Sodium dodecyl sulfate-capillary gel electrophoresis of polyethylene glycolylated interferon alpha.

Science.gov (United States)

Na, Dong H; Park, Eun J; Youn, Yu S; Moon, Byung W; Jo, Yeong W; Lee, Sung H; Kim, Won-Bae; Sohn, Yeowon; Lee, Kang C

2004-02-01

Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) using a hydrophilic replaceable polymer network matrix was applied to characterize the polyethylene glycol(PEG)ylated interferon alpha (PEG-IFN). The SDS-CGE method resulted in a clearer resolution in both the PEG-IFN species and the native IFN species. The distribution profile of PEGylation determined by SDS-CGE was consistent with that obtained by SDS-polyacrylamide gel electrophoresis (PAGE) with Coomassie blue or barium iodide staining. The result was also compared using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. SDS-CGE was also useful for monitoring the PEGylation reaction to optimize the reaction conditions, such as reaction molar ratio. This study shows the potential of SDS-CGE as a new method for characterizing the PEGylated proteins with advantages of speed, minimal sample consumption and high resolution.

Sodium dodecyl benzene sulphonate mediated tautomerism of Eriochrome Black-T: Effect of charge transfer interaction

Science.gov (United States)

Ghosh, Sumit

2010-11-01

Interaction between anionic surfactant, sodium dodecyl benzene sulphonate, (SDBS) and an anionic dye Eriochrome Black-T, (EBT) has been investigated by visible spectroscopy, conductometry, dynamic light scattering and zeta potential measurements. Spectral changes of EBT observed on addition of SDBS indicate formation of quinone-hydrazone tautomer at pH 7.0, whereas in absence of SDBS this change appears at pH ˜ 9.45. However, at pH 7.0 this change in tautomerism is not observed in presence of sodium dodecyl sulphate (SDS). Experimental results indicate presence of charge transfer interaction between less stable quinone-hydrazone tautomer of EBT and SDBS molecules, which is confirmed using Benesi-Hildebrand and Scott equations.

Preparative isolation of a cytotoxic principle of a forest mushroom Suillus luteus by sodium dodecyl sulfate based "salting-in" countercurrent chromatography.

Science.gov (United States)

Yang, Zhi; Hu, Xueqian; Wu, Shihua

2016-02-01

In the course of screening new anticancer natural products, an edible forest mushroom Suillus luteus (L. Ex Franch). Gray was found to have potent cytotoxicity against several human cancer cells. However, the lipophilic sample made some countercurrent chromatography solvent systems emulsify, which caused difficulties in the separation of its cytotoxic components. Here, we found that the addition of an organic salt sodium dodecyl sulfate could efficiently shorten the settling time of the mushroom sample solutions by eliminating the emulsification of two-phase solvent systems. Moreover, we found that sodium dodecyl sulfate could play a new "salting-in" role and made the partition coefficients of the solutes decrease with the increased concentrations. Thus, a sodium dodecyl sulfate based salting-in countercurrent chromatography method has been successfully established for the first time for preparative isolation of a cytotoxic principle of the mushroom. The active component was identified as isosuillin. Whole results indicated that sodium dodecyl sulfate could be used as an efficient salting-in reagent for two-phase solvent system selection and targeted countercurrent chromatography isolation. It is very useful for current natural products isolation and drug discovery. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sodium Dodecyl Sulfate (SDS)-Loaded Nanoporous Polymer as Anti-Biofilm Surface Coating Material

DEFF Research Database (Denmark)

Li, Li; Molin, Søren; Yang, Liang

2013-01-01

-b-polydimethylsiloxane (1,2-PB-b-PDMS) block copolymer via chemical cross-linking of the 1,2-PB block followed by quantitative removal of the PDMS block. Sodium dodecyl sulfate (SDS) was loaded into the nanoporous 1,2-PB from aqueous solution. The SDS-loaded nanoporous polymer films were shown to block bacterial attachment...

Coupling Sodium Dodecyl Sulfate–Capillary Polyacrylamide Gel Electrophoresis with MALDI-TOF-MS via a PTFE Membrane

Science.gov (United States)

Lu, Joann J.; Zhu, Zaifang; Wang, Wei; Liu, Shaorong

2011-01-01

Sodium dodecyl sulfate (SDS)–polyacrylamide gel electrophoresis (PAGE) is a fundamental analytical technique for proteomic research, and SDS–capillary gel electrophoresis (CGE) is its miniaturized version. Compared to conventional slab-gel electrophoresis, SDS-CGE has many advantages such as increased separation efficiency, reduced separation time and automated operation. SDS-CGE is not widely accepted in proteomic research primarily due to the difficulties in identifying the well-resolved proteins. MALDI–TOF–MS is an outstanding platform for protein identifications. Coupling the two would solve the problem but is extremely challenging because the MS detector has no access to the SDS-CGE resolved proteins and the SDS interferes with MS detection. In this work we introduce an approach to address these issues. We discover that poly(tetrafluoroethylene) (PTFE) membranes are excellent materials for collecting SDS-CGE separated proteins. We demonstrate that we can wash off the SDS bound to the collected proteins and identify these proteins on-membrane with MALDI-TOF-MS. We also show that we can immunoblot and Coomassie-stain the proteins collected on these membranes. PMID:21309548

Cation modulation of hemoglobin interaction with sodium n-dodecyl sulphate (SDS) iv: magnesium modulation at pH 7.20

OpenAIRE

Ali Akbar Moosavi-Movahedi; Ferdinand C. Chilaka; Charles O. Nwamba

2016-01-01

We investigate the interaction of Mg2+ (0–2.30 mM) and sodium n-dodecyl sulfate (SDS) with hemoglobins (Hbs) A and S at pH 7.20. SDS was used to model both membranes (0.60 mM SDS) and proteases (5.0 mM SDS). Via UV-visible spectroscopy, second derivative and difference second derivative spectroscopy, we interrogated for difference(s) in the interaction of these ligands with the proteins that can account for the HbS resistance to malaria parasite while been prone to sickling. Our results show ...

Effects of sodium dodecyl sulfate of polyphenoloxidase

International Nuclear Information System (INIS)

Moore, B.M.; Flurkey, W.H.

1989-01-01

The effects of sodium dodecyl sulfate (SDS) on the enzymatic and physical characteristics of purified broad bean polyphenoloxidase (PPO) were examined. A sigmoidal increase in PPO activation was observed with increasing SDS concentrations. Half maximal activation occurred at .9 mM SDS well below the CMC of 3.5 mM. No apparent changes in the Km for catechol, pH optimum, of I 50 for tropolone were observed in the presence vs absence of SDS. Thermal inactivation and binding of 14 C dopa increased in the presence of SDS. Analytical ultracentrifugation and HPLC-SEC indicated that SDS did not change the apparent size of the PPO under nondenaturing conditions. Scanning fluorescence spectroscopy showed an increase in intrinsic trp/tyr fluorescence at approximately the same concentration in which SDS activation began. Further addition of SDS caused a large increase in intrinsic fluorescence. These results suggest the SDS causes an apparent conformational change induced by SDS binding which leads to enzyme activation

Electrophoretic analysis of proteinases in sodium dodecyl sulfate-polyacrylamide gels containing copolymerized radiolabeled protein substrates: Application to proenkephalin processing enzymes

Energy Technology Data Exchange (ETDEWEB)

Irvine, J.W.; Roberts, S.F.; Lindberg, I. (Louisiana State Univ. Medical Center, New Orleans (USA))

1990-10-01

A novel method is described for the zymographic analysis of proteinases in sodium dodecyl sulfate-polyacrylamide gels containing copolymerized radiolabeled protein substrates such as ({sup 35}S)methionine-labeled proenkephalin or {sup 125}I-labeled proinsulin. After electrophoresis the enzyme is reactivated and cleaves the radiolabeled in situ substrate into smaller peptides. These small peptides are able to diffuse out of the gel, leaving clear areas against a dark background when visualized by autoradiography. The technique can be used to detect as little as 200 fg of trypsin using only 50 ng (1.25 microCi) of ({sup 35}S)proenkephalin. Soluble- and membrane-bound adrenal trypsin-like enzyme were isolated from bovine adrenal chromaffin granules. Both proteinases cleaved ({sup 35}S)methionine-labeled proenkephalin but not {sup 125}I-labeled proinsulin. Moreover, both had a Mr of approximately 30,000. The potential of this technique for general use is discussed. An additional method using the synthetic fluorogenic substrate t-butoxycarbonyl Glu-Lys-Lys aminomethylcoumarin is also described.

Background-free, high sensitivity staining of proteins in one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gels using a luminescent ruthenium complex.

Science.gov (United States)

Berggren, K; Chernokalskaya, E; Steinberg, T H; Kemper, C; Lopez, M F; Diwu, Z; Haugland, R P; Patton, W F

2000-07-01

SYPRO Ruby dye is a permanent stain comprised of ruthenium as part of an organic complex that interacts noncovalently with proteins. SYPRO Ruby Protein Gel Stain provides a sensitive, gentle, fluorescence-based method for detecting proteins in one-dimensional and two-dimensional sodium dodecyl sulfate-polyacrylamide gels. Proteins are fixed, stained from 3h to overnight and then rinsed in deionized water or dilute methanol/acetic acid solution for 30 min. The stain can be visualized using a wide range of excitation sources commonly used in image analysis systems including a 302 nm UV-B transilluminator, 473 nm second harmonic generation (SHG) laser, 488 nm argon-ion laser, 532 nm yttrium-aluminum-garnet (YAG) laser, xenon arc lamp, blue fluorescent light bulb or blue light-emitting diode (LED). The sensitivity of SYPRO Ruby Protein Gel Stain is superior to colloidal Coomassie Brilliant Blue (CBB) stain or monobromobimane labeling and comparable with the highest sensitivity silver or zinc-imidazole staining procedures available. The linear dynamic range of SYPRO Ruby Protein Gel stain extends over three orders of magnitude, which is vastly superior to silver, zinc-imidazole, monobromobimane and CBB stain. The fluorescent stain does not contain superfluous chemicals (formaldehyde, glutaraldehyde, Tween-20) that frequently interfere with peptide identification in mass spectrometry. While peptide mass profiles are severely altered in protein samples prelabeled with monobromobimane, successful identification of proteins by peptide mass profiling using matrix-assisted laser desorption/ionization mass spectrometry was easily performed after protein detection with SYPRO Ruby Protein Gel stain.

Activation of Recombinantly Expressed l-Amino Acid Oxidase from Rhizoctonia solani by Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Katharina Hahn

2017-12-01

Full Text Available l-Amino acid oxidases (l-AAO catalyze the oxidative deamination of l-amino acids to the corresponding α-keto acids. The non-covalently bound cofactor FAD is reoxidized by oxygen under formation of hydrogen peroxide. We expressed an active l-AAO from the fungus Rhizoctonia solani as a fusion protein in E. coli. Treatment with small amounts of the detergent sodium dodecyl sulfate (SDS stimulated the activity of the enzyme strongly. Here, we investigated whether other detergents and amphiphilic molecules activate 9His-rsLAAO1. We found that 9His-rsLAAO1 was also activated by sodium tetradecyl sulfate. Other detergents and fatty acids were not effective. Moreover, effects of SDS on the oligomerization state and the protein structure were analyzed. Native and SDS-activated 9His-rsLAAO1 behaved as dimers by size-exclusion chromatography. SDS treatment induced an increase in hydrodynamic radius as observed by size-exclusion chromatography and dynamic light scattering. The activated enzyme showed accelerated thermal inactivation and an exposure of additional protease sites. Changes in tryptophan fluorescence point to a more hydrophilic environment. Moreover, FAD fluorescence increased and a lower concentration of sulfites was sufficient to form adducts with FAD. Taken together, these data point towards a more open conformation of SDS-activated l-amino acid oxidase facilitating access to the active site.

A comparison study between sodium dodecyl sulfate and sodium dodecyl sulfonate with respect to the thermodynamic properties, micellization, and interaction with poly(ethylene glycol) in aqueous solutions

International Nuclear Information System (INIS)

Sadeghi, Rahmat; Shahabi, Somayyeh

2011-01-01

Graphical abstract: Apparent molar volume against molality: o, ·, and Δ, respectively in water, (1 and 4) wt% PEG solution at 293.15 K; x, Δ, and lozenge, respectively in water, (1 and 4) wt% PEG solution at 313.15 K. Research highlights: → C 12 H 25 SO 3 Na(SDSn) was seen to interact with PEG more weakly than C 12 H 25 SO 4 Na(SDS). → The constraints on molecular mobility of SDS micelles are larger than those of SDSn. → Entropy change on micellization for SDSn is larger than those for SDS. → Micelle formation of SDS is less endothermic and more spontaneous than that of SDSn. → Micelles of SDS have smaller aggregation number than that of SDSn. - Abstract: The density, sound velocity, and conductivity measurements were performed on aqueous solutions of sodium dodecyl sulfate (C 12 H 25 SO 4 Na) or sodium dodecyl sulfonate (C 12 H 25 SO 3 Na) in the absence and presence of poly(ethylene glycol) (PEG) at different temperatures. Changes in the apparent molar volumes and isentropic compressibilities upon micellization were derived using a pseudophase-transition approach and the infinite dilution apparent molar properties of the monomer and micellar form of C 12 H 25 SO 4 Na and C 12 H 25 SO 3 Na were determined. Variations of the critical micelle concentrations (CMCs) of both surfactants in the solutions investigated with temperature were obtained from which thermodynamic parameters of micellization were estimated. It was found that at low temperature the micelle formation process is endothermic and therefore, this process must be entropically driven. However, upon increasing the temperature, the enthalpic factor becomes more significant and, at temperatures higher than 303.15 K the micellization is enthalpy driven. The interactions between C 12 H 25 SO 4 Na/C 12 H 25 SO 3 Na and PEG were studied and it was found that sodium alkyl sulfonates were seen to interact more weakly than their sulfate analogues.

Study of total seed proteins pattern of sesame (sesamum indicum l.) landraces via sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page)

International Nuclear Information System (INIS)

Akbar, F.; Shinwari, Z.K.

2012-01-01

The sesame (Sesamum indicum L.) germplasm, comprising of 105 accessions was characterized for total seed storage proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The germplasm was collected from diverse agro-ecological regions of Pakistan. To our information, no studies have yet been carried out in Pakistan on the genetic evaluation of sesame genotypes based on total seed protein. Total seed proteins were electrophoretically separated on 12% polyacrylamide gels by standard protocols. A total of 20 polypeptide bands were observed, of which 14 (70%) were polymorphic and 6 (30%) were monomorphic, with molecular weight ranging from 13.5 to 100 kDa. Six bands i.e., 7, 11, 12, 15, 16 and 18 were common in all genotypes. Similarity coefficients varied fro m 0.50 to 1.00. The dendrogram based on dissimilarity matrix using unweighted pair group method with arithmetic averages (UPGMA) separated all sesame accessions into three main groups i.e., A, B, C, comprising 89, 14 and 2 genotypes, respectively. Overall a low to medium level of genetic variability was observed for SDS-PAGE (single dimension). As SDS-PAGE alone did not reveal high level of genetic variability, hence 2-D gel electrophoresis along with other advanced type DNA markers and more number of sesame accessions from all over the country are recommended for the future genetic evaluation. Our investigation will significantly support the classification, development, genetic evaluation and conservation of sesame germplasm in Pakistan. (author)

Study of total seed proteins pattern of sesame (sesamum indicum l.) landraces via sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page)

Energy Technology Data Exchange (ETDEWEB)

Akbar, F; Shinwari, Z K [Quaid-e-Azam University, Islamabad (Pakistan). Dept. of Biotechnology; Yousif, N; Masood, M S [Institute of Agri-Biotechnology and Genetic Resources, Islamabad (Pakistan)

2012-11-15

The sesame (Sesamum indicum L.) germplasm, comprising of 105 accessions was characterized for total seed storage proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The germplasm was collected from diverse agro-ecological regions of Pakistan. To our information, no studies have yet been carried out in Pakistan on the genetic evaluation of sesame genotypes based on total seed protein. Total seed proteins were electrophoretically separated on 12% polyacrylamide gels by standard protocols. A total of 20 polypeptide bands were observed, of which 14 (70%) were polymorphic and 6 (30%) were monomorphic, with molecular weight ranging from 13.5 to 100 kDa. Six bands i.e., 7, 11, 12, 15, 16 and 18 were common in all genotypes. Similarity coefficients varied fro m 0.50 to 1.00. The dendrogram based on dissimilarity matrix using unweighted pair group method with arithmetic averages (UPGMA) separated all sesame accessions into three main groups i.e., A, B, C, comprising 89, 14 and 2 genotypes, respectively. Overall a low to medium level of genetic variability was observed for SDS-PAGE (single dimension). As SDS-PAGE alone did not reveal high level of genetic variability, hence 2-D gel electrophoresis along with other advanced type DNA markers and more number of sesame accessions from all over the country are recommended for the future genetic evaluation. Our investigation will significantly support the classification, development, genetic evaluation and conservation of sesame germplasm in Pakistan. (author)

Quantification of Whey Protein Content in Infant Formulas by Sodium Dodecyl Sulfate-Capillary Gel Electrophoresis (SDS-CGE): Single-Laboratory Validation, First Action 2016.15.

Science.gov (United States)

Feng, Ping; Fuerer, Christophe; McMahon, Adrienne

2017-03-01

Protein separation by sodium dodecyl sulfate-capillary gel electrophoresis, followed by UV absorption at 220 nm, allows for the quantification of major proteins in raw milk. In processed dairy samples such as skim milk powder (SMP) and infant formulas, signals from individual proteins are less resolved, but caseins still migrate as one family between two groups of whey proteins. In the first group, α-lactalbumin and β-lactoglobulin migrate as two distinct peaks. Lactosylated adducts show delayed migration times and interfere with peak separation, but both native and modified forms as well as other low-MW whey proteins still elute before the caseins. The second group contains high-MW whey proteins (including bovine serum albumin, lactoferrin, and immunoglobulins) and elutes after the caseins. Caseins and whey proteins can thus be considered two distinct nonoverlapping families whose ratio can be established based on integrated areas without the need for a calibration curve. Because mass-to-area response factors for whey proteins and caseins are different, an area correction factor was determined from experimental measurement using SMP. Method performance assessed on five infant formulas showed RSDs of 0.2-1.2% (within day) and 0.5-1.1% (multiple days), with average recoveries between 97.4 and 106.4% of added whey protein. Forty-three different infant formulas and milk powders were analyzed. Of the 41 samples with manufacturer claims, the measured whey protein content was in close agreement with declared values, falling within 5% of the declared value in 76% of samples and within 10% in 95% of samples.

Analysis of aqueous humour in uveitis by high performance liquid chromatography and sodium dodecyl sulphate-polyacrylamide gel electrophoresis

NARCIS (Netherlands)

Murray, P. I.; Hoekzema, R.; Luyendijk, L.; Kijlstra, A.

1992-01-01

Aqueous humour from patients with Fuchs' heterochromic cyclitis (FHC) and other types of uveitis was analysed by high performance liquid chromatography (HPLC) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Using HPLC, the number of peaks and their respective elution times

Electrochemistry of Cytochrome P450 BM3 in Sodium Dodecyl Sulfate Films

Science.gov (United States)

Udit, Andrew K.; Hill, Michael G.; Gray, Harry B.

2008-01-01

Direct electrochemistry of the cytochrome P450 BM3 heme domain (BM3) was achieved by confining the protein within sodium dodecyl sulfate (SDS) films on the surface of basal-plane graphite (BPG) electrodes. Cyclic voltammetry revealed the heme FeIII/II redox couple at −330 mV (vs. Ag/AgCl, pH 7.4). Up to 10 V/s, the peak current was linear with scan rate, allowing us to treat the system as surface-confined within this regime. The standard heterogeneous rate constant determined at 10 V/s was estimated to be 10 s−1. Voltammograms obtained for the BM3-SDS-BPG system in the presence of dioxygen exhibited catalytic waves at the onset of FeIII reduction. The altered heme reduction potential of the BM3-SDS-graphite system indicates that SDS is likely bound in the enzyme active-site region. Compared to other P450-surfactant systems, we find redox potentials and electron transfer rates that differ by ~ 100 mV and > 10-fold, respectively, indicating that the nature of the surfactant environment has a significant effect on the observed heme redox properties. PMID:17129070

Characterization of Sm14 related components in different helminths by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting analysis

Directory of Open Access Journals (Sweden)

Nilton Thaumaturgo

2002-10-01

Full Text Available Sm14 was the first fatty acid-binding protein homologue identified in helminths. Thereafter, members of the same family were identified in several helminth species, with high aminoacid sequence homology between them. In addition, immune crossprotection was also reported against Fasciola hepatica infection, in animals previously immunized with the Schistosoma mansoni vaccine candidate, r-Sm14. In the present study, data on preliminary sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting analysis of nine different helminth extracts focusing the identification of Sm14 related proteins, is reported. Out of these, three extracts - Ascaris suum (males and females, Echinostoma paraensei, and Taenia saginata - presented components that comigrated with Sm14 in SDS-PAGE, and that were recognized by anti-rSm14 policlonal serum, in Western blotting tests.

A comparison study between sodium dodecyl sulfate and sodium dodecyl sulfonate with respect to the thermodynamic properties, micellization, and interaction with poly(ethylene glycol) in aqueous solutions

Energy Technology Data Exchange (ETDEWEB)

Sadeghi, Rahmat, E-mail: rsadeghi@uok.ac.ir [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Shahabi, Somayyeh [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2011-09-15

Graphical abstract: Apparent molar volume against molality: o, {center_dot}, and {Delta}, respectively in water, (1 and 4) wt% PEG solution at 293.15 K; x, {Delta}, and lozenge, respectively in water, (1 and 4) wt% PEG solution at 313.15 K. Research Highlights: > C{sub 12}H{sub 25}SO{sub 3}Na(SDSn) was seen to interact with PEG more weakly than C{sub 12}H{sub 25}SO{sub 4}Na(SDS). > The constraints on molecular mobility of SDS micelles are larger than those of SDSn. > Entropy change on micellization for SDSn is larger than those for SDS. > Micelle formation of SDS is less endothermic and more spontaneous than that of SDSn. > Micelles of SDS have smaller aggregation number than that of SDSn. - Abstract: The density, sound velocity, and conductivity measurements were performed on aqueous solutions of sodium dodecyl sulfate (C{sub 12}H{sub 25}SO{sub 4}Na) or sodium dodecyl sulfonate (C{sub 12}H{sub 25}SO{sub 3}Na) in the absence and presence of poly(ethylene glycol) (PEG) at different temperatures. Changes in the apparent molar volumes and isentropic compressibilities upon micellization were derived using a pseudophase-transition approach and the infinite dilution apparent molar properties of the monomer and micellar form of C{sub 12}H{sub 25}SO{sub 4}Na and C{sub 12}H{sub 25}SO{sub 3}Na were determined. Variations of the critical micelle concentrations (CMCs) of both surfactants in the solutions investigated with temperature were obtained from which thermodynamic parameters of micellization were estimated. It was found that at low temperature the micelle formation process is endothermic and therefore, this process must be entropically driven. However, upon increasing the temperature, the enthalpic factor becomes more significant and, at temperatures higher than 303.15 K the micellization is enthalpy driven. The interactions between C{sub 12}H{sub 25}SO{sub 4}Na/C{sub 12}H{sub 25}SO{sub 3}Na and PEG were studied and it was found that sodium alkyl sulfonates were seen

Immobilization of surface active compounds on polymer supports using glow discharge processess. 1. Sodium dodecyl sulfate on poly(propylene)

NARCIS (Netherlands)

Terlingen, J.G.A.; Terlingen, Johannes G.A.; Feijen, Jan; Hoffman, Allan S.

1993-01-01

A new method has been developed in which a reversibly adsorbed layer of a surfactant (sodium dodecyl sulfate, SDS) is covalently immobilized in one step onto a hydrophobic substrate (poly(propylene), PP) by applying an argon plasma treatment. The adsorption of SDS from aqueous solutions onto PP

Studies of the effect of ethanol and sodium chloride on the micellization of sodium dodecyl sulfate by gel filtration

Energy Technology Data Exchange (ETDEWEB)

Suzuki, H.

1976-06-01

The effects of the addition of ethanol and sodium chloride to aqueous solutions of sodium dodecyl sulfate (SDS) were studied by the gel-filtration method. With an increase in the concentration of ethanol, the CMC decreased and then increased after passing a minimum, while the micellar weight increased and then decreased, showing a corresponding maximum. Above about 40 vol percent ethanol, no micelle formation was observed. The micellar weight and aggregation number in the presence of ethanol were measured in the SDS concentration range of a constant elution rate of micelles. A decrease in the CMC and an increase in the micellar weight of SDS were observed with an increase in the concentration of NaCl from 0 to 10 mmol/l. The gel-filtration study enabled us to make a direct experimental confirmation of the effects of ethanol and NaCl on the micelle formation of SDS.

Thermodynamic solution properties of pefloxacin mesylate and its interactions with organized assemblies of anionic surfactant, sodium dodecyl sulphate

International Nuclear Information System (INIS)

Usman, Muhammad; Rashid, Muhammad Abid; Mansha, Asim; Siddiq, Mohammad

2013-01-01

Graphical abstract: - Highlights: • Free energy of adsorption is more negative than free energy of micellization. • Micellization becomes more spontaneous at high temperature. • There is strong interaction between PFM and SDS. - Abstract: This manuscript reports the physicochemical behavior of antibiotic amphiphilic drug pefloxacin mesylate (PFM) and its interaction with anionic surfactant, sodium dodecyl sulfate (SDS). The data of surface tension and electrical conductivity are helpful to detect the CMC as well as to calculate surface parameters, i.e. surface pressure, π, surface excess concentration, Γ, area per molecule of drug and standard Gibbs free energy of adsorption, ΔG ads and thermodynamic parameters like standard free energy of micellization, ΔG m , standard enthalpy of micellization, ΔH m and standard entropy of micellization, ΔS m . The interaction of this drug with anionic surfactant, sodium dodecyl sulfate (SDS) was studied by electrical conductivity and UV/visible spectroscopy. This enabled us to compute the values of partition coefficient (K x ), free energy of partition, ΔG p , binding constant, K b , free energy of binding, ΔG b , number of drug molecules per micelle, n, and thermodynamic parameters of drug–surfactant interaction

ISOLATION OF EGG DROP SYNDROME VIRUS AND ITS MOLECULAR CHARACTERIZATION USING SODIUM DODECYL SULPHATE POLYACRYLAMIDE GEL ELECTROPHORESIS

Directory of Open Access Journals (Sweden)

M. H. Rasool, S. U. Rahman and M. K. Mansoor

2005-10-01

Full Text Available Six isolates of egg drop syndrome (EDS virus were recovered from five different outbreaks of EDS in commercial laying hens in and around Faisalabad. The aberrant eggs were fed to the susceptible laying hens for experimental induction of infection. The samples from infected birds (egg washing, cloacal swabs, oviducts and spleens were collected, processed and inoculated into 11-day old duck embryos. The presence of virus in harvested allanto-amniotic fluid was monitored by spot and microhaemagglutination tests and confirmed by haemagglutination inhibition and agar gel precipitation tests. The EDS virus grew well in duck embryos and agglutinated only avian but not mammalian red blood cells. These isolates were purified through velocity density gradient centrifugation. Protein concentration was determined through Lowry method and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE was conducted by loading 300 µg protein concentration on 12.5% gel using discontinuous buffer system. All the six isolates showed 13 polypeptides, which were identical to those described in the referral EDS-76 virus (strain-127. The molecular weights of the polypeptides ranged from 6.5 KDa to 126 KDa.

A Novel Method for Detection of Glycoproteins on Sodium Dodecyl Sulphate Polyacrylamide Gel Using Radio-Iodinated Tyrosine

DEFF Research Database (Denmark)

Nalla, Amarnadh; Draz, Hossam M.; Dole, Anita

2009-01-01

The aim of this study is to develop a novel method for detection of glycoproteins on polyacrylamide gel. In this method, radio-iodinated-tyrosine (125I-tyrosine) was conjugated to glycoprotein by schiff's base mechanism on the sodium dodecyl sulfate- polyacrylamide gel. Ovalbumin and Concanavalin...... of glycoproteins using 125I-tyrosine selectively detected ovalbumin. Present results showed that MPD enhanced glycoprotein detection method can be used as a sensitive tool for the detection of glycoproteins on polyacrylamide gel...

Detection of metalloproteins in human liver cytosol by synchrotron radiation X-ray fluorescence after sodium dodecyl sulphate polyacrylamide gel electrophoresis

International Nuclear Information System (INIS)

Gao Yuxi; Chen Chunying; Zhang Peiqun; Chai Zhifang; He Wei; Huang Yuying

2003-01-01

An improved method of analysis of metals in protein bands with synchrotron radiation X-ray fluorescence (SRXRF) after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation is introduced and applied to human liver cytosol. Through a step of drying the gel before SRXRF determination, the continuous background resulting mainly from the Compton-scattering of X-rays by the gel matrix was substantially reduced, and the detection of biological trace elements, such as Cu, Fe, and Zn in protein bands was thereby made possible. With the new procedure, six Zn-containing proteins with molecular weights (MWs) of 17.5, 20.5, 27, 35, 55, and 63 kDa, respectively were found in human liver cytosol, among which the 63 kDa Zn-containing band was shown to be the dominant form of zinc. In addition, at least four Fe containing proteins with MWs of 20, 23, 43, and 83.5 kDa, respectively, were present in the samples. The metal contents in some metalloproteins, such as the 63 kDa Zn-containing protein, the 23 and 83.5 kDa Fe-containing proteins, and a 22 kDa Cu-containing protein were more closely related to the metal level in the sample. It is demonstrated that the procedure could be widely used to further investigate metal-binding proteins in biological samples

Pretreatment of clinical specimens with sodium dodecyl (lauryl) sulfate is not suitable for the mycobacteria growth indicator tube cultivation method.

OpenAIRE

Pfyffer, G E; Welscher, H M; Kissling, P

1997-01-01

When using the Mycobacteria Growth Indicator Tube (MGIT), pretreatment of clinical specimens with N-acetyl-L-cysteine-NaOH is recommended by the manufacturer. Processing of clinical specimens (n = 1,000) with sodium dodecyl (lauryl) sulfate-NaOH resulted in both poor recovery and delayed mean time to detection of acid-fast bacilli. Values were comparable to those obtained on solid media.

Evidence of β-sheet structure induced kinetic stability of papain upon thermal and sodium dodecyl sulphate denaturation

Directory of Open Access Journals (Sweden)

Rašković Brankica

2015-01-01

Full Text Available Papain is a protease that consists of α-helical and β-sheet domains which unfold almost independently. Both, papain considerable thermal stability and sodium dodecyl sulphate (SDS resistance have been shown. However, the ability of each domain to unfold upon thermal and SDS denaturation has never been studied. This work shows that fruit papain has slightly higher thermal inactivation resistance when it is compared to stem papain with rather high activation energy (Ea of 223 ± 16 kJmol-1 and Tm50 value of 79 ± 2 °C. SDS resistance of fruit papain was estimated by SDS-PAGE analysis and activity staining. It has been noted that, in the presence of SDS, unless heat energy was applied in order to unfold papain, the protein remained active. Furthermore, it has been proven via Fourier transform infrared spectroscopy (FT-IR that α-helical domain of fruit papain is more prone to unfolding at elevated temperatures and in the presence of SDS then β-sheet rich domain. Thermal denaturation of papain without detergent present led to accelerated formation of aggregation specific intermolecular β-sheets as compared to native protein. Presented results are both, of fundamental and application importance. [Projekat Ministarstva nauke Republike Srbije, br. 172049

Molecular dynamics simulations of the effects of sodium dodecyl sulfate on lipid bilayer

International Nuclear Information System (INIS)

Xu Bin; Lin Wen-Qiang; Wang Xiao-Gang; Zhou Guo-Quan; Chen Jun-Lang; Zeng Song-wei

2017-01-01

Molecular dynamics simulations have been performed on the fully hydrated lipid bilayer with different concentrations of sodium dodecyl sulfate (SDS). SDS can readily penetrate into the membrane. The insertion of SDS causes a decrease in the bilayer area and increases in the bilayer thickness and lipid tail order, when the fraction of SDS is less than 28%. Through calculating the binding energy, we confirm that the presence of SDS strengthens the interactions among the DPPC lipids, while SDS molecules act as intermedia. Both the strong hydrophilic interactions between sulfate and phosphocholine groups and the hydrophobic interactions between SDS and DPPC hydrocarbon chains contribute to the tight packing and ordered alignment of the lipids. These results are in good agreement with the experimental observations and provide atomic level information that complements the experiments. (paper)

SODIUM DI-N-DODECYL PHOSPHATE VESICLES IN AQUEOUS-SOLUTION - EFFECTS OF ETHANOL, PROPANOL, AND TETRAHYDROFURAN ON THE GEL TO LIQUID-PHASE TRANSITION

NARCIS (Netherlands)

BLANDAMER, MJ; BRIGGS, B; BUTT, MD; WATERS, M; CULLIS, PM; ENGBERTS, JBFN; HOEKSTRA, D; MOHANTY, RK

1994-01-01

For aqueous solutions containing vesicles formed by sodium di-n-dodecyl phosphate, the gel to liquid-crystal transition occurs near 35 degrees C, the temperature T-m. When ethanol is added, T-m decreases, but the scan shows evidence of several transitions as more alcohol is added. The effect of

The Initial Comparison Study of Sodium Lignosulfonate, Sodium Dodecyl Benzene Sulfonate, and Sodium p-Toluene Sulfonate Surfactant for Enhanced Oil Recovery

Science.gov (United States)

Khoirul Anas, Argo; Iman Prakoso, Nurcahyo; Sasvita, Dilla

2018-04-01

Surfactant (surface active agent) exhibit numerous interesting properties that enable their use as additional component in mobilising of residual oil from capillary pore after secondary recovery process using gas injection and water flooding. In this study, Sodium Lignosulfonate (SLS) surfactant was successfully synthesized by applying batch method using lignin from oil palm empty fruit bunches as precursor. Furthermore, its performance in reducing interfacial tension of crude oil and formation water colloidal system was compared with commercial available surfactant including Sodium Dodecyl Benzene Sulfonate (SDBS) and Sodium p-Toluene Sulfonate (SpTS). The synthesized SLS surfactant was characterized by using Fourier Transform Infrared (FTIR) spectroscopy. Meanwhile, its performance in reducing interfacial tension of crude oil and formation water colloidal system was analyzed by using compatibility test, phase behaviour analysis, and interfacial tension (IFT) measurement. The compatibility test shows that SLS, SDBS, and SpTS surfactants were compatible with formation water. In addition, the phase behaviour analysis shows that SLS surfactant was better than SpTS surfactant, while SDBS surfactant generates the highest performance proved by the best microemulsion formation resulted by SDBS. Furthermore, the optimum concentration of SLS, SDBS, and SpTS surfactants in reducing the interfacial tension of crude oil and formation water was 1.0%. The IFT measurement indicates that the performance of SLS with the value of 1.67 mN/m was also better than SpTS surfactant with the value of 3.59 mN/m. Meanwhile, SDBS surfactant shows the best performance with the IFT value of 0.47 mN/m.

Determination of albumins by its quenching effect on the fluorescence of Tb3+-oxolinic acid complex in presence of sodium dodecyl sulphate

International Nuclear Information System (INIS)

Wu Xia; Zheng Jinhua; Guo Changying; Yang Jinghe; Ding Honghong; Hu Zhiyong; Li Chao

2007-01-01

It is found that the fluorescence intensity of Tb 3+ -oxolinic acid (OA) complex can be greatly quenched by albumins in sodium dodecyl sulphate (SLS). Under optimum conditions, the quenched fluorescence intensity is in proportion to the concentration of proteins in the range of 5.0x10 -8 -1.0x10 -5 g ml -1 for bovine serum albumin (BSA), 1.0x10 -7 -1.0x10 -5 g ml -1 for human serum albumin (HSA) and 4.0x10 -7 -1.0x10 -5 g ml -1 for egg albumin (EA). Their detection limits (S/N=3) are 2.1x10 -8 , 2.5x10 -8 and 5.0x10 -8 g ml -1 , respectively. In addition, the interaction mechanism is also investigated

Cation modulation of hemoglobin interaction with sodium n-dodecyl sulphate (SDS iv: magnesium modulation at pH 7.20

Directory of Open Access Journals (Sweden)

Ali Akbar Moosavi-Movahedi

2016-03-01

Full Text Available We investigate the interaction of Mg2+ (0–2.30 mM and sodium n-dodecyl sulfate (SDS with hemoglobins (Hbs A and S at pH 7.20. SDS was used to model both membranes (0.60 mM SDS and proteases (5.0 mM SDS. Via UV-visible spectroscopy, second derivative and difference second derivative spectroscopy, we interrogated for difference(s in the interaction of these ligands with the proteins that can account for the HbS resistance to malaria parasite while been prone to sickling. Our results show that Mg2+ interaction with the proteins lowered the HbS oxygen affinity in comparison with the HbA. Additionally, [SDS]-protein interactions resulted in oxoferryl heme species formation that was prominent for the HbA and highly diminished for the HbS. [Mg2+] introduction to the [SDS]-protein mixture, however decreased the concentration of denatured protein species. The [Mg2+]-[SDS]-protein interactions suggest that while ionic or coulomb interactions for the HbA, in the presence of the surfactants, are [Mg2+] dependent, those of the HbS are not. Furthermore, hydrophobicity is a crucial force for the HbS interaction at neutral pH and is little-masked by ionic, electrostatic or coulombic interactions. In conclusion, at physiological pH, the Mg-SDS interaction decreased the HbS denaturation in comparison to the HbA.

Benzalkonium chloride neutralizes the irritant effect of sodium dodecyl sulfate.

Science.gov (United States)

McFadden, J P; Holloway, D B; Whittle, E G; Basketter, D A

2000-11-01

When benzalkonium chloride (BKC), a cationic surfactant, is added to sodium dodecyl sulfate (SDS), an anionic surfactant, and used in patch testing, on the basis of their known physicochemical interaction, it is possible to predict that there will be a tendency towards a reduction in the expected irritant response when compared to SDS alone. The aim of this study was to investigate whether BKC could reduce the irritant response to SDS when applied after the SDS exposure. 54 non-atopic adult volunteers were recruited for the study. 20% SDS was applied for 2 h under occlusion. 1% BKC was then applied to the same site. Various controls, including SDS application followed by water for 2 h, were included. The irritant reaction was assessed at 24 h and 48 h. 40 of the 54 subjects had some reaction when SDS was applied for 2 h followed by either benzalkonium chloride or water control under occlusion. In comparison to water control, where BKC was applied after SDS, 20 of the 40 responders had a weaker reaction but only 4 had a stronger response. This study shows that BKC applied to skin exposed to SDS attenuates the resulting irritant reaction.

Influence of sodium dodecyl sulfate concentration on the photocatalytic activity and dielectric properties of intercalated sodium dodecyl sulfate into Zn–Cd–Al layered double hydroxide

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Abdullah Ahmed Ali, E-mail: abdullah2803@gmail.com [Department of Physics, Faculty of Applied Science, Thamar University, Dhamar 87246 (Yemen); Talib, Zainal Abidin [Department of Physics, Faculty of Science, Universiti Putra Malaysia, UPM, Serdang, Selangor 43400 (Malaysia); Hussein, Mohd Zobir [Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, UPM, Serdang, Selangor 43400 (Malaysia)

2015-02-15

Highlights: • Zn–Cd–Al–LDH–DS were synthesized with different SDS concentrations. • Photocatalytic activity of samples was improved by increasing SDS concentration. • Dielectric response of LDH can be described by anomalous low frequency dispersion. • The dc conductivity values were calculated for Zn–Cd–Al–LDH–DS samples. • ESR spectra exhibited the successful intercalation of DS molecule into LDH gallery. - Abstract: Sodium dodecyl sulfate (SDS) has been successfully intercalated into Zn–Cd–Al–LDH precursor with different SDS concentrations (0.2, 0.3, 0.4, 0.5 and 1 mol L{sup −1}) using the coprecipitation method at (Zn{sup 2+} + Cd{sup 2+})/Al{sup 3+} molar ratio of 13 and pH 8. The structural, morphological, texture and composition properties of the synthesized (Zn–Cd–Al–LDH–DS) nanostructure were investigated using powder X-ray diffraction (PXRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR), respectively. The photocatalytic activity of these materials was developed by increasing the concentration of intercalated SDS. The absorbance spectra have been used to detect an anion in the LDH interlayer before and after the intercalation process, which confirmed the presence of the dodecyl sulfate (DS{sup −}) anion into LDH gallery after intercalation. The anomalous low frequency dispersion (ALFD) has been used to describe the dielectric response of Zn–Cd–Al–LDH–DS nanostructure using the second type of universal power law. At low frequency, the polarization effect of electrodes caused the rising in dielectric constant and loss values. An important result of the dielectric measurements is the calculated dc conductivity values, which are new in dielectric spectroscopy of LDH materials. An important result of the electron spin resonance (ESR) spectra exhibited the successful intercalation of DS molecule into LDH gallery. The g-factor value was affected by

Biodegradation of the anionic surfactant sodium dodecyl sulfate by local bacterial isolate

International Nuclear Information System (INIS)

Ibrahim, H.M.M.; NoorEl-Din, M.R.

2011-01-01

Anionic surfactants, e.g., sodium dodecyl sulfate (SDS), as a main components in the detergent and cosmetic industries, contribute significantly to the pollution profile of sewage and wastewaters of all kinds. The purpose of this study was to isolate local SDS degrading bacteria. Screening was carried out by the conventional enrichment culture technique. One bacterial isolate was obtained; this isolate was primarily defined as gram-negative rods . It was capable of degrading 100% of 1000 and 2000 mg/l of SDS after 6 days of incubation. The isolate exhibited maximum growth at SDS concentration 4000 mg/I, but it was significantly decreased at higher concentration (16000 mg/I).All the carbon sources being tested repressed the degradation ability. Sodium nitrate at concentration of 2.0 g/I was the best nitrogen source for growth and SDS biodegradation, it enhanced the degradation of 3000 mg/I SDS by 95%,i.e., by 32% upon the control (broth medium containing NH 4 Cl). SDS degradation by the bacterium was optimum at initial ph 8.5, incubation temperature 35 degree C, and inoculum size 2% (v/v). Under the optimized conditions, almost 98% of initial SDS concentration (4000 mg/l) was degraded after 120 h of incubation. Gamma irradiation did not improve the biodegradation ability of this bacterial isolate.

