CNT1 and CNT2 increased with time. No differences were observed between strain G20-18 and the mutants in the amounts of indole acetic acid synthesized, nor were gibberellins detected in supernatants of any of the strains. Addition of 10(-5) M adenine increased cytokinin production in 96- and 168-h cultures of strain G20-18 by approximately 67%. G20-18 and the mutants CNT1 and CNT2 may be useful for determination of the role of cytokinin production in plant growth promotion by PGPR.

  1. Isolation and characterization of Rhizobium meliloti mutants affected in exopolysaccharide production.

    Science.gov (United States)

    Rodríguez-Navarro, D N; Palomares, A J; Casadesús, J

    1991-06-01

    Rhizobium meliloti mutants affected in the production of exopolysaccharide (EPS) were isolated after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. The mutants were classified into three phenotypic classes: (I) Exo-, rough mutants lacking exopolysaccharide; (II) Exos (for "small") which form tiny, compact colonies and synthesize reduced amounts of EPS; and (III) Exoc (for "constitutive"), hypermucoid mutants which overproduce EPS. Hypermucoid strains showed increased resistance to desiccation. All the mutants were able to nodulate, although a significant decrease in infectivity degree and/or competitiveness was found in rough and compact strains. Two mutants proved to be deficient in nitrogen fixation. Complementation analysis with cloned R. meliloti exo genes could not be applied to the study of these Fix- mutants because introduction of plasmids derived from cosmid vector pLAFR1 caused loss of nodulating ability. However, complementation of calcofluor staining and EPS production was observed. Complementation with certain exo genes also caused a marked increase in motility.

  2. 四元数小波和AdaBoost在人脸识别中的应用%Application of quaternion wavelet and AdaBoost in face recognition

    Institute of Scientific and Technical Information of China (English)

    徐永红; 申鸿魁; 赵艳茹; 洪文学

    2011-01-01

    提出一种基于四元数小波变换(QWT)幅值相位表示及AdaBoost的人脸识别方法.四元数小波变换具有近似的移不变特性,可以同时支持1个幅值和3个相位,其中两个相位编码局部图像移动,而第三个相位蕴含纹理信息.方法对人脸图像进行预处理,进行四元数小波变换并计算四元数幅值和相位特征,将这些幅值和相位组合并应用AdaBoost分类器进行分类,以实现人脸图像的最终识别.对Yale、ORL和FERET三个人脸数据库应用此方法的实验结果表明,该方法在识别率上优于AdaBoost和Gabor+AdaBoost.特别是在FERET数据上精度提高更为明显,而且在计算复杂度上QWT特征提取明显低于Gabor特征提取.%This paper proposes a face recognition method based on the Quaternion Wavelet Transform (QWT) magnitude/ phase representation and AdaBoost.This recent transform is a near shift-invariant tight frame representation whose coefficients support a magnitude and three phases.The first two QWT phases encode the shifts of image features in the absolute horizon tal/vertical coordinate system, while the third phase encodes edge orientation mixtures and textural information.The method preprocesses human face images, uses QWT to extract the wavelet coefficients of muIti-orientation, and quaternion amplitude and three phases are computed.These quaternion amplitude and phase features are combined and AdaBoost is used to realize recognition.Experimental resuIts on three face databases including Yale, ORL and FERET show that the method has higher recognition rates than AdaBoost and Gabor+AdaBoost.This method has much better recognizing resuIt on FERET especially. Compared with Gabor wavelet features,QWT features are superior both in accuracy and computation complexity.

  3. System testing of a production Ada (trademark) project: The GRODY study

    Science.gov (United States)

    Seigle, Jeffrey; Esker, Linda; Shi, Ying-Liang

    1990-01-01

    The use of the Ada language and design methodologies that utilize its features has a strong impact on all phases of the software development project lifecycle. At the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC), the Software Engineering Laboratory (SEL) conducted an experiment in parallel development of two flight dynamics systems in FORTRAN and Ada. The teams found some qualitative differences between the system test phases of the two projects. Although planning for system testing and conducting of tests were not generally affected by the use of Ada, the solving of problems found in system testing was generally facilitated by Ada constructs and design methodology. Most problems found in system testing were not due to difficulty with the language or methodology but to lack of experience with the application.

  4. The implementation and use of Ada on distributed systems with high reliability requirements

    Science.gov (United States)

    Knight, J. C.

    1987-01-01

    Performance analysis was begin on the Ada implementations. The goal is to supply the system designer with tools that will allow a rational decision to be made about whether a particular implementation can support a given application early in the design cycle. Primary activities were: analysis of the original approach to recovery in distributed Ada programs using the Advanced Transport Operating System (ATOPS) example; review and assessment of the original approach which was found to be capable of improvement; preparation and presentation of a paper at the 1987 Washington DC Ada Symposium; development of a refined approach to recovery that is presently being applied to the ATOPS example; and design and development of a performance assessment scheme for Ada programs based on a flexible user-driven benchmarking system.

  5. [Isolation of a high hydrogen-producing mutant TB34 generated by transposon insertion and analysis of hydrogen production].

    Science.gov (United States)

    Liu, Hong-Yan; Wang, Guang-Ce; Shi, Liu-Yang; Zhu, Da-Ling

    2012-07-01

    To increase the hydrogen-producing capacity of Pantoea agglomerans BH18, isolated from mangrove sludge, we constructed a stable transposon mutagenesis library of this strain. A Tn7-based transposon was randomly inserted into the genomic DNA. Mutants were screened by kanamycin resistance and identified by amplification of the inserted transposon sequences. A mutant strain TB34 was isolated, whose hydrogen production capacity was significantly improved compared to the wild type strain. In seawater-containing medium supplemented with 10 g x L(-1) glucose and had an initial pH of 7.0, the hydrogen yield (H2/glucose) of the mutant strain was (2.04 +/- 0.04) mol x mol(-1), which was 43% higher than that of the wild type strain. The mutant TB34 showed steady hydrogen production capacity for five consecutive passages. Different carbon sources were tested in the hydrogen production by the mutant TB34 and the results showed that both the mutant strain TB34 and the wild type strain BH18 were able to produce hydrogen on sucrose, glucose and fructose. However, different from the wild type strain, the mutant strain TB34 was also able to produce hydrogen using xylose as substrate, with a hydrogen yield (H2/xylose) of (1.34 +/- 0.09) mol x mol(-1), indicating a broader substrate spectrum in the mutant.

  6. Characterization of a Mutant of Alteromonas aurantia A18 and Its Application in Mariculture

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Mutant J61321 with enhanced siderophore production of Alteromonas aurantia A18 was obtained after a series of chemical-physical mutageneses. It was found that the antibacterial activity against Vibrio anguillarum W-1 and siderophore production of the mutant were higher than those by the original strain A18 which had been used in mariculture. The results of the specific J61321 and the original strain A18, respectively, while the siderophore with catechol group was yielded by strain W-1 (Aibrio anguillarum). Meanwhile, the siderophore yield, antibacterial activity and anti-chelator activity of strain J61321 were higher than those of its parent strain A18.

  7. Ethanol fermentation on glucose/xylose mixture by co-cultivation of restricted glucose catabolite repressed mutants of Pichia stipitis with respiratory deficient mutants of Saccharomyces cerevisiae.

    Science.gov (United States)

    Kordowska-Wiater, Monika; Targoński, Zdzisław

    2002-01-01

    Restricted glucose catabolite repressed mutants of P. stipiti CCY 39501 were selected using UV irradiation. Four mutants were obtained which assimilated glucose slower than the native strain of P. stipitis and the degree of glucose repression was about 2-fold lower for P5-90-133 and P5-200-16 mutants and about 10-fold lower for P5-80-7 and P5-80-35 mutants. P5-80-7 and P5-80-35 produced very small amounts of ethanol from glucose and xylose, whereas P5-90-133 and P5-200-16 fermented sugars at the wild-type level. These two mutants were selected for co-fermentation process with native strain of S. cerevisiae V30 or Ja(a), as well as with their respiratory deficient mutants. During co-culture process of P. stipitis mutants with native strains of S. cerevisiae the ethanol yields obtained ranged from 0.38 to 0.45 g/g, and this alcohol was produced mainly from glucose. But, when also xylose, besides glucose was fermented to ethanol during co-fermentation of both mutant strains, lower yields of ethanol (0.28-0.40 g/g) were obtained.

  8. A-D-A small molecules for solution-processed organic photovoltaic cells.

    Science.gov (United States)

    Ni, Wang; Wan, Xiangjian; Li, Miaomiao; Wang, Yunchuang; Chen, Yongsheng

    2015-03-25

    A-D-A small molecules have drawn more and more attention in solution-processed organic solar cells due to the advantages of a diversity of structures, easy control of energy levels, etc. Recently, a power conversion efficiency of nearly 10% has been achieved through careful material design and device optimization. This feature article reviews recent representative progress in the design and application of A-D-A small molecules in organic photovoltaic cells.

  9. Particular application of methods of AdaBoost and LBP to the problems of computer vision

    OpenAIRE

    Волошин, Микола Володимирович

    2012-01-01

    The application of AdaBoost method and local binary pattern (LBP) method for different spheres of computer vision implementation, such as personality identification and computer iridology, is considered in the article. The goal of the research is to develop error-correcting methods and systems for implements of computer vision and computer iridology, in particular. This article considers the problem of colour spaces, which are used as a filter and as a pre-processing of images. Method of AdaB...

  10. A study of the portability of an Ada system in the software engineering laboratory (SEL)

    Science.gov (United States)

    Jun, Linda O.; Valett, Susan Ray

    1990-01-01

    A particular porting effort is discussed, and various statistics on analyzing the portability of Ada and the total staff months (overall and by phase) required to accomplish the rehost, are given. This effort is compared to past experiments on the rehosting of FORTRAN systems. The discussion includes an analysis of the types of errors encountered during the rehosting, the changes required to rehost the system, experiences with the Alsys IBM Ada compiler, the impediments encountered, and the lessons learned during this study.

  11. Regulation of adenosine deaminase (ADA) on induced mouse experimental autoimmune uveitis (EAU) ?

    OpenAIRE

    Liang, Dongchun; Zuo, Aijun; Zhao, Ronglan; Shao, Hui; Kaplan, Henry J.; Sun, Deming

    2016-01-01

    Adenosine is an important regulator of the immune response and adenosine deaminase (ADA) inhibits this regulatory effect by converting adenosine into functionally inactive molecules. Studies have shown that adenosine receptor (AR) agonists can be either anti- or pro-inflammatory. Clarification of the mechanisms that cause these opposing effects should provide a better guide for therapeutic intervention. In this study, we investigated the effect of ADA on the development of experimental autoim...

  12. Confidence-based multiclass AdaBoost for physical activity monitoring

    OpenAIRE

    Reiss, Attila; Hendeby, Gustaf; Stricker, Didier

    2013-01-01

    Physical activity monitoring has recently become an important topic in wearable computing, motivated by e.g. healthcare applications. However, new benchmark results show that the difficulty of the complex classification problems exceeds the potential of existing classifiers. Therefore, this paper proposes the ConfAdaBoost.M1 algorithm. The proposed algorithm is a variant of the AdaBoost.M1 that incorporates well established ideas for confidence based boosting. The method is compared to the mo...

  13. Secretos de Mutantes

    OpenAIRE

    Marín, Martha; Muñoz, Germán; Serrano, Rafael

    2017-01-01

    Apartándose de enfoques que consideran las culturas juveniles como ‘desviaciones sociales', ‘tribus urbanas' o ‘nuevos movimientos políticos', Secretos de mutantes bucea en culturas juveniles urbanas como la Skinhead, el Punk, el Metal, el Hardcore, el Grunge y el Hip Hop, explorándolas desde un punto de vista inédito: su dimensión de creación, para percibir los cruciales y casi desconocidos procesos que sus miembros llevan a cabo en estos vastos universos de experimentación. Esta obra se nut...

  14. 人egf基因在突变枯草芽孢杆菌WYBS2001中的转化、分泌表达及其产物功能研究%Transforming and Secreting Expression of Human egf in Mutant Strain WYBS2001 of Bacillas and Its Functions

    Institute of Scientific and Technical Information of China (English)

    王关林; 易庆; 方宏筠

    2003-01-01

    通过紫外线突变诱导获得了对感染致病菌具有显著抑菌作用的枯草芽孢杆菌突变株WYBS2001.采用PCR技术人工合成了175 bp的人表皮生长因子(hEGF)的基因片段,并引入Pst Ⅰ、HindⅢ酶切位点、起始密码子及pUS186载体信号肽序列CTTAGA.经DNA测序分析,合成的片段与人egf基因序列完全一致.然后将其克隆至枯草杆菌分泌型质粒载体pUS186上构建成重组质粒pUSE,并转化枯草杆菌突变菌株WYBS2001,获得转人egf基因的枯草杆菌生态工程菌WYBS2001T.RIA检测结果表明,WYBS2001T阳性工程菌培养的上清液中可检测到hEGF,含量为7.6 ng/ml.如果培养液中添加蛋白酶抑制剂可提高hEGF检测量.通过多代的培养仍然能够稳定地分泌表达hEGF.生物学功能实验表明,分泌的hEGF对人K562体外培养细胞的增殖和生长具有明显生物学活性.对烧伤动物模型的功能性实验观察到,WYBS2001T工程菌制剂对动物的烧伤有明显的治疗作用.该研究表明,微生态基因工程菌有很好的应用前景.%Mutant strain WYBS2001 of B. subtilis with strong anti-pathgenic activity was obtained by mutagenic ultraviolet rays. The gene fragment of Human Epidermal Growth Factor(hegf) of 175 bp was synthesized by PCR and the restriction sites Pst Ⅰ and Hind Ⅲ , original code and the signal sequence CTTAGA of secreting vector pUS186 were induced in the fragment. The DNA sequencing result revealed that the synthesized fragment was identical with that of human egf. Then the biological engineering strain WYBS2001T with human egf was obtained by transforming pUSE which was constructed by cloning egf into the secreting plasmid pUS186, into mutant strain WYBS2001. The result of RIA showed that hEGF can be found in the supernatant of the cultures and its content was 7.6 ng/ml. And the content can be increased if the proteinase inhibitor was added into the medium. After several generations' culturing, WYBS2001T positive

  15. PERBANDINGAN EFEK APLIKASI ADAS MANIS SEGAR TUMBUK DAN ADAS MANIS SEGAR DISTELASI PADA MUKOSA MULUT TIKUS WISTAR STRAIN LMR YANG MENGALAMI PERADANGAN (PENELITIAN LABORATORIK

    Directory of Open Access Journals (Sweden)

    Tut Wuri Andajani

    2015-07-01

    Full Text Available Oral mucous inflammation is common in our community. Therefore we need an antiinflammotory medicine with affordable price, relative low adverse effects and easily obtained in our environment. Sweet fennel is a plant that is widely used in our community as a decorating plant, food flavouring and herbal medicine for various diseases. The effectivity for fennel has not been clinically examined. The aim of this research is to examine and compare reactions of both crushed and distilled fennel fruit on inflamed oral mucosa caused by hydrogen peroxide 10%. 14 rats were used and divided into 4 groups and crontrol (6 rats. The received hydrogen peroxide 10% application on vestibulum mucosa for three days to make the inflammation. After that they received crush and distilled fennel. Three days later they were killed and the vestibulum mucosa was excised for microscopic slides. The results showed that the crushed the redness of oral mucosa. The conclusion is fennel could reduce an inflammation and there is nodifference of healing either by crushed or distilled water.

  16. Constructing a working taxonomy of functional Ada software components for real-time embedded system applications

    Science.gov (United States)

    Wallace, Robert

    1986-01-01

    A major impediment to a systematic attack on Ada software reusability is the lack of an effective taxonomy for software component functions. The scope of all possible applications of Ada software is considered too great to allow the practical development of a working taxonomy. Instead, for the purposes herein, the scope of Ada software application is limited to device and subsystem control in real-time embedded systems. A functional approach is taken in constructing the taxonomy tree for identified Ada domain. The use of modular software functions as a starting point fits well with the object oriented programming philosophy of Ada. Examples of the types of functions represented within the working taxonomy are real time kernels, interrupt service routines, synchronization and message passing, data conversion, digital filtering and signal conditioning, and device control. The constructed taxonomy is proposed as a framework from which a need analysis can be performed to reveal voids in current Ada real-time embedded programming efforts for Space Station.

  17. Eficiência e competitividade de variantes espontâneos isolados de estirpes de Bradyrhizobium spp recomendadas para a cultura da soja (Glycine max Effectiveness and competitiveness of spontaneous mutants isolated from Bradyrhizobium spp strains recommended for soybean crop (Glycine max

    Directory of Open Access Journals (Sweden)

    Fabíola Gomes de Carvalho

    2005-12-01

    Full Text Available O cultivo sucessivo de soja inoculada numa mesma área proporcionou a adaptação de uma população de rizóbios, que podem não ser tão eficientes quanto à capacidade de fixação de N2, mas apresentam alta competitividade, dificultando a introdução de novas estirpes mais eficientes. Com a finalidade de avaliar o desempenho simbiótico (eficiência e competitividade de variantes espontâneos isolados de estirpes de B. japonicum (SEMIA 5079 e SEMIA 5080 e B. elkanii (SEMIA 587 e SEMIA 5019, realizou-se um experimento em casa de vegetação onde os variantes foram inoculados isoladamente e em diferentes combinações entre os variantes e uma estirpe comprovadamente mais competitiva (SEMIA 587 ou SEMIA 5019 a partir da adição de inóculos mistos (1/1; v/v no cultivar de soja BR-16. Por meio da avaliação das variáveis analisadas (nodulação, produção de matéria de seca da parte aérea, N total acumulado na parte aérea e ocupação nodular, foi possível constatar que o determinante da maior eficiência em tratamentos co-inoculados não foi a ocupação nodular de determinada estirpe ou variante presente no inóculo, mas, sim, o tipo de interação (sinérgica ou antagônica predominante no tratamento co-inoculado e que é possível selecionar variantes eficientes e competitivos para a cultura da soja a partir de estirpes parentais que já apresentam características desejáveis para utilização em inoculantes comerciais.The continuous cultivation of inoculated soybean in the same area can determine the soil colonization with a rhizobia population presenting low nitrogen fixation effectiveness. This fact can be a problem for the establishment of a more effective population. A greenhouse experiment was carried out to evaluate the symbiotic effectiveness and competitiveness of spontaneous mutants isolated from B. japonicum (SEMIA 5079 and SEMIA 5080 and B. elkanii (SEMIA 587 and SEMIA 5019 strains. The soybean biovar BR 16 was

  18. ECB deacylase mutants

    Science.gov (United States)

    Arnold, Frances H.; Shao, Zhixin; Zhao, Huimin; Giver, Lorraine J.