Sodium Dodecyl Sulfate (SDS-Loaded Nanoporous Polymer as Anti-Biofilm Surface Coating Material

Directory of Open Access Journals (Sweden)

Sokol Ndoni

2013-02-01

Full Text Available Biofilms cause extensive damage to industrial settings. Thus, it is important to improve the existing techniques and develop new strategies to prevent bacterial biofilm formation. In the present study, we have prepared nanoporous polymer films from a self-assembled 1,2-polybutadiene-b-polydimethylsiloxane (1,2-PB-b-PDMS block copolymer via chemical cross-linking of the 1,2-PB block followed by quantitative removal of the PDMS block. Sodium dodecyl sulfate (SDS was loaded into the nanoporous 1,2-PB from aqueous solution. The SDS-loaded nanoporous polymer films were shown to block bacterial attachment in short-term (3 h and significantly reduce biofilm formation in long-term (1 week by gram-negative bacterium Escherichia coli. Tuning the thickness or surface morphology of the nanoporous polymer films allowed to extent the anti-biofilm capability.

An investigation of chitosan and sodium dodecyl sulfate interactions in acetic media

Directory of Open Access Journals (Sweden)

Petrović Lidija B.

2016-01-01

Full Text Available Polymer/surfactant association is a cooperative phenomenon where surfactant binds to the polymer in the form of aggregates, usually through electrostatic or hydrophobic forces. As already known, polyelectrolytes may interact with oppositely charged surfactants through electrostatic attraction that results in polymer/surfactant complex formation. This behavior could be desirable in wide range of application of polymer/surfactant mixtures, such as improving colloid stability, gelling, emulsification and microencapsulation. In the present study surface tension, turbidity, viscosity and electrophoretic mobility measurements were used to investigate interactions of cationic polyelectrolyte chitosan (Ch and oppositely charged anionic surfactant, sodium dodecyl sulfate (SDS, in buffered water. Obtained results show the presence of interactions that lead to Ch/SDS complexes formation at all investigated pH and for all investigated polymer concentrations. Mechanisms of interaction, as well as characteristics of formed Ch/SDS complexes, are highly dependent on their mass ratio in the mixtures, while pH has no significant influence. [Projekat Ministarstva nauke Republike Srbije, br. II46010

Phosphorylation of acidic ribosomal proteins from rabbit reticulocytes by a ribosome-associated casein kinase

DEFF Research Database (Denmark)

Issinger, O G

1977-01-01

Two acidic proteins from 80-S ribosomes were isolated and purified to homogeneity. The purified acidic proteins could be phosphorylated by casein kinase using [gamma-32P]ATP and [gamma-32P]GTP as a phosphoryl donor. The proteins became phosphorylated in situ, too. Sodium dodecyl sulfate polyacryl......Two acidic proteins from 80-S ribosomes were isolated and purified to homogeneity. The purified acidic proteins could be phosphorylated by casein kinase using [gamma-32P]ATP and [gamma-32P]GTP as a phosphoryl donor. The proteins became phosphorylated in situ, too. Sodium dodecyl sulfate...

Influence of sodium dodecyl sulfate on the reaction between Nile Blue A and hydrogen peroxide

Directory of Open Access Journals (Sweden)

IVANA A. JANKOVIC

1999-05-01

Full Text Available The influence of the anionic surfactant sodium dodecyl sulfate on the rate of the reaction between the cationic form of Nile Blue A and hydrogen peroxide was investigated in the pH range from 5 to 8.5. A retardation of the oxidation of Nile Blue A with hydrogen peroxide of three orders of magnitude was observed at pH 8.5 in the presence of anionic micelles compared to the kinetic data in water. The retardation effect was less pronounced at lower pH values. These effects were explained by the electrostatic interaction of the species involved in the reaction with the negatively charged micellar surface and their effective separation in the vicinity of the micellar surface.

Transport Modeling of Modified Magnetite Nanoparticles with Sodium Dodecyl Sulfate in a Saturated Sandy Soil

Directory of Open Access Journals (Sweden)

Ahmad Farrokhian Firouzi

2017-02-01

Full Text Available Introduction: Nanoparticles due to their large specific area and reactivity recently have been used in several environmental remediation applications such as degradation of organic compounds and pesticides and adsorption of heavy metals and inorganic anions. Because of concern over potential threats of nanoparticle releases into the soil–water environment, a number of studies have been carried out to investigate the transport, retention and deposition of nanoparticles in saturated porous media. Many of these studies are based on measurements of transport in columns packed with idealized porous media consisting of spherical glass beads or sand. The nanoparticles are usually introduced into the column and breakthrough curve concentrations are measured at the column outlet. To examine the effect of various parameters on the transport of nanoparticles in porous medium, for convenience, all the parameters considered the same in the experiments, and only one parameter in the experiments is changed and investigated. Materials and Methods: The objective of this research is quantitative study of modified magnetite nanoparticles transport in saturated sand-repacked columns. The modified magnetite nanoparticles with Sodium dodecyl sulfate were synthesized following the protocol described by Si et al. (2004. The experimental setup included a suspension reservoir, Teflon tubing, a HPLC pump, and a glass column (2.5 cm i.d. and 20 cm height. Therefore, breakthrough curves of modified magnetite nanoparticles with Sodium dodecyl sulfate and chloride were determined under saturated conditions and influence of nanoparticles concentration (0.1 and 0.5 g.L-1 and pore velocity (pressure head of 2 and 10 cm on nanoparticles transport were investigated. For each medium bed, the background solution were first pumped through the column in the up-flow mode to obtain a steady flow state. Then, a tracer test was conducted by introducing CaCl2 solution into the column

Efficient extraction of proteins from recalcitrant plant tissue for subsequent analysis by two-dimensional gel electrophoresis.

Science.gov (United States)

Parkhey, Suruchi; Chandrakar, Vibhuti; Naithani, S C; Keshavkant, S

2015-10-01

Protein extraction for two-dimensional electrophoresis from tissues of recalcitrant species is quite problematic and challenging due to the low protein content and high abundance of contaminants. Proteomics in Shorea robusta is scarcely conducted due to the lack of a suitable protein preparation procedure. To establish an effective protein extraction protocol suitable for two-dimensional electrophoresis in Shorea robusta, four procedures (borate buffer/trichloroacetic acid extraction, organic solvent/trichloroacetic acid precipitation, sucrose/Tris/phenol, and organic solvent/phenol/sodium dodecyl sulfate) were evaluated. Following these, proteins were isolated from mature leaves and were analyzed for proteomics, and also for potential contaminants, widely reported to hinder proteomics. The borate buffer/trichloroacetic acid extraction had the lowest protein yield and did not result in any banding even in one-dimensional electrophoresis. In contrast, organic solvent/phenol/sodium dodecyl sulfate extraction allowed the highest protein yield. Moreover, during proteomics, organic solvent/phenol/sodium dodecyl sulfate extracted protein resolved the maximum number (144) of spots. Further, when proteins were evaluated for contaminants, significant (77-95%) reductions in the nucleic acids, phenol, and sugars were discernible with refinement in extraction procedure. Accumulated data suggested that the organic solvent/phenol/sodium dodecyl sulfate extraction was the most effective protocol for protein isolation for proteomics of Shorea robusta and can be used for plants that have a similar set of contaminants. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The structure of the antimicrobial active center of lactoferricin B bound to sodium dodecyl sulfate micelles.

Science.gov (United States)

Schibli, D J; Hwang, P M; Vogel, H J

1999-03-12

Lactoferricin B (LfcinB) is a 25-residue antimicrobial peptide released from bovine lactoferrin upon pepsin digestion. The antimicrobial center of LfcinB consists of six residues (RRWQWR-NH2), and it possesses similar bactericidal activity to LfcinB. The structure of the six-residue peptide bound to sodium dodecyl sulfate (SDS) micelles has been determined by NMR spectroscopy and molecular dynamics refinement. The peptide adopts a well defined amphipathic structure when bound to SDS micelles with the Trp sidechains separated from the Arg residues. Additional evidence demonstrates that the peptide is oriented in the micelle such that the Trp residues are more deeply buried in the micelle than the Arg and Gln residues.

Evaluation of toxicity reduction of sodium dodecyl sulfate submitted to electron beam radiation

Science.gov (United States)

Romanelli, M. F.; Moraes, M. C. F.; Villavicencio, A. L. C. H.; Borrely, S. I.

2004-09-01

Surfactants, as detergent active substances, are an important source of pollution causing biological adverse effects to aquatic organisms. Several data have been showing ecological disturbance due to the high concentration of surfactants on receiving waters and on wastewater treatment plants. Ionizing radiation has been proved as an effective technology to decompose organic substances and few papers have included ecotoxicological aspects. This paper shows the reduction of acute toxicity of a specific surfactant, sodium dodecyl sulfate (SDS), when diluted in distilled water and submitted to electron beam radiation. The study included two test-organisms, the marine bacteria Vibrio fischeri and the crustacean Daphnia similis. Radiation processing resulted in an important acute toxicity removal for both assays, which can be summarized between 70% and 96%, using 3.0, 6.0, 9.0 and 12.0 kGy as radiation doses. Nevertheless, lower doses demonstrated better effect than 9.0 and 12.0 kGy and the bacterium assay was more sensitive to SDS than crustacean assay.

The removal of Tartrazine dye by modified Alumina with sodium dodecyl sulfate from aqueous solutions: equilibrium and thermodynamic studies

Directory of Open Access Journals (Sweden)

A. Parchebaf Jadid

2017-11-01

Full Text Available Edible colors are materials which in the case of adding to food and drinks cause transferring color to them. Most of these colors are not acceptable in terms of applying in human food and underlies various diseases like gastrointestinal disorders, renal, liver and blood toxicity. The goal of this study was investigating the efficiency of improved alumina by sodium dodecyl sulfate (SDS in eliminating Tartrazine from aqueous environments. In this research, the impact of effective parameters such as initial concentration of Tartrazine, time, pH, alumina dose and SDS value were studied in order to approach an optimal condition for eliminating the color. Also, absorption behavior was evaluated by Freundlich and Langmuir isotherms. The highest efficiency of Tartrazine elimination in the solution resulted in optimal pH of 2, the amount of adsorbent 1.5 g/L, 16 min duration and value 0.04 SDS g/l which was obtained for dye concentration 5 mg/L about 94.13%. Also, results suggested that Tartrazine absorption follows Langmuir isotherm (R2 = 0.9867. Obtained results from thermodynamic studies such as Gibbs free energy (-5.728 Kj/mol and enthalpy (-85.86 Kj/mol and entropy (-271.102 J/mol.K also suggested that the absorption process was exothermic. The results of this research suggested that improved alumina by sodium dodecyl sulfate had a relative good capability in Tartrazine elimination from aqueous environments. Thus

Fluorescence enhancement effect for the determination of curcumin with yttrium(III)-curcumin-sodium dodecyl benzene sulfonate system

International Nuclear Information System (INIS)

Wang Feng; Huang Wei; Wang Yanwei

2008-01-01

It is found that the fluorescence of curcumin is greatly enhanced by yttrium(III) (Y 3+ ) in the presence of sodium dodecyl benzene sulfonate. Based on this, a sensitive fluorimetric method for the determination of curcumin in aqueous solution is proposed. In the potassium hydrogen phthalate (KHP) buffer, the fluorescence intensity of curcumin is proportional to the concentration of curcumin in the range of 7.37x10 -4 -0.18, 0.18-2.95 μg mL -1 and the detection limit is 0.1583 ng mL -1 . The actual samples are satisfactorily determined. In addition, the interaction mechanism is also studied

Structural analysis of protein complexes with sodium alkyl sulfates by small-angle scattering and polyacrylamide gel electrophoresis.

Science.gov (United States)

Ospinal-Jiménez, Mónica; Pozzo, Danilo C

2011-02-01

Small-angle X-ray (SAXS) and neutron (SANS) scattering is used to probe the structure of protein-surfactant complexes in solution and to correlate this information with their performance in gel electrophoresis. Proteins with sizes between 6.5 to 116 kDa are denatured with sodium alkyl sulfates (SC(x)S) of variable tail lengths. Several combinations of proteins and surfactants are analyzed to measure micelle radii, the distance between micelles, the extension of the complex, the radius of gyration, and the electrophoretic mobility. The structural characterization shows that most protein-surfactant complexes can be accurately described as pearl-necklace structures with spherical micelles. However, protein complexes with short surfactants (SC(8)S) bind with micelles that deviate significantly from spherical shape. Sodium decyl (SC(10)S) and dodecyl (SC(12)S, more commonly abbreviated as SDS) sulfates result in the best protein separations in standard gel electrophoresis. Particularly, SC(10)S shows higher resolutions for complexes of low molecular weight. The systematic characterization of alkyl sulfate surfactants demonstrates that changes in the chain architecture can significantly affect electrophoretic migration so that protein-surfactant structures could be optimized for high resolution protein separations.

Determination of albumins by its quenching effect on the fluorescence of Tb{sup 3+}-oxolinic acid complex in presence of sodium dodecyl sulphate

Energy Technology Data Exchange (ETDEWEB)

Wu Xia [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zheng Jinhua [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Guo Changying [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Yang Jinghe [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)]. E-mail: yjh@sdu.edu.cn; Ding Honghong [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Hu Zhiyong [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Li Chao [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

2007-09-15

It is found that the fluorescence intensity of Tb{sup 3+}-oxolinic acid (OA) complex can be greatly quenched by albumins in sodium dodecyl sulphate (SLS). Under optimum conditions, the quenched fluorescence intensity is in proportion to the concentration of proteins in the range of 5.0x10{sup -8}-1.0x10{sup -5} g ml{sup -1} for bovine serum albumin (BSA), 1.0x10{sup -7}-1.0x10{sup -5} g ml{sup -1} for human serum albumin (HSA) and 4.0x10{sup -7}-1.0x10{sup -5} g ml{sup -1} for egg albumin (EA). Their detection limits (S/N=3) are 2.1x10{sup -8}, 2.5x10{sup -8} and 5.0x10{sup -8} g ml{sup -1}, respectively. In addition, the interaction mechanism is also investigated.

Characterization of sodium dodecyl sulfate-resistant proteolytic activity in the hyperthermophilic archaebacterium Pyrococcus furiosus

Energy Technology Data Exchange (ETDEWEB)

Blumentals, I.I.; Robinson, A.S.; Kelly, R.M. (Johns Hopkins Univ., Baltimore, MD (USA))

1990-07-01

Cell extracts from Pyrococcus furiosus were found to contain five proteases, two of which (S66 and S102) are resistant to sodium dodecyl sulfate (SDS) denaturation. Cell extracts incubated at 98{degree}C in the presence of 1% SDS for 24 h exhibited substantial cellular proteolysis such that only four proteins could be visualized by amido black-Coomassie brilliant blue staining of SDS-polyacrylamide gels. The SDS-treated extract retained 19% of the initial proteolytic activity as represented by two proteases, S66 (66 kilodaltons (kDa)) and S102 (102 kDa). Immunoblot analysis with guinea pig sera containing antibodies against protease S66 indicated that S66 is related neither to S102 nor to the other proteases. The results of this analysis also suggest that S66 might be the hydrolysis product of a 200-kDa precursor which does not have proteolytic activity. The 24-h SDS-treated extract showed unusually thermostable proteolytic activity; the measured half-life at 98{degree}C was found to be 33 h. Proteases S66 and S102 were also resistant to denaturation by 8 M urea, 80 mM dithiothreitol, and 5% {beta}-mercaptoethanol. Purified protease S66 was inhibited by phenylmethylsulfonyl fluoride and diisopropyl fluorophosphate but not by EDTA, ethylene glycol-bis({beta}-aminoethyl ether)-N,N,N{prime},N{prime}-tetraacetic acid, or iodoacetic acid. These results indicate that S66 is a serine protease. Amino acid ester hydrolysis studies showed that protease S66 was hydrolytically active towards N-benzoyl-L-arginine ethyl ester.

Measuring the enthalpies of interaction between glycine, L-cysteine, glycylglycine, and sodium dodecyl sulfate in aqueous solutions

Science.gov (United States)

Badelin, V. G.; Mezhevoi, I. N.; Tyunina, E. Yu.

2017-03-01

Calorimetric measurements of enthalpies of solution Δsol H m for glycine, L-cysteine, and glycylglycine in aqueous solutions of sodium dodecyl sulfate (SDS) with concentrations of up to 0.05 mol kg-1 are made. Standard enthalpy of solution Δsol H 0 and enthalpy of transfer Δtr H 0 of the dipeptide from water into mixed solvent are calculated. The calculated enthalpy coefficients of paired interactions of amino acids and dipeptide with SDS prove to be positive. Hydrophobic interactions between the biomolecules and SDS are found to have a major impact on the enthalpies of interaction in the three-component systems under study, within the indicated range of concentrations.

Effects of various polyoxyethylene sorbitan monooils (Tweens) and sodium dodecyl sulfate on reflux synthesis of copper nanoparticles

International Nuclear Information System (INIS)

Zhang Xifeng; Yin Hengbo; Cheng Xiaonong; Hu Huifeng; Yu Qi; Wang Aili

2006-01-01

Size-controlled synthesis of phase pure Cu nanoparticles was carried out by using copper sulfate pentahydrate as a precursor, ascorbic acid as a reductant, Tweens and sodium dodecyl sulfate (SDS) as modifiers in an aqueous solution at 80 deg. C. The as-prepared Cu nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and Fourier transform infrared (FT-IR). The stabilizing effects of SDS and Tweens on the Cu nanoparticles should be through the coordination between Cu nanoparticles and the respective sulfate group and oxygen-containing bond. The synergic effect of the composite SDS and Tweens on Cu nanoparticles was different from those arising from the individuals

Voltammetric Determination of Ivabradine Hydrochloride Using Multiwalled Carbon Nanotubes Modified Electrode in Presence of Sodium Dodecyl Sulfate.

Science.gov (United States)

Attia, Ali Kamal; Abo-Talib, Nisreen Farouk; Tammam, Marwa Hosny

2017-04-01

Purpose: A new sensitive sensor was fabricated for the determination of ivabradine hydrochloride (IH) based on modification with multiwalled carbon nanotubes using sodium dodecyl sulfate as micellar medium to increase the sensitivity. Methods: The electrochemical behavior of IH was studied in Britton-Robinson buffer (pH: 2.0-11.0) using cyclic and differential pulse voltammetry. Results: The voltammetric response was linear over the range of 3.984 x 10 -6 -3.475 x 10 -5 mol L -1 . The limits of detection and quantification were found to be 5.160 x 10 -7 and 1.720 x 10-6 mol L -1 , respectively. Conclusion: This method is suitable for determination of IH in tablets and plasma.

The corrosion properties of phosphate coating on AZ31 magnesium alloy: The effect of sodium dodecyl sulfate (SDS) as an eco-friendly accelerating agent

Energy Technology Data Exchange (ETDEWEB)

Amini, R. [Department of Polymer Engineering and Color Technology, AmirKabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sarabi, A.A., E-mail: sarabi@aut.ac.ir [Department of Polymer Engineering and Color Technology, AmirKabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2011-06-01

Sodium nitrite has been used as an accelerating agent in phosphating bath to improve its properties. However, it is well known that sodium nitrite is a carcinogenic component in phosphating sludge. In this study, it has been aimed to replace sodium nitrite by an environmentally friendly accelerating agent. To this end, sodium dodecyl sulfate (SDS) was used in phosphating bath to improve the phosphate coating formation on an AZ31 magnesium alloy. The effect of SDS/sodium nitrite ratio on the phosphated samples properties was also studied. Using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), direct current (DC) polarization and electrochemical impedance spectroscopy (EIS) the properties of phosphated magnesium samples were studied. Results showed uniform phosphate coating formation on the magnesium sample mostly in hopeite phase composition. In addition, a denser and less permeable coating can be obtained at these conditions. The corrosion resistance of the phosphated samples was superiorly improved using higher SDS concentration in the phosphating bath.

The corrosion properties of phosphate coating on AZ31 magnesium alloy: The effect of sodium dodecyl sulfate (SDS) as an eco-friendly accelerating agent

International Nuclear Information System (INIS)

Amini, R.; Sarabi, A.A.

2011-01-01

Sodium nitrite has been used as an accelerating agent in phosphating bath to improve its properties. However, it is well known that sodium nitrite is a carcinogenic component in phosphating sludge. In this study, it has been aimed to replace sodium nitrite by an environmentally friendly accelerating agent. To this end, sodium dodecyl sulfate (SDS) was used in phosphating bath to improve the phosphate coating formation on an AZ31 magnesium alloy. The effect of SDS/sodium nitrite ratio on the phosphated samples properties was also studied. Using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), direct current (DC) polarization and electrochemical impedance spectroscopy (EIS) the properties of phosphated magnesium samples were studied. Results showed uniform phosphate coating formation on the magnesium sample mostly in hopeite phase composition. In addition, a denser and less permeable coating can be obtained at these conditions. The corrosion resistance of the phosphated samples was superiorly improved using higher SDS concentration in the phosphating bath.

Polyelectrolyte-surfactant complexes formed by poly[3,5-bis(trimethylammoniummethyl)4-hydroxystyrene iodide]-block-poly(ethylene oxide) and sodium dodecyl sulfate in aqueous solutions

Czech Academy of Sciences Publication Activity Database

Štěpánek, M.; Matějíček, P.; Procházka, K.; Filippov, Sergey K.; Angelov, Borislav; Šlouf, Miroslav; Mountrichas, G.; Pispas, S.

2011-01-01

Roč. 27, č. 9 (2011), s. 5275-5281 ISSN 0743-7463 R&D Projects: GA MŠk ME09059; GA ČR GCP205/11/J043; GA ČR GAP208/10/0353 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyelectrolyte-surfactant complexes * sodium dodecyl sulfate * small-angle X-ray scattering Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.186, year: 2011

Voltammetric Determination of Ivabradine Hydrochloride Using Multiwalled Carbon Nanotubes Modified Electrode in Presence of Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Ali Kamal Attia

2017-04-01

Full Text Available Purpose: A new sensitive sensor was fabricated for the determination of ivabradine hydrochloride (IH based on modification with multiwalled carbon nanotubes using sodium dodecyl sulfate as micellar medium to increase the sensitivity. Methods: The electrochemical behavior of IH was studied in Britton-Robinson buffer (pH: 2.0-11.0 using cyclic and differential pulse voltammetry. Results: The voltammetric response was linear over the range of 3.984 x 10-6-3.475 x 10-5 mol L-1. The limits of detection and quantification were found to be 5.160 x 10-7 and 1.720 x 10-6 mol L-1, respectively. Conclusion: This method is suitable for determination of IH in tablets and plasma.

Development of a sodium dodecyl sulfate-polyacrylamide gel electrophoresis reference method for the analysis and identification of fish species in raw and heat-processed samples : A collaborative study

DEFF Research Database (Denmark)

Pineiro, C.; Barros-Velazquez, J.; Perez-Martin, R.I.

1999-01-01

A collaborative study was carried out in seven European labs with the aim of achieving a sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) standard operation procedure to identify fish species in raw and cooked samples. Urea and SDS-containing solutions were evaluated...... silver stained, yielded good results and afforded higher reproducibility, thus allowing a better matching of results among the laboratories participating in this collaborative study. Under the optimized technical conditions described above, all the fish species tested, either raw and cooked, yielded...... seemed not to be influenced so much by the state of the sample (raw, cooked at 60 degrees C, cooked at 85 degrees C). Desalting, ultrafiltration or treatment with RNase/DNase did not improve the discriminatory power of the protein patterns. Commercial homogeneous 15% ExcelGels, especially when they were...

Thermo-acoustical analysis of sodium dodecyl sulfate: Fluconazole (antifungal drug) based micellar system in hydro-ethanol solutions for potential drug topical application

International Nuclear Information System (INIS)

Bhardwaj, Tarun; Bhardwaj, Varun; Sharma, Kundan; Gupta, Abhishek; Cameotra, Swaranjit Singh; Sharma, Poonam

2014-01-01

Highlights: • The mixed micellar system was analyzed for sodium dodecyl sulfate and fluconazole. • Early micellization was found with CMC shift towards lower surfactant concentration. • Negative ΔG m o values suggested that the micelle formation is spontaneous and feasible. • Thermo-acoustical parameters revealed the existence of intermolecular interactions within the molecules. - Abstract: Micellar systems hold excellent drug delivery applications due to their capability to solubilize a large number of hydrophobic and hydrophilic molecules. In this present work, the mixed micelle formation between the anionic surfactant sodium dodecyl sulfate (SDS) and the ‘Azole’ derivative antifungal drug fluconazole (FLZ) have been studied at four temperatures in different hydro-ethanolic solutions. The critical micelle concentration (CMC) was determined by specific conductance techniques and the experimental data was used to calculate several useful thermodynamic parameters, like standard free energy, enthalpy and entropy of micelle formation. Early micellization was found with critical micelle concentration shifting towards lower concentration (CMC) than the standard concentration of SDS in water at 25 °C suggesting that drug and the solvent system facilitates the micellization process. In addition, the transport properties were examined by employing controlled approaches likely, apparent molar volume (ϕ v ), apparent molar adiabatic compression (ϕ k ), and isentropic compression (κ s ) of SDS in presence of FLZ. These parameters revealed the existence of intermolecular interactions within the molecules. Therefore, this study would cast light on utilizing surfactant immobilized FLZ system for better topical biological action

Inactivation of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 on tomatoes using sodium dodecyl sulphate, levulinic acid and sodium hypochlorite solution

Directory of Open Access Journals (Sweden)

Oluwatosin Ademola Ijabadeniyi

2017-04-01

Full Text Available The effectiveness of sodium dodecyl sulphate (SDS, sodium hypochlorite solution and levulinic acid in reducing the survival of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 was evaluated. The results against heat adapted L. monocytognes revealed that sodium hypochlorite solution was the least effective, achieving log reduction of 2.75, 2.94 and 3.97 log colony forming unit (CFU/mL for 1, 3 and 5 minutes, respectively. SDS was able to achieve 8 log reduction for both heat adapted and chlorine adapted bacteria. When used against chlorine adapted L. monocytogenes sodium hypochlorite solution achieved log reduction of 2.76, 2.93 and 3.65 log CFU/mL for 1, 3 and 5 minutes, respectively. Using levulinic acid on heat adapted bacteria achieved log reduction of 3.07, 2.78 and 4.97 log CFU/mL for 1, 3, 5 minutes, respectively. On chlorine adapted bacteria levulinic acid achieved log reduction of 2.77, 3.07 and 5.21 log CFU/mL for 1, 3 and 5 minutes, respectively. Using a mixture of 0.05% SDS and 0.5% levulinic acid on heat adapted bacteria achieved log reduction of 3.13, 3.32 and 4.79 log CFU/mL for 1, 3 and 5 minutes while on chlorine adapted bacteria it achieved 3.20, 3.33 and 5.66 log CFU/mL, respectively. Increasing contact time also increased log reduction for both test pathogens. A storage period of up to 72 hours resulted in progressive log reduction for both test pathogens. Results also revealed that there was a significant difference (P≤0.05 among contact times, storage times and sanitizers. Findings from this study can be used to select suitable sanitizers and contact times for heat and chlorine adapted L. monocytogenes in the fresh produce industry.

The effect of chloramphenicol on synthesis of ΦX 174-specific proteins and detection of the cistron A protein

NARCIS (Netherlands)

Mei, D. Van Der; Zandberg, J.; Jansz, H.S.

1972-01-01

Synthesis of ΦX 174-specific proteins in Escherichia coli H 502 was examined on sodium dodecyl sulphate-acrylamide gels by coelectrophoresis of proteins from [3H]leucine-labelled infected cells and [14C]leucine-labelled reference cells, which had been infected with ultraviolet-light irradiated

Changes in the protein profile of Habanero pepper ( Capsicum ...

African Journals Online (AJOL)

Protein profile was studied during the development of Capsicum chinense somatic embryos. The total protein content and profile of polypeptides (by sodium dodecyl sulfate polyacrylamide gel electrophoresis) of somatic embryos at different developmental stages (globular, heart-shaped, torpedo and cotyledonary stages) ...

Antigenic profile of heat-killed versus thimerosal-treated Leishmania major using sodium dodecyl sulfate-polyacrylamide gel electrophoresis

Directory of Open Access Journals (Sweden)

Reza Arjmand

2015-01-01

Full Text Available Background: Leishmania is a parasitic protozoan of trypanosomatidae family which causes a wide spectrum of diseases ranging from self-healing cutaneous lesions to deadly visceral forms. In endemic areas, field trials of different preparations of Leishmania total antigen were tested as leishmaniasis vaccine. Two preparations of killed Leishmania major were produced In Iran, which were heat-killed vaccine called autoclaved L. major (ALM and thimerosal-treated freeze-thawed vaccine called killed L. major (KLM. In this study, the protein content of both ALM and KLM were compared with that of freshly harvested intact L. major promastigotes using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. Materials and Methods: L. major (MRHO/IR/75/ER from pre-infected Balb/c mice was isolated with modified Novy-MacNeal-Nicolle (NNN medium and then subcultured in liquid RPMI 1640 medium supplemented with fetal calf serum (FCS 20% for mass production. Two preparations of KLM and ALM were produced by Razi Vaccine and Serum Research Institute, Iran, under WHO/TDR supervision. Electrophoresis was performed by SDS-PAGE method and the gel was stained by Coomassie brilliant blue dye. The resultant unit bands were compared using standard molecular proteins. Results: Electrophoresis of the two preparations produced many bands from 10 kDa to 100 kDa. KLM bands were much like those of freshly harvested intact L. major. Conclusion: It is concluded that although there are similar bands in the three forms of Leishmania antigens, there are some variations which might be considered for identification and purification of protective immunogens in a total crude antigen, and detection of their stability is essential for the production and marketing of a putative vaccine.

Photochemistry of aromatic ketones in sodium dodecyl sulphate micelles in the presence of unsaturated fatty acids

Directory of Open Access Journals (Sweden)

DEJAN Z. MARKOVIC

2004-02-01

Full Text Available Laser-flash photolysis has been employed to characterize the behaviour of the free radicals created in the photochemical reaction of benzophenone (BZP, as well as of its lipoidal derivative, benzophenone-4-heptyl-4’-pentanoic acid (BHPA, with chosen unsaturated fatty acids in sodium dodecyl sulphate micelles. The calculated rate constants were used to study the “cage effect”, i.e., the recombination of the created radical-pairs (BZP, BHPA ketyl radical - lipid radical inside the highly limited space of the SDS micelles. The “cage effect” appears to be the dominant event inside SDS micelles, dependent on the structure of both the reactants-precursors. The fractions of the initially created radical-pairs which escape the “cage effect” and exit into the surrounding aqueous phase do not exceed 16 %. This fact is of enormous importance for the self-control of the pathogenic process of lipid peroxidation.

Application and Mechanism of Anionic Collector Sodium Dodecyl Sulfate (SDS in Phosphate Beneficiation

Directory of Open Access Journals (Sweden)

Kun Sun

2017-02-01

Full Text Available Phosphate ore is a valuable strategic resource. Most phosphate ore in China is collophane. Utilization of mid-low grade collophane is necessary to maintain social sustainable development. The gravity-flotation combination separation process can be utilized to separate mid-low grade collophane, but the process consumes a large quantity of acid in the reverse stage. Sodium dodecyl sulfate (SDS was used as a dolomite collector in this study to reduce the acid consumption of collophane flotation. SDS effectively removed dolomite from the gravity concentrate when no other reagents were present. Flotation test results showed that, compared to the conventional gravity-flotation process, the proposed SDS-based process reduced phosphoric acid dosage from 6.1 kg/t to 3.9 kg/t with similar separation results. The SDS action mechanisms on dolomite were further investigated by zeta potential analysis, single mineral flotation tests, infrared spectrum detection, and theoretical analysis. The results indicate that the SDS adsorption on dolomite is mainly physical adsorption, and that favorable separation effects between collophane and dolomite may be attributed to physical adsorption and entrainment. In addition, it also indicates that the physical adsorption can be utilized to remove dolomite from phosphate on account of zeta potential differences when the separate feed is coarse.

Enhanced removal of detergent and recovery of enzymatic activity following sodium dodecyl sulfate-polyacrylamide gel electrophoresis: UUse of casein in gel wash buffer

International Nuclear Information System (INIS)

McGrew, B.R.; Green, D.M.

1990-01-01

The inclusion of 1% casein or bovine serum albumin in buffer used to reactivate enzymes subjected to sodium dodecyl sulfate (SDS)-polyacrylamide electrophoresis resulted in accelerated removal of SDS and restoration of nuclease and beta-galactosidase enzyme activities. Nuclease and beta-galactosidase activities which are absent from gels after longer wash procedures are detectable with this technique. Enzyme activity in gels prepared with SDS which contained inhibitory contaminants was partially restored by the casein wash procedure. The threshold of detection of two-dimensionally separated deoxyribonuclease I using the casein wash procedure was 1 picogram

Dispersive admicelle solid-phase extraction based on sodium dodecyl sulfate coated Fe3 O4 nanoparticles for the selective adsorption of three alkaloids in Gegen-Qinlian oral liquid before high-performance liquid chromatography.

Science.gov (United States)

Shi, Zhihong; Xu, Dan; Zhao, Xuan; Li, Xinghong; Shen, Huimin; Yang, Bing; Zhang, Hongyi

2017-12-01

A novel dispersive admicelle solid-phase extraction method based on sodium dodecyl sulfate-coated Fe 3 O 4 nanoparticles was developed for the selective adsorption of berberine, coptisine, and palmatine in Gegen-Qinlian oral liquid before high-performance liquid chromatography. Fe 3 O 4 nanoparticles were synthesized by a chemical coprecipitation method and characterized by using transmission electron microscopy. Under acidic conditions, the surface of Fe 3 O 4 nanoparticles was coated with sodium dodecyl sulfate to form a nano-sized admicelle magnetic sorbent. Owing to electrostatic interaction, the alkaloids were adsorbed onto the oppositely charged admicelle magnetic nanoparticles. The quick separation of the analyte-adsorbed nanoparticles from the sample solution was performed by using Nd-Fe-B magnet. Best extraction efficiency was achieved under the following conditions: 800 μL Fe 3 O 4 nanoparticles suspension (20 mg/mL), 150 μL sodium dodecyl sulfate solution (10 mg/mL), pH 2, and vortexing time 2 min for the extraction of alkaloids from 10 mL of diluted sample. Four hundred microliters of methanol was used to desorb the alkaloids by vortexing for 1 min. Satisfactory extraction recoveries were obtained in the range of 85.9-120.3%, relative standard deviations for intra- and interday precisions were less than 6.3 and 10.0%, respectively. Finally, the established method was successfully applied to analyze the alkaloids in two batches of Gegen-Qinlian oral liquids. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sustained release of simvastatin from hollow carbonated hydroxyapatite microspheres prepared by aspartic acid and sodium dodecyl sulfate.

Science.gov (United States)

Wang, Ke; Wang, Yinjing; Zhao, Xu; Li, Yi; Yang, Tao; Zhang, Xue; Wu, Xiaoguang

2017-06-01

Hollow carbonated hydroxyapatite (HCHAp) microspheres as simvastatin (SV) sustained-release vehicles were fabricated through a novel and simple one-step biomimetic strategy. Firstly, hollow CaCO 3 microspheres were precipitated through the reaction of CaCl 2 with Na 2 CO 3 in the presence of aspartic acid and sodium dodecyl sulfate. Then, the as-prepared hollow CaCO 3 microspheres were transformed into HCHAp microspheres with a controlled anion-exchange method. The HCHAp microspheres were 3-5μm with a shell thickness of 0.5-1μm and were constructed of short needle nanoparticles. The HCHAp microspheres were then loaded with SV, exhibiting excellent drug-loading capacity and sustained release properties. These results present a new material synthesis strategy for HCHAp microspheres and suggest that the as-prepared HCHAp microspheres are promising for applications in drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

A nano-bio interfacial protein corona on silica nanoparticle.

Science.gov (United States)

Zhang, Hongyan; Peng, Jiaxi; Li, Xin; Liu, Shengju; Hu, Zhengyan; Xu, Guiju; Wu, Ren'an

2018-07-01

Nano-bio interaction takes the crucial role in bio-application of nanoparticles. The systematic mapping of interfacial proteins remains the big challenge as low level of proteins within interface regions and lack of appropriate technology. Here, a facile proteomic strategy was developed to characterize the interfacial protein corona (noted as IPC) that has strong interactions with silica nanoparticle, via the combination of the vigorous elution with high concentration sodium dodecyl sulfate (SDS) and the pre-isolation of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The trace level IPCs for silica nanoparticle were thus qualitatively and quantitatively identified. Bioinformatics analyses revealed the intrinsic compositions, relevance and potential regularity addressing the strong interactions between IPC and nanoparticle. This strategy in determining IPCs is opening an avenue to give a deep insight to understand the interaction between proteins and not only nanoparticles but also other bulk materials. Copyright © 2018 Elsevier B.V. All rights reserved.

Thermodynamic selectivity of functional agents on zeolite for sodium dodecyl sulfate sequestration

Energy Technology Data Exchange (ETDEWEB)

Leng, Ling; Wang, Jian [Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China); Qiu, Xianxiu; Zhao, Yanxiang; Yip, Yuk-Wang; Law, Ga-Lai [Department of Applied Biology and Chemical Technology, State Key Laboratory of Chirosciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China); Shih, Kaimin; Zhou, Zhengyuan [Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Hong Kong SAR (China); Lee, Po-Heng, E-mail: poheng76@gmail.com [Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China)

2016-11-15

Highlights: • A thermodynamic approach to select a functional agent for adsorbent is proposed. • ITC and QCS were used to interpret the interaction between adsorbate and agent. • The interaction identifies the adsorption mechanism and performance. • This approach enables the manipulation of adsorption capacity optimization. - Abstract: This study proposes a thermodynamic approach to effectively select functional agents onto zeolite for sodium dodecyl sulfate (SDS) sequestration in greywater reuse. We combine isothermal titration calorimetry (ITC) and quantum chemistry simulation (QCS) to identify the interactions between SDS and agents at the molecular level. Three potential agents, cetyl trimethyl ammonium bromide (CTAB), N,N,N-trimethyltetradecan-1-aminium bromide (C{sub 14}TAB), and 14-hydroxy-N,N,N-trimethyltetradecan-1-aminium bromide (C{sub 14}HTAB), differ in carbon chain length and hydrophilic groups. The ITC titration of SDS with CTAB released the highest heat, followed by those with C{sub 14}TAB and C{sub 14}HTAB, as was the same trend for the amounts of SDS adsorbed by the respective functionalized-zeolites. Results suggest that the favorable SDS sorption occurred at the bilayer CTAB-zeolite is driven by enthalpy as similar as the SDS…CTAB interaction found, regardless of the contribution from electrostatic and/or hydrophobic behaviors, while the declined sorption is entropy-driven via the predominant hydrophobic interaction onto the monolayer CTAB-zeolite. The data presented here interpret the nature of molecularly thermodynamic quantities and enable the manipulation of sorption capacity optimization.

Noncovalent binding of 4-nitroquinoline-N-oxide to proteins

International Nuclear Information System (INIS)

Yamamoto, Osamu

1979-01-01

Binding of 4NQO to various kinds of enzymes or proteins was studied. Each one of proteins was mixed with 4NQO in 0.4 mM NaHCO 3 solution and eluted through Ultrogel AcA 22 column. Radioactivity of 14 C-labeled 4NQO found in protein fraction was measured. 4NQO bound hardly to polyglutamic acid and polyaspertic acid, somewhat to serum albumin, insulin, trypsin, RNA polymerase and DNA polymerase, and markedly to ureas which is an SH enzyme. Lactate dehydrogenase, one of SH enzymes, aggregated with 4NQO. The binding of SH enzyme with the N-oxide would be attributable to a noncovalent binding such as >N-O---H-S-, because 4NQO-urease binding yield markedly decreased in the presence of sodium dodecyl sulfate or cysteine, and also 4NQO-bound urease released 4NQO by the addition of sodium dodecyl sulfate. (author)

Noncovalent binding of 4-nitroquinoline-N-oxide to proteins

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, O [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1979-12-01

Binding of 4NQO to various kinds of enzymes or proteins was studied. Each one of proteins was mixed with 4NQO in 0.4 mM NaHCO/sub 3/ solution and eluted through Ultrogel AcA 22 column. Radioactivity of /sup 14/C-labeled 4NQO found in protein fraction was measured. 4NQO bound hardly to polyglutamic acid and polyaspertic acid, somewhat to serum albumin, insulin, trypsin, RNA polymerase and DNA polymerase, and markedly to ureas which is an SH enzyme. Lactate dehydrogenase, one of SH enzymes, aggregated with 4NQO. The binding of SH enzyme with the N-oxide would be attributable to a noncovalent binding such as >N-O---H-S-, because 4NQO-urease binding yield markedly decreased in the presence of sodium dodecyl sulfate or cysteine, and also 4NQO-bound urease released 4NQO by the addition of sodium dodecyl sulfate.

NMR studies of the influence of dodecyl sulfate on the amide hydrogen exchange kinetics of a micelle-solubilized hydrophobic tripeptide

International Nuclear Information System (INIS)

O'Neil, J.D.J.; Sykes, B.D.

1989-01-01

Backbone amide hydrogen exchange measurements are an important source of information about the internal dynamics of proteins. Before such measurements can be interpreted unambiguously, contributions to hydrogen exchange rates from the chemical and physical environment of the amides must be taken into account. Membrane proteins are often solubilized in detergents, yet there have not been any systematic investigations of the possible effects detergents may have on the amide hydrogen exchange rates of proteins. To address this question, the authors have measured individual backbone and carboxyl-terminal amide exchange rates for the amphipathic tripeptide Leu-Val-Ile-amide dissolved in water and dodecyl sulfate micelles. Proton NMR spectroscopy was used to measure exchange using the direct exchange-out into D 2 O technique at 5 degree C and using an indirect steady-state saturation-transfer technique at 25 degree C. The broadening effect of micelle-incorporated spin-labeled fatty acid (12-doxylsterate) on the 1 H NMR spectra of both the detergent and the peptide resonances was used to demonstrate that the tripeptide is intimately associated with the micelle. These experiments help to explain the elevated pH min observed for backbone amides in the sodium dodecyl sulfate solubilized M13 coat protein

Cadmium Immobilization in Soil using Sodium Dodecyl Sulfate Stabilized Magnetite Nanoparticles

Directory of Open Access Journals (Sweden)

Ahmad Farrokhian Firouzi

2017-06-01

Full Text Available Introduction Some methods of contaminated soils remediation reduces the mobile fraction of trace elements, which could contaminate groundwater or be taken up by soil organisms. Cadmium (Cd as a heavy metal has received much attention in the past few decades due to its potential toxic impact on soil organism activity and compositions. Cadmium is a soil pollutant of no known essential biological functions, and may pose threats to soil-dwelling organisms and human health. Soil contamination with Cd usually originates from mining and smelting activities, atmospheric deposition from metallurgical industries, incineration of plastics and batteries, land application of sewage sludge, and burning of fossil fuels. Heavy metal immobilization using amendments is a simple and rapid method for the reduction of heavy metal pollution. One way of the assessment of contaminated soils is sequential extraction procedure. Sequential extraction of heavy metals in soils is an appropriate way to determine soil metal forms including soluble, exchangeable, carbonate, oxides of iron and manganese, and the residual. Its results are valuable in prediction of bioavailability, leaching rate and elements transformation in contaminated agricultural soils. Materials and Methods The objective of this study was to synthesize magnetite nanoparticles (Fe3O4 stabilized with sodium dodecyl sulfate (SDS and to investigate the effect of its different percentages (0, 1, 2.5, 5, and 10% on the different fractions of cadmium in soil by sequential extraction method. The nanoparticles were synthesized following the protocol described by Si et al. (19. The investigations were carried out with a loamy sand topsoil. Before use, the soil was air-dried, homogenized and sieved (

Enhancing Accuracy in Molecular Weight Determination of Highly Heterogeneously Glycosylated Proteins by Native Tandem Mass Spectrometry

NARCIS (Netherlands)

Wang, Guanbo; de Jong, Rob N; van den Bremer, Ewald T J; Parren, Paul W H I; Heck, Albert J R

2017-01-01

The determination of molecular weights (MWs) of heavily glycosylated proteins is seriously hampered by the physicochemical characteristics and heterogeneity of the attached carbohydrates. Glycosylation impacts protein migration during sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis

Preparation of Lignin/Sodium Dodecyl Sulfate Composite Nanoparticles and Their Application in Pickering Emulsion Template-Based Microencapsulation.

Science.gov (United States)

Pang, Yuxia; Wang, Shengwen; Qiu, Xueqing; Luo, Yanling; Lou, Hongming; Huang, Jinhao

2017-12-20

Lignin is a vastly underutilized biomass resource. The preparation of water-dispersed lignin nanoparticles is an effective way to realize the high-value utilization of lignin. However, the currently reported preparation methods of lignin nanoparticles still have some drawbacks, such as the requirement for toxic organic solvent or chemical modification, complicated operation process, and poor dispersibility. Here, lignin/sodium dodecyl sulfate (SDS) composite nanoparticles (LSNPs) with outstanding water dispersibility and a size range of 70-200 nm were facilely prepared via acidifying the mixed basic solution of alkaline lignin and SDS. No harsh chemical was needed. The formation mechanism was systematically studied. Results indicated that the LSNPs were obtained by acid precipitation of the mixed micelles formed by the self-assembly of lignin and SDS. In addition, on the basis of the LSNP-stabilized Pickering emulsions, lignin/polyurea composite microcapsules combining the excellent chemical stability of a synthetic polyurea shell with the fantastic antiphotolysis and antioxidant properties of lignin were successfully prepared.

SFG and SPR Study of Sodium Dodecyl Sulfate Film Assembly on Positively Charged Surfaces

Science.gov (United States)

Song, Sanghun; Weidner, Tobias; Wagner, Matthew; Castner, David

2012-02-01

This study uses sum frequency generation (SFG) vibrational spectroscopy and surface plasmon resonance (SPR) sensing to investigate the structure of sodium dodecyl sulfate (SDS) films formed on positively charged and hydrophilic surfaces. The SPR signals show a good surface coverage suggesting that full monolayer coverage is reached at 1 mM. SFG spectra of SDS adsorbed exhibits well resolved CH3 peaks and OH peaks. At both 0.2 mM and 1 mM SDS concentration the intensity of both the CH3 and OH peaks decreased close to background levels. We found that the loss of SFG signal at 0.2 mM occurs at this concentration independent of surface charge density. It is more likely that the loss of signal is related to structural inhomogeneity induced by a striped phase - stand-up phase transition. This is supported by a distinct change of the relative SFG phase between CH3/OH near 0.2 mM. The second intensity minimum might be related to charge compensation effects. We observed a substrate dependence for the high concentration transition. We also observed distinct SFG signal phase changes for water molecules associated with SDS layers at different SDS solution concentrations indicating that the orientation of bound water changed with SDS surface structure.

Use of sodium dodecyl sulfate pretreatment and 2-stage curing for improved quality of salted duck eggs.

Science.gov (United States)

Lian, Zixuan; Qiao, Longshan; Zhu, Guanghong; Deng, Yun; Qian, Bingjun; Yue, Jin; Zhao, Yanyun

2014-03-01

The effects of use of sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing on the microbial, physicochemical, and microstructural qualities of salted duck eggs were studied. After pretreatment in 0.5% (w/v) SDS solution at room conditions for 15 min, no discolorations were observed and no microorganisms were detected on the egg shells. In the 2-stage curing process, 25% (w/v) and 30% (w/v) saline solutions were evaluated in the 1st step (Stage I, approximately 18 d), whereas 4% (w/v) saline solution was applied in the 2nd step (Stage II, approximately 15 d). Along with increased curing time, water content decreased and NaCl content increased in the egg yolks from approximately 0.40% to 0.86%, whereas the water content of egg albumen remained at approximately 85% during the 2-stage curing. More importantly, the NaCl content of albumen maintained at approximately 4.0% at Stage II curing. Yolk index as a sign of maturity for salted duck eggs reached 1 at the end of Stage I (18 d) and retained the same value during Stage II curing regardless of the NaCl concentration in the Stage I saline solution. Oil exudation in egg yolks increased as the time of curing increased. As seen from scanning electron microscopy, oil was released from yolk granules. This study indicated that SDS pretreatment is effective to reduce microbial load on the shells of fresh duck eggs and the 2-stage curing can improve physicochemical qualities of the salted duck eggs and shortened curing time to about 7 to 17 d as compared to the traditional 1-step curing method. Spoiled saline solution and uneven distribution of salt are the 2 major problems in producing salted duck eggs. Sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing process have shown effective to solve these problems, respectively. The SDS pretreatment was able to remove microorganisms and soil from the surface of fresh egg shells, thus preventing the spoilage of the saline solution. The 2-stage curing process

Impact of sodium dodecyl sulphate on the dissolution of poorly soluble drug into biorelevant medium from drug-surfactant discs

DEFF Research Database (Denmark)

Madelung, Peter; Ostergaard, Jesper; Bertelsen, Poul

2014-01-01

The purpose was to elucidate the mechanism of action of sodium dodecyl sulphate (SDS) on drug dissolution from discs under physiologically relevant conditions. The effect of incorporating SDS (4-30%, w/w) and drug into discs on the dissolution constant and solubility were evaluated for the poorly...... soluble drugs griseofulvin and felodipine in a biorelevant dissolution medium (BDM). Dissolution constants from dissolution profiles of drug discs with and without SDS were measured using miniaturized rotating disc dissolution. Solid state changes were investigated by X-ray diffraction. Solubility...... showed that the addition of SDS made the BS:PC micelles grow up to 2.5 times in volume. As a function of SDS addition, the dissolution constant showed an apparent exponential increase, while drug solubility showed a weak linear dependence. The pronounced effect on dissolution constant with SDS...

Ecotoxicological assessment of the pharmaceutical fluoxetine hydrochloride and the surfactant dodecyl sodium sulfate after their submission to ionizing radiation treatment

International Nuclear Information System (INIS)

Santos, Dymes Rafael Alves dos

2011-01-01

The use of pharmaceuticals and personal care products and the consequent and continuous input of this substances in the environment generates an increasing need to investigate the presence, behavior and the effects on aquatic biota, as well as new ways to treat effluents containing such substances. Fluoxetine hydrochloride is an active ingredient used in the treatment of depressive disorders and anxiety. As the surfactant sodium dodecyl sulfate is present in many cleaning and personal care products. The present study aimed on assessing the acute toxicity of fluoxetine hydrochloride, sodium dodecyl sulfate and the mixture of both to the aquatic organisms Hyalella azteca, Daphnia similis and Vibrio ficheri. Reducing the toxicity of fluoxetine and the mixture after treatment with ionizing radiation from industrial electron beam accelerator has also been the focus of this study. For Daphnia similis the average values of CE50-4 8h found for the non-irradiated drug, surfactant and mixture were 14.4 %, 9.62 % and 13.8 %, respectively. After irradiation of the substances, the dose 5 kGy proved itself to be the most effective dose for the treatment of the drug and the mixture as it was obtained the mean values for CE50 48h 84.60 % and > 90 %, respectively. For Hyalella azteca the acute toxicity tests were performed for water column with duration of 96 hours, the mean values for CE50 96h found for the drug, the surfactant and the mixture non-irradiated were 5.63 %, 19.29 %, 6.27 %, respectively. For the drug fluoxetine and the mixture irradiated with 5 kGy, it was obtained 69.57 % and 77.7 %, respectively. For Vibrio ficheri the acute toxicity tests for the untreated drug and the drug irradiated with 5 kGy it was obtained CE50 15min of 6.9 % and 32.88 % respectively. These results presented a reduction of the acute toxicity of the test-substances after irradiation. (author)

Molecular Insight into Human Lysozyme and Its Ability to Form Amyloid Fibrils in High Concentrations of Sodium Dodecyl Sulfate: A View from Molecular Dynamics Simulations.

Directory of Open Access Journals (Sweden)

Majid Jafari

Full Text Available Changes in the tertiary structure of proteins and the resultant fibrillary aggregation could result in fatal heredity diseases, such as lysozyme systemic amyloidosis. Human lysozyme is a globular protein with antimicrobial properties with tendencies to fibrillate and hence is known as a fibril-forming protein. Therefore, its behavior under different ambient conditions is of great importance. In this study, we conducted two 500000 ps molecular dynamics (MD simulations of human lysozyme in sodium dodecyl sulfate (SDS at two ambient temperatures. To achieve comparative results, we also performed two 500000 ps human lysozyme MD simulations in pure water as controls. The aim of this study was to provide further molecular insight into all interactions in the lysozyme-SDS complexes and to provide a perspective on the ability of human lysozyme to form amyloid fibrils in the presence of SDS surfactant molecules. SDS, which is an anionic detergent, contains a hydrophobic tail with 12 carbon atoms and a negatively charged head group. The SDS surfactant is known to be a stabilizer for helical structures above the critical micelle concentration (CMC [1]. During the 500000 ps MD simulations, the helical structures were maintained by the SDS surfactant above its CMC at 300 K, while at 370 K, human lysozyme lost most of its helices and gained β-sheets. Therefore, we suggest that future studies investigate the β-amyloid formation of human lysozyme at SDS concentrations above the CMC and at high temperatures.

Foam capacity and stability of Sodium Dodecyl Sulfate (SDS) on the presence of contaminant coffee and Cd ions in solution

Science.gov (United States)

Haryanto, B.; Chang, C. H.; Kuo, A. T.; Siswarni, M. Z.; Sinaga, T. M. A.

2018-02-01

In this study, the effect of the coffee colloidal particle and Cd ion contaminant on the foam capacity and stability of sodium dodecyl sulfate (SDS) solution was investigated. The foam was generated by using a foam generator. The foam capacity of SDS was first evaluated at different concentrations. After the foam capacity reaching a constant value, the foam stability was then measured by flowing to a column. The results showed that the presence the coffee colloidal particles or Cd ions in the solution would decrease the foam capacity and stability of SDS. In addition, the decreased foam capacity and stability was more pronounced in the presence of coffee colloidal particles than Cd ions. The colloidal particles may have stronger interaction with SDS and thus reduce the formation of the foam.

Investigation of structure and magnetic properties of cobalt-nickel and manganese ferrites nanoparticles synthesized in direct micelles of sodium dodecyl sulphate system

International Nuclear Information System (INIS)

Fedosyuk, V.M.; Mirgorod, Yu.A.

2016-01-01

Results of investigation of the crystal structure and magnetic properties of the nanoparticles of transition metals ferrites (cobalt, nickel, manganese) synthesized by unified methods using direct sodium dodecyl sulfate micelles are presented. Crystal structure of the samples was investigated by X-ray diffraction on DRON-3M (in the CuKa-radiation). Particle size was investigated by transmission electron microscopy on microscope JEOL JEM-1011 (accelerating voltage 100 kV). All powders contain nanoparticles of the same size in the range 2-6 nm. Magnetic properties of the samples were estimated from temperature and field dependences of the magnetization. All samples exhibit properties of superparamagnets with different blocking temperatures below 45 K. (authors).

Induction and characterization of pathogenesis-related proteins in ...

African Journals Online (AJOL)

Furthermore, induced proteins were extracted from roots of inoculated and control tolerant (RO1054 and RO3015) and susceptible (RO2063) accessions at 8 dpi, and characterized by isoelectric focusing (IEF), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analyses. Chitinase ...

Role of dietary supplementation in the protein content of bovine milk ...

African Journals Online (AJOL)

Feed back response of the caseins and whey proteins was observed in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profile by resolving these proteins upon 15% SDS PAGE which showed remarkable variation in the banding pattern of all caseins i.e., α-caseins, β-caseins, κ-casein and whey ...

Interactions between Surfactants in Solution and Electrospun Protein Fibers: Effects on Release Behavior and Fiber Properties

DEFF Research Database (Denmark)

Boutrup Stephansen, Karen; García-Díaz, María; Jessen, Flemming

2016-01-01

, and drug delivery. In the present study, we present a systematic investigation of how surfactants and proteins, as physiologically relevant components, interact with insulin-loaded fish sarcoplasmic protein (FSP) electrospun fibers (FSP-Ins fibers) in solution and thereby affect fiber properties...... such as accessible surface hydrophilicity, physical stability, and release characteristics of an encapsulated drug. Interactions between insulin-loaded protein fibers and five anionic surfactants (sodium taurocholate, sodium taurodeoxycholate, sodium glycocholate, sodium glycodeoxycholate, and sodium dodecyl sulfate......Intermolecular interaction phenomena occurring between endogenous compounds, such as proteins and bile salts, and electrospun compounds are so far unreported, despite the exposure of fibers to such biorelevant compounds when applied for biomedical purposes, e.g., tissue engineering, wound healing...

An electrochemical sensor for sodium dodecyl sulfate detection based on anion exchange using eosin Y/polyethyleneimine modified electrode.

Science.gov (United States)

Hao, Xia; Lei, Jing Lei; Li, Nian Bing; Luo, Hong Qun

2014-12-10

A simple and effective method for the detection of electrochemically inactive sodium dodecyl sulfate (SDS) has been designed, based on different binding affinity of polyethyleneimine (PEI) toward electrochemically active eosin Y and electrochemically inactive SDS. The stronger binding affinity of the PEI toward SDS than eosin Y results in the decrease of the redox peak current of surface confined eosin Y and provides a quantitative readout for the SDS. The difference in value of the cathodic peak current showed a linear relationship with SDS concentration in a concentration range from 1 to 40 μg mL(-1), and a detection limit of 0.9 μg mL(-1) for SDS was obtained. Furthermore, the method has been successfully applied to the detection of SDS in real samples. The developed approach provided a simple and reliable detection for SDS and might have potential applications in electrochemical methods for inactive molecules. Copyright © 2014 Elsevier B.V. All rights reserved.

A comparative study on production of stable carbon nano tube dispersions using gum arabic and sodium dodecyl sulphate

International Nuclear Information System (INIS)

Rashmi, W.; Ismail, A.F.; Jameel, A.T.; Yusof, F.; Khalid, M.; Mubarak, N.M.

2009-01-01

Full text: Improvements on the stability of carbon nano tube (CNT)-water suspensions are necessary to enhance the performance of CNT nano fluids. CNTs are usually packed into crystalline ropes that form strong networks due to Van der Waals attraction. Aggregation of these CNTs is obstacle to most of the applications which diminished its special properties. Thus, this paper aims to produce stable CNT dispersion using Gum Arabic (GA) and Sodium dodecyl sulphate (SDS) as dispersants. The CNT concentration is varied from 0.01-0.1 wt% while the concentration of dispersants is varied from 1-12 wt%, respectively. This work gives detailed information on effect of CNT concentration, dispersant concentration and sonication time on stability of CNT dispersions. UV-Vis Spectrophotometer was used to measure the concentration of CNTs with respect to sedimentation time. CNT-GA suspensions were found to be more stable compared to CNT-SDS suspensions. The homogeneous suspension of CNT-GA is stable for several months. (author)

pH-dependent differential interacting mechanisms of sodium dodecyl sulfate with bovine serum fetuin: a biophysical insight.

Science.gov (United States)

Zaidi, Nida; Nusrat, Saima; Zaidi, Fatima Kamal; Khan, Rizwan H

2014-11-20

Sodium dodecyl sulfate (SDS)-glycoprotein interaction serves as a model for a biological membrane. To get mechanistic insight into the interaction of SDS and glycoprotein, the effect of SDS on bovine serum fetuin (BSF) was studied in subcritical micellar concentrations at pH 7.4 and pH 2 using multiple approaches. SDS interacts electrostatically with BSF through its negatively charged head groups at pH 2 and hydrophobically via its alkyl chains at pH 7.4 up to a 1:20 molar ratio of BSF to SDS. However, at higher concentrations of SDS, BSF undergoes amyloid fibril formation at pH 2, as confirmed by enhanced ThT fluorescence, β-sheet formation, and TEM microscopy, whereas BSF undergoes induction of an α-helical structure in the presence of higher SDS concentration at pH 7.4. The increase in α-helical content with increasing SDS concentrations constrains the environment around tryptophan. As a consequence, the interconversion of tryptophan conformers decreases, resulting in a decrement of the fluorescence lifetime for BSF in the presence of SDS at pH 7.4.

Temporal and geographical distributions of epilithic sodium dodecyl sulfate-degrading bacteria in a polluted South Wales river

Energy Technology Data Exchange (ETDEWEB)

Anderson, D.J.; Day, M.J.; Russell, N.J.; White, G.F.

1988-02-01

Epilithic bacteria were isolated nonselectively from riverbed stones and examined by gel zymography for their ability to produce alkylsulfatase (AS) enzymes and thus to metabolize alkyl sulfate surfactants such as sodium dodecyl sulfate. The percentages of AS+ isolates from stone epilithon at five sites from the source to the river mouth were measured on five sampling days spread over 1 year. The results showed that (i) the prevalence of epilithic AS+ strains (as a percentage of all isolates) was much higher at polluted sites than at the source; (ii) when averaged over the whole river, percentages of AS+ strains were significantly higher at the end of summer compared with either the preceding or the following winter; (iii) analysis of site-sampling time interactions indicated that water quality factors (e.g., biochemical oxygen demand and dissolved oxygen concentration) rather than climatic factors determined the distributions of epilithic AS+ isolates; (iv) constitutive strains were the most prevalent (7.2% of all isolates), with smaller numbers of isolates with inducible (4.5%) and repressible (1.7%) enzymes.

Conformational studies of human [15-2-aminohexanoic acid]little gastrin in sodium dodecyl sulfate micelles by 1H NMR

International Nuclear Information System (INIS)

Mammi, S.; Peggion, E.

1990-01-01

Human little gastrin is a 17 amino acid peptide that adopts a random conformation in water and an ordered structure in sodium dodecyl sulfate (SDS) micelles as well as in trifluoroethanol (TFE). The circular dichroism spectra in these two media have the same shape, indicative of a similar preferred conformation. The authors describe here the assignment of the proton NMR resonances and the conformational analysis of [Ahx 15 ] little gastrin in SDS micelles. Two-dimensional correlation techniques form the basis for the assignment. The conformational analysis utilizes NOE's, NH to C α H coupling constants, and the temperature coefficients of the amide chemical shifts. The NMR data indicate a helical structure in the N-terminal portion of the peptide. These results are compared with the conformation that the authors recently proposed for a minigastrin analogue (fragment 5-17 of [Ahx 15 ] little gastrin) in TFE

Extraction of Jatropha curcas proteins and application in polyketone-based wood adhesives

NARCIS (Netherlands)

Hamarneh, A. I.; Heeres, H. J.; Broekhuis, A. A.; Picchioni, F.

2010-01-01

Jatropha proteins were successfully extracted from the corresponding seeds using the principle of isoelectric precipitation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), elemental analysis and Fourier transform infrared spectroscopy (FTIR) were used to analyze the obtained

Fast Removal of Citalopram Drug from Waste Water Using Magnetic Nanoparticles Modified with Sodium Dodecyl Sulfate Followed by UV-Spectrometry

Directory of Open Access Journals (Sweden)

M. Khoeini Sharifabadi

2014-02-01

Full Text Available A simple and sensitive, solid-phase extraction method for the removal of Citalopram drug from waste water has been developed by using magnetic nanoparticles modified with surfactant sodium dodecyl sulfate. These magnetic nanoparticles have shown great adsorptive tendency towards Citalopram drug. The effect of different parameters influencing the extraction efficiency of this drug were investigated and optimized including the pH, amount of the surfactant, contact time and temperature. The extracts were analyzed by ultraviolet spectrophotometry at 239nm. Under these conditions, the related standard deviation (RSD % of the method at two concentrations (5 and 50µg.mL-1 was in the range of (3.14–3.75 % (n = 8. The calibration curve was linear in the range of 2-100 µg.mL-1 of Citalopram drug with a correlation coefficient of >0.99.

Fast Removal of Citalopram Drug from Waste Water Using Magnetic Nanoparticles Modified with Sodium Dodecyl Sulfate Followed by UV-Spectrometry

Directory of Open Access Journals (Sweden)

M. Khoeini Sharifabadi

2013-04-01

Full Text Available A simple and sensitive, solid-phase extraction method for the removal of Citalopram drug from waste water has been developed by using magnetic nanoparticles modified with surfactant sodium dodecyl sulfate. These magnetic nanoparticles have shown great adsorptive tendency towards Citalopram drug. The effect of different parameters influencing the extraction efficiency of this drug were investigated and optimized including the pH, amount of the surfactant, contact time and temperature. The extracts were analyzed by ultraviolet spectrophotometry at 239nm. Under these conditions, the related standard deviation (RSD % of the method at two concentrations (5 and 50µg.mL-1 was in the range of (3.14–3.75 % (n = 8. The calibration curve was linear in the range of 2-100 µg.mL-1 of Citalopram drug with a correlation coefficient of >0.99.

Micellar solubilization in strongly interacting binary surfactant systems. [Binary surfactant systems of: dodecyltrimethylammonium chloride + sodium dodecyl sulfate; benzyldimethyltetradecylammonium chloride + tetradecyltrimethylammonium chloride

Energy Technology Data Exchange (ETDEWEB)

Treiner, C. (Universite Pierre et Marie Curie, Paris (France)); Nortz, M.; Vaution, C. (Faculte de Pharmacie de Paris-sud, Chatenay-Malabry (France))

1990-07-01

The apparent partition coefficient P of barbituric acids between micelles and water has been determined in mixed binary surfactant solutions from solubility measurements in the whole micellar composition range. The binary systems chosen ranged from the strongly interacting system dodecyltrimethylammonium chloride + sodium dodecyl sulfate to weakly interacting systems such as benzyldimethyltetradecylammonium chloride + tetradecyltrimethyammonium chloride. In all cases studied, mixed micelle formation is unfavorable to micellar solubilization. A correlation is found between the unlike surfactants interaction energy, as measured by the regular solution parameter {beta} and the solute partition coefficient change upon surfactant mixing. By use of literature data on micellar solubilization in binary surfactant solutions, it is shown that the change of P for solutes which are solubilized by surface adsorption is generally governed by the sign and amplitude of the interaction parameter {beta}.

Interactions between Surfactants in Solution and Electrospun Protein Fibers: Effects on Release Behavior and Fiber Properties

DEFF Research Database (Denmark)

Boutrup Stephansen, Karen; García-Díaz, María; Jessen, Flemming

2016-01-01

, and drug delivery. In the present study, we present a systematic investigation of how surfactants and proteins, as physiologically relevant components, interact with insulin-loaded fish sarcoplasmic protein (FSP) electrospun fibers (FSP-Ins fibers) in solution and thereby affect fiber properties...... such as accessible surface hydrophilicity, physical stability, and release characteristics of an encapsulated drug. Interactions between insulin-loaded protein fibers and five anionic surfactants (sodium taurocholate, sodium taurodeoxycholate, sodium glycocholate, sodium glycodeoxycholate, and sodium dodecyl sulfate......), a cationic surfactant (benzalkonium chloride), and a neutral surfactant (Triton X-100) were studied. The anionic surfactants increased the insulin release in a concentration-dependent manner, whereas the neutral surfactant had no significant effect on the release. Interestingly, only minute amounts...

Detection of protein kinase activity by renaturation in sodium dodecyl sulfate-polyacrylamide gels

International Nuclear Information System (INIS)

Anostario, M. Jr.; Harrison, M.L.; Geahlen, R.L.

1986-01-01

The authors have developed a procedure for identifying protein kinase activity in protein samples following electrophoresis on SDS-polyacrylamide gels. Proteins are allowed to renature directly in the gel by removal of detergent. The gel is then incubated with [γ- 32 P]ATP to allow renatured protein kinases to autophosphorylate or to phosphorylate various substrates which can be incorporated into the gel. The positions of the radiolabeled proteins can then be detected by autoradiography. With this technique, using purified catalytic subunit of cAMP-dependent protein kinase, enzyme concentrations as low as 0.01 μg can be detected on gels containing 1.0 mg/ml casein. The procedure is also applicable for the determination of active subunits of multisubunit protein kinases. For example, when the two subunits of casein kinase II are separated by SDS-polyacrylamide gel electrophoresis and allowed to renature, only the larger α subunit shows activity. This procedure can also be used to detect and distinguish kinases present in heterogeneous mixtures. Starting with a particulate fraction from LSTRA, a murine T cell lymphoma, several distinct enzymes were detected, including a 30,000 Dalton protein with protein-tyrosine kinase activity. This same enzyme has also been detected in T lymphocytes and other T lymphoid cell lines

Determination of antihypertensive drug moexipril hydrochloride based on the enhancement effect of sodium dodecyl sulfate at carbon paste electrode.

Science.gov (United States)

Attia, Ali K

2010-04-15

Herein, an electrochemical differential pulse voltammetric method was developed for the determination of moexipril hydrochloride based on the enhancement effect of sodium dodecyl sulfate. The oxidation process has been carried out in Britton-Robinson buffer. Moexipril hydrochloride exhibits a well-defined irreversible oxidation peak over the entire pH range (2-11). The peak current varied linearly over the range from 4.0 x 10(-7) to 5.2 x 10(-6) mol L(-1). The limits of detection and quantification were 6.87 x 10(-8) mol L(-1) and 2.29 x 10(-7) mol L(-1), respectively. The recovery was found in the range from 99.65% to 100.76%. The relative standard deviation was found in the range from 0.429% to 0.845%. The proposed method possesses high sensitivity, accuracy and rapid response. Finally, this method was successfully used to determine moexipril hydrochloride in tablets. (c) 2009 Elsevier B.V. All rights reserved.

Wheat IgE-mediated food allergy in European patients: alpha-amylase inhibitors, lipid transfer proteins and low-molecular-weight glutenins

DEFF Research Database (Denmark)

Pastorello, Elide A; Farioli, Laura; Conti, Amedeo

2007-01-01

for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross...

Cross reaction between P-61 sunflower seedlings oleosomal protein ...

African Journals Online (AJOL)

A true triacylglycerol lipase was detected in germinating sunflower (Helianthus annuus L.) seedlings associated to oleosomes. This enzyme that has not yet been identified was partially purified as shown by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) (10%); two protein bands, P-61 and P-66 ...

Evaluation of BacT/Alert 3D Liquid Culture System for Recovery of Mycobacteria from Clinical Specimens Using Sodium Dodecyl (Lauryl) Sulfate-NaOH Decontamination

Science.gov (United States)

Carricajo, A.; Fonsale, N.; Vautrin, A. C.; Aubert, G.

2001-01-01

A total of 52 mycobacterial isolates were recovered from 1,197 clinical specimens decontaminated by a sodium dodecyl (lauryl) sulfate (SDS)-NaOH protocol. Of these, 94% were recovered with the BacT/Alert 3D system (Organon Teknika, Durham, N.C.) and 79% were recovered on Löwenstein-Jensen (LJ) medium. Mean times to detection of organisms of the Mycobacterium tuberculosis complex (n = 47) were 22.8 days with LJ medium and 16.2 days with the system. The BacT/Alert 3D system is a rapid and efficient detection system which can be used with an SDS-NaOH decontamination procedure. PMID:11574623

The Effect of Sodium Dodecyl Sulfate (SDS and Cetyltrimethylammonium Bromide (CTAB on the Properties of ZnO Synthesized by Hydrothermal Method

Directory of Open Access Journals (Sweden)

Yun Hin Taufiq-Yap

2012-10-01

Full Text Available ZnO nanostructures were synthesized by hydrothermal method using different molar ratios of cetyltrimethylammonium bromide (CTAB and Sodium dodecyl sulfate (SDS as structure directing agents. The effect of surfactants on the morphology of the ZnO crystals was investigated by field emission scanning electron microscopy (FESEM and transmission electron microscopy (TEM techniques. The results indicate that the mixture of cationic-anionic surfactants can significantly modify the shape and size of ZnO particles. Various structures such as flakes, sheets, rods, spheres, flowers and triangular-like particles sized from micro to nano were obtained. In order to examine the possible changes in other properties of ZnO, characterizations like powder X-ray diffraction (PXRD, thermogravimetric and differential thermogravimetric analysis (TGA-DTG, FTIR, surface area and porosity and UV-visible spectroscopy analysis were also studied and discussed.

Maternal serum protein profile and immune response protein subunits as markers for non-invasive prenatal diagnosis of trisomy 21, 18, and 13

KAUST Repository

Narasimhan, Kothandaraman

2013-02-01

Objectives: To use proteomics to identify and characterize proteins in maternal serum from patients at high-risk for fetal trisomy 21, trisomy 18, and trisomy 13 on the basis of ultrasound and maternal serum triple tests. Methods: We performed a comprehensive proteomic analysis on 23 trisomy cases and 85 normal cases during the early second trimester of pregnancy. Protein profiling along with conventional sodium dodecyl sulfate polyacrylamide gel electrophoresis/Tandem mass spectrometry analysis was carried out to characterize proteins associated with each trisomy condition and later validated using Western blot. Results: Protein profiling approach using surface enhanced laser desorption/ionization time-of-flight mass (SELDI-TOF/MS) spectrometry resulted in the identification of 37 unique hydrophobic proteomic features for three trisomy conditions. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by Matrix Assisted Laser Desorption Ionization - Time of Flight/Time of Flight (MALDI-TOF/TOF) and western blot, glyco proteins such as alpha-1-antitrypsin, apolipoprotein E, apolipoprotein H, and serum carrier protein transthyretin were identified as potential maternal serum markers for fetal trisomy condition. The identified proteins showed differential expression at the subunit level. Conclusions: Maternal serum protein profiling using proteomics may allow non-invasive diagnostic testing for the most common trisomies and may complement ultrasound-based methods to more accurately determine pregnancies with fetal aneuploidies. © 2013 John Wiley & Sons, Ltd.

Size exclusion HPLC of proteins for evaluation of durum wheat quality

Science.gov (United States)

The present research aimed to assess size exclusion HPLC (SE-HPLC) in protein molecular weight distribution determination for quality evaluation of durum semolina. Semolina samples were milled from 13 durum genotypes grown at 7 locations in 2009 and 2010 in ND. Sodium dodecyl sulfate (SDS) buffer ...

Two Dimensional Electrophoresis of Proteins from Cultures of Erysiphe graminis f.sp. hordei

DEFF Research Database (Denmark)

Torp, J.; Andersen, Brian

1982-01-01

Conidial proteins from barley powdery mildew, Erysiphe graminis f. sp. hordei, were separated by 2-dimensional electrophoresis in polyacrylamide slab gels. Isoelectric focusing was used in the first dimension and separation according to molecular weight in a gel containing sodium dodecyl sulphate...

Surface peptide mapping of protein I and protein III of four strains of Neisseria gonorrhoeae

International Nuclear Information System (INIS)

Judd, R.C.

1982-01-01

Whole cells and isolated outer membranes (OMs) of four strains of gonococci were surface radioiodinated with either lactoperoxidase or Iodogen (Pierce Chemical Co., Rockford, Ill.). These preparations were solubilized in sodium dodecyl sulfate and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Surface-radioiodinated protein I (PI) and PIII bands were excised from the sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels and digested with alpha-chymotrypsin, and the resultant 125 I-peptide fragments were resolved by high-voltage electrophoresis and thin-layer chromatography (i.e., surface peptide mapping). Radioemitting peptidic fragments were visualized by autoradiography. Results demonstrated that the PI molecule of each gonococcal strain studied had unique iodinatable peptides exposed on the surface of whole cells and OMs, whereas PIIIs appeared to have the same portion of the molecule exposed on the surface of bacteria or OMs, regardless of the gonococcal strain from which they were isolated. Many more radiolabeled peptides were seen in surface peptide maps of PIs from radiolabeled OMs than in those from radioiodinated whole cells, whereas different peptidic fragments were seen in the surface peptide maps of PIIIs from radiolabeled OMs than were seen in those from radiolabeled whole cells. These data suggest that PI may contribute strain-specific antigenic determinants and PIII may contribute cross-reactive determinants and that the surface exposure of PI and PIII is different in isolated OMs than in the OM of intact gonococci

Fast mapping of global protein folding states by multivariate NMR:

DEFF Research Database (Denmark)

Malmendal, Anders; Underhaug, Jarl; Otzen, Daniel

2010-01-01

To obtain insight into the functions of proteins and their specific roles, it is important to establish efficient procedures for exploring the states that encapsulate their conformational space. Global Protein folding State mapping by multivariate NMR (GPS NMR) is a powerful high-throughput method......-lactalbumin in the presence of the anionic surfactant sodium dodecyl sulfate, SDS, and compare these with other surfactants, acid, denaturants and heat....

Sodium dodecyl sulfate coated alumina modified with a new Schiff's base as a uranyl ion selective adsorbent

Energy Technology Data Exchange (ETDEWEB)

Tashkhourian, J., E-mail: tashkhourian@susc.ac.ir [Department of Chemistry, College of Science, Shiraz University, 71454 Shiraz (Iran, Islamic Republic of); Moradi Abdoluosofi, L.; Pakniat, M. [Department of Chemistry, Faculty of Science, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of); Montazerozohori, M. [Department of Chemistry, Faculty of Science, Yasouj University, Yasouj (Iran, Islamic Republic of)

2011-03-15

A simple and selective method was used for the preconcentration and determination of uranium(VI) by solid-phase extraction (SPE). In this method, a column of alumina modified with sodium dodecyl sulfate (SDS) and a new Schiff's base ligand was prepared for the preconcentration of trace uranyl(VI) from water samples. The uranium(VI) was completely eluted with HCl 2 M and determined by a spectrophotometeric method with Arsenazo(III). The preconcentration steps were studied with regard to experimental parameters such as amount of extractant, type, volume and concentration of eluent, pH, flow rate of sample source and tolerance limit of diverse ions on the recovery of uranyl ion. A preconcentration factor more than 200 was achieved and the average recovery of uranyl(VI) was 99.5%. The relative standard deviation was 1.1% for 10 replicate determinations of uranyl(VI) ion in a solution with a concentration of 5 {mu}g mL{sup -1}. This method was successfully used for the determination of spiked uranium in natural water samples.

Proteomic analysis of cell surface-associated proteins from probiotic Lactobacillus plantarum

DEFF Research Database (Denmark)

Beck, Hans Christian; Madsen, Søren M; Glenting, Jacob

2009-01-01

In the present study, we used a proteomic approach to identify surface-associated proteins from the probiotic bacterium Lactobacillus plantarum 299v. Proteins were extracted from the cell surface using a mild wash in phosphate buffer and analysed by sodium dodecyl sulphate-polyacrylamide gel...... of probiotics in the gastrointestinal tract. The results provide the basis for future studies on the molecular mechanisms of probiotics....

Effect of sodium ascorbate and sodium nitrite on protein and lipid oxidation in dry fermented sausages.

Science.gov (United States)

Berardo, A; De Maere, H; Stavropoulou, D A; Rysman, T; Leroy, F; De Smet, S

2016-11-01

The effects of sodium nitrite and ascorbate on lipid and protein oxidation were studied during the ripening process of dry fermented sausages. Samples were taken at day 0, 2, 8, 14, 21 and 28 of ripening to assess lipid (malondialdehyde) and protein (carbonyls and sulfhydryl groups) oxidation. Sodium ascorbate and nitrite were separately able to reduce the formation of malondialdehyde. Their combined addition resulted in higher amounts of carbonyl compounds compared to their separate addition or the treatment without any of both compounds. Moreover, sodium nitrite limited the formation of γ-glutamic semialdehyde whereas sodium ascorbate showed a pro-oxidant effect. A loss of thiol groups was observed during ripening, which was not affected by the use of sodium ascorbate nor sodium nitrite. In conclusion, sodium nitrite and ascorbate affected protein and lipid oxidation in different manners. The possible pro-oxidant effect of their combined addition on carbonyl formation might influence the technological and sensory properties of these products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of low concentration sodium dodecyl sulfate on the electromigration of palonosetron hydrochloride stereoisomers in micellar electrokinetic chromatography.

Science.gov (United States)

Hu, Shao-Qiang; Wang, Gui-Xia; Guo, Wen-Bo; Guo, Xu-Ming; Zhao, Min

2014-05-16

The effect of low concentrations of sodium dodecyl sulfate (SDS) on the separation of palonosetron hydrochloride (PALO) stereoisomers by micellar electrokinetic chromatography (MEKC) has been investigated. It was found that the addition of SDS prolongs the migration time and the migration order of four stereoisomers changes regularly with the SDS concentration. Good separations for all the four stereoisomers were achieved at appropriate SDS concentration. The effect of SDS on the electromigration (mobilities) of PALO stereoisomers has been studied, in order to explain its effect on the separation by MEKC. It was found that low concentrations of SDS added into the separation media forms negatively charged complexes with PALO stereoisomers and hence reverses their electromigration direction. Furthermore, the migration order between two enantiomeric pairs is also reversed because the enantiomeric pair with a bigger positive mobility than that of another pair turns to have a bigger negative mobility when bound with SDS. Based on these results, the effect of SDS on the MEKC separation of PALO stereoisomers was elucidated reasonably. The performance of the developed chiral MEKC method was validated by the analysis of a real sample. Copyright © 2014 Elsevier B.V. All rights reserved.

Adsorption of mixtures of poly(amidoamine) dendrimers and sodium dodecyl sulfate at the air-water interface.

Science.gov (United States)

Arteta, Marianna Yanez; Campbell, Richard A; Nylander, Tommy

2014-05-27

We relate the adsorption from mixtures of well-defined poly(amidoamine) (PAMAM) dendrimers of generations 4 and 8 with sodium dodecyl sulfate (SDS) at the air-water interface to the bulk solution properties. The anionic surfactant shows strong attractive interactions with the cationic dendrimers at pH 7, and electrophoretic mobility measurements indicate that the association is primarily driven by electrostatic interactions. Optical density measurements highlight the lack of colloidal stability of the formed bulk aggregates at compositions close to charge neutrality, the time scale of which is dependent on the dendrimer generation. Adsorption at the air-water interface was followed from samples immediately after mixing using a combination of surface tension, neutron reflectometry, and ellipsometry measurements. In the phase separation region for dendrimers of generation 4, we observed high surface tension corresponding to a depleted surfactant solution but only when the aggregates carried an excess of surfactant. Interestingly, these depleted adsorption layers contained spontaneously adsorbed macroscopic aggregates, and these embedded particles do not rearrange to spread monomeric material at the interface. These findings are discussed in relation to the interfacial properties of mixtures involving dendrimers of generation 8 as well as polydisperse linear and hyperbranched polyelectrolytes where there is polyelectrolyte bound to a surfactant monolayer. The results presented here demonstrate the capability of dendrimers to sequester anionic surfactants in a controllable manner, with potential applications as demulsification and antifoaming agents.

Dynamic changes in proteins during apple (Malus x domestica) fruit ripening and storage

OpenAIRE

Shi, Yun; Jiang, Li; Zhang, Li; Kang, Ruoyi; Yu, Zhifang

2014-01-01

A proteomic study, using two-dimensional polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight, was conducted in apple fruit (cv. ‘Golden Delicious’) starting at 10 days prior to harvest through 50 days in storage. Total protein was extracted using a phenol/sodium dodecyl sulfate protocol. More than 400 protein spots were detected in each gel and 55 differentially expressed proteins (p

Thermochemistry of the Dissolution of Dipeptides Containing DL-α-Alanine in Aqueous Solutions of Sodium Dodecyl Sulfate at 298.15 K

Science.gov (United States)

Smirnov, V. I.; Badelin, V. G.

2018-05-01

Enthalpies of the dissolution of DL-α-alanylglycine (AlaGly), DL-α-alanyl-DL-α-alanine (AlaAla), DL-α-alanyl-DL-α-valine (AlaVal), and DL-α-alanyl-DL-norleucine (AlaNln) in an aqueous solution of sodium dodecyl sulfate (SDS) at SDS concentration of m = 0-0.07 mol kg-1 and temperature T = 298.15 K are measured via calorimetry. The standard values of the enthalpy of dissolution (Δsol H m ) and the transfer of dipeptides (Δtr H m ) from water to aqueous SDS solutions are calculated using the experimental data. The dependences of Δsol H m and Δtr H m the SDS concentration at a constant concentration of dipeptide are established. Thermochemical characteristics of the transfer of AlaGly, AlaAla, AlaVal, and AlaNln in the investigated range of SDS concentrations are compared. The results are interpreted by considering ion-ion, ion-polar, and hydrophobic-hydrophobic interactions between SDS and dipeptide molecules.

Metabolic behavior of cell surface biotinylated proteins

International Nuclear Information System (INIS)

Hare, J.F.; Lee, E.