    2002-01-01

    A method for in vitro mutagenesis and recombination of polynucleotide sequences based on polymerase-catalyzed extension of primer oligonucleotides is disclosed. The method involves priming template polynucleotide(s) with random-sequences or defined-sequence primers to generate a pool of short DNA fragments with a low level of point mutations. The DNA fragments are subjected to denaturization followed by annealing and further enzyme-catalyzed DNA polymerization. This procedure is repeated a sufficient number of times to produce full-length genes which comprise mutants of the original template polynucleotides. These genes can be further amplified by the polymerase chain reaction and cloned into a vector for expression of the encoded proteins.

  19. Ada compiler validation summary report. Certificate number: 891116W1. 10191. Intel Corporation, IPSC/2 Ada, Release 1. 1, IPSC/2 parallel supercomputer, system resource manager host and IPSC/2 parallel supercomputer, CX-1 nodes target

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-16

    This VSR documents the results of the validation testing performed on an Ada compiler. Testing was carried out for the following purposes: To attempt to identify any language constructs supported by the compiler that do not conform to the Ada Standard; To attempt to identify any language constructs not supported by the compiler but required by the Ada Standard; and To determine that the implementation-dependent behavior is allowed by the Ada Standard. Testing of this compiler was conducted by SofTech, Inc. under the direction of he AVF according to procedures established by the Ada Joint Program Office and administered by the Ada Validation Organization (AVO). On-side testing was completed 16 November 1989 at Aloha OR.

  20. Phenotypic characterization and virulence of a sae- agr- mutant of Staphylococcus aureus.

    Science.gov (United States)

    Giraudo, A T; Rampone, H; Calzolari, A; Nagel, R

    1996-02-01

    A sae::Tn551 agr::tetM double mutant was constructed and characterized. The production of several exoproteins (e.g., beta-hemolysin, DNase, and proteases) by this mutant was determined and found to be lower than the already diminished production of either isogenic single mutant sae- or agr-. The double mutant also showed, like the agr- mutant, null production of alpha- and delta-hemolysins and diminished levels of lipase. The reduced levels of many exoproteins in the double mutant as compared with their already diminished levels in either single mutant suggest that there is an additive or synergistic interaction between the two mutations involved, sae- and agr-. However, inactivation of both loci, sae and agr, had a different effect on the two exoproteins that are up regulated in the agr- mutant; thus, coagulase dropped to levels close to the null levels of the sae- parental strain, while extracellular protein A displayed the high levels characteristic of the agr- single mutant. The virulence of the sae- agr- double mutant, determined by intraperitoneal injection in mice, was found to be significantly diminished as compared with that of the sae+ agr+ parental strain or the sae- agr+ single mutant.

  1. Phosphoribosylpyrophosphate synthetase of Escherichia coli, Identification of a mutant enzyme

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne; Nygaard, Per

    1982-01-01

    , stimulated the mutant enzyme. The activity of PRib-PP synthetase in crude extract was higher in the mutant than in the parent. When starved for purines an accumulation of PRib-PP was observed in the parent strain, while the pool decreased in the mutant. During pyrimidine starvation derepression of PRib....... Kinetic analysis of the mutant PRib-PP synthetase revealed an apparent Km for ATP and ribose 5-phosphate of 1.0 mM and 240 μM respectively, compared to 60 μM and 45 μM respectively for the wild-type enzyme. ADP, which inhibits the wild-type enzyme at a concentration of 0.5 mM ribose 5-phosphate...

  2. Phosphoribosylpyrophosphate synthetase of Escherichia coli, Identification of a mutant enzyme

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne; Nygaard, Per

    1982-01-01

    . Kinetic analysis of the mutant PRib-PP synthetase revealed an apparent Km for ATP and ribose 5-phosphate of 1.0 mM and 240 μM respectively, compared to 60 μM and 45 μM respectively for the wild-type enzyme. ADP, which inhibits the wild-type enzyme at a concentration of 0.5 mM ribose 5-phosphate......, stimulated the mutant enzyme. The activity of PRib-PP synthetase in crude extract was higher in the mutant than in the parent. When starved for purines an accumulation of PRib-PP was observed in the parent strain, while the pool decreased in the mutant. During pyrimidine starvation derepression of PRib...

  3. C. elegans and mutants with chronic nicotine exposure as a novel model of cancer phenotype.

    Science.gov (United States)

    Kanteti, Rajani; Dhanasingh, Immanuel; El-Hashani, Essam; Riehm, Jacob J; Stricker, Thomas; Nagy, Stanislav; Zaborin, Alexander; Zaborina, Olga; Biron, David; Alverdy, John C; Im, Hae Kyung; Siddiqui, Shahid; Padilla, Pamela A; Salgia, Ravi

    2016-01-01

    We previously investigated MET and its oncogenic mutants relevant to lung cancer in C. elegans. The inactive orthlogues of the receptor tyrosine kinase Eph and MET, namely vab-1 and RB2088 respectively, the temperature sensitive constitutively active form of KRAS, SD551 (let-60; GA89) and the inactive c-CBL equivalent mutants in sli-1 (PS2728, PS1258, and MT13032) when subjected to chronic exposure of nicotine resulted in a significant loss in egg-laying capacity and fertility. While the vab-1 mutant revealed increased circular motion in response to nicotine, the other mutant strains failed to show any effect. Overall locomotion speed increased with increasing nicotine concentration in all tested mutant strains except in the vab-1 mutants. Moreover, chronic nicotine exposure, in general, upregulated kinases and phosphatases. Taken together, these studies provide evidence in support of C. elegans as initial in vivo model to study nicotine and its effects on oncogenic mutations identified in humans.

  4. Ada Compiler Validation Summary Report. Certificate Number: 891019W1. 10178, Hewlett Packard Company HP 9000 Series 800 Ada Compiler, Version 4.35 HP 9000 Series 800 Model 850. Completion of On-Site Testing: 19 October 1989

    Science.gov (United States)

    1989-10-19

    1985, the Commerce Department issued Part’ 379 Technical Data of the Export Administration specifically listing Ada Programming Support Environments...maintaining a uniform process for validation of Ada compilers. The AVO provides administrative and technical support for Ada validations to ensure...unused trailing bytes will not be appended. The principie use for the RECORD UNIT parameter is in reading and writing external files that are in

  5. Ada Compiler Validation Summary Report: Certificate Number: 910918S1.11217, NEC Corporation, NEC Ada Compiler System for EWS-UX/V to V70/RX-UX832, Version 1.0 EWS 4800/60 = MV4000

    Science.gov (United States)

    1991-01-01

    8217 The Ada~ System generator 30 I OPTIONS AND COMMANDS OF THE PLU 1 Options and Commands of The PLU The Program Library Utility (PLU) of NEC Ada...myprogram 4 OPTIONS FOR THE ADA SYSTEM GENERATOR 30 The linker will include the code in Obj ectFile. o in the linkage of the program "myprogram". This...program presumably features a program interface to some routines appearing in the ObjectFile. 4 Options for The Ada System generator asgv70 is a

  6. Isolation of a Rhodobacter capsulatus mutant that lacks c-type cytochromes and excretes porphyrins.

    OpenAIRE

    Biel, S W; Biel, A J

    1990-01-01

    A Rhodobacter capsulatus mutant lacking cytochrome oxidase activity was isolated by Tn5 mutagenesis. Difference spectroscopy of crude extracts and extracted c-type cytochromes demonstrated that this mutant completely lacked all c-type cytochromes. The strain did, however, synthesize normal amounts of b-type cytochromes and nonheme iron. This mutant also excreted large amounts of coproporphyrin and protoporphyrin and synthesized reduced amounts of bacteriochlorophyll, suggesting a link between...

  7. Investigation into the resistance of lactoperoxidase tolerant Escherichia coli mutants to different forms of oxidative stress.

    Science.gov (United States)

    De Spiegeleer, Philipp; Vanoirbeek, Kristof; Lietaert, Annelies; Sermon, Jan; Aertsen, Abram; Michiels, Chris W

    2005-11-15

    Six lactoperoxidase tolerant Escherichia coli transposon mutants isolated and characterized in an earlier study, and some newly constructed double mutants, were subjected to peroxide, superoxide and hypochlorite stress, and their inactivation was compared to that of the wild type strain MG1655. Knock out mutants of waaQ and waaO, which owed their lactoperoxidase tolerance to an impaired outer membrane permeability due to a reduced porin content, also exhibited higher resistance to hypochlorite, as did a knock-out strain of lrp, encoding a regulatory protein affecting a wide range of cellular functions. Unlike the outer membrane mutants however, the lrp strain was also more resistant to t-butyl hydroperoxide, but more susceptible to the superoxide generating compound plumbagin. Finally, a lactoperoxidase tolerant knock-out strain of ulaA, involved in ascorbic acid uptake, did not show resistance to any of the other oxidants. The possible modes of action of these different oxidants are discussed.

  8. Isolation of Rhizobium phaseoli Tn5-induced mutants with altered expression of cytochrome terminal oxidases o and aa3.

    Science.gov (United States)

    Soberón, M; Membrillo-Hernández, J; Aguilar, G R; Sánchez, F

    1990-01-01

    Two Rhizobium phaseoli mutants affected in cytochrome expression were obtained by Tn5-mob mutagenesis of the wild-type strain (CE3). Mutant strain CFN031 expressed sevenfold less cytochrome o in culture, expressed cytochrome aa3 under microaerophilic culture conditions, in contrast to strain CE3, and was affected in its vegetative growth properties and proliferation inside plant host cells. Mutant CFN037 expressed cytochrome aa3 under microaerophilic culture conditions, while bacteroid development and nitrogen fixation occurred earlier than in strain CE3. Images FIG. 2 PMID:2155209

  9. Direct Selection of Clostridium acetobutylicum Fermentation Mutants by a Proton Suicide Method

    OpenAIRE

    Cueto, Pablo H.; Méndez, Beatriz S.

    1990-01-01

    Clostridium acetobutylicum ATCC 10132 mutants altered in acetic acid synthesis or in the shift to solventogenesis were directly selected by a proton suicide method after mutagenic treatment, by using bromide and bromate as selective agents. The mutants were characterized according to their solvent and acid production. On the selection plates they differed in colony phenotype from the parent strain.

  10. Platelet aggregation and serum adenosine deaminase (ADA) activity in pregnancy associated with diabetes, hypertension and HIV.

    Science.gov (United States)

    Leal, Claudio A M; Leal, Daniela B R; Adefegha, Stephen A; Morsch, Vera M; da Silva, José E P; Rezer, João F P; Schrekker, Clarissa M L; Abdalla, Faida H; Schetinger, Maria R C

    2016-07-01

    Platelet aggregation and adenosine deaminase (ADA) activity were evaluated in pregnant women living with some disease conditions including hypertension, diabetes mellitus and human immunodeficiency virus infection. The subject population is consisted of 15 non-pregnant healthy women [control group (CG)], 15 women with normal pregnancy (NP), 7 women with hypertensive pregnancy (HP), 10 women with gestational diabetes mellitus (GDM) and 12 women with human immunodeficiency virus-infected pregnancy (HIP) groups. The aggregation of platelets was checked using an optical aggregometer, and serum ADA activity was determined using the colorimetric method. After the addition of 5 µM of agonist adenosine diphosphate, the percentage of platelet aggregation was significantly (p < 0·05) increased in NP, HP, GDM and HIP groups when compared with the CG, while the addition of 10 µM of the same agonist caused significant (p < 0·05) elevations in HP, GDM and HIP groups when compared with CG. Furthermore, ADA activity was significantly (p < 0·05) enhanced in NP, HP, GDM and HIP groups when compared with CG. In this study, the increased platelet aggregation and ADA activity in pregnancy and pregnancy-associated diseases suggest that platelet aggregation and ADA activity could serve as peripheral markers for the development of effective therapy in the maintenance of homeostasis and some inflammatory process in these pathophysiological conditions. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Cell surface and transcriptional characterization of human adipose-derived adherent stromal (hADAS) cells.

    Science.gov (United States)

    Katz, Adam J; Tholpady, Ashok; Tholpady, Sunil S; Shang, Hulan; Ogle, Roy C

    2005-03-01

    Adult human subcutaneous adipose tissue contains cells with intriguing multilineage developmental plasticity, much like marrow-derived mesenchymal stem cells. Putative stem or progenitor cells from fat have been given many different names in the literature, reflecting an early and evolving consensus regarding their phenotypic characterization. The study reported here used microarrays to evaluate over 170 genes relating to angiogenesis and extracellular matrix in undifferentiated, early-passage human adipose-derived adherent stromal (hADAS) cells isolated from three separate donors. The hADAS populations unanimously transcribed 66% of the screened genes, and 83% were transcribed by at least two of the three populations. The most highly transcribed genes relate to functional groupings such as cell adhesion, matrix proteins, growth factors and receptors, and proteases. The transcriptome of hADAS cells demonstrated by this work reveals many similarities to published profiles of bone marrow mesenchymal stem cells (MSCs). In addition, flow analysis of over 24 hADAS cell surface proteins (n = 7 donors) both confirms and expands on the existing literature and reveals strong intergroup correlation, despite an inconsistent nomenclature and the lack of standardized protocols for cell isolation and culture. Finally, based on flow analysis and reverse transcription polymerase chain reaction studies, our results suggest that hADAS cells do not express several proteins that are implicated as markers of "stemness" in other stem cell populations, including telomerase, CD133, and the membrane transporter ABCG2.

  12. The inclusion of ADA-SCID in expanded newborn screening by tandem mass spectrometry.

    Science.gov (United States)

    la Marca, Giancarlo; Giocaliere, Elisa; Malvagia, Sabrina; Funghini, Silvia; Ombrone, Daniela; Della Bona, Maria Luisa; Canessa, Clementina; Lippi, Francesca; Romano, Francesca; Guerrini, Renzo; Resti, Massimo; Azzari, Chiara

    2014-01-01

    Severe combined immunodeficiency due to adenosine-deaminase defect (ADA-SCID) is usually deadly in childhood because of severe recurrent infections. When clinical diagnosis is done, permanent damages due to infections or metabolite accumulation are often present. Gene therapy, bone marrow transplantation or enzyme replacement therapy may be effective if started early. The aim of this study was to set-up a robust method suitable for screening with a minimized preparation process and with inexpensive running costs, for diagnosing ADA-SCID by tandem mass spectrometry. ADA-SCID satisfies all the criteria for inclusion in a newborn screening program. We describe a protocol revised to incorporate adenosine and 2-deoxyadenosine testing into an expanded newborn screening program. We assessed the effectiveness of this approach testing dried blood spots from 4 genetically confirmed early-onset and 5 delayed-onset ADA-SCID patients. Reference values were established on 50,000 healthy newborns (deoxyadenosine <0.09μmol/L, adenosine <1.61μmol/L). We also developed a second tier test to distinguish true positives from false positives and improve the positive predictive value of an initial abnormal result. In the first 18 months, the pilot project has identified a newborn with a genetically confirmed defect in adenosine deaminase (ADA) gene. The results show that the method having great simplicity, low cost and low process preparations can be fully applicable to a mass screening program.

  13. Pegademase bovine (PEG-ADA for the treatment of infants and children with severe combined immunodeficiency (SCID

    Directory of Open Access Journals (Sweden)

    Claire Booth

    2009-06-01

    Full Text Available Claire Booth1,2, H Bobby Gaspar1,21Centre for Immunodeficiency, Molecular Immunology Unit, UCL Institute of Child Health, London, UK; 2Dept of Clinical Immunology, Great Ormond Street Hospital NHS Trust, London, UKAbstract: Adenosine deaminase deficiency (ADA is a rare, inherited disorder of purine metabolism characterized by immunodeficiency, failure to thrive and metabolic abnormalities. A lack of the enzyme ADA allows accumulation of toxic metabolites causing defects of both cell mediated and humoral immunity leading to ADA severe combined immune deficiency (SCID, a condition that can be fatal in early infancy if left untreated. Hematopoietic stem cell transplant is curative but is dependent on a good donor match. Other therapeutic options include enzyme replacement therapy (ERT with pegademase bovine (PEG-ADA and more recently gene therapy. PEG-ADA has been used in over 150 patients worldwide and has allowed stabilization of patients awaiting more definitive treatment with hematopoietic stem cell transplant. It affords both metabolic detoxification and protective immune function with patients remaining clinically well, but immune reconstitution is often suboptimal and may not be long lived. We discuss the pharmacokinetics, immune reconstitution, effects on systemic disease and side effects of treatment with PEG-ADA. We also review the long-term outcome of patients receiving ERT and discuss the role of PEG-ADA in the management of infants and children with ADA-SCID, alongside other therapeutic options.Keywords: adenosine deaminase deficiency, PEG-ADA, enzyme replacement therapy, severe combined immune deficiency (SCID

  14. Construction and characterization of a glycoprotein E deletion mutant of bovine herpesvirus type 1.2 strain isolated in Brazil Construção e caracterização de uma amostra de BoHV-1.2 isolada no Brasil com uma deleção no gene da glicoproteína E

    Directory of Open Access Journals (Sweden)

    Ana C. Franco

    2002-09-01

    Full Text Available This paper describes the construction and characterization of a Brazilian strain of bovine herpesvirus type 1.2a (BoHV-1.2a with a deletion of the glycoprotein E (gE gene. The deletion was introduced by co-transfection of a deletion fragment containing the 5´and 3´gE flanking regions and genomic DNA of wild type BoHV-1 into bovine cells. Isolation of gE deletion mutant was performed by immunoperoxidase staining with an anti-gE monoclonal antibody. Viral clones were plaque purified and further examined by restriction endonuclesase digestion and Southern blot hybridization. This gE deletion mutant will be evaluated as a vaccinal virus, in order to determine its potential use for a differential vaccine.Este artigo descreve a construção e caracterização de uma amostra de um herpesvírus bovino tipo 1.2a (BoHV-1.2a que apresenta uma deleção na região genômica que codifica a glicoproteína E (gE. A deleção gênica foi induzida através da co-transfecção de um fragmento de deleção, contendo as regiões 5´e 3´flanqueadoras da gE, com o DNA viral intacto de uma amostra viral isolada de um animal que apresentava doença respiratória. O isolamento do vírus gE negativo (gE- foi realizado com auxílio da técnica de imunoperoxidase em que foi utilizado como anticorpo primário um anticorpo monoclonal anti-gE. O vírus gE- foi purificado e o DNA isolado desta amostra foi examinado através das técnicas de análise por enzimas de restrição e "Southern blot". Esta amostra gE- será avaliada como candidata para compor uma vacina diferencial contra a rinotraqueíte infecciosa dos bovinos.