1989-01-01

The turnover of proteins on the surface of cultured mammalian cells was measured by a new approach. Reactive free amino or sulfhydryl groups on surface-accessible proteins were derivatized with biotinyl reagents and the proteins solubilized from culture dishes with detergent. Solubilized, biotinylated proteins were then adsorbed onto streptavidin-agarose, released with sodium dodecyl sulfate and mercaptoethanol, and separated on polyacrylamide gels. Biotin-epsilon-aminocaproic acid N-hydroxysuccinimide ester (BNHS) or N-biotinoyl-N'-(maleimidohexanoyl)hydrazine (BM) were the derivatizing agents. Only 10-12 bands were adsorbed onto streptavidin-agarose from undervatized cells or from derivatized cells treated with free avidin at 4 degrees C. Two-dimensional isoelectric focusing-sodium dodecyl sulfate gel electrophoresis resolved greater than 100 BNHS-derivatized proteins and greater than 40 BM-derivatized proteins. There appeared to be little overlap between the two groups of derivatized proteins. Short-term pulse-chase studies showed an accumulation of label into both groups of biotinylated proteins up until 1-2 h of chase and a rapid decrease over the next 1-5 h. Delayed appearance of labeled protein at the cell surface was attributed to transit time from site of synthesis. The unexpected and unexplained rapid disappearance of pulse-labeled proteins from the cell surface was invariant for all two-dimensionally resolved proteins and was sensitive to temperature reduction to 18 degrees C. Long-term pulse-chase experiments beginning 4-8 h after the initiation of chase showed the disappearance of derivatized proteins to be a simple first-order process having a half-life of 115 h in the case of BNHS-derivatized proteins and 30 h in the case of BM-derivatized proteins

Interactions between dodecyl phosphates and hydroxyapatite or tooth enamel: relevance to inhibition of dental erosion.

Science.gov (United States)

Jones, Siân B; Barbour, Michele E; Shellis, R Peter; Rees, Gareth D

2014-05-01

Tooth surface modification is a potential method of preventing dental erosion, a form of excessive tooth wear facilitated by softening of tooth surfaces through the direct action of acids, mainly of dietary origin. We have previously shown that dodecyl phosphates (DPs) effectively inhibit dissolution of native surfaces of hydroxyapatite (the type mineral for dental enamel) and show good substantivity. However, adsorbed saliva also inhibits dissolution and DPs did not augment this effect, which suggests that DPs and saliva interact at the hydroxyapatite surface. In the present study the adsorption and desorption of potassium and sodium dodecyl phosphates or sodium dodecyl sulphate (SDS) to hydroxyapatite and human tooth enamel powder, both native and pre-treated with saliva, were studied by high performance liquid chromatography-mass Spectrometry. Thermo gravimetric analysis was used to analyse residual saliva and surfactant on the substrates. Both DPs showed a higher affinity than SDS for both hydroxyapatite and enamel, and little DP was desorbed by washing with water. SDS was readily desorbed from hydroxyapatite, suggesting that the phosphate head group is essential for strong binding to this substrate. However, SDS was not desorbed from enamel, so that this substrate has surface properties different from those of hydroxyapatite. The presence of a salivary coating had little or no effect on adsorption of the DPs, but treatment with DPs partly desorbed saliva; this could account for the failure of DPs to increase the dissolution inhibition due to adsorbed saliva. Copyright © 2014 Elsevier B.V. All rights reserved.

Novel platelet-agglutinating protein from a thrombotic thrombocytopenic purpura plasma.

OpenAIRE

Siddiqui, F A; Lian, E C

1985-01-01

A novel platelet-agglutinating protein (PAP) was purified approximately 2,000-fold from the plasma of a patient with thrombotic thrombocytopenic purpura (TTP) by ammonium sulfate fractionation, DEAE-Sephacel and concanavalin A-Sepharose chromatographies. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with and without reduction, this preparation revealed a major protein band with a molecular weight of 37,000, and a minor band with a molecular weight of 32,000-34,000. After eluti...

High-resolution gel electrophoresis and sodium dodecyl sulphate-agarose gel electrophoresis on urine samples for qualitative analysis of proteinuria in dogs.

Science.gov (United States)

Giori, Luca; Tricomi, Flavia Marcella; Zatelli, Andrea; Roura, Xavier; Paltrinieri, Saverio

2011-07-01

The aims of the current study were to assess whether sodium dodecyl sulphate-agarose gel electrophoresis (SDS-AGE) and high-resolution electrophoresis (HRE) can identify dogs with a urinary protein-to-creatinine ratio (UPC ratio) >0.2 and whether HRE can provide preliminary information about the type of proteinuria, using SDS-AGE as a reference method. HRE and SDS-AGE were conducted on 87 urine samples classified according to the International Renal Interest Society as non-proteinuric (NP; UPC ratio: 0.51; 40/87). SDS-AGE and HRE were positive in 14 out of 32 and 3 out of 32 NP samples and in 52 out of 55 and 40 out of 55 samples with a UPC ratio >0.20, respectively. The concordance between HRE or SDS and UPC ratio was comparable (κ = 0.59; κ = 0.55). However, specificity (90%) and positive likelihood ratio (7.76) were higher for HRE than for SDS-AGE (56% and 2.16) while sensitivity was lower (73% vs. 94%). The analysis of HRE results revealed that a percentage of albumin >41.4% and an albumin/α(1)-globulin ratio (alb/α(1) ratio) >1.46 can identify samples classified by SDS-AGE as affected by glomerular proteinuria while a percentage of α(1)-globulin >40.8% and an alb/α(1) ratio HRE could misclassify samples with a UPC ratio higher or lower than 0.20. Therefore, UPC ratio must always be determined before conducting these tests. The percentage of albumin and α(1)-globulin or the alb/α(1) ratio determined by HRE can provide preliminary information about the origin of proteinuria.

Interaction of sodium dodecyl sulfate with watermelon chromoplasts and examination of the organization of lycopene within the chromoplasts.

Science.gov (United States)

Fish, Wayne W

2006-10-18

The properties of plant-derived precipitates of watermelon lycopene were examined in aqueous sodium dodecyl sulfate (SDS) as part of an ongoing effort to develop simpler, more economical ways to quantify carotenoids in melon fruit. Levels of SDS >0.2% were found to increase the water solubility of lycopene in the state in which it was isolated from watermelon. Electron microscopy and chemical analyses suggested that the watermelon lycopene as isolated is packaged inside a membrane to form a chromoplast. Spectral peaks in the visible region of the watermelon chromoplasts in SDS exhibited a bathochromic shift from those in organic solvent. Watermelon chromoplasts in SDS exhibited pronounced circular dichroic activity in the visible region. Binding measurements indicated that about 120 molecules of SDS were bound per molecule of lycopene inside the chromoplast; likely, the detergent molecules are bound to the chromoplast membrane. Around 80% of the chromoplast-SDS complexes were retained on a 0.45 mum membrane filter. Together, these observations are consistent with lycopene in a J-type chiral arrangement inside a membrane to form a chromoplast. The binding of SDS molecules to the chromoplast membrane form a complex that is extensively more water-soluble than the chromoplast alone.

Release mechanism of doxazosin from carrageenan matrix tablets: Effect of ionic strength and addition of sodium dodecyl sulphate.

Science.gov (United States)

Kos, Petra; Pavli, Matej; Baumgartner, Saša; Kogej, Ksenija

2017-08-30

The polyelectrolyte matrix tablets loaded with an oppositely charged drug exhibit complex drug-release mechanisms. In this study, the release mechanism of a cationic drug doxazosin mesylate (DM) from matrix tablets based on an anionic polyelectrolyte λ-carrageenan (λ-CARR) is investigated. The drug release rates from λ-CARR matrices are correlated with binding results based on potentiometric measurements using the DM ion-sensitive membrane electrode and with molecular characteristics of the DM-λ-CARR-complex particles through hydrodynamic size measurements. Experiments are performed in solutions with different ionic strength and with the addition of an anionic surfactant sodium dodecyl sulphate (SDS). It is demonstrated that in addition to swelling and erosion of tablets, the release rates depend strongly on cooperative interactions between DM and λ-CARR. Addition of SDS at concentrations below its critical micelle concentration (CMC) slows down the DM release through hydrophobic binding of SDS to the DM-λ-CARR complex. On the contrary, at concentrations above the CMC SDS pulls DM from the complex by forming mixed micelles with it and thus accelerates the release. Results involving SDS show that the concentration of surfactants that are naturally present in gastrointestinal environment may have a great impact on the drug release process. Copyright © 2017 Elsevier B.V. All rights reserved.

Hexavalent Molybdenum Reduction to Mo-Blue by a Sodium-Dodecyl-Sulfate-Degrading Klebsiella oxytoca Strain DRY14

Directory of Open Access Journals (Sweden)

M. I. E. Halmi

2013-01-01

Full Text Available Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS- degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v, between 25 and 30 mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5 mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition of the molybdenum-reducing activity, respectively. Ferrous and stannous ions markedly increased the activity of molybdenum-reducing activity in this bacterium. The maximum tolerable concentration of SDS as a cocontaminant was 3 g/L. The characteristics of this bacterium make it a suitable candidate for molybdenum bioremediation of sites cocontaminated with detergent pollutant.

Adsorption of hydroxamate siderophores and EDTA on goethite in the presence of the surfactant sodium dodecyl sulfate

Directory of Open Access Journals (Sweden)

Xu Jide

2009-06-01

Full Text Available Abstract Siderophore-promoted iron acquisition by microorganisms usually occurs in the presence of other organic molecules, including biosurfactants. We have investigated the influence of the anionic surfactant sodium dodecyl sulfate (SDS on the adsorption of the siderophores DFOB (cationic and DFOD (neutral and the ligand EDTA (anionic onto goethite (α-FeOOH at pH 6. We also studied the adsorption of the corresponding 1:1 Fe(III-ligand complexes, which are products of the dissolution process. Adsorption of the two free siderophores increased in a similar fashion with increasing SDS concentration, despite their difference in molecule charge. In contrast, SDS had little effect on the adsorption of EDTA. Adsorption of the Fe-DFOB and Fe-DFOD complexes also increased with increasing SDS concentrations, while adsorption of Fe-EDTA decreased. Our results suggest that hydrophobic interactions between adsorbed surfactants and siderophores are more important than electrostatic interactions. However, for strongly hydrophilic molecules, such as EDTA and its iron complex, the influence of SDS on their adsorption seems to depend on their tendency to form inner-sphere or outer-sphere surface complexes. Our results demonstrate that surfactants have a strong influence on the adsorption of siderophores to Fe oxides, which has important implications for siderophore-promoted dissolution of iron oxides and biological iron acquisition.

Conductometric study of sodium dodecyl sulfate - nonionic surfactant (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85 mixed micelles in aqueous solution

Directory of Open Access Journals (Sweden)

Ćirin Dejan M.

2012-01-01

Full Text Available The present study is concerned with the determination of the critical micelle concentration (cmc of mixed micelles of sodium dodecyl sulfate with one of five nonionic surfactants (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85 from conductance measurements. Based on the calculated values of the β parameters we have noticed that SDS-nonionic surfactants mostly showed strong synergistic effect. It was found that nonionic surfactants with mainly longer and more hydrophobic tail show stronger interactions with hydrophobic part of SDS, thus expressing stronger synergism. In SDS-Tween 80 binary system the strongest synergistic effect was noticed. SDS-Tween 85 micellar system showed antagonistic effect, most probably because the presence of the double bond in its three hydrophobic tails (three C18 tails makes it sterically rigid.

P-aminobenzoic acid and tritiated cyanoborohydride for the detection of pyruvoyl residues in proteins

International Nuclear Information System (INIS)

van Poelje, P.D.; Snell, E.E.

1987-01-01

A procedure for the detection of covalently bound pyruvic acid in purified proteins or in crude extracts is described. The dialyzed sample is first treated with sodium cyanoborohydride to reduce any Schiff bases present and then incubated with p-aminobenzoic acid and sodium [ 3 H]cyanoborohydride. Derivatized proteins are visualized by fluorography following sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Gel slices containing the labeled proteins are hydrolyzed, and, after removal of polyacrylic acid, the hydrolysate is subjected to ion-exchange high-performance liquid chromatography. The presence of pyruvic acid is established by the detection of a tritiated, 280-nm absorbing compound with a retention time corresponding to that of synthetic N-(p-carboxyphenyl)alanine. The procedure is capable of detecting protein-bound pyruvic acid in the picomolar range and is easily modified to screen for other covalently bound keto acids

An extensive characterization study of different Bacillus thuringiensis ...

African Journals Online (AJOL)

A comparative study between sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis and DNA hybridization was performed on 25 chosen different strains of B. ... The crystal proteins were quantified and then separated using sodium dodecyl sulphate-polyacrylamide gel electrophresis (SDS-PAGE).

Small angle neutron scattering studies of mixed micelles of sodium

Indian Academy of Sciences (India)

The aqueous solutions of sodium cumene sulphonate (NaCS) and its mixtures with each of cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) are characterized by small angle neutron scattering (SANS). NaCS when added to CTAB solution leads to the formation of long rod-shaped micelles with ...

Stress responses of duckweed (Lemna minor L.) and water velvet (Azolla filiculoides Lam.) to anionic surfactant sodium-dodecyl-sulphate (SDS).

Science.gov (United States)

Forni, C; Braglia, R; Harren, F J M; Cristescu, S M

2012-04-01

Surfactants are used for several purposes and recently they have attracted the attention for their ability to modify the behavior of other preexistent or co-disposed contaminants, although their use or discharge in wastewaters can represent a real or potential risk for the environment. Lemna minor L. and Azolla filiculoides Lam. are floating aquatic macrophytes, very effective in accumulating several pollutants including sodium dodecyl sulphate (SDS). In this work we evaluated the effects of SDS on these species by determining the stress ethylene production via laser-based trace gas detection, and the activities of enzymes involved in stress response, such as guaiacol peroxidase (G-POD), phenylalanine ammonia-lyase (PAL) and polyphenol-oxidase (PPO). Phenolics content was also determined. The macrophytes were treated with different concentrations of SDS for one week. SDS affected duckweed enzymatic activities and phenol content. While in the fern phenolics amount, PAL, G-POD and PPO activities were not affected by SDS except for 100 ppm SDS, the only concentration that was taken up and not completely degraded. Stress ethylene production was induced only in the fern treated with 50 and 100 ppm SDS. Copyright © 2011 Elsevier B.V. All rights reserved.

Restraining Na-Montmorillonite Delamination in Water by Adsorption of Sodium Dodecyl Sulfate or Octadecyl Trimethyl Ammonium Chloride on the Edges

Directory of Open Access Journals (Sweden)

Hongliang Li

2016-08-01

Full Text Available The delamination of montmorillonite in water leads to sliming in ore slurry, which is detrimental to mineral flotation and solid/water separation. In this work, the delamination of Na-montmorillonite (Na-MMT has been restrained by sodium dodecyl sulfate (SDS or octadecyl trimethyl ammonium chloride (1831 through the adsorption on the edge of the mineral. The experimental results have shown that the pretreatment by adding SDS and 1831 could greatly reduce the Stokes size percentage of −1.1 µm particles in the aqueous Na-MMT suspension. From the X-ray diffractometer (XRD results, the interlayer spacing of the MMT pre-treated by SDS and 1831 is smaller than that of original MMT particles. Adsorption position of SDS and 1831 on MMT surfaces was analyzed by the measurements of adsorption capacity of SDS and 1831, inductively-coupled plasma spectra, and zeta potential before and after the plane surface of MMT was covered with tetraethylenepentaminecopper ([Cu(tetren]2+. The results indicated that SDS and 1831 are adsorbed on the edge and the whole surface of Na-MMT, respectively. Delamination of MMT could be well restrained by the adsorption of SDS and 1831 on the edges of MMT.

Structural and phase transition changes of sodium dodecyl sulfate micellar solution in alcohols probed by small-angle neutron scattering (SANS)

Energy Technology Data Exchange (ETDEWEB)

Putra, Edy Giri Rachman [Neutron Scattering Laboratory, National Nuclear Energy Agency of Indonesia (BATAN), Gedung 40 BATAN, Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia); Patriati, Arum [Neutron Scattering Laboratory, National Nuclear Energy Agency of Indonesia (BATAN), Gedung 40 BATAN, Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia); Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Gadjah Mada, Bulaksumur, Yogyakarta 55281, Indonesia giri@batan.go.id (Indonesia)

2015-04-16

Small-angle neutron scattering (SANS) measurements on 0.3M sodium dodecyl sulfate (SDS) micellar solutions have been performed in the presence of n-alcohols, from ethanol to decanol at different alcohol concentrations, 2–10 wt%. The ellipsoid micellar structure which occurred in the 0.3M SDS in aqueous solution with the size range of 30–50 Å has different behavior at various hydrocarbon chain length and concentration of alcohols. At low concentration and short chain-length of alcohols, such as ethanol, propanol, and butanol, the size of micelles reduced and had a spherical-like structure. The opposite effect occurred as medium to long chain alcohols, such as hexanol, octanol and decanol was added into the 0.3M SDS micellar solutions. The micelles structure changed to be more elongated in major axis and then crossed the critical phase transition from micellar solution into liquid crystal phase as lamellar structure emerged by further addition of alcohols. The inter-lamellar distances were also depending on the hydrocarbon chain length and concentration of alcohols. In the meantime, the persistent micellar structures occurred in addition of medium chain of n-alcohol, pentanol at all concentrations.

Structural and phase transition changes of sodium dodecyl sulfate micellar solution in alcohols probed by small-angle neutron scattering (SANS)

International Nuclear Information System (INIS)

Putra, Edy Giri Rachman; Patriati, Arum

2015-01-01

Small-angle neutron scattering (SANS) measurements on 0.3M sodium dodecyl sulfate (SDS) micellar solutions have been performed in the presence of n-alcohols, from ethanol to decanol at different alcohol concentrations, 2–10 wt%. The ellipsoid micellar structure which occurred in the 0.3M SDS in aqueous solution with the size range of 30–50 Å has different behavior at various hydrocarbon chain length and concentration of alcohols. At low concentration and short chain-length of alcohols, such as ethanol, propanol, and butanol, the size of micelles reduced and had a spherical-like structure. The opposite effect occurred as medium to long chain alcohols, such as hexanol, octanol and decanol was added into the 0.3M SDS micellar solutions. The micelles structure changed to be more elongated in major axis and then crossed the critical phase transition from micellar solution into liquid crystal phase as lamellar structure emerged by further addition of alcohols. The inter-lamellar distances were also depending on the hydrocarbon chain length and concentration of alcohols. In the meantime, the persistent micellar structures occurred in addition of medium chain of n-alcohol, pentanol at all concentrations

Alkylresorcinols in rye (Secale cereale L. caryopses. III. Application of detergents for extraction of proteins and alkylresorcinols

Directory of Open Access Journals (Sweden)

W. Mejbaum-Katzenellenbogen

2015-01-01

Full Text Available In the work here described sodium dodecyl sulphate solutions (SDS, tween 80 and triton X 100 were used for isolation of proteins and 5-n-alkylresorcinols from ground rye grain. It was found that the above named detergents extract different protein and various amounts of alkylresorcin derivatives. The results indicate that 5-n-alkylresorcinols are localized in the membraneous structures of rye caryopses.

Analysis on Protein Profile and Amino Acid of Edible Bird's Nest (Collocalia Fuchiphaga) From Painan

OpenAIRE

Elfita, Lina

2014-01-01

This study was aimed to analyze protein profile and amino acid composition of bird nest from Painan, Pesisir Selatan Distric, West Sumatra. Protein analysis was performed by Sodium Dodecyl Sulphate Polyacrilamide Gel Electrophoresis (SDS-PAGE), meanwhile High Performance Liquid Chromatography (HPLC) was used for analysis of amino acid. Analysis on water extract of bird nest by SDS-PAGE showed six bands which correspond to molecular protein which had molecular weight of 147.2; 142.6; 133.4; 73...

Impact of model perfume molecules on the self-assembly of anionic surfactant sodium dodecyl 6-benzene sulfonate.

Science.gov (United States)

Bradbury, Robert; Penfold, Jeffrey; Thomas, Robert K; Tucker, Ian M; Petkov, Jordan T; Jones, Craig; Grillo, Isabelle

2013-03-12

The impact of two model perfumes with differing degrees of hydrophobicity/hydrophilicity, linalool (LL) and phenylethanol (PE), on the solution structure of anionic surfactant sodium dodecyl 6-benzene sulfonate, LAS-6, has been studied by small angle neutron scattering, SANS. For both types of perfume molecules, complex phase behavior is observed. The phase behavior depends upon the concentration, surfactant/perfume composition, and type of perfume. The more hydrophilic perfume PE promotes the formation of more highly curved structures. At relatively low surfactant concentrations, small globular micelles, L1, are formed. These become perfume droplets, L(sm), stabilized by the surfactant at much higher perfume solution compositions. At higher surfactant concentrations, the tendency of LAS-6 to form more planar structures is evident. The more hydrophobic linalool promotes the formation of more planar structures. Combined with the greater tendency of LAS-6 to form planar structures, this results in the planar structures dominating the phase behavior for the LAS-6/linalool mixtures. For the LAS-6/linalool mixture, the self-assembly is in the form of micelles only at the lowest surfactant and perfume concentrations. Over most of the concentration-composition space explored, the structures are predominantly lamellar, L(α), or vesicle, L(v), or in the form of a lamellar/micellar coexistence. At low and intermediate amounts of LL, a significantly different structure is observed, and the aggregates are in the form of small, relatively monodisperse vesicles (i.e., nanovesicles), L(sv).

Sodium dodecyl sulfate-assisted hydrothermal synthesis of mesoporous nickel cobaltite nanoparticles with enhanced catalytic activity for methanol electrooxidation

Science.gov (United States)

Ding, Rui; Qi, Li; Jia, Mingjun; Wang, Hongyu

2014-04-01

Mesoporous nickel cobaltite (NiCo2O4) nanoparticles have been synthesized via a facile hydrothermal strategy with the assistance of sodium dodecyl sulfate (SDS) soft template (ST). Their physicochemical properties have been characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectra (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. Their electrocatalytic performances have been examined by cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) tests. The obtained NiCo2O4 materials exhibit a typical nanoscale crystalline hexagonal morphology with specific surface area (SSA) and mesopore volume of 88.63 m2 g-1 and 0.298 cm3 g-1. Impressively, the SDS-assisted NiCo2O4 electrode shows a catalytic current density of 125 mA cm-2 and 72% retention for consecutive 1000 s at 0.6 V in 1 M KOH and 0.5 M CH3OH electrolytes towards methanol (CH3OH) electrooxidation, which is better than the one without SDS assistance. The pronounced electrocatalytic activity is largely ascribed to their higher surface intensities of Co and Ni species and superior mesoporous nanostructures, which provide the richer electroactive sites and faster electrochemical kinetics, leading to the enhanced electrocatalytic activity.

Molecular mechanism of catalase activity change under sodium dodecyl sulfate-induced oxidative stress in the mouse primary hepatocytes.

Science.gov (United States)

Wang, Jing; Wang, Jiaxi; Xu, Chi; Liu, Rutao; Chen, Yadong

2016-04-15

Sodium dodecyl sulfate (SDS) contributes to adverse effects of organisms probably because of its ability to induce oxidative stress via changing the activity of antioxidant enzyme catalase (CAT). But the underlying molecular mechanisms still remain unclear. This study characterized the harmful effects of SDS-induced oxidative stress on the mouse primary hepatocytes as well as the structure and function of CAT molecule and investigated the underlying molecular mechanism. After 12h SDS (0.1μM to 0.2mM) exposure, no significant change was observed in CAT activity of the hepatocytes. After 0.5 and 0.8mM SDS exposure, the state of oxidative stress stimulated CAT production in the hepatocytes. The inhibition of CAT activity induced by directly interacting with SDS was unable to catch the synthesis of CAT and therefore resulted in the increased activity and elevated ROS level. Further molecular experiments showed that SDS prefers to bind to the interface with no direct effect on the active site and the structure of heme groups of CAT molecule. When the sites in the interface is saturated, SDS interacts with VAL 73, HIS 74, ASN 147 and PHE 152, the key residues of the enzyme activity, and leads to the decrease of CAT activity. Copyright © 2015 Elsevier B.V. All rights reserved.

Cell Wall-Associated Protein Antigens of Streptococcus salivarius: Purification, Properties, and Function in Adherence

OpenAIRE

Weerkamp, Anton H.; Jacobs, Ton

1982-01-01

Three cell wall-associated protein antigens (antigens b, c, and d) were isolated from mutanolysin-solubilized cell walls of Streptococcus salivarius HB and purified to apparent homogeneity by a combination of ion-exchange chromatography, gel filtration, and immunoadsorption chromatography. Antigens b and c were also isolated from culture supernatants. Antigen b consisted of more than 80% protein and had an apparent molecular weight as determined by sodium dodecyl sulfate-polyacrylamide gel el...

Prolactin-inducible proteins in human breast cancer cells

International Nuclear Information System (INIS)

Shiu, R.P.; Iwasiow, B.M.

1985-01-01

The mechanism of action of prolactin in target cells and the role of prolactin in human breast cancer are poorly understood phenomena. The present study examines the effect of human prolactin (hPRL) on the synthesis of unique proteins by a human breast cancer cell line, T-47D, in serum-free medium containing bovine serum albumin. [ 35 S]Methionine-labeled proteins were analysed by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis and fluorography. Treatment of cells with hPRL (1-1000 ng/ml) and hydrocortisone (1 microgram/ml) for 36 h or longer resulted in the synthesis and secretion of three proteins having molecular weights of 11,000, 14,000, and 16,000. Neither hPRL nor hydrocortisone alone induced these proteins. Of several other peptide hormones tested, only human growth hormone, a hormone structurally and functionally similar to hPRL, could replace hPRL in causing protein induction. These three proteins were, therefore, referred to as prolactin-inducible proteins (PIP). Each of the three PIPs was purified to homogeneity by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and specific antibodies were generated to them in rabbits. By immunoprecipitation and immunoblotting (Western blot) of proteins secreted by T-47D cells, it was demonstrated that the three PIPs were immunologically identical to one another. In addition, the 16-kDa and 14-kDa proteins (PIP-16 and PIP-14), and not the 11-kDa protein (PIP-11), incorporated [ 3 H]glycosamine. Furthermore, 2-deoxyglucose (2 mM) and tunicamycin (0.5 micrograms/ml), two compounds known to inhibit glycosylation, blocked the production of PIP-16 and PIP-14, with a concomitant increase in the accumulation of PIP-11

Influence of sodium dodecyl sulfonate (SDS) on the hydrothermal synthesis of YVO4:Eu3+ crystals in a wide pH range

International Nuclear Information System (INIS)

Wang Juan; Xu Yunhua; Hojamberdiev, Mirabbos; Zhu Gangqiang

2009-01-01

In this work, a facile hydrothermal route has been proposed for the morphology-controllable preparation of Eu-doped yttrium orthovanadate (YVO 4 :Eu 3+ ) powders in the presence of sodium dodecyl sulfonate (SDS) as a template in a wide pH range. The structure, composition, morphology, and optical properties of the final products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence spectroscopy (PL), respectively. It was found that single phase YVO 4 :Eu 3+ micro- and nanocrystals with different shapes can be fabricated at 180 deg. C for 24 h with suitable amount of SDS in a wide pH range. The formation mechanism and the influence of SDS on the morphology of YVO 4 :Eu 3+ micro- and nanocrystals were investigated as a function of pH value. The PL measurement revealed that the samples with different morphologies exhibited different values for optical properties, especially soybean-like nanopowders showed a higher intensity compared to other samples with different morphologies due mainly to their high packing densities and low scattering of light.

Purification and identification of the fusicoccin binding protein from oat root plasma membrane

Science.gov (United States)

de Boer, A. H.; Watson, B. A.; Cleland, R. E.

1989-01-01

Fusicoccin (FC), a fungal phytotoxin, stimulates the H(+) -ATPase located in the plasma membrane (PM) of higher plants. The first event in the reaction chain leading to enhanced H(+) -efflux seems to be the binding of FC to a FC-binding protein (FCBP) in the PM. We solubilized 90% of the FCBP from oat (Avena sativa L. cv Victory) root PM in an active form with 1% octyl-glucoside. The FCBP was stabilized by the presence of protease inhibitors. The FCBP was purified by affinity chromatography using FC-linked adipic acid dihydrazide agarose (FC-AADA). Upon elution with 8 molar urea, two major protein bands on sodium dodecyl sulfate-polyaerylamide gel electrophoresis with molecular weights of 29,700 and 31,000 were obtained. Successive chromatography on BBAB Bio-Gel A, hexyl agarose, and FC-AADA resulted in the same two bands when the FC-AADA was eluted with sodium dodecyl sulfate. A direct correlation was made between 3H-FC-binding activity and the presence of the two protein bands. The stoichiometry of the 29,700 and 31,000 molecular weight bands was 1:2. This suggests that the FCBP occurs in the native form as a heterotrimer with an apparent molecular weight of approximately 92,000.

Flame atomic absorption spectrometric determination of trace amounts of heavy metal ions after solid phase extraction using modified sodium dodecyl sulfate coated on alumina

Energy Technology Data Exchange (ETDEWEB)

Ghaedi, Mehrorang [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of)], E-mail: m_ghaedi@mail.yu.ac.ir; Niknam, Khodabakhsh [Chemistry Department, Persian Gulf University, Bushehr (Iran, Islamic Republic of); Shokrollahi, Ardeshir; Niknam, Ebrahim; Rajabi, Hamid Reza [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, Mustafa [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

2008-06-30

A sensitive and selective solid phase extraction procedure for the determination of traces of Cu(II), Zn(II), Pb(II) and Fe(III) has been developed. An alumina-sodium dodecyl sulfate (SDS) coated on with meso-phenyl bis(indolyl) methane (MPBIM) was used for preconcentration and determination of Cu(II), Zn(II), Pb(II) and Fe(III) ions by flame atomic absorption spectrometry. The analyte ions were adsorbed quantitatively on adsorbent due to their complexation with MPBIM. Adsorbed metals were quantitatively eluted using 6 mL of 4 mol L{sup -1} nitric acid. The effects of parameters such as pH, amount of alumina, amount of MBITP, flow rate, type and concentration of eluting agent were examined. The effects of interfering ions on the separation-preconcentration of analytes were also investigated. The relative standard deviation of the method was found to be less than 3.0%. The presented procedure was successfully applied for determination of analytes in real samples.

One-step enrichment and chemiluminescence detection of sodium dodecyl benzene sulfonate in river water using Mg-Al-carbonate layered double hydroxides.

Science.gov (United States)

Guan, Weijiang; Zhou, Wenjuan; Han, Dongmei; Zhang, Mengchun; Lu, Chao; Lin, Jin-Ming

2014-03-01

In this work, Mg-Al CO3-layered double hydroxides (LDHs) were used as adsorbent materials for sodium dodecyl benzene sulfonate (SDBS) in aqueous solutions, the enriched SDBS can be directly detected by IO4(-)-H2O2 chemiluminescence (CL) system. The commonly existing cations cannot be enriched by Mg-Al CO3-LDHs due to the structurally positively charged layers of LDHs, while other adsorbed anionic interferents had no effect on the IO4(-)-H2O2 CL reaction. The corresponding linear regression equation was established in the range of 0.1-10 μM for SDBS. The detection limit at a signal-to-noise (S/N) ratio of 3 for SDBS was 0.08 μM. The relative standard deviation (RSD) for nine repeated measurements of 0.5 μM SDBS was 2.6%. This proposed method has been successfully applied to the determination of SDBS in river water samples. To the best of our knowledge, we have first time coupled the high enrichment capacity of LDHs towards anions with CL detection for analytes. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of Glu-B3 Allelic Variation on Sodium Dodecyl Sulfate Sedimentation Volume in Common Wheat (Triticum aestivum L.

Directory of Open Access Journals (Sweden)

Hongqi Si

2013-01-01

Full Text Available Sodium dodecyl sulfate (SDS sedimentation volume has long been used to characterize wheat flours and meals with the aim of predicting processing and end-product qualities. In order to survey the influence of low-molecular-weight glutenin subunits (LMW-GSs at Glu-B3 locus on wheat SDS sedimentation volume, a total of 283 wheat (Triticum aestivum L. varieties including landraces and improved and introduced cultivars were analyzed using 10 allele-specific PCR markers at the Glu-B3 locus. The highest allele frequency observed in the tested varieties was Glu-B3i with 21.9% in all varieties, 21.1% in landraces, 25.5% in improved cultivars, and 12% in introduced cultivars. Glu-B3 locus represented 8.6% of the variance in wheat SDS sedimentation volume, and Glu-B3b, Glu-B3g, and Glu-B3h significantly heightened the SDS sedimentation volume, but Glu-B3a, Glu-B3c, and Glu-B3j significantly lowered the SDS sedimentation volume. For the bread-making quality, the most desirable alleles Glu-B3b and Glu-B3g become more and more popular and the least desirable alleles Glu-B3a and Glu-B3c got less and less in modern improved cultivars, suggesting that wheat grain quality in China has been significantly improved through breeding effort.

Interactions of glutamine dipeptides with sodium dodecyl sulfate in aqueous solution measured by volume, conductivity, and fluorescence spectra

Energy Technology Data Exchange (ETDEWEB)

Yan Zhenning, E-mail: yanzzn@zzu.edu.cn [Department of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001 (China); Sun Ximeng; Li Weiwei; Li Yu [Department of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001 (China); Wang Jianji [Department of Chemistry, Henan Normal University, Xinxiang, Henan 453007 (China)

2011-10-15

Highlights: > Ion-ion and ion-polar group interactions are dominant interactions. > The SDS addition and temperature increase cause a dehydration effect on dipeptides. > The addition of dipeptide in water decreases the c{sub cmc} of SDS. > Enthalpy-entropy compensation takes place during micellization. > Micelle aggregation number was decreased by addition of glutamine dipeptides. - Abstract: Densities, conductivities, and fluorescence spectra of {l_brace}sodium dodecyl sulfate (SDS) + glutamine dipeptide + water{r_brace} mixtures were measured as a function of temperature. The density data have been utilized to calculate apparent molar volumes, standard partial molar volumes (V{sub 2,{phi}}{sup o}), standard partial molar volumes of transfer from water to aqueous SDS solutions ({Delta}{sub t}V{sup o}), the hydration number, partial molar expansibility (E{sub {phi}}{sup o}), and Hepler's constant of glutamine dipeptides. The critical micellar concentration (c{sub cmc}) and the degree of counterion dissociation of SDS micelles obtained from electrical conductivity data have been estimated at various concentrations of glutamine dipeptide. Thermodynamic parameters of micellization of SDS in aqueous dipeptide solutions have been determined from c{sub cmc} values and an enthalpy-entropy compensation effect was observed for the ternary systems. The pyrene fluorescence spectra were used to study the change of micropolarity produced by the interaction of SDS with glutamine dipeptide, and the aggregation behavior of SDS. The results have been interpreted in terms of solute-solvent interactions and structural changes in the mixed solutions.

Fluorescent Binary Ensemble Based on Pyrene Derivative and Sodium Dodecyl Sulfate Assemblies as a Chemical Tongue for Discriminating Metal Ions and Brand Water.

Science.gov (United States)

Zhang, Lijun; Huang, Xinyan; Cao, Yuan; Xin, Yunhong; Ding, Liping

2017-12-22

Enormous effort has been put to the detection and recognition of various heavy metal ions due to their involvement in serious environmental pollution and many major diseases. The present work has developed a single fluorescent sensor ensemble that can distinguish and identify a variety of heavy metal ions. A pyrene-based fluorophore (PB) containing a metal ion receptor group was specially designed and synthesized. Anionic surfactant sodium dodecyl sulfate (SDS) assemblies can effectively adjust its fluorescence behavior. The selected binary ensemble based on PB/SDS assemblies can exhibit multiple emission bands and provide wavelength-based cross-reactive responses to a series of metal ions to realize pattern recognition ability. The combination of surfactant assembly modulation and the receptor for metal ions empowers the present sensor ensemble with strong discrimination power, which could well differentiate 13 metal ions, including Cu 2+ , Co 2+ , Ni 2+ , Cr 3+ , Hg 2+ , Fe 3+ , Zn 2+ , Cd 2+ , Al 3+ , Pb 2+ , Ca 2+ , Mg 2+ , and Ba 2+ . Moreover, this single sensing ensemble could be further applied for identifying different brands of drinking water.

Protein profiles of field isolates ofBacillus anthracis from different endemic areas of Indonesia

Directory of Open Access Journals (Sweden)

M Bhakti Poerwadikarta

1998-03-01

Full Text Available Sonicated cell-free extract proteins of 14 field isolates ofBacillus anthracis from six different endemic areas of Indonesia were analyzed by the use of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE methods . The protein profiles of each field isolate tested demonstrated slightly different at the protein bands with molecular weights of 18, 37, 52, 65 and 70 kDa, and varied between the field isolates and vaccine strains. The variation could provide clues to the source of anthrax transmission whether it was originated from similar strain or not.

Decellularized Rat Lung Scaffolds Using Sodium Lauryl Ether Sulfate for Tissue Engineering.

Science.gov (United States)

Ma, Jinhui; Ju, Zhihai; Yu, Jie; Qiao, Yeru; Hou, Chenwei; Wang, Chen; Hei, Feilong

Perfusion decellularization with detergents is effective to maintain the architecture and proteins of extracellular matrix (ECM) for use in the field of lung tissue engineering (LTE). However, it is unclear which detergent is ideal to produce an acellular lung scaffold. In this study, we obtained two decellularized rat lung scaffolds using a novel detergent sodium lauryl ether sulfate (SLES) and a conventional detergent sodium dodecyl sulfate (SDS). Both decellularized lung scaffolds were assessed by histology, immunohistochemistry, scanning electron microscopy, DNA quantification, sulfated glycosaminoglycans (GAGs) quantification and western blot. Subsequently, the scaffolds were implanted subcutaneously in rats for 6 weeks and were evaluated via hematoxylin and eosin staining and Masson staining. Results indicated that SLES was effective to remove cells; moreover, lungs decellularized with SLES showed better preservation of sulfated GAGs, lung architecture, and ECM proteins than SDS. After 6 weeks, SLES scaffolds demonstrated a significantly greater potential for cell infiltration and blood vessel formation compared with SDS scaffolds. Taken together, we conclude that SLES is a promising detergent to produce an acellular scaffold using LTE for eventual transplantation.

Effects of copper and tributyltin on stress protein abundance in the rotifer Brachionus plicatilis.

Science.gov (United States)

Cochrane, B J; Irby, R B; Snell, T W

1991-01-01

1. Exposure of the rotifer Brachionus plicatilis to elevated temperature resulted in the synthesis of a number of proteins, including a prominent one of 58,000 Da (SP58). 2. This protein is immunologically crossreactive with the 65,000 Da heat shock protein of the moth Heliothis virescens, which is a member of a highly conserved family of mitochondrial proteins. 3. Exposure of rotifers to sublethal doses of CuSO4 leads to a 4-5-fold increase in abundance of SP58, with maximum increase occurring at a dose that is approximately 5% of the LC50 for that compound. 4. A similar response was seen with tributyl tin (TBT). Kinetics of induction were sigmoidal, with induction occurring in the range of 20-30 micrograms/l. 5. No response was observed when rotifers were exposed to aluminum chloride, mercury chloride, pentachlorophenol, sodium arsenite, sodium azide, sodium dodecyl sulfate, or zinc chloride. 6. These results indicate that changes in stress protein abundance may prove useful as a biomarker of exposure to particular toxicants.

Functional Assessment of Skeletal Muscle Regeneration Utilizing Homologous Extracellular Matrix as Scaffolding

Science.gov (United States)

2010-01-01

Friedberg, T., and Oesch, F. Colorimetric quan- titation of trace amounts of sodium lauryl sulfate in the presence of nucleic acids and proteins. Anal Biochem...size. The muscle was rinsed with water and submerged in 2% sodium dodecyl sulfate (SDS) and agitated continuously. The SDS solution was changed twice...1. (A) Coomassie staining of sodium dodecyl sulfate –polyacrylamide gel electrophoresis gel. (B) Visual appearance of decellularized ECM. (C) Scanning

Usefulness of 8 kDa protein of Fasciola hepatica in diagnosis of fascioliasis

Science.gov (United States)

Kim, Kwangsig; Yang, Hyun Jong

2003-01-01

This study was designed to detect and evaluate an antigenicity of low molecular weight proteins of Fasciola hepatica in fascioliasis. Low molecular weight protein of F. hepatica was purified by ammonium sulfate precipitation and Sephacryl S-100 HR gel filtration. The protein obtained was estimated to be 8 kDa on 7.5-15% gradient sodium dodecyl sulfate gel electrophoresis. Immunoblotting studies showed that the 8 kDa protein reacted with human fascioliasis sera, but not other trematodiasis sera. This result suggests that the 8 kDa protein of F. hepatica is one of diagnostic antigens in human fascioliasis without cross-reaction with other human trematodiasis. PMID:12815325

Isolation and Characterization of Pseudomonas spp. Strains That Efficiently Decompose Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Ewa M. Furmanczyk

2017-11-01

Full Text Available Due to their particular properties, detergents are widely used in household cleaning products, cosmetics, pharmaceuticals, and in agriculture as adjuvants tailoring the features of pesticides or other crop protection agents. The continuously growing use of these various products means that water soluble detergents have become one of the most problematic groups of pollutants for the aquatic and terrestrial environments. Thus it is important to identify bacteria having the ability to survive in the presence of large quantities of detergent and efficiently decompose it to non-surface active compounds. In this study, we used peaty soil sampled from a surface flow constructed wetland in a wastewater treatment plant to isolate bacteria that degrade sodium dodecyl sulfate (SDS. We identified and initially characterized 36 Pseudomonas spp. strains that varied significantly in their ability to use SDS as their sole carbon source. Five isolates having the closest taxonomic relationship to the Pseudomonas jessenii subgroup appeared to be the most efficient SDS degraders, decomposing from 80 to 100% of the SDS present in an initial concentration 1 g/L in less than 24 h. These isolates exhibited significant differences in degree of SDS degradation, their resistance to high detergent concentration (ranging from 2.5 g/L up to 10 g/L or higher, and in chemotaxis toward SDS on a plate test. Mass spectrometry revealed several SDS degradation products, 1-dodecanol being dominant; however, traces of dodecanal, 2-dodecanol, and 3-dodecanol were also observed, but no dodecanoic acid. Native polyacrylamide gel electrophoresis zymography revealed that all of the selected isolates possessed alkylsulfatase-like activity. Three isolates, AP3_10, AP3_20, and AP3_22, showed a single band on native PAGE zymography, that could be the result of alkylsulfatase activity, whereas for isolates AP3_16 and AP3_19 two bands were observed. Moreover, the AP3_22 strain exhibited a band

Binding of sodium dodecyl sulfate with linear and branched polyethyleneimines in aqueous solution at different pH values.

Science.gov (United States)

Wang, Hao; Wang, Yilin; Yan, Haike; Zhang, Jin; Thomas, Robert K

2006-02-14

Isothermal titration microcalorimetry (ITC), conductivity, and turbidity measurements have been carried out to study the interaction of sodium dodecyl sulfate (SDS) with polyethyleneimines (PEI) including linear PEI and branched PEI at different pH values of 3, 7, and 10. In all cases, the polymers show a remarkable affinity toward SDS. At pH 3, the polymer PEI is a strong polycation, and the binding is dominated by electrostatic 1:1 charge neutralization with the anionic surfactant. At pH 7, the electrostatic attraction between SDS and PEI is weak, and the hydrophobic interaction becomes stronger. At the natural pH of 10, PEI is essentially nonionic and binds SDS in the form of polymer-bound surfactant aggregates. The charge neutralization concentration (C1) of SDS for the PEI-SDS complex can be derived from the curves of variation of the enthalpy, conductivity, and turbidity with SDS concentration. There is good agreement between the results from the three methods and all show a decrease with increasing pH. The total interaction enthalpies (deltaH(total)) of PEI with SDS are obtained from the observed enthalpy curves and the difference enthalpy (deltaH*) between the total enthalpy of branched PEI with SDS, and the total enthalpy of linear PEI with SDS can be derived from the obtained deltaH(total). The difference deltaH* increases dramatically as pH increases, which indicates that the interactions are different for linear PEI and branched PEI at high pH values. A schematic map of the different states of aggregation is presented.

Method for the typing of Clostridium difficile based on polyacrylamide gel electrophoresis of [35S]methionine-labeled proteins

International Nuclear Information System (INIS)

Tabaqchali, S.; O'Farrell, S.; Holland, D.; Silman, R.

1986-01-01

A typing method for Clostridium difficile based on the incorporation of [ 35 S]methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile

Genotoxic effects of 2-dodecyl cyclobutanone

International Nuclear Information System (INIS)

Delincee, H.; Pool-Zobel, B.L.; Rechkemmer, G.

1999-01-01

The paper reports in vivo experiments with rats who received two different doses of 2-dodecyl cyclobutane administered orally. 16 hours after administration, colon cells were isolated and examined for DNA damage by means of the comet assay. No cytotoxic effects were found with the trypan blue exclusion test. When the '% tail intensity' or the 'tail moment' were used for quantitative analysis with the comet assay, it was found that similar results are obtained for the test group which received a lower dose of 2-dodecyl cyclobutane (1.12 mg/kg of body weight) and the control group which received 2% dimethyl sulfoxide. Administration of higher concentrations of the 2-dodecyl cyclobutane (14.9 mg/kg of body weight) was found to induce minor, but significant DNA damage in the test group. Further experiments will be needed in order to assess the relevance of these results for assessment of health risks due to consumption of irradiated food. (orig./CB) [de

Response of rat brain protein synthesis to ethanol and sodium barbital

International Nuclear Information System (INIS)

Tewari, S.; Greenberg, S.A.; Do, K.; Grey, P.A.

1987-01-01

Central nervous system (CNS) depressants such as ethanol and barbiturates under acute or chronic conditions can induce changes in rat brain protein synthesis. While these data demonstrate the individual effects of drugs on protein synthesis, the response of brain protein synthesis to alcohol-drug interactions is not known. The goal of the present study was to determine the individual and combined effects of ethanol and sodium barbital on brain protein synthesis and gain an understanding of the mechanisms by which these alterations in protein synthesis are produced. Specifically, the in vivo and in vitro effects of sodium barbital (one class of barbiturates which is not metabolized by the hepatic tissue) were examined on brain protein synthesis in rats made physically dependent upon ethanol. Using cell free brain polysomal systems isolated from Control, Ethanol and 24 h Ethanol Withdrawn rats, data show that sodium barbital, when intubated intragastrically, inhibited the time dependent incorporation of 14 C) leucine into protein by all three groups of ribosomes. Under these conditions, the Ethanol Withdrawn group displayed the largest inhibition of the 14 C) leucine incorporation into protein when compared to the Control and Ethanol groups. In addition, sodium barbital when added at various concentrations in vitro to the incubation medium inhibited the incorporation of 14 C) leucine into protein by Control and Ethanol polysomes. The inhibitory effects were also obtained following preincubation of ribosomes in the presence of barbital but not cycloheximide. Data suggest that brain protein synthesis, specifically brain polysomes, through interaction with ethanol or barbital are involved in the functional development of tolerance. These interactions may occur through proteins or polypeptide chains or alterations in messenger RNA components associated with the ribosomal units

Method for the typing of Clostridium difficile based on polyacrylamide gel electrophoresis of (/sup 35/S)methionine-labeled proteins

Energy Technology Data Exchange (ETDEWEB)

Tabaqchali, S.; O' Farrell, S.; Holland, D.; Silman, R.

1986-01-01

A typing method for Clostridium difficile based on the incorporation of (/sup 35/S)methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile.

Voltammetric determination of sudan ii in food samples at graphene modified glassy carbon electrode based on the enhancement effect of sodium dodecyl sulfate

International Nuclear Information System (INIS)

Ma, X.; Chen, M.; Chao, M.

2013-01-01

Summary: Herein, a novel electrochemical method was de veloped for the determination of Sudan II based on the electrochemical catalytic activity of graphene modified glassy carbon electrode (GME) and the enhancement effect of sodium dodecyl sulfate (SDS). In a pH 6.0 phosphate buffer solution, Sudan II exhibited a pair of well-defined quasi reversible redox peaks at the GME in the presence of 5.0x10/sup -5/ mol L/sup 1/ SDS. The oxidation peak current of Sudan II was linearly proportional to its concentration in a range from 4.0x10/sup -8/ to 4.0x10/sup -6/ mol L/sup 1/, with a linear regression equation of ipa (A) = 3.35 c + 5.96 x 10/sup -6/, r = 0.9988 and a detection limit of 8.0x10/sup -9/ mol L/sup 1/. The recoveries from the standards fortified blank samples were in the range of 94.7% to 97.5% with RSD lower than 4.0%. The novel method has been successfully used to determine Sudan II in food products with satisfactory results. (author)

Conditions that allow for effective transfer of membrane proteins onto nitrocellulose membrane in Western blots.

Science.gov (United States)

Abeyrathne, Priyanka D; Lam, Joseph S

2007-04-01

A major hurdle in characterizing bacterial membrane proteins by Western blotting is the ineffectiveness of transferring these proteins from sodium dodecyl sulfate -- polyacrylamide gel electrophoresis (SDS-PAGE) gel onto nitrocellulose membrane, using standard Western blot buffers and electrophoretic conditions. In this study, we compared a number of modified Western blotting buffers and arrived at a composition designated as the SDS-PAGE-Urea Lysis buffer. The use of this buffer and specific conditions allowed the reproducible transfer of highly hydrophobic bacterial membrane proteins with 2-12 transmembrane-spanning segments as well as soluble proteins onto nitrocellulose membranes. This method should be broadly applicable for immunochemical studies of other membrane proteins.

Comparison of Yeast Cell Protein Solubilization Procedures for Two-dimensional Electrophoresis

DEFF Research Database (Denmark)

Harder, A; Wildgruber, R; Nawrocki, A

1999-01-01

Three different procedures for the solubilization of yeast (S. cerevisiae) cell proteins were compared on the basis of the obtained two-dimensional (2-D) polypeptide patterns. Major emphasis was laid on minimizing handling steps, protein modification or degradation, and quantitative loss of high...... with sodium dodecyl sulfate (SDS) buffer, consisting of 1% SDS and 100 mM tris(hydroxymethyl)aminomethane (Tris)-HCl, pH 7.0, followed by dilution with "standard" lysis buffer, and (iii) boiling the sample with SDS during cell lysis, followed by dilution with thiourea/urea lysis buffer (2 M thiourea/ 7 M urea...

Limited tryptic proteolysis of the benzodiazepine binding proteins in different species reveals structural homologies.

Science.gov (United States)

Friedl, W; Lentes, K U; Schmitz, E; Propping, P; Hebebrand, J

1988-12-01

Peptide mapping can be used to elucidate further the structural similarities of the benzodiazepine binding proteins in different vertebrate species. Crude synaptic membrane preparations were photoaffinity-labeled with [3H]flunitrazepam and subsequently degraded with various concentrations of trypsin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by fluorography allowed a comparison of the molecular weights of photolabeled peptides in different species. Tryptic degradation led to a common peptide of 40K in all species investigated, a finding indicating that the benzodiazepine binding proteins are structurally homologous in higher bony fishes and tetrapods.

Effect of γ-irradiation on the physicochemical properties and structure of fish myofibrillar proteins

Science.gov (United States)

Shi, Yan; Li, Ru-yi; Tu, Zong-cai; Ma, Da; Wang, Hui; Huang, Xiao-qin; He, Na

2015-04-01

The influence of γ-irradiation on physicochemical properties and structures of myofibrillar protein from grass crap exposed to dose up to 10 kGy was investigated. Irradiated samples exhibited decreased emulsifying property and increased surface hydrophobicity. Increasing dose resulted in decreasing free and total sulphydryl groups, decreasing myosin heavy chains in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns. This study demonstrated that γ-irradiation decreased the myofibrillar protein ordered structure and generated the crosslinking and provided a possible reference for the identification of irradiated fish products.

Size measuring techniques as tool to monitor pea proteins intramolecular crosslinking by transglutaminase treatment.

Science.gov (United States)

Djoullah, Attaf; Krechiche, Ghali; Husson, Florence; Saurel, Rémi

2016-01-01

In this work, techniques for monitoring the intramolecular transglutaminase cross-links of pea proteins, based on protein size determination, were developed. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of transglutaminase-treated low concentration (0.01% w/w) pea albumin samples, compared to the untreated one (control), showed a higher electrophoretic migration of the major albumin fraction band (26 kDa), reflecting a decrease in protein size. This protein size decrease was confirmed, after DEAE column purification, by dynamic light scattering (DLS) where the hydrodynamic radius of treated samples appears to be reduced compared to the control one. Copyright © 2015 Elsevier Ltd. All rights reserved.

Origin of cell surface proteins released from Micrococcus radiodurans by ionizing radiation

International Nuclear Information System (INIS)

Mitchel, R.E.J.

1975-01-01

The exposure of Micrococcus radiodurans to sublethal doses of ionizing radiation causes the release of certain proteins into the surrounding medium. As estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, these proteins range from approximately 20,000 to 125,000 daltons. At least some of the proteins, including an exonuclease, have a surface location and appear to originate from the lipid-rich midwall layer. The exonuclease has two functionally distinct locations, one with its active site available to external substrate and a second with the active site masked from the exterior. Ionizing radiation releases both the masked and unmasked activity into the surrounding medium

Recombinant Brucella abortus gene expressing immunogenic protein

Energy Technology Data Exchange (ETDEWEB)

Mayfield, J.E.; Tabatabai, L.B.

1991-06-11

This patent describes a synthetic recombinant DNA molecule containing a DNA sequence. It comprises a gene of Brucella abortus encoding an immunogenic protein having a molecular weight of approximately 31,000 daltons as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis under denaturing conditions, the protein having an isoelectric point around 4.9, and containing a twenty-five amino acid sequence from its amino terminal end consisting of Gln-Ala-Pro-Thr-Phe-Phe-Arg-Ile-Gly-Thr-Gly-Gly-Thr-Ala-Gly-Thr-Tyr-Tyr-Pro-Ile-Gly-Gly-Leu-Ile-Ala, wherein Gln, Ala, Pro, Thr, Phe, Arg, Ile, Gly, Tyr, and Leu, respectively, represent glutamine, alanine, proline, threonine, phenylalanine, arginine, isolecuine, glycine, tyrosine, and leucine.

Interactions between poly(acrylic acid) and sodium dodecyl sulfate: isothermal titration calorimetric and surfactant ion-selective electrode studies.

Science.gov (United States)

Wang, C; Tam, K C

2005-03-24

Interaction between a monodispersed poly(acrylic acid) (PAA) (M(W) = 5670 g/mol, M(w)/M(n) = 1.02) with sodium dodecyl sulfate (SDS) was investigated using isothermal titration calorimetry (ITC), ion-selective electrode (ISE), and dynamic light scattering measurements. Contrary to previous studies, we report for the first time evidence of interaction between SDS and PAA when the degree of neutralization (alpha) of PAA is lower than 0.2. Hydrocarbon chains of SDS cooperatively bind to apolar segments of PAA driven by hydrophobic interaction. The interaction is both enthalpy and entropy favored (deltaH is negative but deltaS is positive). In 0.05 wt % PAA solution, the SDS concentration corresponding to the onset of binding (i.e., CAC) is approximately 2.4 mM and the saturation concentration (i.e., C(S)) is approximately 13.3 mM when alpha = 0. When PAA was neutralized and ionized, the binding was hindered by the enhanced electrostatic repulsion between negatively charged SDS and PAA chains and improved solubility of the polymer. With increasing alpha to 0.2, CAC increases to approximately 6.2 mM, C(S) drops to 8.6 mM, and the interaction is significantly weakened where the amount of bound SDS on PAA is reduced considerably. The values of CAC and C(S) derived from different techniques are in good agreement. The binding results in the formation of mixed micelles on apolar PAA coils, which then expands and dissociates into single PAA chains. The majority of unneutralized PAA molecules exist as single polymer chains stabilized by bound SDS micelles in solution after the saturation concentration.

Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

Directory of Open Access Journals (Sweden)

A. B. Moldes

2013-01-01

Full Text Available The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-. The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage, as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.

Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

Science.gov (United States)

Moldes, A. B.; Paradelo, R.; Vecino, X.; Cruz, J. M.; Gudiña, E.; Rodrigues, L.; Teixeira, J. A.; Domínguez, J. M.; Barral, M. T.

2013-01-01

The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment. PMID:23691515

Purification of a sarcoplasmic reticulum protein that binds Ca2+ and plasma lipoproteins

International Nuclear Information System (INIS)

Hofmann, S.L.; Brown, M.S.; Lee, E.; Pathak, R.K.; Anderson, R.G.; Goldstein, J.L.

1989-01-01

A protein in the sarcoplasmic reticulum of rabbit skeletal and cardiac muscle was identified because of its ability to bind 125I-labeled low density lipoprotein (LDL) with high affinity after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This protein, referred to as the 165-kDa protein, is restricted to striated muscle. It was not detected in 14 other tissues, including several that contain smooth muscle, but it appears in rat L6 myoblasts when they differentiate into myocytes. Immunofluorescence and immunoelectron microscopic studies revealed that the protein is present throughout the sarcoplasmic reticulum and the terminal cisternae. It binds 45Ca2+ on nitrocellulose blots and stains metachromatically with Stains-all, a cationic dye that stains Ca2+-binding proteins. It does not appear to be a glycoprotein, and it appears slightly larger than the 160-kDa glycoprotein previously described in sarcoplasmic reticulum. The 165-kDa protein binds LDL, beta-migrating very low density lipoprotein, and a cholesterol-induced high density lipoprotein particle that contains apoprotein E as its sole apoprotein with much higher affinity than it binds high density lipoprotein. The protein is stable to boiling and to treatment with sodium dodecyl sulfate, but it becomes sensitive to these treatments when its cystine residues are reduced and alkylated. The protein was purified 1300-fold to apparent homogeneity from rabbit skeletal muscle membranes. It differs from the cell surface LDL receptor in that (1) its apparent molecular weight is not changed by reduction and alkylation; (2) it is present in Watanabe-heritable hyperlipidemic rabbits, which lack functional LDL receptors; (3) binding of lipoproteins is not inhibited by EDTA; and (4) it is located within the lumen of the sarcoplasmic reticulum where it has no access to plasma lipoproteins

Interfacial composition and stability of emulsions made with mixtures of commercial sodium caseinate and whey protein concentrate.

Science.gov (United States)

Ye, Aiqian

2008-10-15

The interfacial composition and the stability of oil-in-water emulsion droplets (30% soya oil, pH 7.0) made with mixtures of sodium caseinate and whey protein concentrate (WPC) (1:1 by protein weight) at various total protein concentrations were examined. The average volume-surface diameter (d32) and the total surface protein concentration of emulsion droplets were similar to those of emulsions made with both sodium caseinate alone and WPC alone. Whey proteins were adsorbed in preference to caseins at low protein concentrations (caseins were adsorbed in preference to whey proteins at high protein concentrations. The creaming stability of the emulsions decreased markedly as the total protein concentration of the system was increased above 2% (sodium caseinate >1%). This was attributed to depletion flocculation caused by the sodium caseinate in these emulsions. Whey proteins did not retard this instability in the emulsions made with mixtures of sodium caseinate and WPC. Copyright © 2008 Elsevier Ltd. All rights reserved.

Study of protein-probe complexation equilibria and protein-surfactant interaction using charge transfer fluorescence probe methyl ester of N,N-dimethylamino naphthyl acrylic acid

Energy Technology Data Exchange (ETDEWEB)

Mahanta, Subrata; Balia Singh, Rupashree; Bagchi, Arnab [Department of Chemistry University of Calcutta 92, A.P.C. Road, Kolkata 700009 (India); Nath, Debnarayan [Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Guchhait, Nikhil, E-mail: nguchhait@yahoo.co [Department of Chemistry University of Calcutta 92, A.P.C. Road, Kolkata 700009 (India)

2010-06-15

In this paper, we demonstrate the interaction between intramolecular charge transfer (ICT) probe-Methyl ester of N,N-dimethylamino naphthyl acrylic acid (MDMANA) with bovine serum albumin (BSA) using absorption and fluorescence emission spectroscopy. The nature of probe protein binding interaction, fluorescence resonance energy transfer from protein to probe and time resolved fluorescence decay measurement predict that the probe molecule binds strongly to the hydrophobic cavity of the protein. Furthermore, the interaction of the anionic surfactant sodium dodecyl sulphate (SDS) with water soluble protein BSA has been investigated using MDMANA as fluorescenece probe. The changes in the spectral characteristics of charge transfer fluorescence probe MDMANA in BSA-SDS environment reflects well the nature of the protein-surfactant binding interaction such as specific binding, non-cooperative binding, cooperative binding and saturation binding.

Effects of bulk colloidal stability on adsorption layers of poly(diallyldimethylammonium chloride)/sodium dodecyl sulfate at the air-water interface studied by neutron reflectometry.

Science.gov (United States)

Campbell, Richard A; Yanez Arteta, Marianna; Angus-Smyth, Anna; Nylander, Tommy; Varga, Imre

2011-12-29

We show for the oppositely charged system poly(diallyldimethylammonium chloride)/sodium dodecyl sulfate that the cliff edge peak in its surface tension isotherm results from the comprehensive precipitation of bulk complexes into sediment, leaving a supernatant that is virtually transparent and a depleted adsorption layer at the air/water interface. The aggregation and settling processes take about 3 days to reach completion and occur at bulk compositions around charge neutrality of the complexes which lack long-term colloidal stability. We demonstrate excellent quantitative agreement between the measured surface tension values and a peak calculated from the surface excess of surfactant in the precipitation region measured by neutron reflectometry, using the approximation that there is no polymer left in the liquid phase. The nonequilibrium nature of the system is emphasized by the production of very different interfacial properties from equivalent aged samples that are handled differently. We go on to outline our perspective on the "true equilibrium" state of this intriguing system and conclude with a comment on its practical relevance given that the interfacial properties can be so readily influenced by the handling of kinetically trapped bulk aggregates. © 2011 American Chemical Society

Surface modification to produce hydrophobic nano-silica particles using sodium dodecyl sulfate as a modifier

Energy Technology Data Exchange (ETDEWEB)

Qiao, Bing; Liang, Yong; Wang, Ting-Jie, E-mail: wangtj@tsinghua.edu.cn; Jiang, Yanping

2016-02-28

Graphical abstract: Nano silica particle was modified to produce hydrophobic surface with contact angle of 107° using the water soluble SDS as a modifier through a new route. The grafted density reached 1.82–2 nm. Brønsted acid sites supply proton to react with SDS via generating carbocation, forming a Si–O–C structure. - Highlights: • Silica was modified to produce hydrophobic surface using SDS as modifier. • The route is free of organic solvent and gets perfect contact of SDS and silica. • Contact angle of modified silica particles reached 107°. • Grafted density on the silica surface reached 1.82 SDS nm{sup −2}. • Brønsted acid sites supply proton to react with SDS via generating carbocation. - Abstract: Hydrophobic silica particles were prepared using the surfactant sodium dodecyl sulfate (SDS) as a modifier by a new route comprising three processes, namely, aqueous mixing, spray drying and thermal treatment. Since SDS dissolves in water, this route is free of an organic solvent and gave a perfect dispersion of SDS, that is, there was excellent contact between SDS and silica particles in the modification reaction. The hydrophobicity of the modified surface was verified by the contact angle of the nano-sized silica particles, which was 107°. The SDS grafting density reached 1.82 nm{sup −2}, which is near the highest value in the literature. The optimal parameters of the SDS/SiO{sub 2} ratio in the aqueous phase, process temperature and time of thermal treatment were determined to be 20%, 200 °C and 30 min, respectively. The grafting mechanism was studied by comparing the modification with that on same sized TiO{sub 2} particles, which indicated that the protons of the Brønsted acid sites on the surface of SiO{sub 2} reacted with SDS to give a carbocation which then formed a Si–O–C structure. This work showed that the hydrophilic surface of silica can be modified to be a hydrophobic surface by using a water soluble modifier SDS in a

Identification and characterization of immunogenic proteins of Mycoplasma genitalium

DEFF Research Database (Denmark)

Svenstrup, Helle Friis; Jensen, J.S.; Gevaert, K.

2006-01-01

serum against M. genitalium G37, determine their identity by mass spectrometry, and develop an M. genitalium-specific enzyme-linked immunosorbent assay (ELISA) free from cross-reactivity with M. pneumoniae antibodies. Using recombinant fragments of the C-terminal part of MgPa (rMgPa), we developed....... genitalium strains were isolated (J. S. Jensen, H. T. Hansen, and K. Lind, J. Clin. Microbiol. 34:286-291, 1996). The objective of this study was to characterize immunogenic proteins of M. genitalium by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting by using a hyperimmune rabbit...

Gastric protein hydrolysis of raw and roasted almonds in the growing pig.

Science.gov (United States)

Bornhorst, Gail M; Drechsler, Krista C; Montoya, Carlos A; Rutherfurd, Shane M; Moughan, Paul J; Singh, R Paul

2016-11-15

Gastric protein hydrolysis may influence gastric emptying rate and subsequent protein digestibility in the small intestine. This study examined the gastric hydrolysis of dietary protein from raw and roasted almonds in the growing pig as a model for the adult human. The gastric hydrolysis of almond proteins was quantified by performing tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis and subsequent image analysis. There was an interaction between digestion time, stomach region, and almond type for gastric protein hydrolysis (palmonds (compared to roasted almonds), hypothesized to be related to structural changes in almond proteins during roasting. Greater gastric protein hydrolysis was observed in the distal stomach (compared to the proximal stomach), likely related to the lower pH in the distal stomach. Copyright © 2016 Elsevier Ltd. All rights reserved.

Downregulation of surface sodium pumps by endocytosis during meiotic maturation of Xenopus laevis oocytes

International Nuclear Information System (INIS)

Schmalzing, G.; Eckard, P.; Kroener, S.P.; Passow, H.

1990-01-01

During meiotic maturation, plasma membranes of Xenopus laevis oocytes completely lose the capacity to transport Na and K and to bind ouabain. To explore whether the downregulation might be due to an internalization of the sodium pump molecules, the intracellular binding of ouabain was determined. Selective permeabilization of the plasma membrane of mature oocytes (eggs) by digitonin almost failed to disclose ouabain binding sites. However, when the eggs were additionally treated with 0.02% sodium dodecyl sulfate (SDS) to permeabilize inner membranes, all sodium pumps present before maturation were recovered. Phosphorylation by [gamma-32P]ATP combined with SDS-polyacrylamide gel electrophoresis (PAGE) and autoradiography showed that sodium pumps were greatly reduced in isolated plasma membranes of eggs. According to sucrose gradient fractionation, maturation induced a shift of sodium pumps from the plasma membrane fraction to membranes of lower buoyant density with a protein composition different from that of the plasma membrane. Endocytosed sodium pumps identified on the sucrose gradient from [3H]ouabain bound to the cell surface before maturation could be phosphorylated with inorganic [32P]phosphate. The findings suggest that downregulation of sodium pumps during maturation is brought about by translocation of surface sodium pumps to an intracellular compartment, presumably endosomes. This contrasts the mechanism of downregulation of Na-dependent cotransport systems, the activities of which are reduced as a consequence of a maturation-induced depolarization of the membrane without a removal of the corresponding transporter from the plasma membrane

Evidence of the protein content of bovine and human dental pulps by the action of endodontic irrigation solutions through electrophoretic patterns

Directory of Open Access Journals (Sweden)

María E López

2013-01-01

Full Text Available Background: Sodium dodecyl sulfate polyacrylamide gel electrophoresis let to show the protein content of different tissues. Dental pulp contains connective tissue which is removed during the endodontic treatment. Many studies consider bovine rather than human pulp tissue because of its size. Aim: To evidence the protein content of bovine and human dental pulps and the action of endodontic irrigation solutions through electrophoretic patterns. Materials and Methods: Extracts of human and bovine dental pulps were prepared. Sodium hypochlorite, calcium hydroxide, chlorhexidine and ethylenediamine tetraacetic acid were used as irrigating solutions. Results: Bovine and human pulps have a small difference in two bands of proteins present between 74 kDa and 80 kDa. The denaturizing capacity of sodium hypochlorite and the washing action of calcium hydroxide and chlorhexidine were evidenced. Ethylenediamine tetraacetic acid solution was shown to contain proteins continuously during the endodontic root canal washing. Conclusions: Differences in pulp tissues and the action of irrigating solutions on their protein content would help on the understanding of the biological process of the endodontic treatment.

Characterization of sodium dodecyl sulfate modified iron pillared montmorillonite and its application for the removal of aqueous Cu(II) and Co(II)

International Nuclear Information System (INIS)

Li Shuzhen; Wu Pingxiao

2010-01-01

Anionic surfactant modified Fe-pillared montmorillonites were prepared by Fe-hydrate solution and sodium dodecyl sulfate (SDS) solution. These organo-inorgano complex montmorillonites were divided into three types (CM1, CM2 and CM3) depending on different intercalation processes. X-ray diffraction spectra, the Fourier transform infrared (FTIR) spectra were used to analyze the structure of the raw and modified montmorillonites. X-ray photoelectron spectra of the simples have been studied to determine spectral characteristics to allow the identification of Fe(III) hydroxide. The specific surface area of the host montmorillonite (M0) is 73.2 m 2 /g, while for the modified montmorillonites it is 114.0 m 2 /g, 117.2 m 2 /g, and 115.8 m 2 /g, respectively. The mesopore volumes of the montmorillonites decrease after modification. Ions of copper and cobalt were selected as adsorbates to evaluate the adsorption performance of each montmorillonite. The adsorption data was analyzed by both Freundlich and Langmuir isotherm models and the data was well fit by the Langmuir isotherm model. The adsorption was efficient and significantly influenced by metal speciation, metal concentration, contact time, and pH. Higher adsorption capacity of the modified montmorillonites were obtained at pH 5-6. The results of desorption indicated that the metal ions were covalently bound to the modified montmorillonites.

Flame atomic absorption spectrometric determination of zinc, nickel, iron and lead in different matrixes after solid phase extraction on sodium dodecyl sulfate (SDS)-coated alumina as their bis (2-hydroxyacetophenone)-1, 3-propanediimine chelates

International Nuclear Information System (INIS)

Ghaedi, M.; Tavallali, H.; Shokrollahi, A.; Zahedi, M.; Montazerozohori, M.; Soylak, M.

2009-01-01

A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in food samples has been reported. The method is based on the adsorption of zinc, nickel, iron and lead on sodium dodecyl sulfate (SDS)-coated alumina, which is also chelated with bis (2-hydroxyacetophenone)-1, 3-propanediimine (BHAPN). The retained analyte ions on modified solid phase were eluted using 8 mL of 4 mol L -1 HNO 3 . The analyte determinations were carried out by flame atomic absorption spectrometry. The influences of some metal ions and anions on the recoveries of understudy analyte ions were investigated. The proposed method has been successfully applied for the evaluation of these trace and toxic metals in some traditional food samples from Iran.

Transfer buffer containing methanol can be reused multiple times in protein electrotransfer.

Science.gov (United States)

Pettegrew, Colin J; Jayini, Renuka; Islam, M Rafiq

2009-04-01

We investigated the feasibility of repeated use of transfer buffer containing methanol in electrotransfer of proteins from sodium dodecyl sulfate-polyacrylamide gels to polyvinylidene difluoride (PVDF) membrane using a prestained protein marker of broad molecular sizes. Transfer of the antitumor protein p53 in HEK293T cell extracts, using fresh and used transfer buffer, followed by detection with anti-p53 antibody was also performed to test detectability in immunoblot. Results from these experiments indicate that the transfer buffer can be reused at least five times and maintain a similar extent of protein transfer to PVDF membrane. Repeated use of the transfer buffer containing methanol will significantly reduce the volume of hazardous waste generated and its disposal cost as well as its adverse effect on environment.

Preparation of the cactus-like porous manganese oxide assisted with surfactant sodium dodecyl sulfate for supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Dai, Yu [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, No. 30 College Road, Beijing 100083 (China); Li, Jianling, E-mail: lijianling@ustb.edu.cn [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, No. 30 College Road, Beijing 100083 (China); Yan, Gang; Xu, Guofeng; Xue, Qingrui [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, No. 30 College Road, Beijing 100083 (China); Kang, Feiyu [Lab of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

2015-02-05

Highlights: • The cactus-like porous MnO{sub 2} was synthesized by hydrothermal method assisted with SDS. • The MnO{sub 2} exhibits a max specific capacitance of 187.8 F g{sup −1} (0.2 A g{sup −1}, 1 M Na{sub 2}SO{sub 4}). • Excellent cycling stability: 92.9% capacitance retention after 1000 cycles. - Abstract: The cactus-like porous manganese dioxide (MnO{sub 2}) was synthesized by a simple hydrothermal method assisted with the surfactant sodium dodecyl sulfate (SDS). The morphology, composition, property of the prepared materials were characterized by X-ray diffraction (XRD), Raman spectroscopy, Brunauer–Emmett–Teller (BET), Field Emission Scanning Electron Microscopy (FE-SEM) and Transmission Electron Microscopy (TEM) measurements. It was found that the sample without surfactant was composed of nanoflakes which piling up together, whereas in the presence of the surfactant, the MnO{sub 2} samples with the max specific surface of 321.9 m{sup 2} g{sup −1} showed a porous cactus-like microstructure, consisted of uniform nanowires and porous nanoflakes. The electrochemical performances of the MnO{sub 2} with and without surfactant were analyzed using Cyclic Voltammetry (CV), Electrochemical Impedance Spectrometry (EIS) and Galvanostatic Charge–Discharge (GCD) tests. The results showed that the MnO{sub 2} assisted with 1 wt.% SDS displayed a higher specific capacitance of 187.8 F g{sup −1} at the current density of 0.2 A g{sup −1} compared with the MnO{sub 2} without surfactant (134.8 F g{sup −1}). And such MnO{sub 2} samples with higher specific capacitance also afford an excellent cyclic stability with the capacity retention of approximately 92.9% after 1000 cycles in 1 M Na{sub 2}SO{sub 4} solution at a current density of 1 A g{sup −1}. The superior capacitive performance of the as-prepared materials could be attributed to its unique cactus-like porous structure, which provided good electronic conductivity, large specific surface area as

Identification of the protein responsible for pyruvate transport into rat liver and heart mitochondria by specific labelling with [3H]N-phenylmaleimide.

OpenAIRE

Thomas, A P; Halestrap, A P

1981-01-01

1. N-Phenylmaleimide irreversibly inhibits pyruvate transport into rat heart and liver mitochondria to a much greater extent than does N-ethylmaleimide, iodoacetate or bromopyruvate. alpha-Cyanocinnamate protects the pyruvate transporter from attack by this thiol-blocking reagent. 2. In both heart and liver mitochondria alpha-cyanocinnamate diminishes labelling by [3H]N-phenylmaleimide of a membrane protein of subunit mol.wt. 15000 on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis...

The influence of sodium lauryl sulfate on the crystal phases of titania by hydrothermal method

Science.gov (United States)

Liu, Chaohong; Wang, Xin

2012-11-01

In this paper, we prepared TiO2 nanostructures by a hydrothermal method and investigated the influence of the SO4^{2-} ion and the effect of long alkyl chains of sodium dodecyl sulfate on the crystal phases of TiO2 by experiments and theoretical calculations. The results indicate that the absorption of the H+HSO4 fragment on rutile (110) is more stable than that of the 2H+SO4 fragment and more favorable to the formation of anatase. The absorption and steric effects of sodium dodecyl sulfate on the surfaces of TiO2 grains also have an important influence on the formation of mixed crystals by changing the speed and the way of octahedral TiO6 units combining. Based on the above facts, we revised the original reaction scheme for crystalline titania formation by previous authors.

Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate (SDS)-coated nano-magnets for the spectrophotometric determination of Fingolomid in biological fluids

Science.gov (United States)

Azari, Zhila; Pourbasheer, Eslam; Beheshti, Abolghasem

2016-01-01

In this study, mixed hemimicelles solid-phase extraction (SPE) based on sodium dodecyl sulfate (SDS)-coated nano-magnets Fe3O4 was investigated as a novel method for the separation and determination of Fingolimod (FLM) in water, urine and plasma samples prior to spectrophotometeric determination. Due to the high surface area of these new sorbents and the excellent adsorption capacity after surface modification by SDS, satisfactory extraction recoveries can be produced. The main factors affecting the adsolubilization of analysts, such as pH, surfactant and adsorbent amounts, ionic strength, extraction time and desorption conditions were studied and optimized. Under the selected conditions, FLM has been quantitatively extracted. The accuracy of the method was evaluated by recovery measurements on spiked samples, and good recoveries of 96%, 95% and 88% were observed for water, urine and plasma respectively. Proper linear behaviors over the investigated concentration ranges of 2-26, 2-17 and 2-13 mg/L with good coefficients of determination, 0.998, 0.997 and 0.995 were achieved for water, urine and plasma samples, respectively. To the best of our knowledge, this is the first time that a mixed hemimicelles SPE method based on magnetic separation and nanoparticles has been used as a simple and sensitive method for monitoring of FLM in water and biological samples.

Two-dimensional polyacrylamide gel analysis of Plodia interpunctella granulosis virus

International Nuclear Information System (INIS)

Russell, D.L.; Consigli, R.A.

1986-01-01

The structural polypeptides of purified Plodia interpunctella granulosis virus were analyzed by three different two-dimensional gel systems. Isoelectric focusing followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed resolution of 53 acidic polypeptides in the enveloped nucleocapsid of the virus ranging in molecular weight from 97,300 to 8000. Nine of these polypeptides were shown to be glycoproteins by the technique of radiolabeled lectin blotting. Separation of the granulin in this system allowed resolution of five species, all of which have identical tryptic peptide maps. This matrix protein was demonstrated to be a phosphoglycoprotein by radiolabeled lectin blotting and acid phosphatase dephosphorylation. Nonequilibrium pH gel electrophoresis followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed resolution of the major basic protein of the virus, VP12, from a more acidic protein of the same molecular weight. Tryptic peptide analysis demonstrated that these two proteins were indeed different and acid urea gels followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed localization of the acidic protein to the envelope and the basic protein to the nucleocapsid of the virus. Finally, probing of the separated envelope nucleocapsid proteins in both the isoelectric focusing and nonequilibrium pH gel electrophoresis two-dimensional systems after transfer to nitrocellulose with iodinated, purified viral proteins allowed further insight into reactions which may be important in the maintenance of the virion structure

Sodium dodecyl sulfate coated γ-alumina support modified by a new Schiff base for solid phase extraction and flame-AAS determination of lead and copper ions

Directory of Open Access Journals (Sweden)

Ardeshir Shokrollahi

2013-01-01

Full Text Available A simple and fast approach for solid phase extraction is herein described, and used to determine trace amounts of Pb2+ and Cu2+ metal ions. The solid phase support is sodium dodecyl sulfate (SDS-coated γ-alumina modified with bis(2-hydroxy acetophenone-1,6-hexanediimine (BHAH ligand. The adsorbed ions were stripped from the solid phase by 6 mL of 4 M nitric acid as eluent. The eluting solution was analyzed by flame atomic absorption spectrometry (FAAS. The sorption recovery of metal ions was investigated with regard to the effects of pH, amount of ligand, γ-alumina and surfactant and the amount and type of eluent. Complexation of BHAH with Pb2+ or Cu2+ ions was examined via spectrophotometry using the HypSpec program. The detection limit for Cu2+ was 7.9 µg L-1 with a relative standard deviation of 1.67%, while that for Pb2+ was 6.4 µg L-1 with a relative standard deviation of 1.64%. A preconcentration factor of 100 was achieved for these ions. The method was successfully applied to determine analyte concentrations in samples of liver, parsley, cabbage, and water.

Chemical characteristics and enhanced hepatoprotective activities of Maillard reaction products derived from milk protein-sugar system.

Science.gov (United States)

Oh, Nam Su; Young Lee, Ji; Lee, Hyun Ah; Joung, Jae Yeon; Shin, Yong Kook; Kim, Sae Hun; Kim, Younghoon; Lee, Kwang Won

2016-02-01

The objective of this study was to investigate the characteristics, antioxidative properties, and hepatoprotective effects of Maillard reaction products (MRP) from milk protein reacted with sugars. The MRP were obtained from milk protein, whey protein concentrates and sodium caseinate, using 2 types of sugars, lactose and glucose, by heating the mixture at 55°C for 7d in a sodium phosphate buffer (pH 7.4). Changes in the chemical modification of the milk protein were monitored by measuring the protein-bound carbonyls and PAGE protein profiles. The results showed that the amount of protein-bound carbonyls increased after Maillard reaction (MR). In addition, sodium dodecyl sulfate-PAGE analysis indicated a formation of high-molecular weight complexes through MR. The modification sites induced by MR of milk protein were monitored by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of tryptic-digested gel spots of MRP. As a result, modification and their localization in AA sequence of MRP was identified. Also, the MRP showed higher antioxidant activities than the intact milk protein, and they reduced intracellular reactive oxygen species production and inhibited the depletion of the reduced glutathione concentrations in the HepG2 cells. In particular, glucose-sodium caseinate MRP showed the highest biological activities among all MRP. Therefore, these results suggest that the MRP from milk protein reacting with sugars possess effective antioxidant activity and have a protective ability against oxidative damage. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Adsorption of sophorolipid biosurfactants on their own and mixed with sodium dodecyl benzene sulfonate, at the air/water interface.

Science.gov (United States)

Chen, Minglei; Dong, Chuchuan; Penfold, Jeff; Thomas, Robert K; Smyth, Thomas J P; Perfumo, Amedea; Marchant, Roger; Banat, Ibrahim M; Stevenson, Paul; Parry, Alyn; Tucker, Ian; Campbell, Richard A

2011-07-19

The adsorption of the lactonic (LS) and acidic (AS) forms of sophorolipid and their mixtures with the anionic surfactant sodium dodecyl benzene sulfonate (LAS) has been measured at the air/water interface by neutron reflectivity, NR. The AS and LS sophorolipids adsorb with Langmuir-like adsorption isotherms. The more hydrophobic LS is more surface active than the AS, with a lower critical micellar concentration, CMC, and stronger surface adsorption, with an area/molecule ∼70 Å(2) compared with 85 Å(2) for the AS. The acidic sophorolipid shows a maximum in its adsorption at the CMC which appears to be associated with a mixture of different isomeric forms. The binary LS/AS and LS/LAS mixtures show a strong surface partitioning in favor of the more surface active and hydrophobic LS component but are nevertheless consistent with ideal mixing at the interface. In contrast, the surface composition of the AS/LAS mixture is much closer to the solution composition, but the surface mixing is nonideal and can be accounted for by regular solution theory, RST. In the AS/LS/LAS ternary mixtures, the surface adsorption is dominated by the sophorolipid, and especially the LS component, in a way that is not consistent with the observations for the binary mixtures. The extreme partitioning in favor of the sophorolipid for the LAS/LS/AS (1:2) mixtures is attributed to a reduction in the packing constraints at the surface due to the AS component. Measurements of the surface structure reveal a compact monolayer for LS and a narrow solvent region for LS, LS/AS, and LS/LAS mixtures, consistent with the more hydrophobic nature of the LS component. The results highlight the importance of the relative packing constraints on the adsorption of multicomponent mixtures, and the impact of the lactonic form of the sophorolipid on the adsorption of the sophorolipid/LAS mixtures.

Bottom-up and Top-down Approaches to Explore Sodium Dodecyl Sulfate and Soluplus on the Crystallization Inhibition and Dissolution of Felodipine Extrudates.

Science.gov (United States)

Chen, Jiali; Chen, Yuqi; Huang, Wencong; Wang, Hanning; Du, Yang; Xiong, Subin

2018-05-05

The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and/or SDS were prepared by hot melt extrusion (HME), and characterized by PLM, DSC and FT-IR. Results indicated that Soluplus inhibited FLDP crystallization and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS(1:2:0.15∼0.3 and 1:3:0.2∼0.4) extrudates. Internal SDS (5%-10%) decreased Tgs of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the non-sink condition of 0.05%SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the non-sink condition. Copyright © 2018. Published by Elsevier Inc.

Identification and characterization of a thermally cleaved fragment of monoclonal antibody-A detected by sodium dodecyl sulfate-capillary gel electrophoresis.