  15. Characterization of a mutant glucose isomerase from Thermoanaerobacterium saccharolyticum.

    Science.gov (United States)

    Xu, Heng; Shen, Dong; Wu, Xue-Qiang; Liu, Zhi-Wei; Yang, Qi-He

    2014-10-01

    A series of site-directed mutant glucose isomerase at tryptophan 139 from Thermoanaerobacterium saccharolyticum strain B6A were purified to gel electrophoretic homogeneity, and the biochemical properties were determined. W139F mutation is the most efficient mutant derivative with a tenfold increase in its catalytic efficiency toward glucose compared with the native GI. With a maximal activity at 80 °C of 59.58 U/mg on glucose, this mutant derivative is the most active type ever reported. The enzyme activity was maximal at 90 °C and like other glucose isomerase, this mutant enzyme required Co(2+) or Mg(2+) for enzyme activity and thermal stability (stable for 20 h at 80 °C in the absence of substrate). Its optimum pH was around 7.0, and it had 86 % of its maximum activity at pH 6.0 incubated for 12 h at 60 °C. This enzyme was determined as thermostable and weak-acid stable. These findings indicated that the mutant GI W139F from T. saccharolyticum strain B6A is appropriate for use as a potential candidate for high-fructose corn syrup producing enzyme.

  16. Survival of Brucella abortus aqpX mutant in fresh and ripened cheeses.

    Science.gov (United States)

    Santiago-Rodríguez, María Del Rosario; Díaz-Aparicio, Efrén; Arellano-Reynoso, Beatriz; García-Lobo, Juan M; Gimeno, Miquel; Palomares-Reséndiz, Erika G; Hernández-Castro, Rigoberto

    2015-02-01

    The objective of this work was to evaluate the survival of a Brucella abortus aqpX mutant during the elaboration and conservation of fresh and ripened cheeses at 4 °C and 24 °C. The pH values and water activity were monitored for each type of cheese. The fresh cheese was elaborated with raw milk inoculated with 6×10⁸ colony-forming units (CFU)/mL each of parental and mutant strain. Ripening cheeses were elaborated with both raw and pasteurized milk and inoculated with 12×10⁸ CFU/mL each of parental and mutant strains. In fresh cheese, survival was observed during elaboration and conservation for 7 days at 4 °C in mutant and parental strains. The number of survivors of the mutant strain was 10 times lower compared with the parental strain at pH 5 and a(w) of 0.930. In the cheese elaborated with raw milk and ripened at 24 °C, both strains survived until day 17 at pH 4.0 and a(w) of 0.89. However, when the cheese was elaborated with pasteurized milk, the parental strain survived until day 31 of ripening, and the mutant strain survived 24 days at pH 4 and a(w) of 0.886. The survival of the mutant strain showed a diminution of one logarithm during elaboration and ripening of cheese as compared with the parental strain. When the cheese was elaborated with raw milk and ripened at 4 °C, survival of the parental strain was 24 days, whereas the mutant strain survived only 17 days (pH 5 and a(w) 0.90). Regarding the cheese elaborated with pasteurized milk and maturated at 4 °C, both strains survived 31 days (pH 5 and a(w) 0.90), with the same survival diminution during elaboration and ripening. Our results show that in both types of cheese, the mutated aqpX strain survived 10 times less than the parental strain, which shows that the aqpX gene can be related to the survival of Brucella abortus in this type of cheese.

  17. Isolation and characterization of Escherichia coli mutants lacking inducible cyanase.

    Science.gov (United States)

    Guilloton, M; Karst, F

    1987-03-01

    To determine the physiological role of cyanate aminohydrolase (cyanase, EC 3.5.5.3) in bacteria, mutants of Escherichia coli K12 devoid of this inducible activity were isolated and their properties investigated. Five independent mutations were localized next to lac; three of them lay between lacY and codA. Thus cyanase activity could depend on the integrity of one gene or set of clustered genes; we propose for this locus the symbol cnt. Growth of the mutant stains was more sensitive to cyanate than growth of wild-type strains. This difference was noticeable in synthetic medium in the presence of low concentrations of cyanate (less than or equal to 1 mM). Higher concentrations inhibited growth of both wild-type and mutant strains. Urea in aqueous solutions dissociates slowly into ammonium cyanate. Accordingly wild-type strains were able to grow on a synthetic medium containing 0.5 M-urea whereas mutants lacking cyanase were not. We conclude that cyanase could play a role in destroying exogenous cyanate originating from the dissociation of carbamoyl compounds such as urea; alternatively cyanate might constitute a convenient nitrogen source for bacteria able to synthesize cyanase in an inducible way.

  18. AdaBoost人脸检测算法在DSP上的移植与优化%Transplantation and optimization of AdaBoost face detection algorithm on DSP

    Institute of Scientific and Technical Information of China (English)

    朱明; 陆小锋; 陆亨立; 李莹娇; 张东升

    2014-01-01

    将Viola等人提出的AdaBoost人脸检测算法由PC机移植到TMS320DM642嵌入式平台,采用EMCV (Embedded Computer Vision Library)移植方案,将PC平台的OpenCV(Open Source Computer Vision Library)视觉库中有关AdaBoost算法的模块修改使之适应嵌入式DSP平台。该移植工作主要解决了OpenCV在嵌入式平台的不兼容问题以及不同体系架构的编译器环境和库文件导致的编译和链接错误。优化工作在TI的编译器CCS中进行,在编译器平台下进行C语言的项目及程序优化,并进行了大量实验数据的对比,给出了优化的方案,对实现系统的实时性有指导性作用。%This paper transplants the AdaBoost algorithm proposed by Viola from PC platform to TMS320DM642 platform. The transplantation solves the compile problem caused by the difference between PC and DSP platform. The algorithm optimization is proceeding in CCS compiler which is provided by Texas Instruments. The paper optimizes the AdaBoost algorithm by the optimization of C code and the project settings, and a lot of experiments are done to give out the optimi-zation solution. It plays a guiding role in the implementation of real-time feature in embedded DM642 platform.

  19. Improved AdaBoost ensemble approach based on loss function%基于损失函数的AdaBoost改进算法

    Institute of Scientific and Technical Information of China (English)

    雷蕾; 王晓丹

    2012-01-01

    针对AdaBoost集成时难分样本权重扩张导致训练样本在更新时分布失衡的问题,提出一种基于正负类样本损失函数(LF)的权重更新策略.权重的调整不仅与训练误差有关,还考虑到基分类器对不同类别样本的正确分类能力,从而避免训练样本过度集中于某一类的异常现象.实验结果表明,基于LF的AdaBoost能在提高收敛性能的情况下,提高算法精度,克服样本分布失衡问题.偏差方差分析的结果显示,该算法在改善偏差的情况下,能有效地减小错误率中的方差成分,提高集成的泛化能力.%As to the issue that the weight expansion for hardest samples can cause imbalance when updating the training sample in AdaBoost algorithm, an improved approach based on the Loss Function (LF) of the different patterns, namely, LF-AdaBoost, was proposed. The weight tuning was affected not only by the training error, but the performance of base classifiers for different classes, thus avoiding the excessive concentration phenomenon. The results based on UCI data sets and different base classifiers have shown that the approach can improve the speed of convergence and overcome the imbalance,as well as promote the generalization ability of ensemble classifier.

  20. The role of transcriptional coactivator ADA2b in Arabidopsis abiotic stress responses.

    Science.gov (United States)

    Vlachonasios, Konstantinos E; Kaldis, Athanasios; Nikoloudi, Adriana; Tsementzi, Despoina

    2011-10-01

    Plant growth and crop production can be greatly affected by common environmental stresses such as drought, high salinity and low temperatures. Gene expression is affected by several abiotic stresses. Stress-inducible genes are regulated by transcription factors and epigenetic mechanisms such as histone modifications. In this Mini-Review, we have explored the role of transcriptional adaptor ADA2b in Arabidopsis responses to abiotic stress. ADA2b is required for the expression of genes involved in abiotic stress either by controlling H3 and H4 acetylation in the case of salt stress or affecting nucleosome occupancy in low temperatures response.

  1. Psychometric evaluation of ADAS-Cog and NTB for measuring drug response.

    Science.gov (United States)

    Karin, A; Hannesdottir, K; Jaeger, J; Annas, P; Segerdahl, M; Karlsson, P; Sjögren, N; von Rosen, T; Miller, F

    2014-02-01

    To conduct a psychometric analysis to determine the adequacy of instruments that measure cognition in Alzheimer's disease trials. Both the Alzheimer's Disease Assessment Scale - Cognition (ADAS-Cog) and the Neuropsychological Test Battery (NTB) are validated outcome measures for clinical trials in Alzheimer's disease and are approved also for regulatory purposes. However, it is not clear how comparable they are in measuring cognitive function. In fact, many recent trials in Alzheimer's disease patients have failed and it has been questioned if ADAS-Cog still is a sensitive measure. The present paper examines the psychometric properties of ADAS-Cog and NTB, based on a post hoc analysis of data from a clinical trial (NCT01024660), which was conducted by AstraZeneca, in mild-to-moderate Alzheimer's disease (AD) patients, with a Mini Mental State Examination (MMSE) Total score 16-24. Acceptability, reliability, different types of validity and ability to detect change were assessed using relevant statistical methods. Total scores of both tests, as well as separate domains of both tests, including the Wechsler Memory Scale (WMS), Rey Auditory Verbal Learning Test (RAVLT) and Delis-Kaplan Executive Function System (D-KEFS) Verbal Fluency Condition, were analyzed. Overall, NTB performed well, with acceptable reliability and ability to detect change, while ADAS-Cog had insufficient psychometric properties, including ceiling effects in 8 out of a total of 11 ADAS-Cog items in mild AD patients, as well as low test-retest reliability in some of the items. Based on a direct comparison on the same patient sample, we see advantages of the NTB compared with the ADAS-Cog for the evaluation of cognitive function in the population of mild-to-moderate AD patients. The results suggest that not all of ADAS-Cog items are relevant for both mild and moderate AD population. This validation study demonstrates satisfactory psychometric properties of the NTB, while ADAS-Cog was found to be

  2. Integrating Object-Oriented Programming and Protected Objects in Ada 95

    OpenAIRE

    Wellings, Andy J.; Johnson, Bob; Sanden, Bo; Kienzle, Jörg; Wolf, Thomas; Michell, Stephen

    2000-01-01

    Integrating concurrent and object-oriented programming as been an active research topic since the late 1980s. There is now a plethora of methods for achieving this integration. The majority of approaches have taken a sequential object-oriented language and made it concurrent. A few approaches have taken a concurrent language and made it object-oriented. The most important of this latter case is the Ada 95 language which is an extension to the object-based concurrent programming language Ada 8...

  3. 雄甾-4-烯-3,17-二酮11α羟化突变株Metarhizium anisopliae M28-203的代谢调控%Metabolic regulation of androst-4-ene-3,17-dione 11α-hydroxylation mutant strain Metarhizium anisopliae M28-203

    Institute of Scientific and Technical Information of China (English)

    叶丽; 周珮; 冯美卿

    2011-01-01

    目的 从营养代谢调控和转化条件控制两个方面入手提高雄甾-4-烯-3,17-二酮(androst-4-ene-3,17-dione,AD)11α羟化突变株Metarhizium anisopliae M28-203转化效率.方法 通过正交试验确定发酵培养基配方,对影响转化的一系列因素如:pH、发酵时间、通气量、底物投料量及溶解性、细胞通透性进行控制,考察以上因素对羟化反应的影响,确定最佳转化条件.结果 该突变株培养基最佳配方为葡萄糖30 g/L、玉米浆20 g/L、蚕蛹粉5 g/L、硫酸铵2.5 g/L、磷酸氢二钾1 g/L、硫酸镁0.5 g/L和硫酸亚铁0.02 g/L.在pH 6.0~6.5、菌龄48~60 h、250 mL摇瓶装液量为30和40 mL、转化时间72 h时能取得最佳转化效果.在底物投料量为2 mg/mL时,采用4%无水乙醇溶解底物或加入0.75 mg/mL Tween 80均有利于羟化反应,在以上优化条件下转化率分别达到62.5%和66.8%.结论 突变株Metarhizium anisopliae M28-203能有效地在AD上引入11α羟基,为工业生产依普利酮及其他甾体药物提供关键中间体.%Objective To improve the transformation efficiency of androst-4-ene-3, 17-dione (AD) llα-hydroxylation mutant strain Metarhizium anisopliae M28-203 through regulations of nutrition metabolism and biotransformation conditions. Methods The optimal fermentation culture was determined by orthogonal test. The effects of pH, fermentation time, air flow, substrate addition method and substrate concentration on hydroxylation were investigated and the optimal transformation condition was constructed. Results The optimal fermentation culture contained glucose 30 g/L, corn steep 20 g/L, silkworm chrysalis powder 5 g/L, (NH4)2SO4 2.5 g/L, K2HPO4 1 g/L, MgSO4 0.5 g/L and FeSO4 0.02 g/L. The optimal transformation condition was pH 6.0 - 6.5, 48 - 60 h mycelium age, 30 and 40 mL medium volume in 250 mL shake flask and 72 hour transformation time. Both 4% ethanol and 0.75 mg/mL Tween 80 were helpful for substrate solubility, and then

  4. Comparative study of the mutant prevention concentrations of moxifloxacin, levofloxacin, and gemifloxacin against pneumococci.

    Science.gov (United States)

    Credito, Kim; Kosowska-Shick, Klaudia; McGhee, Pamela; Pankuch, Glenn A; Appelbaum, Peter C

    2010-02-01

    We tested the propensity of three quinolones to select for resistant Streptococcus pneumoniae mutants by determining the mutant prevention concentration (MPC) against 100 clinical strains, some of which harbored mutations in type II topoisomerases. Compared with levofloxacin and gemifloxacin, moxifloxacin had the lowest number of strains with MPCs above the susceptibility breakpoint (P<0.001), thus representing a lower selective pressure for proliferation of resistant mutants. Only moxifloxacin gave a 50% MPC (MPC50) value (1 microg/ml) within the susceptible range.

  5. Comparative Study of the Mutant Prevention Concentrations of Moxifloxacin, Levofloxacin, and Gemifloxacin against Pneumococci▿ †

    Science.gov (United States)

    Credito, Kim; Kosowska-Shick, Klaudia; McGhee, Pamela; Pankuch, Glenn A.; Appelbaum, Peter C.

    2010-01-01

    We tested the propensity of three quinolones to select for resistant Streptococcus pneumoniae mutants by determining the mutant prevention concentration (MPC) against 100 clinical strains, some of which harbored mutations in type II topoisomerases. Compared with levofloxacin and gemifloxacin, moxifloxacin had the lowest number of strains with MPCs above the susceptibility breakpoint (P < 0.001), thus representing a lower selective pressure for proliferation of resistant mutants. Only moxifloxacin gave a 50% MPC (MPC50) value (1 μg/ml) within the susceptible range. PMID:20008781

  6. Isolation and characterization of stable mutants of Streptomyces peucetius defective in daunorubicin biosynthesis

    Indian Academy of Sciences (India)

    K. S. Vetrivel; K. Dharmalingam

    2001-04-01

    Daunorubicin and its derivative doxorubicin are antitumour anthracycline antibiotics produced by Streptomyces peucetius. In this study we report isolation of stable mutants of S. peucetius blocked in different steps of the daunorubicin biosynthesis pathway. Mutants were screened on the basis of colony colour since producer strains are distinctively coloured on agar plates. Different mutants showed accumulation of aklaviketone, -rhodomycinone, maggiemycin or 13-dihydrocarminomycin in their culture filtrates. These results indicate that the mutations in these isolates affect steps catalysed by dnrE (mutants SPAK and SPMAG), dnrS (SPFS and SPRHO) and doxA (SPDHC) gene products.

  7. Alterations in the brain adenosine metabolism cause behavioral and neurological impairment in ADA-deficient mice and patients

    Science.gov (United States)

    Sauer, Aisha V.; Hernandez, Raisa Jofra; Fumagalli, Francesca; Bianchi, Veronica; Poliani, Pietro L.; Dallatomasina, Chiara; Riboni, Elisa; Politi, Letterio S.; Tabucchi, Antonella; Carlucci, Filippo; Casiraghi, Miriam; Carriglio, Nicola; Cominelli, Manuela; Forcellini, Carlo Alberto; Barzaghi, Federica; Ferrua, Francesca; Minicucci, Fabio; Medaglini, Stefania; Leocani, Letizia; la Marca, Giancarlo; Notarangelo, Lucia D.; Azzari, Chiara; Comi, Giancarlo; Baldoli, Cristina; Canale, Sabrina; Sessa, Maria; D’Adamo, Patrizia; Aiuti, Alessandro

    2017-01-01

    Adenosine Deaminase (ADA) deficiency is an autosomal recessive variant of severe combined immunodeficiency (SCID) caused by systemic accumulation of ADA substrates. Neurological and behavioral abnormalities observed in ADA-SCID patients surviving after stem cell transplantation or gene therapy represent an unresolved enigma in the field. We found significant neurological and cognitive alterations in untreated ADA-SCID patients as well as in two groups of patients after short- and long-term enzyme replacement therapy with PEG-ADA. These included motor dysfunction, EEG alterations, sensorineural hypoacusia, white matter and ventricular alterations in MRI as well as a low mental development index or IQ. Ada-deficient mice were significantly less active and showed anxiety-like behavior. Molecular and metabolic analyses showed that this phenotype coincides with metabolic alterations and aberrant adenosine receptor signaling. PEG-ADA treatment corrected metabolic adenosine-based alterations, but not cellular and signaling defects, indicating an intrinsic nature of the neurological and behavioral phenotype in ADA deficiency. PMID:28074903

  8. Pegademase bovine (PEG-ADA) for the treatment of infants and children with severe combined immunodeficiency (SCID)

    Science.gov (United States)

    Booth, Claire; Gaspar, H Bobby

    2009-01-01

    Adenosine deaminase deficiency (ADA) is a rare, inherited disorder of purine metabolism characterized by immunodeficiency, failure to thrive and metabolic abnormalities. A lack of the enzyme ADA allows accumulation of toxic metabolites causing defects of both cell mediated and humoral immunity leading to ADA severe combined immune deficiency (SCID), a condition that can be fatal in early infancy if left untreated. Hematopoietic stem cell transplant is curative but is dependent on a good donor match. Other therapeutic options include enzyme replacement therapy (ERT) with pegademase bovine (PEG-ADA) and more recently gene therapy. PEG-ADA has been used in over 150 patients worldwide and has allowed stabilization of patients awaiting more definitive treatment with hematopoietic stem cell transplant. It affords both metabolic detoxification and protective immune function with patients remaining clinically well, but immune reconstitution is often suboptimal and may not be long lived. We discuss the pharmacokinetics, immune reconstitution, effects on systemic disease and side effects of treatment with PEG-ADA. We also review the long-term outcome of patients receiving ERT and discuss the role of PEG-ADA in the management of infants and children with ADA-SCID, alongside other therapeutic options. PMID:19707420

  9. The isolation of Staphylococcus aureus tea tree oil-reduced susceptibility mutants.

    Science.gov (United States)

    Cuaron, Jesus A; Dulal, Santosh; Cooke, Peter H; Torres, Nathanial J; Gustafson, John E

    2014-08-01

    Tea tree oil (TTO)-reduced susceptibility (TTORS) mutants of two Staphylococcus aureus laboratory strains were isolated utilizing TTO gradient plates. Attempts to isolate TTORS mutants employing agar plates containing single TTO concentrations failed. All TTORS mutants demonstrated a small colony variant (SCV) phenotype and produced cells with a smaller diameter, as determined by scanning electron microscopy. The addition of SCV auxotrophic supplements to media did not lead to an increase in TTORS mutant colony size. Revertants were also isolated from the TTORS mutants following growth in drug-free media, and all revertant strains demonstrated phenotypes similar to their respective parent strains. Transmission electron microscopy revealed that an SH1000 TTORS mutant demonstrated a thinner cell wall and novel septal invaginations compared with parent strain SH1000. In addition, comparative genomic sequencing did not reveal any mutations in an SH1000 TTORS mutant previously linked to well-characterized SCV genotypes. This study demonstrates that TTO can select for a unique SCV phenotype.

  10. Isolation and characterization of selenate resistant mutants of Acremonium chrysogenum

    Directory of Open Access Journals (Sweden)

    Airton Vialta

    1999-01-01

    Full Text Available Mutants unable to convert exogenous sulfate to sulfite were isolated using the toxic analogue selenate. Three of twenty-eight isolated mutants were chromate sensitive. They showed a possible lesion in the gene that codes the ATP sulfurylase. The others were chromate resistant, and probably had a lesion in one or both of the genes that code the sulfate permease. Methionine increased the resistance levels to selenate. In addition, the frequency of spontaneous mutants obtained in a medium containing methionine was higher (between 2.4 x 10-6 and 18.0 x 10-6 than that obtained using a medium without any intentional source of sulfur (between 0.7 x 10-6 and 5.0 x 10-6. The original strain, as well as the mutants, were able to grow in a sulfur-free liquid medium even after 4 consecutive inoculation procedures. These results indicated the existence of sulfur traces in the medium and/or an efficient intracellular storage system. There was no significant difference between cephalosporin C production in mutants and the original strain.Mutantes incapazes de converter o sulfato extracelular em sulfito foram isolados utilizando o análogo tóxico selenato. De 28 mutantes isolados, apenas 3 foram sensíveis ao cromato, provavelmente apresentando lesão no gene que codifica a ATP sulfurilase. Os demais foram resistentes ao cromato e devem conter lesão no gene sB ou também no gene sC. A metionina elevou os níveis de resistência ao selenato e a freqüência de mutantes espontâneos obtida em meio contendo este aminoácido foi maior (entre 2,42 x 10-6 e 18,04 x 10-6 do que a obtida no meio sem a adição de qualquer fonte intencional de enxofre (entre 0,71 x 10-6 e 5,0 x 10-6. A linhagem original e os mutantes foram capazes de crescer, mesmo depois de quatro etapas de inóculo, fato que pode ser explicado pela existência de traços do referido elemento no meio e/ou a presença de um sistema eficiente de estocagem intracelular. A produção de cefalosporina C

  11. A Plan for Collecting Ada Software Development Cost, Schedule, and Environment Data.

    Science.gov (United States)

    1987-04-02

    person-weeks is the minimum training time. This time includes teaching a methodology adapted to Ada and 50 percent hands-on experiments under the...level." He felt translation of existing programs was an excellent way to bring pro- grammers up to speed. The more mathematical functions in the program

  12. Automatic player detection and recognition in images using AdaBoost

    NARCIS (Netherlands)

    Mahmood, Zahid; Ali, Tauseef; Khattak, Shadid

    2012-01-01

    In this work we developed an augmented reality sports broadcasting application for enhanced end-user experience. The proposed system consists of three major steps. In the first step each player is detected using AdaBoost Algorithm. In second step, same algorithm is used to detect face in each player

  13. 61 FR 11863 - Vehicle Management Area Designation and Road Closure Order; Ada, Elmore, Canyon, and Owyhee...

    Science.gov (United States)

    1996-03-22

    ... Vehicle Management Area Designation and Road Closure Order; Ada, Elmore, Canyon, and Owyhee Counties, ID... except for those portions of the NCA currently included within the Owyhee Front Special Recreation... Bruneau, Kuna, and Owyhee Management Framework Plans, and the Jarbidge Resource Management Plan....

  14. 61 FR 11862 - Shooting Closures and Restrictions in Ada, Canyon, Elmore, and Owyhee Counties, ID

    Science.gov (United States)

    1996-03-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Shooting Closures and Restrictions in Ada, Canyon, Elmore, and Owyhee Counties, ID AGENCY: Bureau of Land... Bruneau, Kuna, and Owyhee Management Framework Plans. Violation of this order is punishable by a fine...

  15. OSHA and ADA: "Reasonable Accommodation" in Training Persons with Developmental Disabilities.

    Science.gov (United States)

    Sandoz, Charles J.

    This paper documents an approach to meeting the training requirements of the Occupational Safety and Health Act (OSHA) and the "reasonable accommodation" requirements of the Americans with Disabilities Act (ADA) for individuals with developmental disabilities. It describes a training program used with three adult workers with mild mental…

  16. Anemia nos pacientes com insuficiência cardíaca avançada

    Directory of Open Access Journals (Sweden)

    Juliano Cardoso

    2010-10-01

    Full Text Available FUNDAMENTO: Anemia está associada à pior evolução nos pacientes com insuficiência cardíaca (IC. Entretanto, há poucos estudos sobre a anemia nos pacientes com IC avançada. OBJETIVO: Avaliar as características da anemia na IC em fase avançada. MÉTODOS: Foram incluídos 99 pacientes hospitalizados para compensação de IC (CF IV/NYHA, com idade > 18 anos e FEVE 12 g/dl. A anemia foi marcador independente de mau prognóstico na análise multivariada (mortalidade 47% vs 24,6%, p = 0,016, risco relativo 2,54. CONCLUSÃO: Anemia acomete, aproximadamente, 1/3 dos pacientes com IC avançada, e a deficiência de ferro é uma importante etiologia. Pacientes anêmicos são mais idosos e apresentaram função renal mais deteriorada. A melhora da congestão não foi suficiente para melhorar a anemia na maioria dos casos. Nos pacientes com IC avançada, a anemia é marcador independente de mau prognóstico.

  17. How We Manage Adenosine Deaminase-Deficient Severe Combined Immune Deficiency (ADA SCID).

    Science.gov (United States)

    Kohn, Donald B; Gaspar, H Bobby

    2017-02-14

    Adenosine deaminase-deficient severe combined immune deficiency (ADA SCID) accounts for 10-15% of cases of human SCID. From what was once a uniformly fatal disease, the prognosis for infants with ADA SCID has improved greatly based on the development of multiple therapeutic options, coupled with more frequent early diagnosis due to implementation of newborn screening for SCID. We review the various treatment approaches for ADA SCID including allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen-matched sibling or family member or from a matched unrelated donor or a haplo-identical donor, autologous HSCT with gene correction of the hematopoietic stem cells (gene therapy-GT), and enzyme replacement therapy (ERT) with polyethylene glycol-conjugated adenosine deaminase. Based on growing evidence of safety and efficacy from GT, we propose a treatment algorithm for patients with ADA SCID that recommends HSCT from a matched family donor, when available, as a first choice, followed by GT as the next option, with allogeneic HSCT from an unrelated or haplo-identical donor or long-term ERT as other options.

  18. Automatic Player Detection and Recognition in Images Using AdaBoost

    NARCIS (Netherlands)

    Mahmood, Zahid; Ali, Tauseef; Khattak, Shadid

    2012-01-01

    In this work we developed an augmented reality sports broadcasting application for enhanced end-user experience. The proposed system consists of three major steps. In the first step each player is detected using AdaBoost Algorithm. In second step, same algorithm is used to detect face in each player

  19. CREASE 6.0 Catalog of Resources for Education in Ada and Software Engineering

    Science.gov (United States)

    1992-02-01

    Addison-Wesley, 1989. Gonzaler , D.W. Ada Programming Handbook. Compiler(s): DEC Compiler Conpumr(s): Vax-under VMS ScIedu/e The class meets twice a...Successfully completed another high-order programming course Credit Hours: 3 Point of Contact: Sergio An toy, Dept. of Computer Science, Portland State

  20. Infrastructure Measures versus ADAS for Traffic Safety - Application of the Grey Relational Analysis Evaluation Method

    NARCIS (Netherlands)

    Lu, M.; Wevers, K.; Heijden, R.E.C.M. van der; Marchau, V.A.W.J.

    2005-01-01

    Two of the main approaches to improve traffic safety are extensive redesign of the physical road infrastructure and large-scale implementation of Advanced Driver Assistance Systems (ADAS). These strategies are to a large extent substitutes, but also partly complementary. This paper determines strate

  1. Construction of acetoin high-producing Bacillus subtilis strain

    Directory of Open Access Journals (Sweden)

    Yanjun Tian

    2016-07-01

    Full Text Available This paper describes the construction and selection of a high-producing mutant, Bacillus subtilis HB-32, with enhanced acetoin yield and productivity. The mutant was obtained by the protoplast fusion of a Bacillus subtilis mutant TH-49 (Val− producing acetoin and Bacillus licheniformis AD-30 producing α-acetolactate decarboxylase, with the fusogen polyethylene glycol and after the regeneration and selection, etc. of the fusant. The acetoin production reached 49.64 g/L, which is an increase of 61.8% compared to that of B. subtilis strain TH-49. Random amplified polymorphic DNA analysis was performed to determine the mutagenic and protoplast fusion effects and the genomic changes in the acetoin high-producing strain compared to the parent strains at the molecular level. The constructed strain was shown to be promising for large-scale acetoin production. Future studies should focus on the application of the mutant strain in practice.

  2. COMPARISION OF ADENOSINE DEAMINASE [ADA] LEVELS WITH CYTO-CHEMICAL ANALYSIS OF PLEURAL FLUIDS TO DIFFERENTIATE TUBERCULAR AND NON â TUBERCULAR EFFUSIONS

    Directory of Open Access Journals (Sweden)

    Choukimath M Sharanabasav

    2013-12-01

    Full Text Available This study is intended to utilize biochemical parameters like ADA and protein levels in comparison with cell count and cell type in pleural fluid to differentiate tubercular and non-tubercular effusions. We have analyzed a total of 208 cases and among them 59.61% cases were ADA positive and 40.39% cases were ADA negative, and 156 cases were exudates and 52 cases were transudates. Categorized these effusions into 4 groups taking consideration of ADA, cell count, lymphocyte and protein levels as exudate with ADA positive, exudate with ADA negative, transudate with ADA positive and transudate with ADA negative. This study has shown promising results to diagnose tuberculosis with immediate and cost effectiveness that can be undertaken by any basic laboratory, in a endemic areas and developing countries like India

  3. Production of astaxanthin from cellulosic biomass sugars by mutants of the yeast Phaffia rhodozyma

    Science.gov (United States)

    Astaxanthin is a carotenoid of high value to the aquaculture, nutraceutical, and pharmaceutical industries. Three mutant strains of the astaxanthin-producing yeast Phaffia rhodozyma, which were derived from the parent strain ATCC 24202 (UCD 67-210) and designated JTM166, JTM185, and SSM19, were test...

  4. Repressor mutant forms of the Azospirillum brasilense NtrC protein.

    Science.gov (United States)

    Huergo, Luciano F; Assumpção, Marcelo C; Souza, Emanuel M; Steffens, M Berenice R; Yates, M Geoffrey; Chubatsu, Leda S; Pedrosa, Fábio O

    2004-10-01

    The Azospirillum brasilense mutant strains FP8 and FP9, after treatment with nitrosoguanidine, showed a null Nif phenotype and were unable to use nitrate as their sole nitrogen source. Sequencing of the ntrC genes revealed single nucleotide mutations in the NtrC nucleotide-binding site. The phenotypes of these strains are discussed in relation to their genotypes.

  5. HBV genotypes prevalence, precore and basal core mutants in Morocco.

    Science.gov (United States)

    Baha, Warda; Ennaji, My Mustapha; Lazar, Fatiha; Melloul, Marouane; El Fahime, Elmostafa; El Malki, Abdelouahad; Bennani, Abdelouaheb

    2012-08-01

    The study of hepatitis B virus (HBV) genomic heterogeneity has become a major issue in investigations aimed at understanding the relationship between HBV mutants and the wide spectrum of clinical and pathological conditions associated with HBV infection. The objective of the current study was to find out the pattern of HBV genotypes circulating in Morocco and to investigate the precore (PC) and basal core promoter (BCP) mutants' status in Moroccan chronic hepatitis B patients. Viral genotypes were determined in 221 chronic carriers using INNO-LiPA HBV assay and hemi-nested PCR. Phylogenetic analysis was performed in 70 samples, and multiplex PCR method was used to confirm some genotyping results. PC and CP mutants were determined using Inno-Lipa. All isolates were successfully genotyped. The genotype distribution was D in 90.45% of cases, A (5.9%), E (1 case), and mixed genotypes (5 A/D and 2 D/F) in 3.17% patients. HBV carried in the HBV/D samples could be assigned to D7 (63.3%), D1 (32.7%) and 2% of strains to each D4 and D5, all HBV/A belonged to A2 subgenotype and HBV/E strain could not be sub-genotyped. In 70 studied strains, HBV mutants were detected in 88.6% of cases; PC mutants were detected in (40%) of patients and 21.5% present a mixture of wild type and G1896A mutation. BCP mutants were observed in 65.7% of cases, 22.9% were found to have the T1762/1764A double mutation, 18.6% had A1762/1764T mutation and 22.9% of patients showed the A1762T/G1764A double mutation with either A1762T/G1764T mutation. Co-infection by PC and BCP mutants was detected in 52.9% of cases. Movement from place to place most likely shapes the observed genotype distribution and consequent prevalence of genotypes other than A2 or D7 in this population. High circulation of PC and BCP mutants is common in chronic hepatitis B infection in Morocco.

  6. Strain improvement of Gluconacetobacter xylinus NCIM 2526 for ...

    African Journals Online (AJOL)

    TUOYO

    2010-08-09

    Aug 9, 2010 ... wild strain. The mutant GHUV4 gave cellulose yield of 3.92 g/l which was 30% more than the wild strain ... One of the. BC application problems in industry is its low productivity. One approach to combat BC productivity is strain.

  7. Characterization and E protein expression of mutant strains during persistent infection of KN73 cells with Japanese encephalitis virus%KN73细胞持续感染乙脑病毒的模型中变异株性状及E蛋白表达

    Institute of Scientific and Technical Information of China (English)

    冯国和; 竹上勉; 赵桂珍

    2002-01-01

    目的研究乙脑病毒变异的特性以及变异株性状与E蛋白表达的关系.方法通过应用乙脑病毒的野生株以及人肝癌细胞KN73建立持续感染模型.采用胰蛋白酶消化技术每周进行细胞传代.经反复冻融收集持续感染细胞内病毒.采用BHK细胞空斑实验方法进行病毒滴定.采用间接免疫荧光方法检测E和NS3蛋白抗原.采用Western印迹杂交检测E和NS3蛋白的表达.结果感染早期(24小时-36小时)野生株感染的KN73细胞的培养液中病毒滴度为106 PFU/ml.在感染后期(3年)滴度为103-4 PFU/ml.病毒重叠感染实验发现在急性重叠感染野生株的持续感染KN73细胞中培养液的病毒滴度比在同一时相急性感染的正常KN73细胞培养液的滴度要低得多.间接免疫荧光检测表明,在持续感染的KN73细胞中病毒抗原的存在低于急性感染的KN73细胞.Western印迹杂交检测表明,E、NS3蛋白的分子量分别为53KD和73KD.在持续感染的KN73细胞中NS3蛋白的表达很稳定,但E蛋白的表达却明显受抑.结论从持续感染的KN73细胞中获得的病毒具有缺陷干扰病毒的一些特性且参与持续感染,其毒力和增殖均低于亲本病毒.这些变异可能与E蛋白表达减少有关.%Objective To study the character of mutants originating from Japanese encephalitis viruses and the relationship between the characterization of mutant strains and E protein expression.Methods Persistent infection was established with standard strains of Japanese encephalitis viruse, known as parental viruse, in a human hepatoma cell line, KN73. Cells were subcultured weekly using trypsinization techniques. Cell-associated viruses of persistently infected cells were collected by a freeze and thaw method. Virus titers were examined by plaque method using baby hamster kidney (BHK) cells. Indirect immunofluorescence assays were used to examine E and NS3 protein antigens. Wester*# n blot analysis was used to test

  8. Mutant prevention concentrations of four carbapenems against gram-negative rods.

    Science.gov (United States)

    Credito, Kim; Kosowska-Shick, Klaudia; Appelbaum, Peter C

    2010-06-01

    We tested the propensities of four carbapenems to select for resistant Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii mutants by determining the mutant prevention concentrations (MPCs) for 100 clinical strains with various ss-lactam phenotypes. Among the members of the Enterobacteriaceae family and A. baumannii strains, the MPC/MIC ratios were mostly 2 to 4. In contrast, for P. aeruginosa the MPC/MIC ratios were 4 to > or =16. The MPC/MIC ratios for beta-lactamase-positive K. pneumoniae and E. coli isolates were much higher (range, 4 to >16 microg/ml) than those for ss-lactamase-negative strains.

  9. Mutant Prevention Concentrations of Four Carbapenems against Gram-Negative Rods▿ †

    Science.gov (United States)

    Credito, Kim; Kosowska-Shick, Klaudia; Appelbaum, Peter C.