Science.gov (United States)

Kubota, Kei; Kobayashi, Naoki; Yabuta, Masayuki; Ohara, Motomu; Naito, Toyohiro; Kubo, Takuya; Otsuka, Koji

2017-06-05

This report describes a novel, comprehensive approach to identifying a fragment peak of monoclonal antibody-A (mAb-A), detected by sodium dodecyl sulfate-capillary gel electrophoresis (SDS-cGE). The fragment migrated close to the internal standard (10kDa marker) of SDS-cGE and increased about 0.5% under a 25°C condition for 6 months. Generally, identification of fragments observed in SDS-cGE is challenging to carry out due to the difficulty of collecting analytical amounts of fractionations from the capillary. In this study, in-gel digestion peptide mapping and reversed phase liquid chromatography-mass spectrometry (RPLC-MS) were employed to elucidate the structure of the fragment. In addition, a Gelfree 8100 fractionation system was newly introduced to collect the fragment and the fraction was applied to the structural analysis of a mAb for the first time. These three analytical methods showed comparable results, proving that the fragment was a fraction of heavy chain HC1-104. The fragment contained complementarity determining regions (CDRs), which are significant to antigen binding, and thus would affect the efficacy of mAb-A. In addition, SDS-cGE without the 10kDa marker was demonstrated to clarify the increased amount of the fragment, and the experiment revealed that the fragment increases 0.2% per year in storage at 5°C. The combination of the three analytical methodologies successfully identified the impurity peak detected by SDS-cGE, providing information critical to assuring the quality and stability of the biotherapeutics. Copyright © 2017 Elsevier B.V. All rights reserved.

Sodium dodecyl sulfate-ethoxylated polyethylenimine adsorption at the air-water interface: how the nature of ethoxylation affects the pattern of adsorption.

Science.gov (United States)

Batchelor, Stephen N; Tucker, Ian; Petkov, Jordan T; Penfold, Jeffrey; Thomas, Robert K

2014-08-19

The strong interaction between ionic surfactants and polyelectrolytes of opposite charge results in enhanced surface adsorption at the air-water interface down to low surfactant concentrations and in some cases in the formation of ordered surface structures. A notable example which exhibits such properties is the mixture of polyethylenimine, PEI, and sodium dodecyl sulfate, SDS. However, the electrostatic interaction, around charge neutralization, between the surfactant and polymer often results in precipitation or coacervation. This can be mitigated for PEI-surfactant mixtures by ethoxylation of the PEI, but this can also result in a weaker surface interaction and a significant reduction in the adsorption. It is shown here that by localizing the ethoxylation of the PEI into discrete regions of the polymer precipitation upon the addition of SDS is suppressed, the strong surface interaction and enhanced adsorption of the polymer-surfactant mixture is retained. The adsorption of SDS in the presence of ethoxylated PEI is greatly enhanced at low SDS concentrations compared to the adsorption for pure SDS. The adsorption is equally pronounced at pH 7 and 10 and is largely independent of the degree of ethoxylation. Surface ordering, more than monolayer adsorption, is observed over a relatively narrow range of SDS concentrations and is most pronounced at pH 10 and for the polymers with the lower degree of ethoxylation. The results show that ethoxylated PEI's reported here provide a suitable route to enhanced surfactant adsorption while retaining favorable solution properties in which precipitation effects are minimized.

Electrophoretic transfer protein zymography.

Science.gov (United States)

Pan, Daniel; Hill, Adam P; Kashou, Anthony; Wilson, Karl A; Tan-Wilson, Anna

2011-04-15

Zymography detects and characterizes proteolytic enzymes by electrophoresis of protease-containing samples into a nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel containing a copolymerized protein substrate. The usefulness of zymography for molecular weight determination and proteomic analysis is hampered by the fact that some proteases exhibit slower migration through a gel that contains substrate protein. This article introduces electrophoretic transfer protein zymography as one solution to this problem. In this technique, samples containing proteolytic enzymes are first resolved in nonreducing SDS-PAGE on a gel without protein substrate. The proteins in the resolving gel are then electrophoretically transferred to a receiving gel previously prepared with a copolymerized protein substrate. The receiving gel is then developed as a zymogram to visualize clear or lightly stained bands in a dark background. Band intensities are linearly related to the amount of protease, extending the usefulness of the technique so long as conditions for transfer and development of the zymogram are kept constant. Conditions of transfer, such as the pore sizes of resolving and receiving gels and the transfer time relative to the molecular weight of the protease, are explored. Copyright © 2011 Elsevier Inc. All rights reserved.

Analysis of proteins of mouse sarcoma pseudotype viruses: type-specific radioimmunoassays for ecotropic virus p30's

International Nuclear Information System (INIS)

Kennel, S.J.; Tennant, R.W.

1979-01-01

Murine sarcoma virus pseudotypes were prepared by infection of nonproducer cells (A1-2), which were transformed by the Gazdar strain of mouse sarcoma virus, with Gross (N-tropic), WN1802B (B-tropic), or Moloney (NB-tropic) viruses. The respective host range pseudotype sarcoma viruses were defined by the tritration characteristics on cells with the appropriate Fv-1 genotype. Proteins from virus progeny were analyzed by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Bands present in both the 65,000- and the 10,000- to 20,000-molecular-weight regions of the gel distinguished the pseudotype viruses from their respective helpers. Furthermore, two protein bands were noted in the p30 region of murine sarcoma virus (Gross), one corresponding to Gross virus p30, and another of slightly slower mobility. However, since the mobility of the putative sarcoma p30 is nearly indentical to that of WN1802B, its presence could not be established by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Type-specific radioimmunossays for Gross virus p30 and for WN1802B p30 were applied for analysis of pseudotype preparations, and among several ecotropic viruses tested, only the homologous virus scored in the respective assay. By use of these assays, pseudotype viruses were found to contain only 8 to 48% helper-specific p30's; the remainder is presumably derived from the sarcoma virus

Urinary Excretion of Sodium, Nitrogen, and Sugar Amounts Are Valid Biomarkers of Dietary Sodium, Protein, and High Sugar Intake in Nonobese Adolescents.

Science.gov (United States)

Moore, Lori B; Liu, Sarah V; Halliday, Tanya M; Neilson, Andrew P; Hedrick, Valisa E; Davy, Brenda M

2017-12-01

Background: Objective indicators of dietary intake (e.g., biomarkers) are needed to overcome the limitations of self-reported dietary intake assessment methods in adolescents. To our knowledge, no controlled feeding studies to date have evaluated the validity of urinary sodium, nitrogen, or sugar excretion as dietary biomarkers in adolescents. Objective: This investigation aimed to evaluate the validity of urinary sodium, nitrogen, and total sugars (TS) excretion as biomarkers for sodium, protein, and added sugars (AS) intake in nonobese adolescents. Methods: In a crossover controlled feeding study design, 33 adolescents [12-18 y of age, 47 ± 25th percentile (mean ± SD) of body mass index (BMI; in kg/m 2 ) for age] consumed 5% AS [low added sugars (LAS)] and 25% AS [high added sugars (HAS)] isocaloric, macronutrient-matched (55% carbohydrate, 30% fat, and 15% protein) diets for 7 d each, in a randomly assigned order, with a 4-wk washout period between diets. On the final 2 d of each diet period, 24-h urine samples were collected. Thirty-two adolescents completed all measurements (97% retention). Results: Urinary sodium was not different from the expected 90% recovery (mean ± SD: 88% ± 18%, P = 0.50). Urinary nitrogen was correlated with protein intake ( r = 0.69, P sodium appears to be a valid biomarker for sodium intake in nonobese adolescents. Urinary nitrogen is associated with protein intake, but nitrogen excretion rates were less than previously reported for adults, possibly owing to adolescent growth rates. TS excretion reflects AS at 25% AS intake and was responsive to the change in AS intake. Thus, urinary biomarkers are promising objective indicators of dietary intake in adolescents, although larger-scale feeding trials are needed to confirm these findings. This trial was registered at clinicaltrials.gov as NCT02455388. © 2017 American Society for Nutrition.

Bio-solubilization of Chinese lignite II: extra-cellular protein analysis

Energy Technology Data Exchange (ETDEWEB)

Tao, Xiu-xiang; Pan, Lan-ying; Shi, Kai-yi; Chen-hui; Yin, Su-dong; Luo, Zhen-fu [China University of Mining & Technology, Xuzhou (China). School of Chemical Engineering and Technology

2009-05-15

A white rot fungus strain, Trichoderma sp. AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization. The results showed that nitric acid pretreated Fushun lignite was solubilized by T. sp. AH and that extracellular proteins from T. sp. AH were correlated with the lignite bio-solubilization results. In the presence of Fushun lignite the extracellular protein concentration from T. sp. AH was 4.5 g/L while the concentration was 3 g/L in the absence of Fushun lignite. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the extracelular proteins detected at least four new protein bands after the T. sp. AH had solubilized the lignite. Enzyme color reactions showed that extracelular proteins from T. sp. AH mainly consisted of phenol-oxidases, but that lignin decomposition enzymes such as laccase, peroxidase and manganese peroxidases were not present. 9 refs., 8 figs.

Calibration of low molecular weight polypeptides by sodium dodecylsulphate polyacrylamide gel electrophoresis

International Nuclear Information System (INIS)

Glyn, M.C.P.; Bull, J.; Wright, R.

1982-01-01

Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) is a technique commonly used in determining molecular weights of large proteins and peptides. This technique is used to analyse viral peptides, available in amounts too small to be monitored by an ultraviolet spectrophotometer. An experiment is described (with the limiting factor to use the SDS-PAGE technique), to determine the molecular weight peptides and the results are given to fit the linear relationship log M=4.286 - 0.42 V(e)/V(o). The results given by the SDS-PAGE system, described in the article, show that the experimental values describe a linear relationship with good resolution of low molecular weight peptides in the range 3 000 to 14 000 and that a partial cyanogen bromide digest of cytochrome c is suitable for calibration standards

Analysis of protein profiles in diabetic rat blood plasma that induced by alloxan

Science.gov (United States)

Hidayati, Dewi; Abdulgani, Nurlita; Setiyawan, Hengki; Trisnawati, Indah; Ashuri, Nova Maulidina; Sa'adah, Noor Nailis

2017-06-01

Proteomics is the study to identify the proteins involved in physiological metabolic pathway. The protein profiles of blood plasma from alloxan-induced diabetic rats has investigated using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Data were analyzed descriptively based on variations of the type and intensity of the protein. There were identified the similarity of protein variant between diabetic and control rats included ankyrin (200kDa), IgG (150kDa), nephrin (136 kDa), IDE (112 kDA), albumin (66 kDa), prealbumin (55 kDA), CICP (43 kDa), ApoA-V (39 kDa), GAPDH (35 kDa), C-RP (27,1 kDa), leptin (16 kDa) and apelin (13 kDa). However, the apelin profile at diabetic rats shows the higher intensity than control.

Solution pH and oligoamine molecular weight dependence of the transition from monolayer to multilayer adsorption at the air-water interface from sodium dodecyl sulfate/oligoamine mixtures.

Science.gov (United States)

Halacheva, S S; Penfold, J; Thomas, R K; Webster, J R P

2013-05-14

Neutron reflectivity and surface tension have been used to investigate the solution pH and oligoamine molecular weight dependence of the adsorption of sodium dodecyl sulfate (SDS)/oligoamine mixtures at the air-water interface. For diethylenetriamine, triamine, or triethylenetetramine, tetramine mixed with SDS, there is monolayer adsorption at pH 7 and 10, and multilayer adsorption at pH 3. For the slightly higher molecular weight tetraethylenepentamine, pentamine, and pentaethylenehexamine, hexamine, the adsorption is in the form of a monolayer at pH 3 and multilayers at pH 7 and 10. Hence, there is a pH driven transition from monolayer to multilayer adsorption, which shifts from low pH to higher pH as the oligoamine molecular weight increases from tetramine to pentamine. This results from the relative balance between the electrostatic attraction between the SDS and amine nitrogen group which decreases as the charge density decreases with increasing pH, the ion-dipole interaction between the amine nitrogen and SDS sulfate group which is dominant at higher pH, and the hydrophobic interalkyl chain interaction between bound SDS molecules which changes with oligoamine molecular weight.

Investigation and Comparison of Leishmania major Promastigote and Amastigote Protein Content by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis

Directory of Open Access Journals (Sweden)

S. Soleimanifard

2013-04-01

Full Text Available ntroduction & Objective: Leishmania is a protozoan of the trypanosomatidae family. This pro-tozoan has two stages in its life cycle, promastigote form in sand flies and amastigote form in macrophage of mammalian hosts. The purpose of this study was identification and compari-son of proteins of Leishmania amastigote and promastigote stages. Materials & Methods: The present study is a cross sectional study of two forms of Leishmania major. To culture promastigotes , L.major (MRHO/IR/75/ER from previously infected Balb/c mice was transferred to modified N.N.N medium with overlay of liquid BHI and then transferred to RPMI-1640 at 26oc ± 1 for mass production. After isolation and growth, pro-mastigotes were transferred to liquid cell culture medium RPMI-1640 with pH 5.5 and incu-bated at 5% CO2 at 37oc for 72 hours until promastigote to amastigote transformation. Elec-trophoresis was performed with SDS-PAGE method to find and compare the molecular weight of the antigens of two stages. Results: The molecular weights of the bands observed in both forms were as follows: 19, 36, 50, 63, 65, 80, 90, 94, 96, 110- 130 KDa. The proteins in the surface of only promastigote were 22, 28 and 46 KDa and special proteins in the surface of amastigote were 12 and 32 KDa. Conclusion : According to this study Leishmania parasite has stage specific proteins. Various studies have shown that axenic amastigotes and tissue amastigotes are similar in their protein content. Therefore, based on stage specific proteins ,effective drugs and vaccines can be de-signed against leishmaniasis. (Sci J Hamadan Univ Med Sci 2013; 20 (1:1-8

Structure of sodium alkyl sulphate micelles

International Nuclear Information System (INIS)

Vass, Sz.

1990-05-01

Micellar aggregation numbers of aggregated sodium octyl, decyl, dodecyl and tetradecyl sulphate molecules obtained from small-angle neutron scattering (SANS) measurements are reported. The surfactant concentration and solution temperature were varied systematically. A survey of the physical models and evaluation algorithms applied for SANS are presented. By utilizing a new least square fitting algorithm, the formation and annihilation parameters of orthopositronium in the micellar pseudophase and in the aqueous solvent is deduced by evaluating positron lifetime spectra measured by conventional technqiues. (R.P.) 157 refs.; 10 figs

An autoclave treatment reduces the solubility and antigenicity of an allergenic protein found in buckwheat flour.

Science.gov (United States)

Tomotake, Hiroyuki; Yamazaki, Rikio; Yamato, Masayuki

2012-06-01

The effects of an autoclave treatment of buckwheat flour on a 24-kDa allergenic protein were investigated by measuring reduction in solubility and antibody binding. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the intensity of the major bands, including that of the 24-kDa allergen, was reduced by the autoclave treatment. The protein solubility in buckwheat flour was variably decreased by the autoclave treatment. Enzyme-linked immunosorbent assay analysis using a monoclonal antibody specific for buckwheat 24-kDa protein showed that the reactivity of protein extracts (10 μg/ml) from buckwheat flour was lowered by the autoclave treatment. The autoclave treatment may reduce the major allergen content of buckwheat. Future studies will determine if autoclaving treatments affect the allergenicity of the 24-kDa buckwheat protein.

Synthesis of 2,4-dinitrophenylhydrazine loaded sodium dodecyl sulfate-coated magnetite nanoparticles for adsorption of Hg(II ions from an aqueous solution

Directory of Open Access Journals (Sweden)

Soheil Sobhanardakani

2016-09-01

Full Text Available Background: The rapid increase in agricultural and industrial development has made heavy metal pollution a serious environmental problem and public health threat; therefore, removal of heavy metals from water is important. The current study prepared DNPH@SDS@Fe3O4 nanoparticles as a novel and effective adsorbent for removal of Hg(II ions from an aqueous solution. Methods: A selective adsorbent for Hg(II was synthesized by coating Fe3O4 nanoparticles with sodium dodecyl sulfate which was further functionalized with 2,4-dinitrophenylhydrazine (2,4-DNPH. The synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR, x-ray diffraction (XRD, scanning electron microscopy (SEM and SEM–EDXSt. The effects of pH, dose of adsorbent and shaking time on adsorption capacity were investigated. The kinetics and equilibrium of adsorption of the metal ions were thoroughly studied. Results: SEM showed that the size of the nanoparticles was 20 to 35 nm. The maximum adsorption capacity for Hg(II was 164.0 mg g-1 for an adsorbent dose of 0.04 g at pH 7.0, 25°C and the initial metal concentration was 25 mg L-1,which was greater than for most adsorbents previously examined for Hg(II adsorption. Adsorption experimental data showed good correlation with the pseudo-secondorder model and Langmuir isotherm model. Conclusion: The results indicated that the DNPH@SDS@Fe3O4 nanoparticles are an efficient adsorbent for removal of heavy metal from wastewater.

Studying Protein-Protein Interactions by Biotin AP-Tagged Pulldown and LTQ-Orbitrap Mass Spectrometry.

Science.gov (United States)

Xie, Zhongqiu; Jia, Yuemeng; Li, Hui

2017-01-01

The study of protein-protein interactions represents a key aspect of biological research. Identifying unknown protein binding partners using mass spectrometry (MS)-based proteomics has evolved into an indispensable strategy in drug discovery. The classic approach of immunoprecipitation with specific antibodies against the proteins of interest has limitations, such as the need for immunoprecipitation-qualified antibody. The biotin AP-tag pull-down system has the advantage of high specificity, ease of use, and no requirement for antibody. It is based on the high specificity, high affinity interaction between biotin and streptavidin. After pulldown, in-gel tryptic digestion and tandem mass spectrometry (MS/MS) analysis of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) protein bands can be performed. In this work, we provide protocols that can be used for the identification of proteins that interact with FOXM1, a protein that has recently emerged as a potential biomarker and drug target in oncotherapy, as an example. We focus on the pull-down procedure and assess the efficacy of the pulldown with known FOXM1 interactors such as β-catenin. We use a high performance LTQ Orbitrap MSn system that combines rapid LTQ ion trap data acquisition with high mass accuracy Orbitrap analysis to identify the interacting proteins.

Protein Hydrolysis from Catfish Prepared by Papain Enzyme and Antioxidant Activity of Hydrolyzate

Directory of Open Access Journals (Sweden)

Ace Baehaki

2015-12-01

Full Text Available The objective of this research was to make a protein hydrolysates from catfish (Pangasius pangasius enzymatically using papain enzyme and analyzed the antioxidant activity of protein hydrolysates produced. The research used the method completely randomized design with two replications the treatment were the difference concentration of the papain enzyme (0%, 1%, 2%, 3%, 4%, 5%, and 6%. The parameters of research were antioxidative activity using DPPH (2,2-difenil-1–pikrilhidrazil, protein content, and molecular weight using SDS-PAGE (Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis. The results showed that catfish protein hydrolysates prepared by papain enzyme has antioxidative activity. The highest degree of hydrolysis was 71.98% at enzyme concentration of 6%. Based on the DPPH scavenging method catfish protein hydrolysates has the antioxidative activity with the value 37.85-67.62%. The protein content of catfish protein hydrolysates were 20.86-54.47 mg/ml. The molecular weight of catfish protein hydrolyzates were 11.90-65.20 kDa.

Effects of sodium salt types on the intermolecular interaction of sodium alginate/antarctic krill protein composite fibers.

Science.gov (United States)

Zhang, Rui; Guo, Jing; Liu, Yuanfa; Chen, Shuang; Zhang, Sen; Yu, Yue

2018-06-01

Sodium alginate (SA) and antarctic krill protein (AKP) were blended to fabricate the SA/AKP composite fibers by the conventional wet spinning method using 5% CaCl 2 as coagulation solution. The sodium salt was added to the SA/AKP solution to adjust the ionization degree and intermolecular interaction of composite system. The main purpose of this study is to investigate the influences of sodium salt types (NaCl, CH 3 COONa, Na 2 SO 4 ) on the intermolecular interaction of SA/AKP composite fibers. The intermolecular interaction, morphology, crystallinity, thermal stability and mechanical properties of SA/AKP composite fibers were analyzed by fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), x-ray diffraction (XRD), thermogravimetric analysis (TGA). The results show that the types of sodium salt have obvious influences on the content of both β-sheet, intermolecular hydrogen bond, breaking strength and surface morphology in SA/AKP composite fibers, but have a negligible effect on the crystallinity and thermal stability. Copyright © 2018 Elsevier Ltd. All rights reserved.

Selective entrapment of the cationic form of norfloxacin within anionic sodium dodecyl sulfate micelles at physiological pH and its effect on the drug photodecomposition.

Science.gov (United States)

Sortino, Salvatore

2006-01-01

The binding of the photosensitizing fluoroquinolone (FQ) antibiotic norfloxacin (NX) to sodium dodecyl sulfate (SDS) micelles and the photoreactivity of the NX/SDS complex under physiological pH conditions are investigated by means of absorption and emission spectroscopy, steady-state and laser flash photolysis. It is shown that the photolabile zwitterionic form of NX, which is dominant at physiological pH, is not the most abundant species in the presence of SDS micelles. This medium exhibits a high preference for the cationic form of the drug, which is selectively and successfully entrapped within the micellar cage (K(ass) = 6 x 10(4) M(-1) +/- 3000), becoming the largely dominant species at neutral pH. The effect of this trapping is drastically reflected on both efficiency and nature of the drug photodecomposition. It is observed that the photostability of NX incorporated in the micellar pseudophase increases of more than one order of magnitude if compared to that of the "free" drug. Furthermore, the radical photodecomposition mechanism occurring in phosphate buffered solution is suppressed by the micellar medium and the low photodegradation observed seems to take place preferentially through an ionic pathway. Hopefully, the results presented herein may contribute to a better understanding of the bio-distribution of NX in biological systems and provide helpful and stimulating information in order to get the control of FQ photoreactivity under physiological pH conditions.

Transfer in SDS of biotinylated proteins from acrylamide gels to an avidin-coated membrane filter.

Science.gov (United States)

Karlin, Arthur; Wang, Chaojian; Li, Jing; Xu, Qiang

2004-06-01

Avidin was covalently linked to aldehyde-derivatized polyethersulfone membrane filters. These filters were used in Western blot analysis of proteins reacted with biotinylation reagents and electrophoresed in sodium dodecyl sulfate (SDS) on polyacrylamide gels. Electrophoretic transfer from the gels to these filters was in 0.1% SDS, in which the covalently bound avidin retained its biotin-binding capacity. We compared Western blots on avidin-coated membrane filters of biotinylated and nonbiotinylated forms of mouse immunoglobulin G (IgG), mouse IgG heavy chain, muscle-type acetylcholine receptor alpha subunit, and fused alpha and beta subunits of receptor. Biotinylated proteins were captured with high specificity compared to their nonbiotinylated counterparts and sensitively detected on the avidin-coated membranes.

In vivo conjugation of nasal lavage proteins by hexahydrophthalic anhydride

International Nuclear Information System (INIS)

Johannesson, Gunvor; Lindh, Christian; Nielsen, Joern; Bjoerk, Birgitta; Rosqvist, Seema; Joensson, Bo A.G.

2004-01-01

Hexahydrophthalic anhydride (HHPA), an industrially important chemical, is a highly allergenic compound. The aim of this work was to identify proteins in nasal lavage fluid (NLF) that form adducts with HHPA. Such bindings may induce production of specific immunoglobulin E (IgE) or affect physiological mechanisms of the proteins. NLF was obtained from HHPA-exposed volunteers, workers and exposed guinea pigs. HHPA-binding proteins were visualized with immunoblotting using a polyclonal antiserum against HHPA. The proteins were excised from sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) gels, digested with trypsin and identified by tandem mass spectrometry (MS/MS) and database searches. The antiserum was found to be specific for HHPA-bound proteins. In vivo formed HHPA-binding proteins in humans were identified as antileukoproteinase, immunoglobulin G (IgG), immunoglobulin A (IgA), serum albumin and lactoferrin. In addition, several proteins binding to HHPA were found in NLFs from guinea pigs but these could not be identified from database searches. Hypotheses for development of airways diseases by adduction of this allergenic compound to the NLF proteins in humans were established

Characterization of viral proteins of Oryctes baculovirus and comparison between two geographical isolates.

Science.gov (United States)

Mohan, K S; Gopinathan, K P

1989-01-01

Bacilliform Oryctes baculovirus particles have been visualized in electron micrographs of midgut sections from virus infected Oryctes rhinoceros beetles. Morphologically the Indian isolate (Oryctes baculovirus, KI) resembled the previously reported Oryctes baculovirus, isolate PV505. The constituent proteins of baculovirus KI have been analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by Western blots using polyclonal antibodies raised against the complete viral particles, as probes. A total of forty eight viral proteins have been identified. Fourteen viral proteins were located on the viral envelope. Among the proteins constituting the nucleocapsid, three were located internally within the capsid. A 23.5 kDa protein was tightly associated with viral DNA in the nucleocapsid core. Two envelope and seven capsid proteins of KI and PV505 revealed differences in SDS-PAGE profiles and glycosylation patterns. Immunoblotting of KI and PV505 proteins with anti KI antiserum demonstrated antigenic differences between the two viral isolates.

Selective solubilization of membrane proteins differentially labeled by p-chloromercuribenzenesulfonic acid in the presence of sucrose

International Nuclear Information System (INIS)

M'Batchi, B.; Pichelin, D.; Delrot, S.

1987-01-01

Broadbean (Vicia faba L.) leaf discs have been incubated with the slowly permeant thiol reagent [ 203 Hg]-para-chloromercuribenzenesulfonic acid (PCMBS) in the presence or in the absence of sucrose, and the release of PCMBS-labeled proteins has been monitored in media containing various concentrations of urea, ethylene glycol-bis-(β-aminoethyl ether)-N, N, N', N'-tetraacetic acid (EGTA), sodium cholate, sodium dodecyl sulfate, Triton X-100, octylglucoside or (3-[3-cholamidopropyl)-dimethylammonio] 1-propane-sulfonate)(CHAPS). The proteins differentially labeled by PCMBS in the presence of sucrose which, on the basis of previous results, are assumed to included the sucrose carrier, were preferentially solubilized by 1% CHAPS, 1% octylglucoside, or 1% Triton X-100. Other PCMBS-labeled proteins (background proteins) could be partially removed by EGTA, urea, or 0.1% cholate. Sequential treatment by 10 mM EGTA and 1% CHAPS was found to give a fraction highly enriched in the differentially labeled proteins. Analysis of the specific activity of microsomal pellets suggests that the results obtained with leaf discs give a good account of what is occurring at the plasma membrane level. These data, which suggest that the proteins differentially labeled, by PCMBS in the presence of sucrose are intrinsic membrane proteins, can be used to solubilize these proteins from microsomal fractions

Nanodisc-solubilized membrane protein library reflects the membrane proteome.

Science.gov (United States)

Marty, Michael T; Wilcox, Kyle C; Klein, William L; Sligar, Stephen G

2013-05-01

The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membrane proteins and have been used to study a wide variety of purified membrane proteins. This report details the incorporation of an unbiased population of membrane proteins from Escherichia coli membranes into Nanodiscs. This solubilized membrane protein library (SMPL) forms a soluble in vitro model of the membrane proteome. Since Nanodiscs contain isolated proteins or small complexes, the SMPL is an ideal platform for interactomics studies and pull-down assays of membrane proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the protein population before and after formation of the Nanodisc library indicates that a large percentage of the proteins are incorporated into the library. Proteomic identification of several prominent bands demonstrates the successful incorporation of outer and inner membrane proteins into the Nanodisc library.

Strain specific variation of outer membrane proteins of wild Yersinia pestis strains subjected to different growth temperatures

Directory of Open Access Journals (Sweden)

Frederico Guilherme Coutinho Abath

1990-03-01

Full Text Available Three Yersinia pestis strains isolated from humans and one laboratory strain (EV76 were grown in rich media at 28§C and 37§C and their outer membrane protein composition compared by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-Page. Several proteins with molecular weights ranging from 34 kDa to 7 kDa were observed to change in relative abundance in samples grown at different temperatures. At least seven Y. pestis outer membrane proteins showed a temperature-dependent and strain-specific behaviour. Some differences between the outer membrane proteins of full-pathogenic wild isolates and the EV76 strain could aldso be detected and the relevance of this finding on the use of laboratory strains as a reference to the study of Y. pestis biological properties is discuted.

Solubilization of rat kidney plasma membrane proteins associated with 3H-aldosterone

International Nuclear Information System (INIS)

Ozegovic, B.; Dobrovic-Jenik, D.; Milkovic, S.

1988-01-01

The treatment of rat kidney plasma membranes with sodium dodecyl sulphate (SDS) did not essentially affect the ability of the membranes for 3 H-aldosterone binding as compared with the intact plasma membranes (Ozegovic et al., 1977). A gel filtration of 3 H-aldosterone - kidney plasma membranes complex on Sepharose 6B yielded 2 protein and 2 3 H-aldosterone peaks. The proteins which were eluted in the first peak were associated with the first 3 H-aldosterone peak while the second 3 H-aldosterone peak was eluted with Ve corresponding to Ve of free 3 H-aldosterone. Spironolactone, a competitive antagonist of aldosterone, prevented the binding of 3 H-aldosterone to the membrane proteins. The results demonstrated a high affinity of the kidney plasma membranes solubilized with SDS and a specificity of aldosterone binding to the plasma membrane proteins of higher molecular mass. (author)

Molecular Level Understanding of Sodium Dodecyl Sulfate (SDS) Induced Sol-Gel Transition of Pluronic F127 Using Fisetin as a Fluorescent Molecular Probe.

Science.gov (United States)

Mishra, Jhili; Swain, Jitendriya; Mishra, Ashok Kumar

2018-01-11

The thermoreversible sol-gel transition of pluronic F127 is markedly altered even with addition of submicellar concentration of sodium dodecyl sulfate (SDS) surfactant. Multiple fluorescence parameters like fluorescence intensity, fluorescence anisotropy and fluorescence lifetime of both the prototropic forms (anion (A - *) and phototautomer FT*) of the photoprototropic fluorescent probe fisetin has been efficiently used to understand the molecular level properties like polarity and microviscosity of the PF127-SDS system as a function of temperature. The SDS-induced increase in the interfacial hydrophobicity level is seen to affect the sol-gel phase transition of PF127 (21-18 °C). The E T (30) polarity parameter value of anionic emission of fisetin suggests that there is a considerable decrease in the polarity of the PF127 medium with increase in temperature and with the addition of SDS. The microviscosity progressively increases from ∼5 mPa s (sol state, 10 °C) to ∼22.01 mPa s (gel state 35 °C) in aqueous solution of PF127. The variation in microviscosity with addition of SDS in PF127-SDS mixed system is significant in sol phase whereas in gel phase this variation is significantly less. Temperature dependent fluorescence lifetime of FT* indicates that there is heterogeneity in distribution of fisetin molecules at different domains of PF127. This work also show-cases the sensitivity of fisetin toward change in polarity and change in sol-gel transition temperature of copolymer PF127 with variation in temperature (both forward and reverse directions) and SDS.

Identification and analysis of multi-protein complexes in placenta.

Directory of Open Access Journals (Sweden)

Fuqiang Wang

Full Text Available Placental malfunction induces pregnancy disorders which contribute to life-threatening complications for both the mother and the fetus. Identification and characterization of placental multi-protein complexes is an important step to integratedly understand the protein-protein interaction networks in placenta which determine placental function. In this study, blue native/sodium dodecyl sulfate polyacrylamide gel electrophoresis (BN/SDS-PAGE and Liquid chromatography-tandem mass spectrometry (LC-MS/MS were used to screen the multi-protein complexes in placenta. 733 unique proteins and 34 known and novel heterooligomeric multi-protein complexes including mitochondrial respiratory chain complexes, integrin complexes, proteasome complexes, histone complex, and heat shock protein complexes were identified. A novel protein complex, which involves clathrin and small conductance calcium-activated potassium (SK channel protein 2, was identified and validated by antibody based gel shift assay, co-immunoprecipitation and immunofluorescence staining. These results suggest that BN/SDS-PAGE, when integrated with LC-MS/MS, is a very powerful and versatile tool for the investigation of placental protein complexes. This work paves the way for deeper functional characterization of the placental protein complexes associated with pregnancy disorders.

The corrosion inhibition of aluminum and its copper alloys in 1.0 M H2SO4 solution using linear-sodium dodecyl benzene sulfonate as inhibitor

International Nuclear Information System (INIS)

Abd El Rehim, Sayed S.; Amin, Mohammed A.; Moussa, S.O.; Ellithy, Abdallah S.

2008-01-01

The corrosion inhibition of Al and its two copper alloys are the subject of tremendous technological importance due to the increased industrial applications of these materials. This paper reports the results of potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements on the corrosion inhibition of Al (Al-2.5% Cu and Al-7.0% Cu) alloys in 1.0 M H 2 SO 4 solution carried out in different concentrations of linear-sodium dodecyl benzene sulfonate as an anionic surfactant (LAS) and temperature range from 10 to 60 deg. C. The data revealed that the inhibition efficiency increases with increasing surfactant concentration and time of immersion, and decreases with solution temperature. Energy dispersion X-ray (EDX) observations of the electrode surface confirmed the existence of LAS adsorbed film on the electrode surface. The surfactant acted mainly as cathodic inhibitor. Maximum inhibition efficiency of the surfactant is observed at concentration around its critical micelle concentration (CMC). The inhibition occurs through adsorption of the surfactant on the metal surface without modifying the mechanism of the corrosion process, which tested by UV-spectroscopy. The potential of zero charge (PZC) of aluminum and Al-7.0% Cu was studied by ac-impedance, and the mechanism of adsorption is discussed. The adsorption isotherm is described by Temkin adsorption isotherm. Thermodynamic functions for activation and adsorption process were determined

Ultrastructural and biochemical investigations of protein mobilization of Mucuna pruriens (L.) DC. cotyledons and embryo axis.

Science.gov (United States)

Muccifora, Simonetta; Guerranti, Roberto; Muzzi, Chiara; Hope-Onyekwere, Nnadozies S; Pagani, Roberto; Leoncini, Roberto; Bellani, Lorenza M

2010-03-01

The mobilization of storage reserves, with particular emphasis on storage proteins of Mucuna pruriens (L.) DC., cotyledons, and embryo was investigated from the ultrastructural and biochemical points of view. Proteins and starch were the two main storage substances in cotyledons, and proteins and lipids were the main ones in the embryo. Embryo protein bodies were smaller and fewer in number than those of cotyledons. Structural and ultrastructural data determined between 24 and 48 h after imbibition and between 48 and 72 h after imbibition, the end of significant embryo and cotyledon protein mobilization, respectively, indicating more precocious storage protein mobilization in the axis than cotyledons. Moreover, storage protein mobilization in embryo and cotyledons occurred before the end of germination. Water soluble proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, producing 29 bands with molecular weights from 14 to 90 KDa. Embryo extract contained more proteins than cotyledon extract, contained seven characteristic bands, and showed a higher variability of the optical density trend than cotyledon.

Inhibition of Nonenzymatic Protein Glycation by Pomegranate and Other Fruit Juices

Science.gov (United States)

Dorsey, Pamela Garner; Greenspan, Phillip

2014-01-01

Abstract The nonenzymatic glycation of proteins and the formation of advanced glycation endproducts in diabetes leads to the crosslinking of proteins and disease complications. Our study sought to demonstrate the effect of commonly consumed juices (pomegranate, cranberry, black cherry, pineapple, apple, and Concord grape) on the fructose-mediated glycation of albumin. Albumin glycation decreased by 98% in the presence of 10 μL of pomegranate juice/mL; other juices inhibited glycation by only 20%. Pomegranate juice produced the greatest inhibition on protein glycation when incubated at both the same phenolic concentration and the same antioxidant potential. Both punicalagin and ellagic acid significantly inhibited the glycation of albumin by ∼90% at 5 μg/mL. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis revealed that pomegranate, but not apple juice, protected albumin from modification. These results demonstrate that pomegranate juice and two of its major constituents are potent inhibitors of fructose-mediated protein glycation. PMID:24433074

Bone sialoprotein II synthesized by cultured osteoblasts contains tyrosine sulfate

International Nuclear Information System (INIS)

Ecarot-Charrier, B.; Bouchard, F.; Delloye, C.

1989-01-01

Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with [35S] sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I

Antitumor activity of physcion 8-o-β-glucopyranoside against ...

African Journals Online (AJOL)

harvested and total proteins were extracted with cell lysis buffer for western and IP. Subsequently, the protein concentration was determined by the. BCA protein assay kit. Then, equal amount of total protein (40 μg) were separated by the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE). After that, all.

Analysis of protein profile and pollen morphology of guaiacum officinale linn

International Nuclear Information System (INIS)

Zeb, S.

2017-01-01

Asthma and allergic rhinitis is triggered by the pollen of trees, grasses and weeds. Guaiacum officinale L. tree is widely cultivated along with the road side. This species was selected to check its allergenic role.Pollen morphology of Guaiacum officinale was examined by Light microsco4pe (LM) and Scanning electron microscope (SEM). Pollen grains of Guaiacum officinale were prolate shape, having tricolpate aperture, and rugulate tectum. Pollen protein concentration of G. officinale was determined by Bradford's assay and qualitative protein analysis of pollen was done by SDS-PAGE(Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis).Total protein content in the pollen extract was 24.28mg/g of pollen. The SDS-PAGE pollen grains protein analysis showed 07 different protein bands. The molecular weight of separated proteins ranged from 25 to 65kDa. Biochemical analysis of G. officinale pollen grains revealed the presence of low molecular weight proteins therefore it is strongly suggested that this species must be considered as a potent allergy causing species. This research would help for the proper diagnosis and treatment of the bronchial allergy suffering patients. (author)

Interactions between whey proteins and salivary proteins as related to astringency of whey protein beverages at low pH.

Science.gov (United States)

Ye, A; Streicher, C; Singh, H

2011-12-01

Whey protein beverages have been shown to be astringent at low pH. In the present study, the interactions between model whey proteins (β-lactoglobulin and lactoferrin) and human saliva in the pH range from 7 to 2 were investigated using particle size, turbidity, and ζ-potential measurements and sodium dodecyl sulfate-PAGE. The correlation between the sensory results of astringency and the physicochemical data was discussed. Strong interactions between β-lactoglobulin and salivary proteins led to an increase in the particle size and turbidity of mixtures of both unheated and heated β-lactoglobulin and human saliva at pH ∼3.4. However, the large particle size and high turbidity that occurred at pH 2.0 were the result of aggregation of human salivary proteins. The intense astringency in whey protein beverages may result from these increases in particle size and turbidity at these pH values and from the aggregation and precipitation of human salivary proteins alone at pH salivary proteins in the interaction is a key factor in the perception of astringency in whey protein beverages. At any pH, the increases in particle size and turbidity were much smaller in mixtures of lactoferrin and saliva, which suggests that aggregation and precipitation may not be the only mechanism linked to the perception of astringency in whey protein. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of protein-surfactant interactions on aggregation of β-lactoglobulin.

Science.gov (United States)

Hansted, Jon G; Wejse, Peter L; Bertelsen, Hans; Otzen, Daniel E

2011-05-01

The milk protein β-lactoglobulin (βLG) dominates the properties of whey aggregates in food products. Here we use spectroscopic and calorimetric techniques to elucidate how anionic, cationic and non-ionic surfactants interact with bovine βLG and modulate its heat-induced aggregation. Alkyl trimethyl ammonium chlorides (xTAC) strongly promote aggregation, while sodium alkyl sulfates (SxS) and alkyl maltopyranosides (xM) reduce aggregation. Sodium dodecyl sulfate (SDS) binds to non-aggregated βLG in several steps, but reduction of aggregation was associated with the first binding step, which occurs far below the critical micelle concentration. In contrast, micellar concentrations of xMs are required to reduce aggregation. The ranking order for reduction of aggregation (normalized to their tendency to self-associate) was C10-C12>C8>C14 for SxS and C8>C10>C12>C14>C16 for xM. xTAC promote aggregation in the same ranking order as xM reduce it. We conclude that SxS reduce aggregation by stabilizing the protein's ligand-bound state (the melting temperature t(m) increases by up to 10°C) and altering its charge potential. xM monomers also stabilize the protein's ligand-bound state (increasing t(m) up to 6°C) but in the absence of charged head groups this is not sufficient by itself to prevent aggregation. Although micelles of both anionic and non-ionic surfactants destabilize βLG, they also solubilize unfolded protein monomers, leaving them unavailable for protein-protein association and thus inhibiting aggregation. Cationic surfactants promote aggregation by a combination of destabilization and charge neutralization. The food compatible surfactant sodium dodecanoate also inhibited aggregation well below the cmc, suggesting that surfactants may be a practical way to modulate whey protein properties. Copyright © 2011 Elsevier B.V. All rights reserved.

A single-step simultaneous protein staining procedure for polyacrylamide gels and nitrocellulose membranes by Alta during western blot analysis.

Science.gov (United States)

Pal, Jayanta K; Berwal, Sunil K; Soni, Rupali N

2012-01-01

A simple method for staining of proteins simultaneously on sodium dodecyl sulfate (SDS) polyacrylamide gels and nitrocellulose membranes by Alta during western blot analysis is described. A 5% solution of Alta, a commercially available cosmetic preparation, is added in the upper tank buffer during electrophoresis. On completion of electrophoresis, the gel is washed in distilled water and viewed on a white light plate and a transilluminator to photograph the protein profiles. The gel is processed for western blot transfer of proteins onto a nitrocellulose membrane, and upon completion, the protein profiles on the membrane are viewed and photographed as stated above. The membrane can then be processed for immunostaining as per the standard procedure. Thus, the staining procedure using Alta is simple, rapid (without any need of destaining), and cost-effective.

Isolation and Characterization of Antithrombin Peptides from the ...

African Journals Online (AJOL)

The molecular weights of isolated active compounds were identified using tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS- PAGE). Results: More than 40 proteins were isolated from LSC using RP-HPLC. Two compounds (protein 1 and protein 2) were found to be active as they increased thrombin ...