    2010-01-01

    We tested the propensities of four carbapenems to select for resistant Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii mutants by determining the mutant prevention concentrations (MPCs) for 100 clinical strains with various ß-lactam phenotypes. Among the members of the Enterobacteriaceae family and A. baumannii strains, the MPC/MIC ratios were mostly 2 to 4. In contrast, for P. aeruginosa the MPC/MIC ratios were 4 to ≥16. The MPC/MIC ratios for β-lactamase-positive K. pneumoniae and E. coli isolates were much higher (range, 4 to >16 μg/ml) than those for ß-lactamase-negative strains. PMID:20308376

  10. Cariogenicity of a lactate dehydrogenase-deficient mutant of Streptococcus mutans serotype c in gnotobiotic rats.

    OpenAIRE

    FitzGerald, R.J.; Adams, B. O.; Sandham, H. J.; Abhyankar, S

    1989-01-01

    A lactate dehydrogenase-deficient (Ldh-) mutant of a human isolate of Streptococcus mutans serotype c was tested in a gnotobiotic rat caries model. Compared with the wild-type Ldh-positive (Ldh+) strains, it was significantly (alpha less than or equal to 0.005) less cariogenic in experiments with two different sublines of Sprague-Dawley rats. The Ldh- mutant strain 044 colonized the oral cavity of the test animals to the same extent as its parent strain 041, although its initial implantation ...

  11. Repair of ultraviolet-irradiated transforming DNA in A recA mutant of Haemophilus influenzae

    Energy Technology Data Exchange (ETDEWEB)

    Stuy, J.H.; Walter, R.B. (Florida State Univ., Tallahassee (USA). Dept. of Biological Science)

    1983-04-01

    Ultraviolet-irradiated transforming DNA was assayed on a wild-type strain of Haemophilus influenzae strain Rd, on an excision repair-deficient (uvr-2) mutant, on a recombination repair-deficient (recA4) mutant, and on a strain carrying both mutations. The donor DNA had a point mutation genetic marker (strAl) and a long nonhomologous plasmid-derived DNA segment inserted in the HPl prophage. The shape of the inactivation curves suggested that only recombination was responsible for the inverse square root kinetics observed with excision repair-proficient recipients.

  12. [Production of carotene and lycopene by mutants of Streptomyces globisporus 1912 cultivated on mealy media].

    Science.gov (United States)

    Holembiovs'ka, S L; Matseliukh, B P

    2008-01-01

    Carotenoids produced by strains 4Crt and 4Lcp, spontaneous mutants oflandomycin E producer Streptomyces globisporus 1912 with activated cryptic genes of carotenogenesis, were identified, and their quantitative output was studied after growth of Streptomycete cultures on different mealy media in shake flasks. On the basis of chromatographic mobility and maxima of absorption spectra of purified pigments they were related to lycopene, beta- and phi-carotene (isorenieratene). It was shown that strain 4Crt synthesizes both carotenoids, while its spontaneous mutant 4Lcp--only lycopene. The greatest output of lycopene (27.24 mg/l) was observed after cultivation of 4Lcp strain on soy-corn medium.

  13. Spt-Ada-Gcn5-Acetyltransferase (SAGA) Complex in Plants: Genome Wide Identification, Evolutionary Conservation and Functional Determination

    Science.gov (United States)

    Srivastava, Rakesh; Rai, Krishan Mohan; Pandey, Bindu; Singh, Sudhir P.; Sawant, Samir V.

    2015-01-01

    The recruitment of RNA polymerase II on a promoter is assisted by the assembly of basal transcriptional machinery in eukaryotes. The Spt-Ada-Gcn5-Acetyltransferase (SAGA) complex plays an important role in transcription regulation in eukaryotes. However, even in the advent of genome sequencing of various plants, SAGA complex has been poorly defined for their components and roles in plant development and physiological functions. Computational analysis of Arabidopsis thaliana and Oryza sativa genomes for SAGA complex resulted in the identification of 17 to 18 potential candidates for SAGA subunits. We have further classified the SAGA complex based on the conserved domains. Phylogenetic analysis revealed that the SAGA complex proteins are evolutionary conserved between plants, yeast and mammals. Functional annotation showed that they participate not only in chromatin remodeling and gene regulation, but also in different biological processes, which could be indirect and possibly mediated via the regulation of gene expression. The in silico expression analysis of the SAGA components in Arabidopsis and O. sativa clearly indicates that its components have a distinct expression profile at different developmental stages. The co-expression analysis of the SAGA components suggests that many of these subunits co-express at different developmental stages, during hormonal interaction and in response to stress conditions. Quantitative real-time PCR analysis of SAGA component genes further confirmed their expression in different plant tissues and stresses. The expression of representative salt, heat and light inducible genes were affected in mutant lines of SAGA subunits in Arabidopsis. Altogether, the present study reveals expedient evidences of involvement of the SAGA complex in plant gene regulation and stress responses. PMID:26263547

  14. Spt-Ada-Gcn5-Acetyltransferase (SAGA Complex in Plants: Genome Wide Identification, Evolutionary Conservation and Functional Determination.

    Directory of Open Access Journals (Sweden)

    Rakesh Srivastava

    Full Text Available The recruitment of RNA polymerase II on a promoter is assisted by the assembly of basal transcriptional machinery in eukaryotes. The Spt-Ada-Gcn5-Acetyltransferase (SAGA complex plays an important role in transcription regulation in eukaryotes. However, even in the advent of genome sequencing of various plants, SAGA complex has been poorly defined for their components and roles in plant development and physiological functions. Computational analysis of Arabidopsis thaliana and Oryza sativa genomes for SAGA complex resulted in the identification of 17 to 18 potential candidates for SAGA subunits. We have further classified the SAGA complex based on the conserved domains. Phylogenetic analysis revealed that the SAGA complex proteins are evolutionary conserved between plants, yeast and mammals. Functional annotation showed that they participate not only in chromatin remodeling and gene regulation, but also in different biological processes, which could be indirect and possibly mediated via the regulation of gene expression. The in silico expression analysis of the SAGA components in Arabidopsis and O. sativa clearly indicates that its components have a distinct expression profile at different developmental stages. The co-expression analysis of the SAGA components suggests that many of these subunits co-express at different developmental stages, during hormonal interaction and in response to stress conditions. Quantitative real-time PCR analysis of SAGA component genes further confirmed their expression in different plant tissues and stresses. The expression of representative salt, heat and light inducible genes were affected in mutant lines of SAGA subunits in Arabidopsis. Altogether, the present study reveals expedient evidences of involvement of the SAGA complex in plant gene regulation and stress responses.

  15. Ultra-violet-resistant mutants of Bacillus thuringiensis

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.R.; Karunakaran, V. (Polytechnic of Central London (UK). Faculty of Engineering and Science, School of Biological and Health Sciences); Burges, H.D. (Institute of Horticultural Research, Littlehampton (UK)); Hacking, A.J. (Reading Univ. (UK). Dextra Labs.Ltd.)

    1991-06-01

    One of the main disadvantages of using Bacillus thuringiensis as an insecticide is that the spore and crystal preparations applied to foliage are readily washed away by rain and are inactivated by sunlight. Spores from some strains of B. thuringiensis have been shown to be highly sensitive to u.v. light. This study has demonstrated how mutants with increased resistance to u.v., isolated by successive rounds of u.v. irradiation, and additionally with increased specific pathogenicity can be isolated. These techniques should be applied to strains that are frequently used in the industrial production of B.thuringiensis toxin. (author).

  16. Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; ZHANG Jian; YANG Fan; WANG Kai; SHEN Si-Le; LIU Bing-Bing; ZOU Bo; ZOU Guang-Tian

    2011-01-01

    The mutant strains of aspergillus oryzae (HP300a) are screened under 300 Mpa for 20min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively.

  17. Azotobacter vinelandii mutS: nucleotide sequence and mutant analysis.

    OpenAIRE

    Le, O; Shen, B.; Iismaa, S E; Burgess, B K

    1993-01-01

    An Azotobacter vinelandii homolog to the Salmonella typhimurium mutS gene was discovered upstream of the fdxA gene. The product of this gene is much more similar to S. typhimurium MutS than either is to the HexA protein of Streptococcus pneumoniae. An A. vinelandii delta mutS mutant strain was shown to have a spontaneous mutation frequency 65-fold greater than that of the wild type.

  18. Reverse genetics in Chlamydomonas: a platform for isolating insertional mutants

    OpenAIRE

    de Montaigu Amaury; Magneschi Leonardo; Catalanotti Claudia; Yang Wenqiang; Mus Florence; Pootakham Wirulda; Gonzalez-Ballester David; Higuera Jose J; Prior Matthew; Galván Aurora; Fernandez Emilio; Grossman Arthur R

    2011-01-01

    Abstract A method was developed to identify insertional mutants of Chlamydomonas reinhardtii disrupted for selected target genes. The approach relies on the generation of thousands of transformants followed by PCR-based screenings that allow for identification of strains harboring the introduced marker gene within specific genes of interest. Our results highlight the strengths and limitations of two independent screens that differed in the nature of the marker DNA used (PCR-amplified fragment...

  19. Enhancement of yellow pigment production by intraspecific protoplast fusion of Monascus spp. yellow mutant (ade(-)) and white mutant (prototroph).

    Science.gov (United States)

    Klinsupa, Worawan; Phansiri, Salak; Thongpradis, Panida; Yongsmith, Busaba; Pothiratana, Chetsada

    2016-01-10

    To breed industrially useful strains of a slow-growing, yellow pigment producing strain of Monascus sp., protoplasts of Monascus purpureus yellow mutant (ade(-)) and rapid-growing M. purpureus white mutant (prototroph) were fused and fusants were selected on minimal medium (MM). Preliminary conventional protoplast fusion of the two strains was performed and the result showed that only white colonies were detected on MM. It was not able to differentiate the fusants from the white parental prototroph. To solve this problem, the white parental prototroph was thus pretreated with 20mM iodoacetamide (IOA) for cytoplasm inactivation and subsequently taken into protoplast fusion with slow-growing Monascus yellow mutant. Under this development technique, only the fusants, with viable cytoplasm from Monascus yellow mutant (ade(-)), could thus grow on MM, whereas neither IOA pretreated white parental prototroph nor yellow auxotroph (ade(-)) could survive. Fifty-three fusants isolated from yellow colonies obtained through this developed technique were subsequently inoculated on complete medium (MY agar). Fifteen distinguished yellow colonies from their parental yellow mutant were then selected for biochemical, morphological and fermentative properties in cassava starch and soybean flour (SS) broth. Finally, three most stable fusants (F7, F10 and F43) were then selected and compared in rice solid culture. Enhancement of yellow pigment production over the parental yellow auxotroph was found in F7 and F10, while enhanced glucoamylase activity was found in F43. The formation of fusants was further confirmed by monacolin K content, which was intermediate between the two parents (monacolin K-producing yellow auxotroph and non-monacolin K producing white prototroph).

  20. Construction and immunogenicity of a ∆apxIC/ompP2 mutant of Actinobacillus pleuropneumoniae and Haemophilus parasuis

    Directory of Open Access Journals (Sweden)

    Qiong Liu

    2013-03-01

    Full Text Available The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1, encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1 was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 × 107 CFU and 3.5 × 105 CFU respectively. The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.

  1. Construction and immunogenicity of a ∆apxIC/ompP2 mutant of Actinobacillus pleuropneumoniae and Haemophilus parasuis.

    Science.gov (United States)

    Liu, Qiong; Gong, Yuheng; Cao, Yuqin; Wen, Xintian; Huang, Xiaobo; Yan, Qigui; Huang, Yong; Cao, Sanjie

    2013-03-06

    The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1), encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1) was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 × 10(7) CFU and 3.5 × 10(5) CFU respectively). The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.

  2. EMMA—mouse mutant resources for the international scientific community

    Science.gov (United States)

    Wilkinson, Phil; Sengerova, Jitka; Matteoni, Raffaele; Chen, Chao-Kung; Soulat, Gaetan; Ureta-Vidal, Abel; Fessele, Sabine; Hagn, Michael; Massimi, Marzia; Pickford, Karen; Butler, Richard H.; Marschall, Susan; Mallon, Ann-Marie; Pickard, Amanda; Raspa, Marcello; Scavizzi, Ferdinando; Fray, Martin; Larrigaldie, Vanessa; Leyritz, Johan; Birney, Ewan; Tocchini-Valentini, Glauco P.; Brown, Steve; Herault, Yann; Montoliu, Lluis; de Angelis, Martin Hrabé; Smedley, Damian

    2010-01-01

    The laboratory mouse is the premier animal model for studying human disease and thousands of mutants have been identified or produced, most recently through gene-specific mutagenesis approaches. High throughput strategies by the International Knockout Mouse Consortium (IKMC) are producing mutants for all protein coding genes. Generating a knock-out line involves huge monetary and time costs so capture of both the data describing each mutant alongside archiving of the line for distribution to future researchers is critical. The European Mouse Mutant Archive (EMMA) is a leading international network infrastructure for archiving and worldwide provision of mouse mutant strains. It operates in collaboration with the other members of the Federation of International Mouse Resources (FIMRe), EMMA being the European component. Additionally EMMA is one of four repositories involved in the IKMC, and therefore the current figure of 1700 archived lines will rise markedly. The EMMA database gathers and curates extensive data on each line and presents it through a user-friendly website. A BioMart interface allows advanced searching including integrated querying with other resources e.g. Ensembl. Other resources are able to display EMMA data by accessing our Distributed Annotation System server. EMMA database access is publicly available at http://www.emmanet.org. PMID:19783817

  3. Hepatitis B escape mutants in Scottish blood donors.

    Science.gov (United States)

    Larralde, Osmany; Dow, Brian; Jarvis, Lisa; Davidson, Fiona; Petrik, Juraj

    2013-06-01

    Hepatitis B virus (HBV) remains as the viral infection with the highest risk of transmission by transfusion. This risk is associated with window period donations, occult HBV infection (OBI) and the emergence of escape mutants, which render blood donations false negative for hepatitis B surface antigen (HBsAg) serological testing. A retrospective study was conducted to gain insights into the molecular epidemiology of HBV escape mutants in Scottish blood donors. The criterion for selection was HBV positivity either by serology or nucleic acid testing (NAT). HBsAg detection was compared across several commercial immunoassays. The full length S gene from plasma samples was PCR amplified, cloned and expressed in HepG2 cells. Eight samples showed HBsAg discordant results, while 5 OBI samples were found. Four escape mutants, containing missense mutations in the S gene, are described here. These mutations impaired HBsAg detection both from HBV infected plasma samples and from recombinant proteins derived from its infected donors. Phylogenetic analysis showed that most of the mutants were clustered in the genotype D and were closely related to strains from Asia and the Middle East. We report here a proline substitution, outside the major hydrophilic region, that impaired HBsAg detection in vivo and in vitro, warning about the risk for the emergence of vaccine escape mutants with mutations outside the major neutralisation site.

  4. Identification of a mutant PfCRT-mediated chloroquine tolerance phenotype in Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Stephanie G Valderramos

    2010-05-01

    Full Text Available Mutant forms of the Plasmodium falciparum transporter PfCRT constitute the key determinant of parasite resistance to chloroquine (CQ, the former first-line antimalarial, and are ubiquitous to infections that fail CQ treatment. However, treatment can often be successful in individuals harboring mutant pfcrt alleles, raising questions about the role of host immunity or pharmacokinetics vs. the parasite genetic background in contributing to treatment outcomes. To examine whether the parasite genetic background dictates the degree of mutant pfcrt-mediated CQ resistance, we replaced the wild type pfcrt allele in three CQ-sensitive strains with mutant pfcrt of the 7G8 allelic type prevalent in South America, the Oceanic region and India. Recombinant clones exhibited strain-dependent CQ responses that ranged from high-level resistance to an incremental shift that did not meet CQ resistance criteria. Nonetheless, even in the most susceptible clones, 7G8 mutant pfcrt enabled parasites to tolerate CQ pressure and recrudesce in vitro after treatment with high concentrations of CQ. 7G8 mutant pfcrt was found to significantly impact parasite responses to other antimalarials used in artemisinin-based combination therapies, in a strain-dependent manner. We also report clinical isolates from French Guiana that harbor mutant pfcrt, identical or related to the 7G8 haplotype, and manifest a CQ tolerance phenotype. One isolate, H209, harbored a novel PfCRT C350R mutation and demonstrated reduced quinine and artemisinin susceptibility. Our data: 1 suggest that high-level CQR is a complex biological process dependent on the presence of mutant pfcrt; 2 implicate a role for variant pfcrt alleles in modulating parasite susceptibility to other clinically important antimalarials; and 3 uncover the existence of a phenotype of CQ tolerance in some strains harboring mutant pfcrt.

  5. Screening of Toxin Mutant of Dickeya zeae and Its Biological Characters

    Institute of Scientific and Technical Information of China (English)

    Jingyi ZHANG; Yutao WANG; Yanchang LI; Qiongguang LIU

    2013-01-01

    [Objective] This study aimed to screen toxin mutant of Dickeya zeae (Er-winia chrysanthemi pv. zeae) and investigate its biological characters. [Method] We obtained a toxin mutant strain D. zeae Ech7-3-42 by using acridine orange as a mutagenic agent and compared their biological characteristics and virulence between the toxin mutant and wild strain. [Result] There was no significant difference in pectin lyase, protease, cellulase and the production of extracellular polysaccharide and lipopolysaccharide, but significant difference in toxin biological activities and vir-ulence. Ech7-3-42 mutant did not produce toxin, as wel as the loss of virulence on rice and HR on tobacco, but did not lose the ability to soft rot on potato. Mutant strain Ech7-3-42 can infect rice root and then enriched in the root neck and stalk, but it could not cause rice foot rot. Dickeya zeae (wild and mutant strain) could be detected by PCR in the root neck and below the 1-2 cm long stem area, but could not be detected in the leaves. [Conclusion] We believed that toxin may be one of the important factors for D. zeae virulence on rice.

  6. Homozygosity for a novel adenosine deaminase (ADA) nonsense mutation (Q3>X) in a child with severe combined immunodeficiency (SCID)

    Energy Technology Data Exchange (ETDEWEB)

    Santisteban, I.; Arrendondo-Vega, F.X.; Kelly, S. [Duke Univ. Medical Center, Durham, NC (United States)]|[Hospital for Sick Children, Ontario (Canada)] [and others

    1994-09-01

    A Somali girl was diagnosed with ADA-deficient SCID at 7 mo; she responded well to PEG-ADA replacement and is now 3.3 yr old. ADA mRNA was undetectable (Northern) in her cultured T cells, but was present in T cells of her parents and two sibs. All PCR-amplified exon 1 genomic clones from the patient had a C>T transition at bp 7 relative to the start of translation, replacing Gln at codon 3 (AGA) with a termination codon (TGA, Q3>X). Patient cDNA (prepared by RT-PCR with a 5{prime} primer that covered codons 1-7) had a previously described polymorphism, K80>R, but was otherwise normal, indicating that no other coding mutations were present. A predicted new genomic BfaI restriction site was used to establish her homozygosity for Q3>X and to analyze genotypes of family members. We also analyzed the segregation of a variable Alu polyA-associated TAAA repeat (AluVpA) situated 5{prime} of the ADA gene. Three different AluVpA alleles were found, one of which was only present in the father and was not associated with his Q3>X allele. Because the father`s RBCs had only {approximately}15% of normal ADA activity, we analyzed his ADA cDNA. We found a G>A transition at bp 425 that substitutes Gln for Arg142, a solvent-accessible residue, and eliminates a BsmAI site in exon 5. ADA activity of the R142>Q in vitro translation product was 20-25% of wild type ADA translation product, suggesting that R142>Q is a new {open_quote}partial{close_quote} ADA deficiency mutation. As expected, Q3>X mRNA did not yield a detectable in vitro translation product. We conclude that the patient`s father is a compound heterozygote carrying the ADA Q3>X/R142>Q genotype. {open_quote}Partial{close_quote} ADA deficiency unassociated with immunodeficiency is relatively common in individuals of African descent. The present findings and previous observations suggest that {open_quote}partial{close_quote} ADA deficiency may have had an evolutionary advantage.

  7. Survival, growth, and localization of epiphytic fitness mutants of pseudomonas syringae on leaves

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, G.A.; Lindow, S.E. (Univ. of California, Berkeley, CA (United States))

    1994-10-01

    Among 82 epiphytic fitness mutants of a Pseudomonas syringae pv. syringae strain that were characterized in a previous study, 4 mutants were particularly intolerant of the stresses associated with dry leaf surfaces. These four mutants each exhibited distinctive behaviors when inoculated into and into plant leaves. For example, while non showed measurable growth on dry potato leaf surfaces, they grew to different population sizes in the intercellular space of bean leaves and on dry bean leaf surfaces, and one mutant appeared incapable of growth in both environments although it grew well on moist bean leaves. The presence of the parental strain did not influence the survival of the mutants immediately following exposure of leaves to dry, high-light incubation conditions, suggesting that the reduced survival of the mutants did not result from an inability to produce extracellular factors in planta. On moist bean leaves that were colonized by either a mutant or the wild type, the proportion of the total epiphytic population that was located in sizes protected from a surface sterilant was smaller for the mutants than for the wild type, indicating that the mutants were reduced in their ability to locate, multiply in, and/or survive in such protected sites. This reduced ability was only one of possible several factors contributing to the reduced epiphytic fitness of each mutant. Their reduced fitness was not specific to the host plant bean, since they also exhibited reduced fitness on the nonhost plant potato; the functions altered in these strains are thus of interest for their contribution to the general fitness of bacterial epiphytes. 52 refs., 6 figs., 1 tab.

  8. Isolation and characterization of Streptococcus mutans mutants defective in adherence and aggregation.

    Science.gov (United States)

    Murchison, H; Larrimore, S; Curtiss, R

    1981-12-01

    A method was developed which enriched for mutants of Streptococcus mutans that exhibit defects in adherence to glass, aggregation, or both. Mutants were isolated from derivatives of strains PS14 (serotype c) and 6715 (serotype g) after mutagenesis with either ethyl methane sulfonate or nitrous acid. Cell survival after mutagenesis was kept above 1 to 2% to enhance the probability that mutants resulted from single mutational events. A total of 117 mutants were isolated; they also displayed non-wild-type colony morphology on mitis salivarius agar. These mutants were examined for (i) adherence and aggregation after overnight growth in sucrose-containing medium, (ii) aggregation of nongrowing cells in the presence of 200 microgram of sucrose per ml or 20 microgram of dextran per ml, and (iii) dextranase production on blue dextran agar plates. Although we isolated mutants which exhibited a variation from the parent strain in only one of the traits tested, the majority of mutants exhibited defects in two or more characteristics. Thirty-eight stable mutants of independent origin were categorized into 13 separate phenotypic groups.

  9. Selection of Pseudomonas sp. strain HBP1 Prp for metabolism of 2-propylphenol and elucidation of the degradative pathway

    NARCIS (Netherlands)

    Kohler, Hans-Peter E.; Maarel, Marc J.E.C. van der; Kohler-Staub, Doris

    1993-01-01

    A mutant of Pseudomonas sp. strain HBP1, originally isolated on 2-hydroxybiphenyl, was selected for the ability to grow on 2-propylphenol as the sole carbon and energy source. In the mutant strain, which was designated as Pseudomonas sp. strain HBP1 Prp, the cellular induction mechanism involved in

  10. Isolation and characterization of radioresistant mutants in Bacillus subtilis and Bacillus thuringiensis

    Energy Technology Data Exchange (ETDEWEB)

    Kalinin, V.L.; Petrov, V.N.; Petrova, T.M. (AN SSSR, Leningrad. Inst. Yadernoj Fiziki)

    Vegetative cells of Bac. thuringiensis var. galleriae (the wild-type strain 351) are much more sensitive to lethal effects of UV light and /sup 60/Co-..gamma..-rays than those of Bac. subtilis (the wild-type strain 168). This difference is less pronounced for spores of these strains. By means of repeated ..gamma..-irradiation-regrowth cycles radioresistant mutants of Bac. thuringiensis Gamsup(r) 14 and Bac. subtilis Gamsup(r) 9 were selected. The vegetative cells of these mutants are correspondingly 19 times and 3.9 times more resistant to lethal effects of ..gamma..-radiation than the cells of the parental strains. The resistance of the Gamsup(r) mutant cells to lethal effects of UV light and H/sub 2/O/sub 2/ is also increased. The spores of the Gamsup(r) 14 mutant are 1.5-1.7 times more resistant to ..gamma..-radiation and UV light than the wild-type spores. The radioresistant mutants and the parental strains do not vary in their capacity for host-cell reactivation of UV- or ..gamma..-irradiated phages Tg13 and 105.

  11. Ilíada Latina: tradução e estudo literário da adaptação da Ilíada de Homero na antiguidade latina

    OpenAIRE

    2012-01-01

    O poema Ilíada Latina é um adaptação resumida em latim da Ilíada, da época de Nero. Já no século I a.C., o mito troiano passou a ser cada vez menos conhecido através da Ilíada, já que o grego era apenas aprendido pela elite romana. Durante a Idade Média, o grego deixou de ser aprendido no Ocidente, e assim, a Ilíada se perdeu durante esse período, até que estudiosos italianos começaram a aprender grego com os viajantes bizantinos no século XIV. A história da guerra de Troia, portanto, passou ...

  12. Ilíada Latina: tradução e estudo literário da adaptação da Ilíada de Homero na antiguidade latina

    OpenAIRE

    Priscilla Adriane Ferreira Almeida

    2012-01-01

    O poema Ilíada Latina é um adaptação resumida em latim da Ilíada, da época de Nero. Já no século I a.C., o mito troiano passou a ser cada vez menos conhecido através da Ilíada, já que o grego era apenas aprendido pela elite romana. Durante a Idade Média, o grego deixou de ser aprendido no Ocidente, e assim, a Ilíada se perdeu durante esse período, até que estudiosos italianos começaram a aprender grego com os viajantes bizantinos no século XIV. A história da guerra de Troia, portanto, passou ...

  13. QSAR analysis for ADA upon interaction with a series of adenine derivatives as inhibitors.

    Science.gov (United States)

    Moosavi-Movahedi, A A; Safarian, S; Hakimelahi, G H; Ataei, G; Ajloo, D; Panjehpour, S; Riahi, S; Mousavi, M F; Mardanyan, S; Soltani, N; Khalafi-Nezhad, A; Sharghi, H; Moghadamnia, H; Saboury, A A

    2004-01-01

    The kinetic parameters of adenosine deaminase such as Km and Ki were determined in the absence and presence of adenine derivatives (R1-R24) in sodium phosphate buffer (50 mM; pH 7.5) solution at 27 degrees C. These kinetic parameters were used for QSAR analysis. As such, we found some theoretical descriptors to which the binding affinity of adenosine deaminase (ADA) towards several adenine nucleosides as inhibitors is correlated. QSAR analysis has revealed that binding affinity of the adenine nucleosides upon interaction with ADA depends on the molecular volume, dipole moment of the molecule, electric charge around the N1 atom, and the highest of positive charge for the related molecules.

  14. Discrimination of Breast Tumors in Ultrasonic Images by Classifier Ensemble Trained with AdaBoost

    Science.gov (United States)

    Takemura, Atsushi; Shimizu, Akinobu; Hamamoto, Kazuhiko

    In this paper, we propose a novel method for acurate automated discrimination of breast tumors (carcinoma, fibroadenoma, and cyst). We defined 199 features related to diagnositic observations noticed when a doctor judges breast tumors, such as internal echo, shape, and boundary echo. These features included novel features based on a parameter of log-compressed K distribution, which reflect physical characteristics of ultrasonic B-mode imaging. Furthermore, we propose a discrimination method of breast tumors by using an ensemble classifier based on the multi-class AdaBoost algorithm with effective features selection. Verification by analyzing 200 carcinomas, 30 fibroadenomas and 30 cycts showed the usefulness of the newly defined features and the effectiveness of the discrimination by using an ensemble classifier trained by AdaBoost.

  15. Judge: don't wait for ADA review to file rehab act claim.

    Science.gov (United States)

    1997-06-13

    [Name removed] sued the [name removed] of Alcoholism and Substance Abuse ([name removed]) after he was denied reasonable accommodation for his HIV condition and then was terminated. [Name removed] said [name removed] and three top officials violated the two disability rights statutes as well as his constitutional right to equal protection under the 14th Amendment. According to the suit, [name removed] asked to see [name removed]'s policies on reasonable accommodation but was told there were none. Two months later he sought them again, asking permission to work at home and requesting HIV education for staff and management. Soon after these requests, [name removed] received a negative performance evaluation and was fired. [Name removed] filed Americans with Disabilities Act (ADA) discrimination charges with the Equal Employment Opportunity Commission (EEOC). [Name removed] lost his claims under the Rehabilitation Act because he waited for completion of an administrative review of his allegations under the ADA.

  16. Translating an AI application from Lisp to Ada: A case study

    Science.gov (United States)

    Davis, Gloria J.

    1991-01-01

    A set of benchmarks was developed to test the performance of a newly designed computer executing both Lisp and Ada. Among these was AutoClassII -- a large Artificial Intelligence (AI) application written in Common Lisp. The extraction of a representative subset of this complex application was aided by a Lisp Code Analyzer (LCA). The LCA enabled rapid analysis of the code, putting it in a concise and functionally readable form. An equivalent benchmark was created in Ada through manual translation of the Lisp version. A comparison of the execution results of both programs across a variety of compiler-machine combinations indicate that line-by-line translation coupled with analysis of the initial code can produce relatively efficient and reusable target code.

  17. Languages for artificial intelligence: Implementing a scheduler in LISP and in Ada

    Science.gov (United States)

    Hays, Dan

    1988-01-01

    A prototype scheduler for space experiments originally programmed in a dialect of LISP using some of the more traditional techniques of that language, was recast using an object-oriented LISP, Common LISP with Flavors on the Symbolics. This object-structured version was in turn partially implemented in Ada. The Flavors version showed a decided improvement in both speed of execution and readability of code. The recasting into Ada involved various practical problems of implementation as well as certain challenges of reconceptualization in going from one language to the other. Advantages were realized, however, in greater clarity of the code, especially where more standard flow of control was used. This exercise raised issues about the influence of programming language on the design of flexible and sensitive programs such as schedule planners, and called attention to the importance of factors external to the languages themselves such as system embeddedness, hardware context, and programmer practice.

  18. Extract from a mutant Rhodobacter sphaeroides as an enriched carotenoid source

    Directory of Open Access Journals (Sweden)

    Chih-Chiang Wang

    2016-03-01

    Full Text Available Background: The extract Lycogen™ from the phototrophic bacterium Rhodobacter sphaeroides (WL-APD911 has attracted significant attention because of its promising potential as a bioactive mixture, attributed in part to its anti-inflammatory properties and anti-oxidative activity. Objective: This study aims to investigate the components of Lycogen™ and its anti-inflammatory properties and anti-oxidative activity. Design and results: The mutant strain R. sphaeroides (WL-APD911 whose carotenoid 1,2-hydratase gene has been altered by chemical mutagenesis was used for the production of a new carotenoid. The strain was grown at 30°C on Luria–Bertani (LB agar plates. After a 4-day culture period, the mutant strain displayed a 3.5-fold increase in carotenoid content, relative to the wild type. In the DPPH test, Lycogen™ showed more potent anti-oxidative activity than lycopene from the wild-type strain. Primary skin irritation test with hamsters showed no irritation response in hamster skins after 30 days of treatment with 0.2% Lycogen™. Chemical investigations of Lycogen™ using nuclear magnetic resonance (NMR 1H, 13C, and COSY/DQCOSY spectra have identified spheroidenone and methoxyneurosporene. Quantitative analysis of these identified compounds based on spectral intensities indicates that spheroidenone and methoxyneurosporene are major components (approximately 1:1; very small quantities of other derivatives are also present in the sample. Conclusions: In this study, we identified the major carotenoid compounds contained in Lycogen™, including spheroidenone and methoxyneurosporene by high-resolution NMR spectroscopy analysis. The carotenoid content of this mutant strain of R. sphaeroides was 3.5-fold higher than that in normal strain. Furthermore, Lycogen™ from the mutant strain is more potent than lycopene from the wild-type strain and does not cause irritation in hamster skins. These findings suggest that this mutant strain has the

  19. Wild Accessions and Mutant Resources

    DEFF Research Database (Denmark)

    Kawaguchi, Masayoshi; Sandal, Niels Nørgaard

    2014-01-01

    Lotus japonicus, Lotus burttii, and Lotus filicaulis are species of Lotus genus that are utilized for molecular genetic analysis such as the construction of a linkage map and QTL analysis. Among them, a number of mutants have been isolated from two wild accessions: L. japonicus Gifu B-129...

  20. BASIC CRITERIA OF IRANIAN COMMERCIAL TOOTHPASTES AND AN ADA APPROVED BRAND (CREST)

    OpenAIRE

    2003-01-01

    Introduction: The effectiveness of fluorided toothpastes in reducing dental caries is well-documented, However not all fluorided toothpastes are equally effective. The objective of this study was to compare some essential criteria of six different toothpastes manufactured in Iran with one brand of ADA approved toothpaste (Crest). Methods. Six commercial toothpastes produced in Iran named as Paveh, Puneh, Nasim, Darugar, golpasand and saviz were compared with Crest in three subjects as fo...

  1. Execução forçada das obrigações

    Directory of Open Access Journals (Sweden)

    João Máximo Rodrigues Neto

    2017-05-01

    Full Text Available O presente trabalho tem como escopo o estudo da execução forçada das obrigações e a evolução da tutela executiva ao longo dos anos, bem como aborda alguns pontos relacionados à teoria do inadimplemento. Tudo isso em uma ótica de prestígio da efetividade da prestação jurisdicional.

  2. Issues to be Considered in the Evaluation of Technical Proposals from the Ada (Trademark) Language Perspective.

    Science.gov (United States)

    2014-09-26

    facilities (software test bed, dynamic simulation) are proposed to support the testing phases? 17. What proprietary data rights (if any) are...and beginners; for example, is prompting via menus provided for beginners and single keystroke capability provided for experienced users? 2-13 - input...Statement of Work: - constraint and numeric error checking - dynamic storage management - exception management 2-1 * 2.3 IMPLEMENTATION LANGUAGE If Ada has

  3. VIII Olimpíada Brasileira de Astronomia e Astronáutica

    Science.gov (United States)

    Garcia Canalle, João Batista; Villas da Rocha, Jaime Fernando; Wuensche de Souza, Carlos Alexandre; Pereira Ortiz, Roberto; Aguilera, Nuricel Villalonga; Padilha, Maria De Fátima Catta Preta; Pessoa Filho, José Bezerra; Soares Rodrigues, Ivette Maria

    2007-07-01

    Neste trabalho apresentamos as motivações pelas quais organizamos, em conjunto, pela primeira vez, a Olimpíada Brasileira de Astronomia incluindo a Astronáutica, em colaboração com a Agência Espacial Brasileira. Esta ampliação contribuiu para atrair ainda mais alunos, professores, escolas e patrocinadores para participarem desta Olimpíada. Em 2005 participaram da VIII Olimpíada Brasileira de Astronomia e Astronáutica (VIII OBA) 187.726 alunos distribuídos por 3.229 escolas, pertencentes a todos os estados brasileiros, incluindo o Distrito Federal. O crescimento em número de alunos participantes foi 52,4% maior do que em 2004. Em abril de 2005 organizamos, em Itapecerica da Serra, SP, um curso para os 50 alunos previamente selecionados e participantes da VII OBA e ao final selecionamos, dentre eles, uma equipe de 5 alunos, os quais representaram o Brasil na X Olimpíada Internacional de Astronomia, na China, em outubro de 2005. Ganhamos, pela primeira vez, uma medalha de ouro naquele evento. Em Agosto de 2005, organizamos a VIII Escola de Agosto para 50 alunos e respectivos professores, em Águas de Lindóia, SP, juntamente com a XXXI reunião anual da Sociedade Astronômica Brasileira (SAB). Em novembro de 2005 realizamos a I Jornada Espacial, em São José dos Campos, com 22 alunos e 22 professores selecionados dentre os participantes que melhores resultados obtiveram nas questões de Astronáutica da VIII OBA. Neste trabalho detalhamos os resultados da VIII OBA bem como as ações subseqüentes.