Ecotoxicological assessment of the pharmaceutical fluoxetine hydrochloride and the surfactant dodecyl sodium sulfate after their submission to ionizing radiation treatment; Avaliacao ecotoxicologica do farmaco cloridrato de fluoxetina e do surfactante dodecil sulfato de sodio quando submetidos a tratamento por radiacao ionizante

Energy Technology Data Exchange (ETDEWEB)

Santos, Dymes Rafael Alves dos

2011-07-01

The use of pharmaceuticals and personal care products and the consequent and continuous input of this substances in the environment generates an increasing need to investigate the presence, behavior and the effects on aquatic biota, as well as new ways to treat effluents containing such substances. Fluoxetine hydrochloride is an active ingredient used in the treatment of depressive disorders and anxiety. As the surfactant sodium dodecyl sulfate is present in many cleaning and personal care products. The present study aimed on assessing the acute toxicity of fluoxetine hydrochloride, sodium dodecyl sulfate and the mixture of both to the aquatic organisms Hyalella azteca, Daphnia similis and Vibrio ficheri. Reducing the toxicity of fluoxetine and the mixture after treatment with ionizing radiation from industrial electron beam accelerator has also been the focus of this study. For Daphnia similis the average values of CE50-4{sub 8h} found for the non-irradiated drug, surfactant and mixture were 14.4 %, 9.62 % and 13.8 %, respectively. After irradiation of the substances, the dose 5 kGy proved itself to be the most effective dose for the treatment of the drug and the mixture as it was obtained the mean values for CE50{sub 48h} 84.60 % and > 90 %, respectively. For Hyalella azteca the acute toxicity tests were performed for water column with duration of 96 hours, the mean values for CE50{sub 96h} found for the drug, the surfactant and the mixture non-irradiated were 5.63 %, 19.29 %, 6.27 %, respectively. For the drug fluoxetine and the mixture irradiated with 5 kGy, it was obtained 69.57 % and 77.7 %, respectively. For Vibrio ficheri the acute toxicity tests for the untreated drug and the drug irradiated with 5 kGy it was obtained CE50{sub 15min} of 6.9 % and 32.88 % respectively. These results presented a reduction of the acute toxicity of the test-substances after irradiation. (author)

Structuring detergents for extracting and stabilizing functional membrane proteins.

Directory of Open Access Journals (Sweden)

Rima Matar-Merheb

Full Text Available BACKGROUND: Membrane proteins are privileged pharmaceutical targets for which the development of structure-based drug design is challenging. One underlying reason is the fact that detergents do not stabilize membrane domains as efficiently as natural lipids in membranes, often leading to a partial to complete loss of activity/stability during protein extraction and purification and preventing crystallization in an active conformation. METHODOLOGY/PRINCIPAL FINDINGS: Anionic calix[4]arene based detergents (C4Cn, n=1-12 were designed to structure the membrane domains through hydrophobic interactions and a network of salt bridges with the basic residues found at the cytosol-membrane interface of membrane proteins. These compounds behave as surfactants, forming micelles of 5-24 nm, with the critical micellar concentration (CMC being as expected sensitive to pH ranging from 0.05 to 1.5 mM. Both by 1H NMR titration and Surface Tension titration experiments, the interaction of these molecules with the basic amino acids was confirmed. They extract membrane proteins from different origins behaving as mild detergents, leading to partial extraction in some cases. They also retain protein functionality, as shown for BmrA (Bacillus multidrug resistance ATP protein, a membrane multidrug-transporting ATPase, which is particularly sensitive to detergent extraction. These new detergents allow BmrA to bind daunorubicin with a Kd of 12 µM, a value similar to that observed after purification using dodecyl maltoside (DDM. They preserve the ATPase activity of BmrA (which resets the protein to its initial state after drug efflux much more efficiently than SDS (sodium dodecyl sulphate, FC12 (Foscholine 12 or DDM. They also maintain in a functional state the C4Cn-extracted protein upon detergent exchange with FC12. Finally, they promote 3D-crystallization of the membrane protein. CONCLUSION/SIGNIFICANCE: These compounds seem promising to extract in a functional state

UVA photolysis using the protein-bound sensitizers present in human lens

International Nuclear Information System (INIS)

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

1994-01-01

This research was undertaken to demonstrate that the protein-bound chromophores in aged human lens can act as sensitizers for protein damage by UVA light. The water-insoluble (WI) proteins from pooled human and bovine lenses were solubilized by sonication in water and illuminated with UV light similar in output to that transmitted by the cornea. Analysis of the irradiated proteins showed a linear decrease in sulfhydryl groups with a 30% loss after 2 h. No loss was seen when native α-crystallin was irradiated under the same conditions. A 25% loss of histidine residues was also observed with the human lens WI fraction, and sodium dodecyl sulfate polyacrylamide gels indicated considerable protein cross-linking. Similar photodamage was seen with a WI fraction from old bovine lenses. While the data show the presence of UVA sensitizers, some histidine destruction and protein cross-linking were also obtained with α-crystallin and with lysozyme which argue that part of the histidine loss in the human WISS was likely due to tryptophan acting as a sensitizer. (Author)

Properties of adenyl cyclase and cyclic adenosine 3',5'-monophosphate receptor protein-deficient mutants of Escherichia coli

International Nuclear Information System (INIS)

Kumar, S.

1976-01-01

Several spontaneous cya and crp mutants of Escherichia coli have been selected as clones simultaneously resistant to phage lambda and nalidixic acid and characterized. Both cya and crp mutants have been found to grow as cocci with increased doubling times. They have increased resistance to some mutagens (methylmethanesulfonate, ultraviolet light, gamma rays), antibiotics (nalidixic acid, ampicillin), phages (lambda, T6), sublethal heat and hypotonic shock, and decreased resistance to neutral detergents (sodium dodecyl sulfate, sodium deoxycholate), a protein synthesis inhibitor (streptomycin), and a respiratory inhibitor (sodium azide). The nature of changes in cell parameters indicate fundamental alterations in the envelope structure of the cya and crp mutant cells. The new cya and crp mutants have been found to be multiply carbohydrate negative and nonmotile in conformity with similar previously isolated mutants. Studies of revertants and phi 80 cya + and phi 80 cya transductants indicated that the pleiotropic phenotype is related to a single mutational event at the cya or the crp locus in the mutants

Efficacy and compatibility with mass spectrometry of methods for elution of proteins from sodium dodecyl sulfate-polyacrylamide gels and polyvinyldifluoride membranes

DEFF Research Database (Denmark)

Jørgensen, C.S.; Jagd, M.; Sørensen, B.K.

2004-01-01

projects. As a result of this, methods for postelectrophoretic protein characterization are of Great interest as exemplified by in situ protease digestion combined with mass spectrometry (MS), which is the method of choice for identification of proteins. In this study we have developed and compared methods...... for recovering intact proteins from polyacrylamide gels and electroblotting membranes to define efficient methods compatible with MS. These methods complement in situ digestion protocols and allow determination of the molecular mass of whole proteins separated by SDS-PAGE. Passive elution of proteins from SDS......-PAGE gels was efficient only in the presence of SDS, whereas electroelution was achieved using butTers without SDS. Surface-enhanced laser desorption/ionization MS (SELDI-MS) analysis of proteins eluted in the presence of SIDS was possible using ion exchange ProteinChip arrays for concentration of sample...

Characterisation and functional properties of watermelon (Citrullus lanatus) seed proteins.

Science.gov (United States)

Wani, Ali Abas; Sogi, Dalbir Singh; Singh, Preeti; Wani, Idrees Ahmed; Shivhare, Uma S

2011-01-15

People in developing countries depend largely on non-conventional protein sources to augment the availability of proteins in their diets. Watermelon seed meal is reported to contain an adequate amount of nutritional proteins that could be extracted for use as nutritional ingredients in food products. Osborne classification showed that globulin was the major protein (≥500 g kg (-1)) present in watermelon seed meal, followed by albumin and glutelin. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that the polypeptides had low molecular weights ranging from 35 to 47 kDa. Isoelectric focusing revealed that the isoelectric point of most proteins was in the acidic range 4-6. These proteins are rich in aspartic acid, glutamic acid and serine. An increase in pH (5-9) significantly (P watermelon protein fractions respectively, while surface hydrophobicity ranged from 126.4 to 173.2 and from 125.8 to 169.3 respectively. The foaming and emulsifying properties of albumin were better than those of the other proteins studied. The good nutritional and functional properties of watermelon seed meal proteins suggest their potential use in food formulations. Copyright © 2010 Society of Chemical Industry.

Electrophoretic extraction of low molecular weight cationic analytes from sodium dodecyl sulfate containing sample matrices for their direct electrospray ionization mass spectrometry.

Science.gov (United States)

Kinde, Tristan F; Lopez, Thomas D; Dutta, Debashis

2015-03-03

While the use of sodium dodecyl sulfate (SDS) in separation buffers allows efficient analysis of complex mixtures, its presence in the sample matrix is known to severely interfere with the mass-spectrometric characterization of analyte molecules. In this article, we report a microfluidic device that addresses this analytical challenge by enabling inline electrospray ionization mass spectrometry (ESI-MS) of low molecular weight cationic samples prepared in SDS containing matrices. The functionality of this device relies on the continuous extraction of analyte molecules into an SDS-free solvent stream based on the free-flow zone electrophoresis (FFZE) technique prior to their ESI-MS analysis. The reported extraction was accomplished in our current work in a glass channel with microelectrodes fabricated along its sidewalls to realize the desired electric field. Our experiments show that a key challenge to successfully operating such a device is to suppress the electroosmotically driven fluid circulations generated in its extraction channel that otherwise tend to vigorously mix the liquid streams flowing through this duct. A new coating medium, N-(2-triethoxysilylpropyl) formamide, recently demonstrated by our laboratory to nearly eliminate electroosmotic flow in glass microchannels was employed to address this issue. Applying this surface modifier, we were able to efficiently extract two different peptides, human angiotensin I and MRFA, individually from an SDS containing matrix using the FFZE method and detect them at concentrations down to 3.7 and 6.3 μg/mL, respectively, in samples containing as much as 10 mM SDS. Notice that in addition to greatly reducing the amount of SDS entering the MS instrument, the reported approach allows rapid solvent exchange for facilitating efficient analyte ionization desired in ESI-MS analysis.

The effect of aging on mitochondrial proteins in germinating soybean embryonic axes

International Nuclear Information System (INIS)

Furman, K.C.

1988-01-01

Aging-induced deterioration is a major problem associated with seed storage. Impairment of mitochondrial function is one of the first effects of aging. The composition and synthesis of nuclear and mito-coded mitochondrial proteins from soybean (Glycine max. L. Merr.) embryonic axes were studied to elucidate the cause of impaired respiratory development during germination of aged seeds. Axes excised from high vigor (HV) seeds and aged or low vigor (LV) seeds were protected from imbibition injury and germinated for various times, or excised from developing seeds, and then radiolabeled for one hour in [ 35 S]methionine. Mitochondria were then isolated and total mitochondrial protein was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by quantitative staining and fluorography of labeled polypeptides. Alternatively, an original two-dimensional native-to-denaturing gel electrophoretic technique was used to analyze native protein associations and to purify a 23 kD polypeptide

Procedures for two-dimensional electrophoresis of proteins

Energy Technology Data Exchange (ETDEWEB)

Tollaksen, S.L.; Giometti, C.S.

1996-10-01

High-resolution two-dimensional gel electrophoresis (2DE) of proteins, using isoelectric focusing in the first dimension and sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) in the second, was first described in 1975. In the 20 years since those publications, numerous modifications of the original method have evolved. The ISO-DALT system of 2DE is a high-throughput approach that has stood the test of time. The problem of casting many isoelectric focusing gels and SDS-PAGE slab gels (up to 20) in a reproducible manner has been solved by the use of the techniques and equipment described in this manual. The ISO-DALT system of two-dimensional gel electrophoresis originated in the late 1970s and has been modified many times to improve its high-resolution, high-throughput capabilities. This report provides the detailed procedures used with the current ISO-DALT system to prepare, run, stain, and photograph two-dimensional gels for protein analysis.

Effect of Sodium Dodecyl Sulfate (SDS) and Tween 80 on Cell Viability in an Air-Cathode Microbial Fuel Cell

KAUST Repository

Fregoso, Luisa

2011-07-01

Microbial fuel cells (MFCs) generate current via electrochemical reactions produced by bacteria attached to the anode that oxidize organic matter. Due to their high volume use in household products, some concentration of surfactant will reach wastewater treatment plants. The average surfactant concentration in wastewater ranges from 10 to 20 mg L-1, and up to 300 mg L-1, for domestic and industrial wastewaters, respectively. This study aimed to demonstrate the feasibility of enhancing power production by adding Tween 80 and SDS surfactants to air-cathode MFCs, and their effect in cell viability at the anodic biofilm. In order to analyze the effect of anionic and nonionic surfactants in MFCs performance, eight MFCs were spiked with two types of surfactants, the anionic surfactant sodium dodecyl sulfate (SDS) and the nonionic surfactant Tween® 80 at two different concentrations 10 and 100 mg L-1. Cell viability at the anodic biofilms was examined using the LIVE/DEAD BacLight viability assay and images were visualized with a confocal laser scanning microscope. The electrochemical results demonstrate that, for an air-cathode MFC operating on 1 g L-1 acetate in a fed-batch mode, reactors where SDS was added show a lower overall performance, maximum PD of 544 mW m-2, CE of 12.3%, Rint of 322 Ω (10 mg L-1) and maximum PD of 265 mW m-2, CE of 9.4%, Rint of 758 Ω (100 mg L-1). Reactors where Tween 80 was added show quite stable performance, maximum PD of 623 mW m-2, CE of 15.4%, Rint of 216 Ω (10 mg L-1) and maximum PD of 591 mW m-2, CE of 10.8%, Rint of 279 Ω (100 mg L-1), compared with reactors operating at only acetate as a substrate, maximum PD of 574 mW m-2. Confocal microscopy images confirm this observation and biofilm viability appeared severely compromised in SDS reactors, especially at high concentrations. This study has opened up a whole new research area in determining which types of surfactants are toxic to the anodic biofilm and to further investigate the

Proteomic detection of oxidized and reduced thiol proteins in cultured cells.

Science.gov (United States)

Cuddihy, Sarah L; Baty, James W; Brown, Kristin K; Winterbourn, Christine C; Hampton, Mark B

2009-01-01

The oxidation and reduction of cysteine residues is emerging as an important post-translational control of protein function. We describe a method for fluorescent labelling of either reduced or oxidized thiols in combination with two-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (2DE) to detect changes in the redox proteome of cultured cells. Reduced thiols are labelled with the fluorescent compound 5-iodoacetamidofluorescein. To monitor oxidized thiols, the reduced thiols are first blocked with N-ethyl-maleimide, then the oxidized thiols reduced with dithiothreitol and labelled with 5-iodoacetamidofluorescein. The method is illustrated by treating Jurkat T-lymphoma cells with hydrogen peroxide and monitoring increased labelling of oxidized thiol proteins. A decrease in labelling can also be detected, and this is attributed to the formation of higher oxidation states of cysteine that are not reduced by dithiothreitol.

Self-assembling bubble carriers for oral protein delivery.

Science.gov (United States)

Chuang, Er-Yuan; Lin, Kun-Ju; Lin, Po-Yen; Chen, Hsin-Lung; Wey, Shiaw-Pyng; Mi, Fwu-Long; Hsiao, Hsu-Chan; Chen, Chiung-Tong; Sung, Hsing-Wen

2015-09-01

Successful oral delivery of therapeutic proteins such as insulin can greatly improve the quality of life of patients. This study develops a bubble carrier system by loading diethylene triamine pentaacetic acid (DTPA) dianhydride, a foaming agent (sodium bicarbonate; SBC), a surfactant (sodium dodecyl sulfate; SDS), and a protein drug (insulin) in an enteric-coated gelatin capsule. Following oral administration to diabetic rats, the intestinal fluid that has passed through the gelatin capsule saturates the mixture; concomitantly, DTPA dianhydride produces an acidic environment, while SBC decomposes to form CO2 bubbles at acidic pH. The gas bubbles grow among the surfactant molecules (SDS) owing to the expansion of the generated CO2. The walls of the CO2 bubbles consist of a self-assembled film of water that is in nanoscale and may serve as a colloidal carrier to transport insulin and DTPA. The grown gas bubbles continue to expand until they bump into the wall and burst, releasing their transported insulin, DTPA, and SDS into the mucosal layer. The released DTPA and SDS function as protease inhibitors to protect the insulin molecules as well as absorption enhancers to augment their epithelial permeability and eventual absorption into systemic circulation, exerting their hypoglycemic effects. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis of protons exchange polymeric membranes via co-poly-esters doped with sodium dodecyl sulfate for application in PEM fuel cells; Sintese de membranas polimericas condutoras de protons por imobilizacao de MDs em copoliesteres para aplicacao em PEM-FC

Energy Technology Data Exchange (ETDEWEB)

Fiuza, R.A.; Brioude, M.M.; Bresciani, D.; Jose, N.M.; Boaventura, J.S. [Universidade Federal da Bahia (IQ/UFBA), Salvador, BA (Brazil). Inst. de Quimica

2008-07-01

Polymers are largely studied for use in PEM-type fuel cell (Proton Exchange membrane, PEMFC). These fuel cells are based on polymer membranes as electrolyte, also called protons conductor. This work developed co-polyesters made electrical conductors by doping with sodium dodecyl sulfate. The copolymers were synthesized from the copolymerization of terephthalic and adipic acids with glycerol. The material was processed in a reactor and shaped by hot pressing, yielding homogeneous and flexible plates, with excellent surface finish. The co-polyesters were analyzed by SEM, FTIR, TG, DSC, and XRD. The thermal analysis showed that the composites were thermally stable up to about 250 deg C. The micrographics revealed the MDS homogeneously dispersed in the polymeric matrix. These copolymers showed electrical conductivity between 10-7 to 10-1 S/cm, suggesting strong potential use in PEM fuel cells. (author)

Formation of protein/surfactant adsorption layer at the air/water interface as studied by dilational surface rheology.

Science.gov (United States)

Mikhailovskaya, A A; Noskov, B A; Lin, S-Y; Loglio, G; Miller, R

2011-08-25

The dynamic dilatational surface elasticity of mixed solutions of globular proteins (β-lactoglobulin (BLG) and bovine serum albumin (BSA)) with cationic (dodecyltrimethylammonium bromide (DTAB)) and anionic (sodium dodecyl sulfate (SDS)) surfactants was measured as a function of the surfactant concentration and surface age. If the cationic surfactant concentration exceeds a certain critical value, the kinetic dependencies of the dynamic surface elasticity of BLG/DTAB and BSA/DTAB solutions become nonmonotonous and resemble those of mixed solutions of proteins with guanidine hydrochloride. This result indicates not only the destruction of the protein tertiary structure in the surface layer of mixed solution but also a strong perturbation of the secondary structure. The corresponding kinetic dependencies for protein solutions with added anionic surfactants are always monotonous, thereby revealing a different mechanism of the adsorption layer formation. One can assume that the secondary structure is destroyed to a lesser extent in the latter case and hinders the formation of loops and tails at the interface. The increase of the solution's ionic strength by the addition of sodium chloride results in stronger changes of the protein conformations in the surface layer and the appearance of a local maximum in the kinetic dependencies of the dynamic surface elasticity in a relatively narrow range of SDS concentration. © 2011 American Chemical Society

Electronic Conductivity of Polypyrrole−Dodecyl Benzene Sulfonate Complexes

DEFF Research Database (Denmark)

West, Keld; Bay, Lasse; Nielsen, Martin Meedom

2004-01-01

The electronic conductivity of the electroactive polymer polypyrrole-dodecyl benzene sulfonate (PPy-DBS) has been characterized as function of the redox level. The polymer was synthesized with different isomers of the dopant anions: the common mixed DBS tenside and three well-defined synthetic...

Biochemical and cytological analysis of five cultivars of Cicer ...

African Journals Online (AJOL)

The protein profiling of seed proteins using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) revealed a high polymorphism between the five cultivars. The total number of polypeptide bands recorded was 36, the 4 bands were monomorphic and the rest32 were polymorphic with an average ...

Marker assisted characterization of chickpea genotypes for wilt ...

African Journals Online (AJOL)

Further, the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) analysis of seed storage protein showed a difference in protein profile among studied genotypes but none of polypeptide fragment was specific to wilt resistance or susceptibility. In present study, the reported markers linked to susceptibility ...

Mass spectrometry data from proteomics-based screening of immunoreactive proteins of fully virulent Brucella strains using sera from naturally infected animals

Directory of Open Access Journals (Sweden)

Gamal Wareth

2015-09-01

Full Text Available Here, we provide the dataset associated with our research article on comprehensive screening of Brucella immunoreactive proteins using sera of naturally infected hosts published in Biochemical and Biophysical Research Communications Wareth et al., 2015 [1]. Whole-cell protein extracts were prepared from Brucella abortus and Brucella melitensis, separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE and subsequently western blotting was carried out using sera from bovines (cows and buffaloes and small ruminants (goats and sheep. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org via the PRIDE partner repository [2] with the dataset identifiers PXD001270 and DOI:10.6019/PXD001270.

Mining Protein Evolution for Insights into Mechanisms of Voltage-Dependent Sodium Channel Auxiliary Subunits.

Science.gov (United States)

Molinarolo, Steven; Granata, Daniele; Carnevale, Vincenzo; Ahern, Christopher A

2018-02-21

Voltage-gated sodium channel (VGSC) beta (β) subunits have been called the "overachieving" auxiliary ion channel subunit. Indeed, these subunits regulate the trafficking of the sodium channel complex at the plasma membrane and simultaneously tune the voltage-dependent properties of the pore-forming alpha-subunit. It is now known that VGSC β-subunits are capable of similar modulation of multiple isoforms of related voltage-gated potassium channels, suggesting that their abilities extend into the broader voltage-gated channels. The gene family for these single transmembrane immunoglobulin beta-fold proteins extends well beyond the traditional VGSC β1-β4 subunit designation, with deep roots into the cell adhesion protein family and myelin-related proteins - where inherited mutations result in a myriad of electrical signaling disorders. Yet, very little is known about how VGSC β-subunits support protein trafficking pathways, the basis for their modulation of voltage-dependent gating, and, ultimately, their role in shaping neuronal excitability. An evolutionary approach can be useful in yielding new clues to such functions as it provides an unbiased assessment of protein residues, folds, and functions. An approach is described here which indicates the greater emergence of the modern β-subunits roughly 400 million years ago in the early neurons of Bilateria and bony fish, and the unexpected presence of distant homologues in bacteriophages. Recent structural breakthroughs containing α and β eukaryotic sodium channels containing subunits suggest a novel role for a highly conserved polar contact that occurs within the transmembrane segments. Overall, a mixture of approaches will ultimately advance our understanding of the mechanism for β-subunit interactions with voltage-sensor containing ion channels and membrane proteins.

Maximizing recovery of water-soluble proteins through acetone precipitation.

Science.gov (United States)

Crowell, Andrew M J; Wall, Mark J; Doucette, Alan A

2013-09-24

Solvent precipitation is commonly used to purify protein samples, as seen with the removal of sodium dodecyl sulfate through acetone precipitation. However, in its current practice, protein loss is believed to be an inevitable consequence of acetone precipitation. We herein provide an in depth characterization of protein recovery through acetone precipitation. In 80% acetone, the precipitation efficiency for six of 10 protein standards was poor (ca. ≤15%). Poor recovery was also observed for proteome extracts, including bacterial and mammalian cells. As shown in this work, increasing the ionic strength of the solution dramatically improves the precipitation efficiency of individual proteins, and proteome mixtures (ca. 80-100% yield). This is obtained by including 1-30 mM NaCl, together with acetone (50-80%) which maximizes protein precipitation efficiency. The amount of salt required to restore the recovery correlates with the amount of protein in the sample, as well as the intrinsic protein charge, and the dielectric strength of the solution. This synergistic approach to protein precipitation in acetone with salt is consistent with a model of ion pairing in organic solvent, and establishes an improved method to recover proteins and proteome mixtures in high yield. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis and functioning of the colicin E1 lysis protein: Comparison with the colicin A lysis protein

International Nuclear Information System (INIS)

Cavard, D.

1991-01-01

The colicin E1 lysis protein, CelA, was identified as a 3-kDa protein in induced cells of Escherichia coli K-12 carrying pColE1 by pulse-chase labeling with either [ 35 S]cysteine or [ 3 H]lysine. This 3-kDa protein was acylated, as shown by [2- 3 H]glycerol labeling, and seemed to correspond to the mature CelA protein. The rate of modification and processing of CelA was different from that observed for Cal, the colicin A lysis protein. In contrast to Cal, no intermediate form was detected for CelA, no signal peptide accumulated, and no modified precursor form was observed after globomycin treatment. Thus, the rate of synthesis would not be specific to lysis proteins. Solubilization in sodium dodecyl sulfate of the mature forms of both CelA and Cal varied similarly at the time of colicin release, indicating a change in lysis protein structure. This particular property would play a role in the mechanism of colicin export. The accumulation of the signal peptide seems to be a factor determining the toxicity of the lysis proteins since CelA provoked less cell damage than Cal. Quasi-lysis and killing due to CelA were higher in degP mutants than in wild-type cells. They were minimal in pldA mutants

sodium dodecyl sulphate (SDS)

Indian Academy of Sciences (India)

Unknown

In contrast, much higher concentration of NaCl (2 M) is required for the salting-out effect of the dye–surfactant complex for conversion to the micellized form. Keywords. Cresyl violet; surfactant; salt effect; absorption; stopped-flow. 1. Introduction. Cresyl violet, a cationic dye (CV+, scheme 1) belonging to the phenoxazine ...

E3 protein of bovine coronavirus is a receptor-destroying enzyme with acetylesterase activity

International Nuclear Information System (INIS)

Vlasak, R.; Luytjes, W.; Leider, J.; Spaan, W.; Palese, P.

1988-01-01

In addition to members of the Orthomyxoviridae and Paramyxoviridae, several coronaviruses have been shown to possess receptor-destroying activities. Purified bovine coronavirus (BCV) preparations have an esterase activity which inactivates O-acetylsialic acid-containing receptors on erythrocytes. Diisopropyl fluorophosphate (DFP) completely inhibits this receptor-destroying activity of BCV, suggesting that the viral enzyme is a serine esterase. Treatment of purified BCV with [ 3 H]DFP and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the proteins revealed that the esterase/receptor-destroying activity of BCV is associated with the E3 protein was specifically phosphorylated. This finding suggests that the esterase/receptor-destroying activity of BCV is associated with the E3 protein. Furthermore, treatment of BCV with DFP dramatically reduced its infectivity in a plaque assay. It is assumed that the esterase activity of BCV is required in an early step of virus replication, possible during virus entry or uncoating

Influence of puerperium on the serum proteins of Saanen goats, obtained by the analysis of electrophoresis on sodium dodecyl sulphate-polyacrylamide gel / Influência do puerpério sobre o proteinograma sérico de caprinos da raça Saanen obtido por eletroforese em gel de poliacrilamida

Directory of Open Access Journals (Sweden)

Eduardo Harry Birgel Junior

2009-10-01

Full Text Available Aiming to evaluate the puerperal influence on the proteinogram of Saanen goats, 108 samples of blood serum from 12 goats were collected, and the results were presented at nine times: just after parturition, 1, 3, 5, 7, 10, 15, 21 and 30 days after parturition. Total amount of serum proteins were determined by the biuret technique, and the sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE was used to the protein fractionation. In this last method, 17 protein bands were observed, from which molecular weights varied between 25 KDa and 275 KDa. In addition, it was possible to identify the following protein fractions: immunoglobulin A (180 KDa, ceruloplasmin (115 KDa, transferrin (79 KDa, albumin (65 KDa, heavy-chain immunoglobulin G (58 KDa, haptoglobin (45 KDa, acid glycoprotein (37 KDa and light-chain immunoglobulin G (28 KDa. Another 9 nonidentified protein fractions presented, each molecular weights equal to 275 KDa, 140 KDa, 125 KDa, 103 KDa, 95 KDa, 41 KDa, 35 KDa, 30 Kda and 25 KDa. The results allow us to conclude that by the first week of puerperium, an improvement of acid glycoprotein occurs, whereas those others protein fractions do not suffer any puerperal influence.Com o objetivo de avaliar a influência do puerpério no proteinograma de caprinos da raça Saanen foram colhidas 108 amostras de soro sangüíneo de 12 cabras, sendo os resultados apresentados em nove momentos: imediatamente após a parição, 1, 3, 5, 7, 10, 15, 21 e 30 dias após o parto. Os teores séricos de proteína total foram determinados pela técnica do biureto, e para o fracionamento das proteínas foi realizada a eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE. No método utilizado foram observadas 17 bandas protéicas, cujos pesos moleculares (PM variaram de 25 KDa a 275 KDa, sendo possível a identificação das seguintes frações protéicas: imunoglobulina A (180 KDa, ceruloplasmina (115 KDa, transferrina

Influence of Microheterogeneous Environments of Sodium Dodecyl Sulfate on the Kinetics of Oxidation of l-Serine by Chloro and Chlorohydroxo Complexes of Gold(III).

Science.gov (United States)

Maiti, Krishnendu; Sen, Pratik K; Barik, Anil K; Pal, Biswajit

2018-06-21

The oxidation of l-serine by chloro and chlorohydroxo complexes of gold(III) was spectrophotometrically investigated in acidic buffer media in the absence and presence of the anionic surfactant sodium dodecyl sulfate (SDS). The oxidation rate decreases with increase in either [H + ] or [Cl - ]. Gold(III) complex species react with the zwitterionic form of serine to yield acetaldehyde (principal reaction product) through oxidative decarboxylation and subsequent deamination processes. A reaction pathway involving one electron transfer from serine to Au(III) followed by homolytic cleavage of α-C-C bond with the concomitant formation of iminic cation intermediate has been proposed where Au(III) is initially reduced to Au(II). The surfactant in the submicellar region exhibits a catalytic effect on the reaction rate at [SDS] ≤ 4 mM; however, in the postmicellar region an inhibitory effect was prominent at [SDS] ≥ 4 mM. The catalytic effect below the critical micelle concentration (cmc) may be attributable to the electrostatic attraction between serine and SDS that, in turn, enhances the nucleophilicity of the carboxylate ion of the amino acid. The inhibition effect beyond cmc has been explained by considering the distribution of the reactant species between the aqueous and the micellar pseudophases that restricts the close association of the reactant species. The thermodynamic parameters Δ H 0 and Δ S 0 associated with the binding between serine and SDS micelle were calculated to be -14.4 ± 2 kJ mol -1 and -6.3 ± 0.5 J K -1 mol -1 , respectively. Water structure rearrangement and micelle-substrate binding play instrumental roles during the transfer of the reactant species from aqueous to micellar pseudophase.

Generation and stabilization of whey-based monodisperse naoemulsions using ultra-high pressure homogenization and small amphipathic co-emulsifier combinations

Science.gov (United States)

Ultra-high-pressure homogenization (UHPH) was used to generate monodisperse stable peanut oil nanoemulsions within a desired nanosize range (whey protein concentrate (WPC), sodium dodecyl sulfate, Triton X-100 (X100), and zwitterionic sulfobetaine-base...

Effects of surface proteins and lipids on molecular structure, thermal properties, and enzymatic hydrolysis of rice starch

Directory of Open Access Journals (Sweden)

Pan HU

Full Text Available Abstract Rice starches with different amylose contents were treated with sodium dodecyl sulfate (SDS to deplete surface proteins and lipids, and the changes in molecular structure, thermal properties, and enzymatic hydrolysis were evaluated. SDS treatment did not significantly change the molecular weight distribution, crystalline structure, short-range ordered degree, and gelatinization properties of starch, but significantly altered the pasting properties and increased the swelling power of starch. The removal of surface proteins and lipids increased the enzymatic hydrolysis and in vitro digestion of starch. The influences of removing surface proteins and lipids from starch on swelling power, pasting properties, and enzymatic hydrolysis were different among the various starches because of the differences in molecular structures of different starch styles. The aforementioned results indicated that removing the surface proteins and lipids from starch did not change the molecular structure but had significant effects on some functional properties.

A practical method for extending the biuret assay to protein determination of corn-based products.

Science.gov (United States)

Liu, Zelong; Pan, Junhui

2017-06-01

A modified biuret method suitable for protein determination of corn-based products was developed by introducing a combination of an alkaline reagent with sodium dodecyl sulfate (reagent A) and heat treatments. The method was tested on seven corn-based samples. The results showed mostly good agreement (P>0.05) as compared to the Kjeldahl values. The proposed method was found to enhance the accuracy of prediction on zein content using bovine serum albumin as standard. Reagent A and sample treatment were proved to effectively improve protein solubilization for the thermally-dried corn-based products, e.g. corn gluten meal. The absorbance was stable for at least 1-h. Moreover, the whole measurement of protein content only needs 15-20min more than the traditional biuret assay, and can be performed in batches. The findings suggest that the proposed method could be a timesaving alternative for routine protein analyses in corn processing factories. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis of acid-soluble spore proteins by Bacillus subtilis.

Science.gov (United States)

Leventhal, J M; Chambliss, G H

1982-12-01

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

高职精细化工实验--十二烷基硫酸钠的制备1例%Recommendation of a fine chemical experiment-the synthesis of sodium dodecyl sulfate

Institute of Scientific and Technical Information of China (English)

张桂锋

2014-01-01

在教学实践的基础上，推荐一个适合高职院校精细化工专业学生的实验---十二烷基硫酸钠的制备。以浓硫酸和尿素为催化剂，用月桂醇(正十二醇)和氨基磺酸反应，然后加入氢氧化钠放尽氨气，所得粗产物，经提纯、干燥精制得白色或淡黄色固体。通过实验可以让学生掌握硫酸化制备阴离子表面活性剂的基本原理和方法，并掌握尾气吸收、提纯等精细化工实验操作技能。%Based on the teaching practice, a fine chemical experiments was recommend, it's suitable for advanced vocational students———the synthesis of sodium dodecyl sulfate. Using sulfuric acid and urea as catalyst, lauryl alcohol ( lauryl alcohol) and amino sulfonic acid were reacted, and sodium hydroxide was put ammonia, so the coarse product was gotten, and then, the white or light yellow solid were obtained by purification and drying. Through the experiment can make the students master the basic principle of sulfating preparation of anionic surfactant and methods, and grasp the experimental operation skills of fine chemical industry, such as the tail gas absorption and purification .

The dual effects of Maillard reaction and enzymatic hydrolysis on the antioxidant activity of milk proteins.

Science.gov (United States)

Oh, N S; Lee, H A; Lee, J Y; Joung, J Y; Lee, K B; Kim, Y; Lee, K W; Kim, S H

2013-08-01

The objective of this study was to determine the enhanced effects on the biological characteristics and antioxidant activity of milk proteins by the combination of the Maillard reaction and enzymatic hydrolysis. Maillard reaction products were obtained from milk protein preparations, such as whey protein concentrates and sodium caseinate with lactose, by heating at 55°C for 7 d in sodium phosphate buffer (pH 7.4). The Maillard reaction products, along with untreated milk proteins as controls, were hydrolyzed for 0 to 3h with commercial proteases Alcalase, Neutrase, Protamex, and Flavorzyme (Novozymes, Bagsværd, Denmark). The antioxidant activity of hydrolyzed Maillard reaction products was determined by reaction with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, their 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and the ability to reduce ferric ions. Further characteristics were evaluated by the o-phthaldialdehyde method and sodium dodecyl sulfate-PAGE. The degree of hydrolysis gradually increased in a time-dependent manner, with the Alcalase-treated Maillard reaction products being the most highly hydrolyzed. Radical scavenging activities and reducing ability of hydrolyzed Maillard reaction products increased with increasing hydrolysis time. The combined products of enzymatic hydrolysis and Maillard reaction showed significantly greater antioxidant activity than did hydrolysates or Maillard reaction products alone. The hydrolyzed Maillard reaction products generated by Alcalase showed significantly higher antioxidant activity when compared with the other protease products and the antioxidant activity was higher for the whey protein concentrate groups than for the sodium caseinate groups. These findings indicate that Maillard reaction products, coupled with enzymatic hydrolysis, could act as potential antioxidants in the pharmaceutical, food, and dairy industries. Copyright © 2013 American Dairy Science Association

Reusable hydroxyapatite nanocrystal sensors for protein adsorption

International Nuclear Information System (INIS)

Tagaya, Motohiro; Ikoma, Toshiyuki; Hanagata, Nobutaka; Chakarov, Dinko; Kasemo, Bengt; Tanaka, Junzo

2010-01-01

The repeatability of the adsorption and removal of fibrinogen and fetal bovine serum on hydroxyapatite (HAp) nanocrystal sensors was investigated by Fourier transform infrared (FTIR) spectroscopy and quartz crystal microbalance with dissipation (QCM-D) monitoring technique. The HAp nanocrystals were coated on a gold-coated quartz sensor by electrophoretic deposition. Proteins adsorbed on the HAp sensors were removed by (i) ammonia/hydrogen peroxide mixture (APM), (ii) ultraviolet light (UV), (iii) UV/APM, (iv) APM/UV and (v) sodium dodecyl sulfate (SDS) treatments. FTIR spectra of the reused surfaces revealed that the APM and SDS treatments left peptide fragments or the proteins adsorbed on the surfaces, whereas the other methods successfully removed the proteins. The QCM-D measurements indicated that in the removal treatments, fibrinogen was slowly adsorbed in the first cycle because of the change in surface wettability revealed by contact angle measurements. The SDS treatment was not effective in removing proteins. The APM or UV treatment decreased the frequency shifts for the reused HAp sensors. The UV/APM treatment did not induce the frequency shifts but decreased the dissipation shifts. Therefore, we conclude that the APM/UV treatment is the most useful method for reproducing protein adsorption behavior on HAp sensors.

Reusable hydroxyapatite nanocrystal sensors for protein adsorption

Directory of Open Access Journals (Sweden)

Motohiro Tagaya, Toshiyuki Ikoma, Nobutaka Hanagata, Dinko Chakarov, Bengt Kasemo and Junzo Tanaka

2010-01-01

Full Text Available The repeatability of the adsorption and removal of fibrinogen and fetal bovine serum on hydroxyapatite (HAp nanocrystal sensors was investigated by Fourier transform infrared (FTIR spectroscopy and quartz crystal microbalance with dissipation (QCM-D monitoring technique. The HAp nanocrystals were coated on a gold-coated quartz sensor by electrophoretic deposition. Proteins adsorbed on the HAp sensors were removed by (i ammonia/hydrogen peroxide mixture (APM, (ii ultraviolet light (UV, (iii UV/APM, (iv APM/UV and (v sodium dodecyl sulfate (SDS treatments. FTIR spectra of the reused surfaces revealed that the APM and SDS treatments left peptide fragments or the proteins adsorbed on the surfaces, whereas the other methods successfully removed the proteins. The QCM-D measurements indicated that in the removal treatments, fibrinogen was slowly adsorbed in the first cycle because of the change in surface wettability revealed by contact angle measurements. The SDS treatment was not effective in removing proteins. The APM or UV treatment decreased the frequency shifts for the reused HAp sensors. The UV/APM treatment did not induce the frequency shifts but decreased the dissipation shifts. Therefore, we conclude that the APM/UV treatment is the most useful method for reproducing protein adsorption behavior on HAp sensors.

Characterization of the corrinoid iron-sulfur protein tetrachloroethene reductive dehalogenase of Dehalobacter restrictus

NARCIS (Netherlands)

Maillard, J.; Schumacher, W.; Vazquez, F.; Regeard, C.; Hagen, W.R.; Holliger, C.

2003-01-01

The membrane-bound tetrachloroethene reductive dehalogenase (PCE-RDase) (PceA; EC 1.97.1.8), the terminal component of the respiratory chain of Dehalobacter restrictus, was purified 25-fold to apparent electrophoretic homogeneity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a

Ras p21 and other Gn proteins are detected in mammalian cell lines by [gamma-35S]GTP gamma S binding

International Nuclear Information System (INIS)

Comerford, J.G.; Gibson, J.R.; Dawson, A.P.; Gibson, I.

1989-01-01

The presence of guanine nucleotide binding proteins in mouse and human cell lines was investigated using [gamma- 35 S]GTP gamma S and [gamma-32P]GTP. Cell lysate polypeptides were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis and transferred to nitrocellulose. Incubation of the nitrocellulose blots with [gamma- 35 S]GTP gamma S identified 9 distinct GTP-binding polypeptides in all lysates. One of these is the ras oncogene product, p21, as demonstrated by subsequent immunochemical staining of the nitrocellulose blots. We have shown that this procedure provides a sensitive method for detection of p21 in culture cell lines

Proteomic study of muscle sarcoplasmic proteins using AUT-PAGE/SDS-PAGE as two-dimensional gel electrophoresis.

Science.gov (United States)

Picariello, Gianluca; De Martino, Alessandra; Mamone, Gianfranco; Ferranti, Pasquale; Addeo, Francesco; Faccia, Michele; Spagnamusso, Salvatore; Di Luccia, Aldo

2006-03-20

In the present study, an alternative procedure for two-dimensional (2D) electrophoretic analysis in proteomic investigation of the most represented basic muscle water-soluble proteins is suggested. Our method consists of Acetic acid-Urea-Triton polyacrylamide gel (AUT-PAGE) analysis in the first dimension and standard sodium dodecyl sulphate polyacrylamide gel (SDS-PAGE) in the second dimension. Although standard two-dimensional Immobilized pH Gradient-Sodium Dodecyl-Sulphate (2D IPG-SDS) gel electrophoresis has been successfully used to study these proteins, most of the water-soluble proteins are spread on the alkaline part of the 2D map and are poorly focused. Furthermore, the similarity in their molecular weights impairs resolution of the classical approach. The addition of Triton X-100, a non-ionic detergent, into the gel induces a differential electrophoretic mobility of proteins as a result of the formation of mixed micelles between the detergent and the hydrophobic moieties of polypeptides, separating basic proteins with a criterion similar to reversed phase chromatography based on their hydrophobicity. The acid pH induces positive net charges, increasing with the isoelectric point of proteins, thus allowing enhanced resolution in the separation. By using 2D AUT-PAGE/SDS electrophoresis approach to separate water-soluble proteins from fresh pork and from dry-cured products, we could spread proteins over a greater area, achieving a greater resolution than that obtained by IPG in the pH range 3-10 and 6-11. Sarcoplasmic proteins undergoing proteolysis during the ripening of products were identified by Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI-ToF) mass spectrometry peptide mass fingerprinting in a easier and more effective way. Two-dimensional AUT-PAGE/SDS electrophoresis has allowed to simplify separation of sarcoplasmic protein mixtures making this technique suitable in the defining of quality of dry-cured pork products by immediate

Analytical purification of a 60-kDa target protein of artemisinin detected in Trypanosoma brucei brucei

Directory of Open Access Journals (Sweden)

Benetode Konziase

2015-12-01

Full Text Available Here we describe the isolation and purity determination of Trypanosoma brucei (T. b. brucei candidate target proteins of artemisinin. The candidate target proteins were detected and purified from their biological source (T. b. brucei lysate using the diazirine-free biotinylated probe 5 for an affinity binding to a streptavidin-tagged resin and, subsequently, the labeled target proteins were purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. We herein showed the electrophoresis gel and the immunoblotting film containing the 60-kDa trypanosomal candidate target protein of artemisinin as a single band, which was visualized on-gel by the reverse-staining method and on a Western blotting film by enhanced chemiluminescence. The data provided in this article are related to the original research article “Biotinylated probes of artemisinin with labeling affinity toward Trypanosoma brucei brucei target proteins”, by Konziase (Anal. Biochem., vol. 482, 2015, pp. 25–31. http://dx.doi.org/10.1016/j.ab.2015.04.020.