  4. Analysis of Training-Related Issues in the Transition to Ada in the DON

    Science.gov (United States)

    1991-09-01

    X. T Co-Advisor David I. Wi chairanDepartment of Adminit ences ii ABSTRACT The Department of Defense has been continually plagued with problems in...engineering principals coupled with the programming power Ada has to offer, can lead to increased programming productivity. Productivity can be...shortages of software professionals. In addition, with more professionals trained in solid software engineering principals , code reusability will

  5. Study on Several Characteristics of Agaricus blazei Murril Strain J3 Irradiated by 60Co

    Institute of Scientific and Technical Information of China (English)

    WENG Bo-qi; JIANG Zhi-he; HUANG Ting-jun; CHEN Jian; ZHENG Wei-wen

    2003-01-01

    A new mutant strain J3 from Agaricus blazei Murril was obtained by 60Co irradiation. The yields of successive generations were increased more than 70% to compare with their original strain. The component analysis on amino acids and fatty acid illuminated that the nutrient value of strain J3 fruiting body was better than the original strain. The apparent nodule structure was found in the hyphea of J3 strain through the observation by scanning electron microscope. RAPD analysis showed the great difference of PCR fingerprints between J3 and its original strain. It is a promising mutant strain for further commercial development in the future.

  6. Nitrogen Control in Pseudomonas aeruginosa : Mutants Affected in the Synthesis of Glutamine Synthetase, Urease, and NADP-Dependent Glutamate Dehydrogenase

    NARCIS (Netherlands)

    Janssen, Dick B.; Habets, Winand J.A.; Marugg, Joey T.; Drift, Chris van der

    1982-01-01

    Mutants were isolated from Pseudomonas aeruginosa that were impaired in the utilization of a number of nitrogen sources. In contrast to the wild-type strain, these mutants appeared to be unable to derepress the formation of glutamine synthetase and urease under nitrogen-limited growth conditions, wh

  7. Rhizobium leguminosarum exoB mutants are deficient in the synthesis of UDP-glucose 4'-epimerase

    NARCIS (Netherlands)

    CREMERS, HCJC; Batley, M; Redmond, J W; Eijdems, Elisabeth; BREEDVELD, MW; ZEVENHUIZEN, LPTM; Pees, Elisabeth; Wijffelman, C A; Lugtenberg, Ben J.J.

    1990-01-01

    Rhizobium leguminosarum bv. viciae Exo- mutant strains RBL5523,exo7::Tn5,RBL5523,exo8::Tn5 and RBL5523,exo52::Tn5 are affected in nodulation and in the syntheses of lipopolysaccharide, capsular polysaccharide, and exocellular polysaccharide. These mutants were complemented for nodulation and for the

  8. Reinforced AdaBoost learning for object detection with local pattern representations.

    Science.gov (United States)

    Lee, Younghyun; Han, David K; Ko, Hanseok

    2013-01-01

    A reinforced AdaBoost learning algorithm is proposed for object detection with local pattern representations. In implementing AdaBoost learning, the proposed algorithm employs an exponential criterion as a cost function and Newton's method for its optimization. In particular, we introduce an optimal selection of weak classifiers minimizing the cost function and derive the reinforced predictions based on a judicial confidence estimate to determine the classification results. The weak classifier of the proposed method produces real-valued predictions while that of the conventional AdaBoost method produces integer valued predictions of +1 or -1. Hence, in the conventional learning algorithms, the entire sample weights are updated by the same rate. On the contrary, the proposed learning algorithm allows the sample weights to be updated individually depending on the confidence level of each weak classifier prediction, thereby reducing the number of weak classifier iterations for convergence. Experimental classification performance on human face and license plate images confirm that the proposed method requires smaller number of weak classifiers than the conventional learning algorithm, resulting in higher learning and faster classification rates. An object detector implemented based on the proposed learning algorithm yields better performance in field tests in terms of higher detection rate with lower false positives than that of the conventional learning algorithm.

  9. Software engineering and Ada (Trademark) training: An implementation model for NASA

    Science.gov (United States)

    Legrand, Sue; Freedman, Glenn

    1988-01-01

    The choice of Ada for software engineering for projects such as the Space Station has resulted in government and industrial groups considering training programs that help workers become familiar with both a software culture and the intricacies of a new computer language. The questions of how much time it takes to learn software engineering with Ada, how much an organization should invest in such training, and how the training should be structured are considered. Software engineering is an emerging, dynamic discipline. It is defined by the author as the establishment and application of sound engineering environments, tools, methods, models, principles, and concepts combined with appropriate standards, guidelines, and practices to support computing which is correct, modifiable, reliable and safe, efficient, and understandable throughout the life cycle of the application. Neither the training programs needed, nor the content of such programs, have been well established. This study addresses the requirements for training for NASA personnel and recommends an implementation plan. A curriculum and a means of delivery are recommended. It is further suggested that a knowledgeable programmer may be able to learn Ada in 5 days, but that it takes 6 to 9 months to evolve into a software engineer who uses the language correctly and effectively. The curriculum and implementation plan can be adapted for each NASA Center according to the needs dictated by each project.

  10. Using Ada to implement the operations management system in a community of experts

    Science.gov (United States)

    Frank, M. S.

    1986-01-01

    An architecture is described for the Space Station Operations Management System (OMS), consisting of a distributed expert system framework implemented in Ada. The motivation for such a scheme is based on the desire to integrate the very diverse elements of the OMS while taking maximum advantage of knowledge based systems technology. Part of the foundation of an Ada based distributed expert system was accomplished in the form of a proof of concept prototype for the KNOMES project (Knowledge-based Maintenance Expert System). This prototype successfully used concurrently active experts to accomplish monitoring and diagnosis for the Remote Manipulator System. The basic concept of this software architecture is named ACTORS for Ada Cognitive Task ORganization Scheme. It is when one considers the overall problem of integrating all of the OMS elements into a cooperative system that the AI solution stands out. By utilizing a distributed knowledge based system as the framework for OMS, it is possible to integrate those components which need to share information in an intelligent manner.

  11. Biocontrol potential of salinity tolerant mutants of Trichoderma harzianum against Fusarium oxysporum Potencial de biocontrole de mutantes sal-tolerantes de Trichoderma harzianum contra Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Hassan Abdel-Latif A. Mohamed

    2006-06-01

    Full Text Available Exposing a wild-type culture of Trichoderma harzianum to gamma irradiation induced two stable salt-tolerant mutants (Th50M6 and Th50M11. Under saline conditions, both mutants greatly surpassed their wild type strain in growth rate, sporulation and biological proficiency against Fusarium oxysporum, the causal agent of tomato wilt disease. Tolerant T. harzianum mutants detained a capability to grow and convinced sporulation in growth media containing up to 69 mM NaCl. In comparison with their parent strain, characterization of both mutants confirmed that they have reinforced contents of proline and hydroxyproline, relatively higher sodium content compared to potassium, calcium or magnesium contents, higher level of total phenols. Electrophoretic analysis of total soluble proteins in the salt tolerance mutant Th50M6 showed different bands accumulated in response to 69 mM NaCl. Data also showed that mutants produce certain active metabolites, such as chitinases, cellulases, beta-galactosidases, as well as, some antibiotics i.e., trichodermin, gliotoxin and gliovirin. Trichoderma mutants significantly reduced wilt disease incidence and improved yield and mineral contents of tomato plants under both saline and non-saline soil conditions, as well as, under infested and natural conditions. T. harzianum mutants were also more efficient in dropping the F. oxysporum growth in rhizosphere compared to the wild type strain. Population density of both mutants in rhizosphere far exceeded that of T. harzianum wild type strain.A exposição de uma cepa selvagem de Trichoderma harzianum à irradiação gama induziu dois mutantes tolerantes a sal (Th50M6 e Th50M11. Em condições salinas, os dois mutantes foram muito superiores à cepa selvagem em relação à velocidade de multiplicação, esporulação e eficiência contra Fusarium oxysporum, o agente causador da doença wilt do tomate. Os mutantes tolerantes foram capazes de multiplicação e esporulação em

  12. Isolation and characterization of ultraviolet light-sensitive mutants of the blue-green alga Anacystis nidulans.

    Science.gov (United States)

    Asato, Y.

    1972-01-01

    Three independently isolated ultraviolet light sensitive (uvs) mutants of Anacystis nidulans were characterized. Strain uvs-1 showed the highest sensitivity to UV by its greatly reduced photoreactivation capacity following irradiation. Pretreatment with caffeine suppressed the dark-survival curve of strain uvs-1, thus indicating the presence of excision enzymes involved in dark repair. Under 'black' and 'white' illumination, strain uvs-1 shows photorecovery properties comparable with wild-type cultures. Results indicate that strains uvs-1, uvs-35, and uvs-88 are probably genetically distinct UV-sensitive mutants.

  13. Genetic mapping of ada and adc mutations affecting the adaptive response of Escherichia coli to alkylating agents.

    Science.gov (United States)

    Sedgwick, B

    1982-05-01

    The adaptive response to alkylating agents is an inducible repair system which protects Escherichia coli against the mutagenicity and toxicity of these agents. Four mutations, ada-3, ada-5, ada-6, and adc-1, which confer differing phenotypes as regards this response, were shown to be cotransducible with gyrA, and were located at 47 min on the E. coli genetic map. A mutation already shown on the map at 47 min as tag (B. J. Bachmann and K. B. Low, Microbiol. Rev. 44:1--56, 1980; Karran et al., J. Mol. Biol. 140:101--127, 1980) is now known to be an ada mutation (G. Evensen and E. Seeberg, personal communication).

  14. Construction and Verification of LuxS-negative Mutants of Streptococcus Mutans and the Effect of the Absence of LuxS Gene on the Acid Tolerance

    Institute of Scientific and Technical Information of China (English)

    YU Dan-ni; CHEN Jie; ZHANG Yao-chao; HAN Yu-zhi

    2009-01-01

    Objective: To knock out the entire Luxs gene of Streptococcus mutans(S.mutans) UA159 strain via homologous recombination and construct a Luxs-deleted mutant strain of S. Mutans. To study the difference between the acid resistance of S. Mutans Ingbritt C international standard strain and the acid resistance of LuxS mutant strain. Methods: Two DNA fragments locating in the upper and downstream of Luxs gene were amplified and a erythromycin resistance gene of PJT10 between them were engineered into PUC19 plasmid for constructing the recombination plasmid pUCluxKO. Electrotransformation of S.mutans cells with pUCluxKO-mutant resulted in isolation of erythromycin resistant S. Mutans transformants, which was identified by polymerase chain reaction, V.harveyi BB170 luminescence bioassay and sequencing analysis. Solutions of S. Mutans standard strain and LuxS mutant strain with same density were made and cultured at pH 3.5 to 7.0 BHI liquid for the same period.Terminal growth situation was compared.Firstly acidized in pH 5.5 BHI liquid,the two strains were cultured at pH 3.0 BHI liquid. The acid tolerance responses of the two strains were compared.Results:Restriction endonuclease analyses showed that pUCluxKO-mutant vector had been successfully recombined. The Luxs-deleted status of S.mutans mutants was confirmed by PCR with primers which were specific for the genes of Luxs and Erythromycin resistance. S.mutans mutant can not induce bioluminescence, indiating the mutant had been successfully recombined. After twenty generations of culture, the constructed Chinese S.mutans mutants were confirmed to be stable. Significant difference of aciduricity was observed between S.mutans standard strain and LuxS mutant strain.The acid resistance of standard strain was stronger than that of LuxS mutant strain.The two strains both displayed the capability of acid tolerance responses. Conclusion:The S.mutans gene allelic exchange plasmid is constructed correctively and a Luxs

  15. Temperature-sensitive mutants of fowl plague virus: isolation and genetic characterization. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Almond, J.W.; McGeoch, D.; Barry, R.D.

    1979-01-30

    Forty-nine temperature-sensitive mutants of fowl plague virus (FPV) strain Rostock and four ts mutants of FPV-strain Dobson were isolated by utilizing two methods of plaque screening, after either spontaneous or chemically induced mutagenesis. Twenty-nine of the FPV-Rostock mutants were further characterized by genetic recombination studies and were found to fall into six high frequency recombination groups. The genome segment carrying the ts mutation in each group was identified by analyzing the gene composition of ts/sup +/ recombinants generated from crosses between representatives of each group and ts mutants of FPV-Dobson. It was concluded that the six groups correspond to mutations in six different genome segments, namely, those coding for the P/sub 1/, P/sub 2/, P/sub 3/, HA, NP, and NS proteins.

  16. Isolation of mutants deficient in acetyl-CoA synthetase and a possible regulator of acetate induction in Aspergillus niger.

    Science.gov (United States)

    Sealy-Lewis, H M; Fairhurst, V

    1998-07-01

    Acetate-non-utilizing mutants in Aspergillus niger were selected by resistance to 1.2% propionate in the presence of 0.1% glucose. Mutants showing normal morphology fell into two complementation groups. One class of mutant lacked acetyl-CoA synthetase but had high levels of isocitrate lyase, while the second class showed reduced levels of both acetyl-CoA synthetase and isocitrate lyase compared to the wild-type strain. By analogy with mutants selected by resistance to 1.2% propionate in Aspergillus nidulans, the properties of the mutants in A. niger suggest that the mutations are either in the structural gene for acetyl-CoA synthetase (acuA) or in a possible regulatory gene of acetate induction (acuB). A third class of mutant in a different complementation group was obtained which had abnormal morphology (yellow mycelium and few conidia); the specific lesion in these mutants has not been determined.

  17. Proceedings of the Annual Conference on Ada (Trademark) Technology (2nd) Held at Hampton, Virginia on March 27, 28, 1984.

    Science.gov (United States)

    1984-03-01

    to PDL as defined by Uaine and Gordon is a mission requiremonts and system parameters." ’ pidgin ’ language in that it uses the vocabulary of one...greatest advantage to a design language wnich generating a standard pidgin language merginq Ada is a subset of a target language is that ’iinten- with...commentary and English, appropriate Ada keywords are combined with annotations defined. These serve to extend the English narrative in the classical pidgin

  18. A High Accuracy Pedestrian Detection System Combining a Cascade AdaBoost Detector and Random Vector Functional-Link Net

    OpenAIRE

    Zhihui Wang; Sook Yoon; Shan Juan Xie; Yu Lu; Dong Sun Park

    2014-01-01

    In pedestrian detection methods, their high accuracy detection rates are always obtained at the cost of a large amount of false pedestrians. In order to overcome this problem, the authors propose an accurate pedestrian detection system based on two machine learning methods: cascade AdaBoost detector and random vector functional-link net. During the offline training phase, the parameters of a cascade AdaBoost detector and random vector functional-link net are trained by standard dataset. These...

  19. Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064

    Directory of Open Access Journals (Sweden)

    Eliton da Silva Vasconcelos

    2013-12-01

    Full Text Available Clavulanic acid (CA is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064. The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.

  20. Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064.

    Science.gov (United States)

    da Silva Vasconcelos, Eliton; de Lima, Vanderlei Aparecido; Goto, Leandro Seiji; Cruz-Hernández, Isara Lourdes; Hokka, Carlos Osamu

    2013-12-01

    Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.

  1. Prevention of GABA reduction during dough fermentation using a baker's yeast dal81 mutant.

    Science.gov (United States)

    Ando, Akira; Nakamura, Toshihide

    2016-10-01

    γ-Aminobutyric acid (GABA) is consumed by yeasts during fermentation. To prevent GABA reduction in bread dough, a baker's yeast mutant AY77 deficient in GABA assimilation was characterized and utilized for wheat dough fermentation. An amber mutation in the DAL81 gene, which codes for a positive regulator of multiple nitrogen degradation pathways, was found in the AY77 strain. The qPCR analyses of genes involved in nitrogen utilization showed that transcriptional levels of the UGA1 and DUR3 genes encoding GABA transaminase and urea transporter, respectively, are severely decreased in the AY77 cells. The AY77 strain cultivated by fed-batch culture using cane molasses exhibited inferior gas production during dough fermentation compared to that of wild-type strain AY13. However, when fed with molasses containing 0.5% ammonium sulfate, the mutant strain exhibited gas production comparable to that of the AY13 strain. In contrast to the AY13 strain, which completely consumed GABA in dough within 5 h, the AY77 strain consumed no GABA under either culture condition. Dough fermentation with the dal81 mutant strain should be useful for suppression of GABA reduction in breads.

  2. Molecular characterization of Tn5-induced symbiotic (Fix-) mutants of Rhizobium meliloti.

    OpenAIRE

    Zimmerman, J L; Szeto, W W; Ausubel, F M

    1983-01-01

    To investigate the expression of specific symbiotic genes during the development of nitrogen-fixing root nodules, we conducted a systematic analysis of nodule-specific proteins and RNAs produced after the inoculation of alfalfa roots with a series of Rhizobium meliloti mutants generated by site-directed transposon Tn5 mutagenesis. The mutagenized region of the Rhizobium genome covered approximately 10 kilobases and included the region encoding the nitrogenase polypeptides. All mutant strains ...

  3. Herpes simplex virus type 1 ribonucleotide reductase null mutants induce lesions in guinea pigs.

    Science.gov (United States)

    Turk, S R; Kik, N A; Birch, G M; Chiego, D J; Shipman, C

    1989-12-01

    Two herpes simplex virus type 1 ribonucleotide reductase null mutants, hrR3 and ICP6 delta, produced cutaneous lesions in guinea pigs as severe as those of wild-type strains. The lesions induced by hrR3 resulted from in vivo replication of the mutant virus, suggesting that this virus-encoded enzyme is nonessential for virus replication in guinea pigs.

  4. Rapid Purification and Characterization of Mutant Origin Recognition Complexes in Saccharomyces cerevisiae

    OpenAIRE

    Hironori eKawakami; Eiji eOhashi; Toshiki eTsurimoto; Tsutomu eKatayama

    2016-01-01

    Purification of the origin recognition complex (ORC) from wild-type budding yeast cells more than two decades ago opened up doors to analyze the initiation of eukaryotic chromosomal DNA replication biochemically. Although revised methods to purify ORC from overproducing cells were reported later, purification of mutant proteins using these systems still depends on time-consuming processes including genetic manipulation to construct and amplify mutant baculoviruses or yeast strains as well as ...

  5. Imipenem- and meropenem-resistant mutants of Enterobacter cloacae and Proteus rettgeri lack porins.

    Science.gov (United States)

    Raimondi, A; Traverso, A; Nikaido, H

    1991-01-01

    Carbapenems such as imipenem and meropenem are not rapidly hydrolyzed by commonly occurring beta-lactamases. Nevertheless, it was possible, by mutagenesis and selection, to isolate mutant strains of Enterobacter cloacae and Proteus rettgeri that are highly resistant to meropenem and imipenem. Two alterations were noted in the E. cloacae mutants. First, the mutant strains appeared to be strongly derepressed in the production of beta-lactamases, which reached a very high level when the strains were grown in the presence of imipenem. Second, these mutants were deficient in the production of nonspecific porins, as judged by the pattern of outer membrane proteins as well as by reconstitution assays of permeability. As with most porin-deficient mutants, their cultures were unstable, and their cultivation in the absence of carbapenems rapidly led to an overgrowth of porin-producing revertants. Analysis of the data suggests that the synergism between the lowered outer membrane permeability and the slow but significant hydrolysis of carbapenems by the overproduced enzymes can explain the resistance phenotypes quantitatively, although the possibility of alteration of the target cannot be excluded at present. With P. rettgeri mutants, there was no indication of further derepression of beta-lactamase, but the enzyme hydrolyzed imipenem much more efficiently than the E. cloacae enzyme did. In addition, the major porin was absent in one mutant strain. These results suggest that a major factor for the carbapenem resistance of these enteric bacteria is the porin deficiency, and this conclusion forms a contrast to the situation in Pseudomonas aeruginosa, in which the most prevalent class of imipenem-resistant mutants appears to lack the specific channel protein D2 yet retains the major nonspecific porin F. Images PMID:1656855

  6. Isolation of a Defective Prion Mutant from Natural Scrapie

    Science.gov (United States)

    Migliore, Sergio; Cosseddu, Gian Mario; Pirisinu, Laura; Riccardi, Geraldina; Nonno, Romolo

    2016-01-01

    It is widely known that prion strains can mutate in response to modification of the replication environment and we have recently reported that prion mutations can occur in vitro during amplification of vole-adapted prions by Protein Misfolding Cyclic Amplification on bank vole substrate (bvPMCA). Here we exploited the high efficiency of prion replication by bvPMCA to study the in vitro propagation of natural scrapie isolates. Although in vitro vole-adapted PrPSc conformers were usually similar to the sheep counterpart, we repeatedly isolated a PrPSc mutant exclusively when starting from extremely diluted seeds of a single sheep isolate. The mutant and faithful PrPSc conformers showed to be efficiently autocatalytic in vitro and were characterized by different PrP protease resistant cores, spanning aa ∼155–231 and ∼80–231 respectively, and by different conformational stabilities. The two conformers could thus be seen as different bona fide PrPSc types, putatively accounting for prion populations with different biological properties. Indeed, once inoculated in bank vole the faithful conformer was competent for in vivo replication while the mutant was unable to infect voles, de facto behaving like a defective prion mutant. Overall, our findings confirm that prions can adapt and evolve in the new replication environments and that the starting population size can affect their evolutionary landscape, at least in vitro. Furthermore, we report the first example of “authentic” defective prion mutant, composed of brain-derived PrPC and originating from a natural scrapie isolate. Our results clearly indicate that the defective mutant lacks of some structural characteristics, that presumably involve the central region ∼90–155, critical for infectivity but not for in vitro replication. Finally, we propose a molecular mechanism able to account for the discordant in vitro and in vivo behavior, suggesting possible new paths for investigating the molecular bases of

  7. Rapid Mutation of Spirulina platensis by a New Mutagenesis System of Atmospheric and Room Temperature Plasmas (ARTP) and Generation of a Mutant Library with Diverse Phenotypes

    Science.gov (United States)

    Zhang, Chong; Tan, Yinyee; Jiang, Peixia; Ge, Nan; Heping Li; Xing, Xinhui

    2013-01-01

    In this paper, we aimed to improve the carbohydrate productivity of Spirulina platensis by generating mutants with increased carbohydrate content and growth rate. ARTP was used as a new mutagenesis tool to generate a mutant library of S. platensis with diverse phenotypes. Protocol for rapid mutation of S. platensis by 60 s treatment with helium driven ARTP and high throughput screening method of the mutants using the 96-well microplate and microplate reader was established. A mutant library of 62 mutants was then constructed and ideal mutants were selected out. The characteristics of the mutants after the mutagenesis inclined to be stable after around 9th subculture, where the total mutation frequency and positive mutation frequency in terms of specific growth rate reached 45% and 25%, respectively. The mutants in mutant library showed diverse phenotypes in terms of cell growth rate, carbohydrate content and flocculation intensity. The positive mutation frequency in terms of cellular carbohydrate content with the increase by more than 20% percent than the wild strain was 32.3%. Compared with the wild strain, the representative mutants 3-A10 and 3-B2 showed 40.3% and 78.0% increase in carbohydrate content, respectively, while the mutant 4-B3 showed 10.5% increase in specific growth rate. The carbohydrate contents of the representative mutants were stable during different subcultures, indicating high genetic stability. ARTP was demonstrated to be an effective and non-GMO mutagenesis tool to generate the mutant library for multicellular microalgae. PMID:24319517

  8. Rapid mutation of Spirulina platensis by a new mutagenesis system of atmospheric and room temperature plasmas (ARTP and generation of a mutant library with diverse phenotypes.

    Directory of Open Access Journals (Sweden)

    Mingyue Fang

    Full Text Available In this paper, we aimed to improve the carbohydrate productivity of Spirulina platensis by generating mutants with increased carbohydrate content and growth rate. ARTP was used as a new mutagenesis tool to generate a mutant library of S. platensis with diverse phenotypes. Protocol for rapid mutation of S. platensis by 60 s treatment with helium driven ARTP and high throughput screening method of the mutants using the 96-well microplate and microplate reader was established. A mutant library of 62 mutants was then constructed and ideal mutants were selected out. The characteristics of the mutants after the mutagenesis inclined to be stable after around 9(th subculture, where the total mutation frequency and positive mutation frequency in terms of specific growth rate reached 45% and 25%, respectively. The mutants in mutant library showed diverse phenotypes in terms of cell growth rate, carbohydrate content and flocculation intensity. The positive mutation frequency in terms of cellular carbohydrate content with the increase by more than 20% percent than the wild strain was 32.3%. Compared with the wild strain, the representative mutants 3-A10 and 3-B2 showed 40.3% and 78.0% increase in carbohydrate content, respectively, while the mutant 4-B3 showed 10.5% increase in specific growth rate. The carbohydrate contents of the representative mutants were stable during different subcultures, indicating high genetic stability. ARTP was demonstrated to be an effective and non-GMO mutagenesis tool to generate the mutant library for multicellular microalgae.

  9. Phenotypic characterization of glucose repression mutants of Saccharomyce cerevisiae usinge experiments with C-13-labelled glucose

    DEFF Research Database (Denmark)

    Vijayendran, Raghevendran; Gombert, A.K.; Christensen, B.

    2004-01-01

    glucose. Through GC-MS analysis of the C-13 incorporated into the amino acids of cellular proteins, it was possible to obtain quantitative information on the function of the central carbon metabolism in the different mutants. Traditionally, such labelling data have been used to quantify metabolic fluxes...... through the use of a suitable mathematical model, but here we show that the raw labelling data may also be used directly for phenotypic characterization of different mutant strains. Different glucose derepressed strains investigated employed are the disruption mutants reg1, hxk2, grr1, mig1 and mig1mig2...... and the reference strain CEN.PK113-7D. Principal components analysis of the summed fractional labelling data show that deleting the genes HXK2 and GRR1 results in similar phenotype at the fluxome level, with a partial alleviation of glucose repression on the respiratory metabolism. Furthermore, deletion...

  10. [Biofilm Formation by the Nonflagellated flhB1 Mutant of Azospirillum brasilense Sp245].

    Science.gov (United States)

    Shelud'ko, A V; Filip'echeva, Yu A; Shumiliva, E M; Khlebtsov, B N; Burov, A M; Petrova, L P; Katsy, E I

    2015-01-01

    Azospirillum brasilense Sp245 with mixed flagellation are able to form biofilms on various surfaces. A nonflagellated mutant of this strain with inactivated chromosomal copy of the flhB gene (flhB1) was shown to exhibit specific traits at the later stages of biofilm formation on a hydrophilic (glass) surface. Mature biofilms of the flhB1::Omegon-Km mutant Sp245.1063 were considerably thinner than those of the parent strain Sp245. The biofilms of the mutant were more susceptible to the forces of hydrodynamic shear. A. brasilense Sp245 cells in biofilms were not found to possess lateral flagella. Cells with polar flagella were, however, revealed by atomic force microscopy of mature native biofilms of strain Sp245. Preservation of a polar flagellum (probably nonmotile) on the cells of A. brasilense Sp245 may enhance the biofilm stability.

  11. Isolation and characterization of a Saccharomyces cerevisiae mutant with impaired glutamate synthase activity.

    Science.gov (United States)

    Folch, J L; Antaramián, A; Rodríguez, L; Bravo, A; Brunner, A; González, A

    1989-12-01

    A mutant of Saccharomyces cerevisiae that lacks glutamate synthase (GOGAT) activity has been isolated. This mutant was obtained after chemical mutagenesis of a NADP-glutamate dehydrogenase-less mutant strain. The gdh gus mutant is a glutamate auxotroph. The genetic analysis of the gus mutant showed that the GOGAT-less phenotype is due to the presence of two loosely linked mutations. Evidence is presented which suggests the possibility that S. cerevisiae has two GOGAT activities, designated GOGAT A and GOGAT B. These activities can be distinguished by their pH optima and by their regulation by glutamate. Furthermore, one of the mutations responsible for the GOGAT-less phenotype affected GOGAT A activity, while the other mutation affected GOGAT B activity.

  12. [Phenotype analysis and mutant gene location of ventral yellow mouse (VY(Slac))].

    Science.gov (United States)

    Shi, Mei-Lian; Xu, Ping; Yin, Xiao-Shu; Yang, Wei-Wei; Gu, Mei-Er; Yu, Li-Ping; Liu, Gui-Jie; Wu, Bao-Jin

    2012-06-01

    The ventri-yellow pigmentation mouse (temporarily named VY(Slac)) arose spontaneously in the C57BL/6J inbred mouse strain, found and bred by Shanghai SLAC Laboratory Animal Co., Ltd. VY(Slac) presented a special phenotype marked by yellow coat on the ventral surface of neck and trunk that was without melanin deposition but maintained a normal structure. The number of melanocytes in epidermis and melanin in hair follicle of the abdominal skin of the mutant mouse were less than that of their background strain, while there was no significant difference between the dorsal skins of the two strains. This mutant phenotype was inherited as single-gene dominant inheritance, confirmed by genetic experiment, and there was no significant difference between VY(Slac) and B(6) for other biological parameters such as weight, anatomic and histological structures of major organs and blood physiology. When the linkage relationship between the genomic DNA samples of F(2) 48 mice (VY(Slac)D(2)F(1)×D(2)) and mutant phenotype were evaluated, the mutant gene was confirmed on chromosome 2 near D2Mit229. New microsatellite and SNP markers were selected to amplify genomic DNA samples of 196 F(2) mice and the mutant gene was narrowed down to 5.3 Mb region between rs13476833 and rs27310903 on chromosome 2. The preliminary results of our phenotype analysis and gene location provides a solid basis for further identification of this mutant gene.

  13. Comparison of the behavior of epiphytic fitness mutants of pseudomonas syringae under controlled and field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, G.A.; Lindow, S.E. (Univ. of California, Berkeley, CA (United States))

    1994-10-01

    The epiphytic fitness of four Tn5 of Pseudomonas syringae that exhibited reduced epiphytic fitness in the laboratory was evaluated under field conditions. The mutants differed more from the parental strain under field conditions than under laboratory conditions, in their survival immediately following inoculation onto bean leaves and in the size of the epiphytic populations that they established at near-wild type rates, while the others exhibited reduced survival only in the warmest, driest conditions tested and grew epiphytically at reduced rates or, in the case of one mutant, not at all. The presence of the parental strain, B728a, did not influence the survival or growth of three of the mutants under field conditions; however, one mutant, an auxotroph, established larger populations in the presence of B728a than in its absence, possibly because of cross-feeding by By28a in planta. Experiments with B728a demonstrated that established epiphytic populations survived exposure of leaves to dry conditions better than newly inoculated cells did and that epiphytic survival was not dependent on the cell density in the inoculum. Three of the mutants behaved similarly to two nonpathogenic strains of P. syringae, suggesting that the mutants may be altered in traits that are missing or poorly expressed in naturally occurring nonpathogenic epiphytes. 58 refs., 5 figs., 3 tabs.

  14. Similarity in properties and mapping of three rec mutants of Haemophilus influenzae

    Energy Technology Data Exchange (ETDEWEB)

    Kooistra, J.; Setlow, J.K.

    1976-07-01

    Three Rec/sup -/ mutants of Haemophilus influenzae have been studied with respect to their transformability, ultraviolet and mitomycin C sensitivities, spontaneous and ultraviolet-induced deoxyribonucleic acid breakdown, inducibility of lysogens, and the linkage of the three mutations to a streptomycin resistance marker. The data indicate that the three mutations cause the same phenotypic changes, and that they are all on the same gene. Transformability of the mutants is different when two different media are used for competence development, although transformability with the two competence methods is not different in a Rec/sup -/ strain that is mutant at another gene.

  15. Glycoprotein processing in mutants of HSV-1 that induce cell fusion

    Energy Technology Data Exchange (ETDEWEB)

    Person, S.; Kousoulas, K.G.; Knowles, R.W.; Read, G.S.; Holland, T.C.; Keller, P.M.; Warner, S.C.

    1982-01-01

    The synthesis of viral-specified glycoproteins, and their appearance on cell surfaces, were compared for cells infected either with syncytial mutants of HSV-1 or with the parental strains from which the mutants were derived. The mutants MP and tsB5, representatives of two different viral genes that affect fusion, were employed in these studies. Cells infected with either mutant gave rise to reduce surface labeling of major viral-specified glycoproteins throughout infection relative to the parental strains. Putative glycoprotein precursors were synthesized in similar amounts throughout infection in mutant and wild-type infected cells. However, during a chase period after a pulse of labeling, fully glycosylated species of glycoproteins accumulated more slowly in mutant than in parent infected cells. The effect was clearly visible early in MP-infected cells and by 9 hr after infection for tsB5-infected cells, and increased thereafter. Apparently the decrease in appearance of glycoproteins on the cell surface of mutant-infected cells is due to a decrease in their rate of processing. 26 references, 7 figures.

  16. Properties of mutants of haemophilus influenzae deficient in ATP-dependent deoxyribonuclease

    Energy Technology Data Exchange (ETDEWEB)

    Setlow, J.K.

    1976-01-01

    Eight isogenic Haemophilus influenzae strains whose extracts lack ATP-dependent deoxyribonuclease activity (Add/sup -/ mutants) form three complementation and genetic linkage groups. Since there are known to be three subunits of the enzyme, these data suggest that each of the three genes specifies a different subunit. Gel electrophoresis of partially purified mutant extracts indicates that the smallest subunit is missing in one of the groups but is present in all the other mutants. The mutants are more sensitive to a variety of chemical agents than the wild type. The most sensitive mutants lack the ATPase activity associated with the enzyme. These strains exhibit aberrant incorporation of tritiated thymidine, which starts up more rapidly and shuts off sooner than in the wild type. An extracellular compound is responsible for most of this effect, in that wild type cells put into medium in which Add/sup -/ cells have been growing show a similar aberrant incorporation. The effect of these media can be mimicked by cyclic AMP and cyclic GMP, although millimolar concentrations are required. It is postulated that the Add/sup -/ mutants are more permeable to many substances than the wild type, partly because of the extracellular compound usually surrounding them, and the increased permeability might be responsible for the mutants' nonviability.

  17. Abnormal grooming activity in Dab1(scm) (scrambler) mutant mice.

    Science.gov (United States)

    Strazielle, C; Lefevre, A; Jacquelin, C; Lalonde, R

    2012-07-15

    Dab1(scm) mutant mice, characterized by cell ectopias and degeneration in cerebellum, hippocampus, and neocortex, were compared to non-ataxic controls for different facets of grooming caused by brief water immersions, as well as some non-grooming behaviors. Dab1(scm) mutants were strongly affected in their quantitative functional parameters, exhibiting higher starting latencies before grooming relative to non-ataxic littermates of the A/A strain, fewer grooming bouts, and grooming components of shorter duration, with an unequal regional distribution targeting almost totally the rostral part (head washing and forelimb licking) of the animal. Only bouts of a single grooming element were preserved. The cephalocaudal order of grooming elements appeared less disorganized, mutant and control mice initiating the grooming with head washing and forelimb licking prior to licking posterior parts. However, mutants differed from controls in that all their bouts were incomplete but uninterrupted, although intergroup difference for percentage of the incorrect transitions was not significant. In contrast to grooming, Dab1(scm) mice ambulated for a longer time. During walking episodes, they exhibited more body scratching than controls, possibly to compensate for the lack of licking different body parts. In conjunction with studies with other ataxic mice, these results indicate that the cerebellar cortex affects grooming activity and is consequently involved in executing various components, but not in its sequential organization, which requires other brain regions such as cerebral cortices or basal ganglia.

  18. atp mutants of Escherichia coli fail to grow on succinate due to a transport deficiency

    DEFF Research Database (Denmark)

    Boogerd, Fred; Boe, Lars; Michelsen, Ole

    1998-01-01

    Escherichia coli atp mutants, which lack a functional Hf-ATPase complex, are capable of growth on glucose but not on succinate or other C-4-dicarboxylates (Suc(-) phenotype). Suc(+) revertants of an atp deletion strain were isolated which were capable of growth on succinate even though they lack......) was expressed in trans, the Suc(-) phenotype of the atp deletion strain reverted to Suc(+), which shows that the reason why the E. coli atp mutant is unable to grow aerobically on C-4-dicarboxylates is insufficient transport capacity for these substrates....

  19. atp mutants of Escherichia coli fail to grow on succinate due to a transport deficiency

    DEFF Research Database (Denmark)

    Boogerd, Fred; Boe, Lars; Michelsen, Ole

    1998-01-01

    Escherichia coli atp mutants, which lack a functional Hf-ATPase complex, are capable of growth on glucose but not on succinate or other C-4-dicarboxylates (Suc(-) phenotype). Suc(+) revertants of an atp deletion strain were isolated which were capable of growth on succinate even though they lack......) was expressed in trans, the Suc(-) phenotype of the atp deletion strain reverted to Suc(+), which shows that the reason why the E. coli atp mutant is unable to grow aerobically on C-4-dicarboxylates is insufficient transport capacity for these substrates....

  20. Bacterial mutants for enhanced succinate production

    NARCIS (Netherlands)

    Baart, G.J.E.; Beauprez, J.J.R.; Foulquie, M.M.R.; Heijnen, J.J.; Maertens, J.

    2010-01-01

    The present invention relates to a method for obtaining enhanced metabolite production in micro-organisms, and to mutants and/or transformants obtained with said method. More particularly, it relates to bacterial mutants and/or transformants for enhanced succinate production, especially mutants and/