Highly increased detection of silver stained protein bands in polyacrylamide gels with thermo-optical methods

Science.gov (United States)

Mazza, Giulia; Posnicek, Thomas; Brandl, Martin

2016-11-01

Sodium dodecyl sulfate polyacrylamide gel electrophoresis is a well-known technique to separate proteins by their molecular weight. After electrophoresis, the gels are commonly stained for protein band analysis with silver stain; this allows the detection of protein loads to about 1 ng. To increase the detection sensitivity of the protein bands down in the subnanogram level, a sensor has been developed based on the thermal lens effect to scan and quantify protein loads which would remain undetected using the standard imaging systems. The thermal lens sensor is equipped with a 450 nm diode pump laser modulated at 1 Hz and a HeNe probe laser mounted in collinear geometry. The sensor could detect protein bands of 0.05 ng when the gel was soaked in methanol/water and 0.1 ng in water. The limit of detection ranged from 8 to 20 pg, depending on the soaking medium and the staining efficiency. Thus, the detection of silver stain by thermal lens effect results 10 to 20 times more sensitive than the standard colorimetric method.

Extraction methods and test techniques for detection of vegetable proteins in meat products. I. Qualitative detection of soya derivatives.

Science.gov (United States)

Hyslop, N S

1976-06-01

Extracts of 3 soya bean preparations, used commercially in certain countries to replace part of the meat in popular meat products, were made by treatment with (i) sodium dodecyl sulphate, (ii) Triton-X100 or (iii) n-Butanol. Similar extracts were made from beef and pork. All extracts were examined by electrophoretic and immunological techniques. Stained polyacrylamide gels revealed distinctive protein bands after electrophoresis. The migration rates of corresponding bands differed between beef and pork extracts. However, the migration rates of vegetable bands revealed certain similarities, but differed very greatly from those of animal origin. Characteristic fast-migrating S-bands were distinguishable only in extracts of vegetable protein. Immunodiffusion tests, using antisera produced in rabbits against each extract, revealed varying degrees of similarity between extracts of vegetable origin, but the antisera were specific for either vegetable or animal protein.

Fluorometric determination of proteins using the yttrium(III)-sodium lauryl sulfate-rutin-protein system

International Nuclear Information System (INIS)

Liu Shufang; Yang Jinghe; Wu Xia; Wang Fei; Wang Feng; Jia Zhen

2006-01-01

It is found that rutin can react with yttrium(III) (Y 3+ ), and emits fluorescence of rutin. The intensity is greatly enhanced by proteins in the presence of sodium lauryl sulfate (SLS). Based on this, a new fluorimetric method of determination of proteins is developed. Under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of proteins in the range of 5.0x10 -9 -1.0x10 -5 g/mL for bovine serum albumin (BSA), 3.0x10 -8 -1.0x10 -5 g/mL for human serum albumin (HSA) and 1.0x10 -7 -2.0x10 -5 g/mL for egg albumin (EA). Their detection limits (S/N=3) are 1.6x10 -9 , 9.8x10 -9 and 2.1x10 -8 g/mL, respectively. The interaction mechanism is also studied

Fluorometric determination of proteins using the yttrium(III)-sodium lauryl sulfate-rutin-protein system

Energy Technology Data Exchange (ETDEWEB)

Liu Shufang [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Yang Jinghe [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)]. E-mail: yjh@sdu.edu.cn; Wu Xia [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang Fei [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang Feng [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Jia Zhen [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

2006-04-15

It is found that rutin can react with yttrium(III) (Y{sup 3+}), and emits fluorescence of rutin. The intensity is greatly enhanced by proteins in the presence of sodium lauryl sulfate (SLS). Based on this, a new fluorimetric method of determination of proteins is developed. Under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of proteins in the range of 5.0x10{sup -9}-1.0x10{sup -5}g/mL for bovine serum albumin (BSA), 3.0x10{sup -8}-1.0x10{sup -5}g/mL for human serum albumin (HSA) and 1.0x10{sup -7}-2.0x10{sup -5}g/mL for egg albumin (EA). Their detection limits (S/N=3) are 1.6x10{sup -9}, 9.8x10{sup -9} and 2.1x10{sup -8}g/mL, respectively. The interaction mechanism is also studied.

Physiochemical, texture properties, and the microstructure of set yogurt using whey protein-sodium tripolyphosphate aggregates as thickening agents.

Science.gov (United States)

Cheng, Jianjun; Xie, Siyu; Yin, Yuan; Feng, Xianmin; Wang, Shuai; Guo, Mingruo; Ni, Chunlei

2017-07-01

Polymerized whey protein-sodium tripolyphosphate can be induced to gel in an acidic environment provided during fermentation. The variety of thickening agent has an influence on texture that is an essential aspect of yogurt quality affecting consumer preference. Similar to polysaccharide stabilizers, the cold gelation properties of whey proteins can improve the body texture of yogurt products. Polymerized whey protein-sodium tripolyphosphate could be a favorable and interesting thickening agent for making set yogurt. The effects of whey protein isolate (WPI), heat-treated whey protein-sodium tripolyphosphate (WPI-STPP), heat-treated WPI and pectin on the storage properties and microstructure of yogurt were investigated. All samples were analyzed for syneresis, pH, titratable acidity, viscosity, texture profile and microstructure during storage. The results showed that incorporating heat-treated WPI-STPP had a significant impact on syneresis (32.22 ± 0.60), viscosity (10 956.67 ± 962.1) and hardness (209.24 ± 12.48) (p Yogurt fermented with modified WPI-STPP had higher levels of protein and better hardness compared with yogurt using pectin. The microstructure was observed to be a uniform and denser, complicated network. Heat-treated WPI-STPP may be useful for improving yogurt texture. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

E3 protein of bovine coronavirus is a receptor-destroying enzyme with acetylesterase activity

Energy Technology Data Exchange (ETDEWEB)

Vlasak, R.; Luytjes, W.; Leider, J.; Spaan, W.; Palese, P.

1988-12-01

In addition to members of the Orthomyxoviridae and Paramyxoviridae, several coronaviruses have been shown to possess receptor-destroying activities. Purified bovine coronavirus (BCV) preparations have an esterase activity which inactivates O-acetylsialic acid-containing receptors on erythrocytes. Diisopropyl fluorophosphate (DFP) completely inhibits this receptor-destroying activity of BCV, suggesting that the viral enzyme is a serine esterase. Treatment of purified BCV with (/sup 3/H)DFP and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the proteins revealed that the esterase/receptor-destroying activity of BCV is associated with the E3 protein was specifically phosphorylated. This finding suggests that the esterase/receptor-destroying activity of BCV is associated with the E3 protein. Furthermore, treatment of BCV with DFP dramatically reduced its infectivity in a plaque assay. It is assumed that the esterase activity of BCV is required in an early step of virus replication, possible during virus entry or uncoating.

Morphologic identification and proteomic analysis in adult ...

African Journals Online (AJOL)

In gel separation of the resulting supernatant was achieved using1 dimesnsional Sodium dodecyl sulfate polyacrylamide gel electrophoresis (1DE SDS-PAGE). The raw images of the gel were captured using and analyses on 1D Totallabsoft ware. The software identified 7 (seven) protein bands for male and 10 (ten) protein ...

Synthesis of P-protein in mature phloem of Cucurbita maxima.

Science.gov (United States)

Nuske, J; Eschrich, W

1976-01-01

Cotyledons of Cucurbita maxima Duch. seedlings were provided with (14)C-labeled amino acids for 12 h. Besides the bulk of labeled amino acids the sieve-tube exudate also carried labeled proteins. 80% of the incorporated radioactivity was found in the P-protein, 20% in a neutral protein, and traces were found in acidic proteins after fractionation on diethyl-aminoethyl cellulose columns. The radioactive elutes were characterized by autoradiographs of both disc- and sodium dodecyl sulfate-gelelectropherograms, and by isoelectric focusing. The P-protein fraction appeared with the void volume from the diethylaminoethyl-cellulose column. Obviously, this is the protein that gels when oxidized and that is reversibly precipitable giving rise to filaments when processed for electron microscopy. Its main component has a molecular weight of 115,000 Dalton. By isoelectric focusing this fraction separated into 3 proteins with isoelectric points of 9.8, 9.4, and 9.2. The isoelectric point 9.2-protein probably is identical with an oligomer of a 30,000 Dalton protein with neutral isoelectric point, which keeps 20% of the incorporated label. Microautoradiographs suggest that the labeled proteins were synthesized in companion cells. The results indicate that P-protein of Cucurbita maxima is synthesized continuously in mature phloem. It can be assumed that P-protein has a relatively high turn-over rate. Therefore it seems unlikely that P-protein is a "structural" protein.

Self-Assembling Peptide Surfactants A6K and A6D Adopt a-Helical Structures Useful for Membrane Protein Stabilization

Directory of Open Access Journals (Sweden)

Furen Zhuang

2011-10-01

Full Text Available Elucidation of membrane protein structures have been greatly hampered by difficulties in producing adequately large quantities of the functional protein and stabilizing them. A6D and A6K are promising solutions to the problem and have recently been used for the rapid production of membrane-bound G protein-coupled receptors (GPCRs. We propose that despite their short lengths, these peptides can adopt α-helical structures through interactions with micelles formed by the peptides themselves. These α-helices are then able to stabilize α-helical motifs which many membrane proteins contain. We also show that A6D and A6K can form β-sheets and appear as weak hydrogels at sufficiently high concentrations. Furthermore, A6D and A6K together in sodium dodecyl sulfate (SDS can form expected β-sheet structures via a surprising α-helical intermediate.

Influence of secretagogues on asynchronous secretion of newly synthesized pancreatic proteins in the conscious rat

International Nuclear Information System (INIS)

Keim, V.; Rohr, G.

1987-01-01

The secretion of newly synthesized pancreatic enzymes was studied in pancreatic duct cannulated rats after intravenous injection of 100 microCi of [ 35 S]methionine. Secretion rate was stimulated by intravenous infusion of either cerulein (0.2 microgram/kg h) or carbachol (10 nmol/kg h) starting simultaneously with or 180 min before the injection of the labeled methionine. Secretory proteins were analyzed by sodium dodecyl sulfate (SDS) gel electrophoresis or by nondenaturing gel electrophoresis followed by determination of the radioactivity associated with the individual proteins. Similar to unstimulated controls in all experiments, an early secretion of newly synthesized trypsinogen and chymotrypsinogen was found, whereas amylase and lipase were secreted only after a certain lag period. The results suggest that the intracellular transit of endoproteases is faster than that of other enzymes, irrespective of whether or not secretagogues were applied

Western blotting of high and low molecular weight proteins using heat.

Science.gov (United States)

Kurien, Biji T; Scofield, R Hal

2015-01-01

A method for the electrophoretic transfer of high and low molecular weight proteins to nitrocellulose membranes following sodium dodecyl sulfate (SDS) polyacrylamide gel is described here. The transfer was performed with heated (70-75 °C) normal transfer buffer from which methanol had been omitted. Complete transfer of high and low molecular weight antigens (molecular weight protein standards, a purified protein, and proteins from a human tissue extract) could be carried out in 10 min for a 7 % (0.75 mm) SDS polyacrylamide gel. For 10 and 12.5 % gels (0.75 mm) the corresponding time was 15 min. A complete transfer could be carried out in 20 min for 7, 10, and 12.5 % gels (1.5 mm gels). The permeability of the gel is increased by heat, such that the proteins trapped in the polyacrylamide gel matrix can be easily transferred to the membrane. The heat mediated transfer method was compared with a conventional transfer protocol, under similar conditions. The conventional method transferred minimal low molecular weight proteins while retaining most of the high molecular weight proteins in the gel. In summary, this procedure is particularly useful for the transfer of high molecular weight proteins, very rapid, and avoids the use of methanol.

Immunochemical and biological characterization of outer membrane proteins of Porphyromonas endodontalis.

Science.gov (United States)

Ogawa, T; Kuribayashi, S; Shimauchi, H; Toda, T; Hamada, S

1992-01-01

Outer membrane proteins (OMP) of Porphyromonas endodontalis HG 370 (ATCC 35406) were prepared from the cell envelope fraction of the organisms. The cell envelope that had been obtained by sonication of the whole cells was extracted in 2% lithium dodecyl sulfate and then successively chromatographed with Sephacryl S-200 HR and DEAE-Sepharose Fast Flow. Two OMP fractions, OMP-I and OMP-II, were obtained, and their immunochemical properties and induction of specific antibodies were examined. The OMP-I preparation consisted of a major protein with an apparent molecular mass of 31 kDa and other moderate to minor proteins of 40.3, 51.4, 67, and 71.6 kDa, while the OMP-II preparation contained 14-, 15.5-, 27-, and 44-kDa proteins as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis. OMP-I was found to form hydrophilic diffusion pores by incorporation into artificial liposomes composed of egg yolk phosphatidylcholine and dicetylphosphate, indicating that OMP-I exhibited significant porin activity. However, the liposomes containing heat-denatured OMP-I were scarcely active. Spontaneous and antigen-specific immunoglobulin M (IgM)-, IgG-, and IgA-secreting spot-forming cells (SFC) enzymatically dissociated into single-cell suspensions from chronically inflamed periapical tissues and were enumerated by enzyme-linked immunospot assay. In patients with radicular cysts or dental granulomas, the major isotype of spontaneous SFC was IgG. In radicular cysts, the OMP-II-specific IgG SFC represented 0.13% of the total IgG SFC, while the antigen-specific IgA or IgM SFC was not observed. It was also found that none of these mononuclear cells produced antibodies specific for OMP-I or lipopolysaccharide of P. endodontalis. Images PMID:1328059

Change of the structure and the digestibility of myofibrillar proteins in Nanjing dry-cured duck during processing.

Science.gov (United States)

Du, Xiaojing; Sun, Yangying; Pan, Daodong; Wang, Ying; Ou, Changrong; Cao, Jinxuan

2018-06-01

To investigate the change of bioavailability and structure of myofibrillar proteins during Nanjing dry-cured duck processing, carbonyl content, sulfhydryl (SH) group, disulfide (SS) group, sodium dodecyl sulfate polyacrylamide gel electrophoresis, surface hydrophobicity, secondary structures and in vitro digestibility were determined. During processing, carbonyl content and surface hydrophobicity increased; SH turned into SS group; α-helix turned into β-sheet and random coil fractions. Protein degradation occurred during dry-curing and drying-ripening stages. The in vitro digestibility of pepsin and pancreatic proteases increased during the salt curing stage and decreased during the drying-ripening stage. The increase of digestibility could be attributed to the mild oxidation, degradation and unfolding of proteins while the decrease of digestibility was related to the intensive oxidation and aggregation of proteins. Protein degradation was not a main factor of digestibility during the drying-ripening stage. Results demonstrated that the bioavailability loss of myofibrillar proteins in Nanjing dry-cured duck occurred during the stage of drying-ripening instead of curing. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Optimization of protein extraction process from jackfruit seed flour by reverse micelle system

Directory of Open Access Journals (Sweden)

Maycon Fagundes Teixeira Reis

2016-06-01

Full Text Available The extraction of protein from flour of jackfruit seeds by reverse micelles was evaluated. Reverse micelle system was composed of sodium dodecyl sulfate (SDS as surfactant, butanol as solvent, and water. The effects of stirring time, temperature, molar ratio H2O SDS-1, concentration of butanol (mass percentage and flour mass were tested in batch systems. Based on the adjusted linear regression model, only butanol concentration provided optimum extraction conditions (41.16%. Based on the analysis of surface response, the best extraction yield could be obtained at 25°C, stirring time of 120 min, mass of flour of 100 mg, and a ratio H2O SDS-1 of 50. Experimental results showed that a 79.00% extraction yield could be obtained.

Purification and characterization of xylanase from Aspergillus ...

African Journals Online (AJOL)

Xylanase was subjected to a three-step purification scheme involving ammonium sulphate precipitation, gel filtration chromatography and anion exchange chromatography. Purity was verified by running the extracted protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and a single band was ...

A model for the molecular structure of the glutenins from wheat flour

NARCIS (Netherlands)

Graveland, A.; Bosveld, P.; Lichtendonk, W.J.; Marseille, J.P.; Moonen, J.H.E.; Scheepstra, A.

1985-01-01

Protein fractions, which were termed glutenins I, IIa, IIb, IIIa and IIIb were isolated from flour of the Dutch wheat cultivar, Sicco, by extraction with sodium dodecyl sulphate (SDS) solution and fractionation by precipitation/redissolution techniques and by gel filtration chromatography. The

Lipase and phospholipase activities of Hymenoptera venoms ...

African Journals Online (AJOL)

native gel), Polistes flavis venom has four major protein bands, one of which has lipase activity; with sodium dodecyl sulfate (SDS-PAGE), the venom had eighteen bands with molecular weights ranging from a maximum of 94 kD and a minimum of ...

Mixed Hemi/Ad-Micelle Sodium Dodecyl Sulfate-Coated Magnetic Iron Oxide Nanoparticles for the Efficient Removal and Trace Determination of Rhodamine-B and Rhodamine-6G.

Science.gov (United States)

Ranjbari, Elias; Hadjmohammadi, Mohammad Reza; Kiekens, Filip; De Wael, Karolien

2015-08-04

Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g(-1), respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L(-1) of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL(-1). Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples.

Selective Protein Extraction from Chlorobium tepidum Chlorosomes Using Detergents. Evidence That CsmA Forms Multimers and Binds Bacteriochlorophyll a

DEFF Research Database (Denmark)

Bryant, Donald A; Vassilieva, Elena V; Frigaard, Niels-Ulrik

2002-01-01

and location of this BChl a are not yet clearly understood. Chlorosomes were treated with sodium dodecyl sulfate (SDS), Lubrol PX, or Triton X-100, separately or in combination with 1-hexanol, and the extracted components were separated from the residual chlorosomes by ultrafiltration on centrifugal filters....... When chlorosomes were treated with low concentrations of SDS, all proteins except CsmA were extracted. However, this treatment did not significantly alter the size and shape of the chlorosomes, did not extract the BChl a, and caused only minor changes in the absorption spectrum of the chlorosomes....... Cross-linking studies with SDS-treated chlorosomes revealed the presence of multimers of the major chlorosome protein, CsmA, up to homooctamers. Extraction of chlorosomes with SDS and 1-hexanol solubilized all ten chlorosome envelope proteins as well as BChl a. Although the size and shape...

Binding protein for vitamin D and its metabolites in rat mesenteric lymph

International Nuclear Information System (INIS)

Dueland, S.; Bouillon, R.; Van Baelen, H.; Pedersen, J.I.; Helgerud, P.; Drevon, C.A.

1985-01-01

A protein with high affinity for vitamin D3 and 25-hydroxyvitamin D3 in rat mesenteric lymph has been studied. Mesenteric lymph was collected after duodenal instillation of radiolabeled vitamin D3 and 25-hydroxyvitamin D3. As previously described, approximately 10% of vitamin D3 and 95% of 25-hydroxyvitamin D3 recovered in mesenteric lymph were associated with the alpha-globulin fractions. The radioactive vitamin D3 recovered in the lymph fraction with d greater than 1.006 (free of chylomicrons) coeluted with purified rat serum binding protein for vitamin D and its metabolites (DBP) from an antirat DBP column. The results obtained by immunoblotting after sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that this protein in mesenteric lymph had molecular weight and immunological properties identical with purified serum DBP. Purified serum DBP labeled with 125 I was injected intravenously and mesenteric lymph was collected. results suggesting that DBP may be transferred from blood to mesenteric lymph and that plasma and lymph DBP may have a similar origin

Efficiency and fidelity of cell-free protein synthesis by transfer RNA from aged mice

Energy Technology Data Exchange (ETDEWEB)

Foote, R.S.; Stulberg, M.P.

1980-01-01

Transfer RNAs (tRNAs) from heart, kidney, liver, and spleen of mature (10 to 12 months old) and aged (29 months old) C57BL/6 mice were tested for their ability to translate encephalomyocarditis viral RNA in a tRNA-dependent cell-free system derived from mouse ascites tumor cells. The rates of in vitro protein synthesis were compared as a function of tRNA concentration, and the fidelity of translation was examined by sodium dodecyl sulfate gel electrophoresis and isoelectric focusing of the viral polypeptides synthesized in vitro. No significant age-related differences in either the efficiency or fidelity of synthesis were discovered, indicating that alternations in tRNAs are probably not involved in the cellular aging of these tissues.

Blotting from PhastGel to Membranes by Ultrasound.

Science.gov (United States)

Kost, Joseph; Azagury, Aharon

2015-01-01

Ultrasound based approach for enhanced protein blotting is proposed. Three minutes of ultrasound exposure (1 MHz, 2.5 W/cm(2)) was sufficient for a clear transfer of proteins from a polyacrylamide gel (PhastGel) to nitrocellulose or Nylon 66 Biotrans membrane. The proteins evaluated were prestained sodium dodecyl sulfate-polyacrylamide standards (18,500-106,000 Da) and 14C-labeled Rainbow protein molecular weight markers (14,300-200,000 Da).

Cocrystal solubility-pH and drug solubilization capacity of sodium dodecyl sulfate – mass action model for data analysis and simulation to improve design of experiments

Directory of Open Access Journals (Sweden)

Alex Avdeef

2018-06-01

Full Text Available This review discusses the disposition of the anionic surfactant, sodium dodecyl sulfate (SDS; i.e., sodium lauryl sulfate, to solubilize sparingly-soluble drugs above the surfactant critical micelle concentration (CMC, as quantitated by the solubilization capacity (k. A compilation of 101 published SDS k values of mostly poorly-soluble drug molecules was used to develop a prediction model as a function of the drug’s intrinsic solubility, S0, and its calculated H-bond acceptor/donor potential. In almost all cases, the surfactant was found to solubilize the neutral form of the drug. Using the mass action model, the k values were converted to drug-micelle stoichiometric binding constants, Kn, corresponding to drug-micelle equilibria in drug-saturated solutions. An in-depth case study (data from published sources considered the micellization reactions as a function of pH of a weak base, B, (pKa 3.58, S0 52 μg/mL, where at pH 1 the BH.SDS salt was predicted to precipitate both below and above the CMC. At low SDS concentrations, two drug salts were predicted to co-precipitate: BH.Cl and BH.SDS. Solubility products of both were determined from the analysis of the reported solubility-surfactant data. Above the CMC, in a rare example, the charged form of the drug (BH+ appeared to be strongly solubilized by the surfactant. The constant for that reaction was also determined. At pH 7, the reactions were simpler, as only the neutral form of the drug was solubilized, to a significantly lesser extent than at pH 1. Case studies also featured examples of solubilization of solids in the form of cocrystals. For many cocrystal systems studied in aqueous solution, the anticipated supersaturated state is not long-lasting, as the drug component precipitates to a thermodynamically stable form, thus lowering the amount of the active ingredient available for intestinal absorption. Use of surfactant can prevent this. A recently-described method for predicting the

Isolation of eukaryotic ribosomal proteins. Purification and characterization of the 60 S ribosomal subunit proteins L4, L5, L7, L9, L11, L12, L13, L21, L22, L23, L26, L27, L30, L33, L35', L37, and L39.

Science.gov (United States)

Tsurugi, K; Collatz, E; Wool, E G; Lin, A

1976-12-25

The proteins of the large subunit of rat liver ribosomes were separated into seven groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Seventeen proteins (L4, L5, L7, L9, L11, L12, L13, L21, L22, L23, L26, L27, L30, L33, L35', L37, and L39) were isolated from three of the groups (B60, D60, G60) by ion exchange chromatography on carboxymethylcellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.5 to 15 mg. Eight of the proteins (L9, L11, L13, L21, L22, L35', L37 and L39) had no detectable contamination; the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.

Expression and purification of recombinant polyomavirus VP2 protein and its interactions with polyomavirus proteins

Science.gov (United States)

Cai, X.; Chang, D.; Rottinghaus, S.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

1994-01-01

Recombinant polyomavirus VP2 protein was expressed in Escherichia coli (RK1448), using the recombinant expression system pFPYV2. Recombinant VP2 was purified to near homogeneity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroelution, and Extracti-Gel chromatography. Polyclonal serum to this protein which reacted specifically with recombinant VP2 as well as polyomavirus virion VP2 and VP3 on Western blots (immunoblots) was produced. Purified VP2 was used to establish an in vitro protein-protein interaction assay with polyomavirus structural proteins and purified recombinant VP1. Recombinant VP2 interacted with recombinant VP1, virion VP1, and the four virion histones. Recombinant VP1 coimmunoprecipitated with recombinant VP2 or truncated VP2 (delta C12VP2), which lacked the carboxy-terminal 12 amino acids. These experiments confirmed the interaction between VP1 and VP2 and revealed that the carboxyterminal 12 amino acids of VP2 and VP3 were not necessary for formation of this interaction. In vivo VP1-VP2 interaction study accomplished by cotransfection of COS-7 cells with VP2 and truncated VP1 (delta N11VP1) lacking the nuclear localization signal demonstrated that VP2 was capable of translocating delta N11VP1 into the nucleus. These studies suggest that complexes of VP1 and VP2 may be formed in the cytoplasm and cotransported to the nucleus for virion assembly to occur.

Interrogation of an autofluorescence-based method for protein fingerprinting.

Science.gov (United States)

Siddaramaiah, Manjunath; Rao, Bola Sadashiva S; Joshi, Manjunath B; Datta, Anirbit; Sandya, S; Vishnumurthy, Vasudha; Chandra, Subhash; Nayak, Subramanya G; Satyamoorthy, Kapaettu; Mahato, Krishna K

2018-03-14

In the present study, we have designed a laser-induced fluorescence (LIF) based instrumentation and developed a sensitive methodology for the effective separation, visualization, identification and analysis of proteins on a single platform. In this method, intrinsic fluorescence spectra of proteins were detected after separation on 1 or 2 dimensional Sodium Dodecyl Sulfate-Tris(2-carboxyethyl)phosphine (SDS-TCEP) polyacrylamide gel electrophoresis (PAGE) and the data were analyzed. The MATLAB assisted software was designed for the development of PAGE fingerprint for the visualization of protein after 1- and 2-dimensional protein separation. These provided objective parameters of intrinsic fluorescence intensity, emission peak, molecular weight and isoelectric point using a single platform. Further, the current architecture could differentiate the overlapping proteins in the PAGE gels which otherwise were not identifiable by conventional staining, imaging and tagging methods. Categorization of the proteins based on the presence or absence of tyrosine or tryptophan residues and assigning the corresponding emission peaks (309-356 nm) with pseudo colors allowed the detection of proportion of proteins within the given spectrum. The present methodology doesn't use stains or tags, hence amenable to couple with mass spectroscopic measurements. This technique may have relevance in the field of proteomics that is used for innumerable applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A natural coagulant protein from Moringa oleifera: isolation, characterization, and potential use for water treatment

Science.gov (United States)

Choudhary, Manisha; Neogi, Sudarsan

2017-10-01

In developing countries pond water is still widely used for drinking and household purposes, which develops higher turbidity during rainy seasons and requires a large amount of chemical coagulants, and this leads to high cost of treatment. To mitigate this, it is important to find an economical and natural coagulant to treat turbid water. The present study is focused on using a plant based component as a natural coagulant that is sustainable and environment-friendly. This work focuses on the extraction, isolation and purification of a natural coagulant from seed kernels of Moringa oleifera to enhance its turbidity removal efficiency. The determination of themolecular weight of the purified proteins was done using sodium dodecyl sulfate polyacrylamide gel electrophoresis. The active coagulant proteins were isolated using 30-60% and 60-80% saturation of ammonium sulfate. It was observed that proteins with molecular weight less than 36 kDa have superior coagulation activity. Turbidity removal efficiency of these active coagulant proteins was compared with alum. The possibility of using Moringa oleifera seeds as a natural antimicrobial agent was also investigated.

Impact of casein and egg white proteins on the structure of wheat gluten-based protein-rich food.

Science.gov (United States)

Wouters, Arno G B; Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

2016-02-01

There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods. © 2015 Society of Chemical Industry.

Effects of foaming and antifoaming agents on the performance of a wet flue gas desulfurization pilot plant

DEFF Research Database (Denmark)

Qin, Siqiang; Hansen, Brian Brun; Kiil, Søren

2014-01-01

Foaming is a common phenomenon in industrial processes, including wet flue gas desulfurization (FGD) plants. A systemic investigation of the influence of two foaming agents, sodium dodecyl sulphate (SDS) and egg white albumin (protein), and two commercial antifoams on a wet FGD pilot plant...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) as well as native polyacrylamide gel electrophoresis (native-PAGE) produced single protein bands indicating that the enzyme preparation was pure. Molecular mass of the enzyme determined from SDS-PAGE analysis was 64 kDa. Using 2 ...

Development and Characterization of Sodium Hyaluronate Microparticle-Based Sustained Release Formulation of Recombinant Human Growth Hormone Prepared by Spray-Drying.

Science.gov (United States)

Kim, Sun J; Kim, Chan W

2016-02-01

The purpose of this study was to develop and characterize a sodium hyaluronate microparticle-based sustained release formulation of recombinant human growth hormone (SR-rhGH) prepared by spray-drying. Compared to freeze-drying, spray-dried SR-rhGH showed not only prolonged release profiles but also better particle property and injectability. The results of size-exclusion high-performance liquid chromatography showed that no aggregate was detected, and dimer was just about 2% and also did not increase with increase of inlet temperature up to 150 °C. Meanwhile, the results of reversed-phase high-performance liquid chromatography revealed that related proteins increased slightly from 4.6% at 100 °C to 6.3% at 150 °C. Thermal mapping test proved that product temperature did not become high to cause protein degradation during spray-drying because thermal energy was used for the evaporation of surface moisture of droplets. The structural characterization by peptide mapping, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and circular dichroism revealed that the primary, secondary, and tertiary structures of rhGH in SR-rhGH were highly comparable to those of reference somatropin materials. The biological characterization by rat weight gain and cell proliferation assays provided that bioactivity of SR-rhGH was equivalent to that of native hGH. These data establish that spray-dried SR-rhGH is highly stable by preserving intact rhGH and hyaluronate microparticle-based formulation by spray-drying can be an alternative delivery system for proteins. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Identification of high-affinity calmodulin-binding proteins in rat liver

International Nuclear Information System (INIS)

Hanley, R.M.; Dedman, J.R.; Shenolikar, S.

1987-01-01

The Ca 2+ -dependent binding of [ 125 I] calmodulin (CaM) to hepatic proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was utilized to identify CaM binding or acceptor proteins or CAPs. Two proteins of apparent molecular weight of 60,000 (CAP-60) and 45,000 (CAP-45) comprised > 80% of the Ca 2+ -dependent CaM binding in rat liver cytosol. CAP-60 and CAP-45 were partially purified by a variety of chromatographic steps, including affinity chromatography on CaM Sepharose. CAP-60 possessed a native molecular size of 400,000, indicating it to be the CaM-binding subunit of a larger oligomeric complex. In contrast, CAP-45 was monomeric as judged by gel filtration. Neither CAP-60 nor CAP-45 possessed chromatographic properties consistent with known CaM-dependent enzymes reported in the literature. Two-dimensional peptide mapping provided convincing evidence that CAP-60 and CAP-45 were unrelated to other well-characterized CAPs, namely Ca 2+ (CaM)-dependent protein kinase II, calcineurin, or the CaM-dependent cyclic nucleotide phosphodiesterase. The relative abundance and high affinity for CaM could suggest that these novel target proteins, CAP-60 and CAP-45, represent a dominant pathway for CaM action in the mammalian liver

The effect of a high-protein, high-sodium diet on calcium and bone metabolism in postmenopausal women stratified by hormone replacement therapy use

DEFF Research Database (Denmark)

Harrington, M.; Bennett, T.; Jakobsen, Jette

2004-01-01

The objective of this study was to investigate the influence of a high-sodium, high-protein diet on bone metabolism in postmenopausal women ( aged 49 - 60 y) stratified by hormone replacement therapy (HRT) use. In a crossover trial, 18 women (n = 8 HRT users (+HRT) and n = 10 nonusers (-HRT)) were...... randomly assigned to a diet high in protein ( 90 g/day) and sodium (180 mmol/day) ( calciuric diet) or a diet moderate in protein ( 70 g/day) and low in sodium ( 65 mmol/day) for 4 weeks followed by crossover to alternative dietary regimen for a further 4 weeks. The calciuric diet significantly (P...

Molecular biology of Neisseria meningitidis class 5 and H. 8 outer membrane proteins

Energy Technology Data Exchange (ETDEWEB)

Kawula, T.H.

1987-01-01

One of the surface structures responsible for inter- and intrastrain antigenic variability in meningococci is the heat-modifiable class 5 (C.5) protein. Neisseria meningitidis strain FAM18 (a meningococcal disease isolate) expressed two different C.5 proteins (C.5a and C.5b) identifiable by sodium dodecyl sulfate polyacrylamide gel electrophoresis. We generated two monoclonal antibodies (MAbs), each specific for one of the identified C.5 proteins. The MAbs, which were bactericidal for variants expressing the appropriate C.5 protein, were used to study C.5 expression changes in FAM18. The H.8 protein is an antigenically conserved outer membrane protein expressed almost exclusively by the pathogenic Neisseria. We have cloned and sequenced an H.8 gene from N. meningitidis FAM18. The predicted H.8 amino acid sequence indicated that the most probable signal peptide processing site matched the consensus prokaryotic lipoprotein processing/modification sequence. We then showed that the H.8 protein could be labeled with {sup 14}C-palmitic acid, confirming that H.8 was a lipoprotein. Processing of the H.8 protein was inhibited by globomycin in E. coli indicating that H.8 was modified by the described lipoprotein processing/modifying pathway described in both gram negative and gram positive genera.

Overexpression of avenin-like b proteins in bread wheat (Triticum aestivum L.) improves dough mixing properties by their incorporation into glutenin polymers.

Science.gov (United States)

Ma, Fengyun; Li, Miao; Li, Tingting; Liu, Wei; Liu, Yunyi; Li, Yin; Hu, Wei; Zheng, Qian; Wang, Yaqiong; Li, Kexiu; Chang, Junli; Chen, Mingjie; Yang, Guangxiao; Wang, Yuesheng; He, Guangyuan

2013-01-01

Avenin-like b proteins are a small family of wheat storage proteins, each containing 18 or 19 cysteine residues. The role of these proteins, with high numbers of cysteine residues, in determining the functional properties of wheat flour is unclear. In the present study, two transgenic lines of the bread wheat overexpressing avenin-like b gene were generated to investigate the effects of Avenin-like b proteins on dough mixing properties. Sodium dodecyl sulfate sedimentation (SDSS) test and Mixograph analysis of these lines demonstrated that overexpression of Avenin-like b proteins in both transgenic wheat lines significantly increased SDSS volume and improved dough elasticity, mixing tolerance and resistance to extension. These changes were associated with the increased proportion of polymeric proteins due to the incorporation of overexpressed Avenin-like b proteins into the glutenin polymers. The results of this study were critical to confirm the hypothesis that Avenin-like b proteins could be integrated into glutenin polymers by inter-chain disulphide bonds, which could help understand the mechanism behind strengthening wheat dough strength.

Overexpression of avenin-like b proteins in bread wheat (Triticum aestivum L. improves dough mixing properties by their incorporation into glutenin polymers.

Directory of Open Access Journals (Sweden)

Fengyun Ma

Full Text Available Avenin-like b proteins are a small family of wheat storage proteins, each containing 18 or 19 cysteine residues. The role of these proteins, with high numbers of cysteine residues, in determining the functional properties of wheat flour is unclear. In the present study, two transgenic lines of the bread wheat overexpressing avenin-like b gene were generated to investigate the effects of Avenin-like b proteins on dough mixing properties. Sodium dodecyl sulfate sedimentation (SDSS test and Mixograph analysis of these lines demonstrated that overexpression of Avenin-like b proteins in both transgenic wheat lines significantly increased SDSS volume and improved dough elasticity, mixing tolerance and resistance to extension. These changes were associated with the increased proportion of polymeric proteins due to the incorporation of overexpressed Avenin-like b proteins into the glutenin polymers. The results of this study were critical to confirm the hypothesis that Avenin-like b proteins could be integrated into glutenin polymers by inter-chain disulphide bonds, which could help understand the mechanism behind strengthening wheat dough strength.

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

Science.gov (United States)

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

1978-09-01

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

Carrier ampholyte-free isoelectric focusing on a paper-based analytical device for the fractionation of proteins.

Science.gov (United States)

Xie, Song-Fang; Gao, Han; Niu, Li-Li; Xie, Zhen-Sheng; Fang, Fang; Wu, Zhi-Yong; Yang, Fu-Quan

2018-01-25

Isoelectric focusing plays a critical role in the analysis of complex protein samples. Conventionally, isoelectric focusing is implemented with carrier ampholytes in capillary or immobilized pH gradient gel. In this study, we successfully exhibited a carrier ampholyte-free isoelectric focusing on paper-based analytical device. Proof of the concept was visually demonstrated with color model proteins. Experimental results showed that not only a pH gradient was well established along the open paper fluidic channel as confirmed by pH indicator strip, the pH gradient range could also be tuned by the catholyte or anolyte. Furthermore, the isoelectric focusing fractions from the paper channel can be directly cut and recovered into solutions for post analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. This paper-based isoelectric focusing method is fast, cheap, simple and easy to operate, and could potentially be used as a cost-effective protein sample clean-up method for target protein analysis with mass spectrometry. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Covalent modification of platelet proteins by palmitate

International Nuclear Information System (INIS)

Muszbek, L.; Laposata, M.

1989-01-01

Covalent attachment of fatty acid to proteins plays an important role in association of certain proteins with hydrophobic membrane structures. In platelets, the structure of many membrane glycoproteins (GPs) has been examined in detail, but the question of fatty acid acylation of platelet proteins has not been addressed. In this study, we wished to determine (a) whether platelet proteins could be fatty acid acylated; and, if so, (b) whether these modified proteins were present in isolated platelet membranes and cytoskeletal fractions; and (c) if the pattern of fatty acid acylated proteins changed on stimulation of the platelets with the agonist thrombin. We observed that in platelets allowed to incorporate 3H-palmitate, a small percentage (1.37%) of radioactivity incorporated into the cells became covalently bound to protein. Selective cleavage of thioester, thioester plus O-ester, and amide-linked 3H-fatty acids from proteins, and their subsequent analysis by high-performance liquid chromatography (HPLC) indicated that the greatest part of 3H-fatty acid covalently bound to protein was thioester-linked 3H-palmitate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorography, at least ten major radiolabeled proteins were detected. Activation of platelets by thrombin greatly increased the quantity of 3H-palmitoylated proteins associated with the cytoskeleton. Nearly all radiolabeled proteins were recovered in the membrane fraction, indicating that these proteins are either integral or peripheral membrane proteins or proteins tightly associated to membrane constituents. Components of the GPIIb-IIIa complex were not palmitoylated. Thus, platelet proteins are significantly modified posttranslationally by 3H-palmitate, and incorporation of palmitoylated proteins into the cytoskeleton is a prominent component of the platelet response to thrombin stimulation

Interactions between a poorly soluble cationic drug and sodium dodecyl sulfate in dissolution medium and their impact on in vitro dissolution behavior.

Science.gov (United States)

Huang, Zongyun; Parikh, Shuchi; Fish, William P

2018-01-15

In the pharmaceutical industry, in vitro dissolution testing ofsolid oral dosage forms is a very important tool for drug development and quality control. However, ion-pairing interaction between the ionic drugand surfactants in dissolution medium often occurs, resulting in inconsistent and incomplete drug release. The aim of this study is toevaluate the effects ofsodium dodecyl sulfate (SDS) mediated medium onthe dissolution behaviors of a poorly soluble cationic drug (Drug B). The study was carried out by measuring solubility of Drug B substance and dissolution rate of Drug B product in media containing SDS.Desolubilization of Drug B substance was observed at pH 4.5 in the presence of SDS at concentrations below critical micelle concentration (CMC) which is attributed to the formation of an insoluble di-dodecyl sulfate salt between SDS and Drug B. This ion-pairing effect is less significant with increasing medium pH where Drug B is less ionized and CMC of SDS is lower. In medium at pH 4.5, dissolution of Drug B product was found incomplete with SDS concentration below CMC due to the desolubilization of Drug B substance. In media with SDS level above CMC, the dissolution rate is rather slower with higher inter-vessel variations compared to that obtained in pH 4.5 medium without SDS. The dissolution results demonstrate that the presence of SDS in medium generates unexpected irregular dissolution profiles for Drug B which are attributed to incompatible dissolution medium for this particular drug. Therefore, non-ionic surfactant was selected for Drug B product dissolution method and ion-pairing effect in SDS mediated medium should be evaluated when developing a dissolution method for any poorly soluble cationic drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

A family of related proteins is encoded by the major Drosophila heat shock gene family

International Nuclear Information System (INIS)

Wadsworth, S.C.

1982-01-01

At least four proteins of 70,000 to 75,000 molecular weight (70-75K) were synthesized from mRNA which hybridized with a cloned heat shock gene previously shown to be localized to the 87A and 87C heat shock puff sites. These in vitro-synthesized proteins were indistinguishable from in vivo-synthesized heat shock-induced proteins when analyzed on sodium dodecyl sulfate-polyacrylamide gels. A comparison of the pattern of this group of proteins synthesized in vivo during a 5-min pulse or during continuous labeling indicates that the 72-75K proteins are probably not kinetic precursors to the major 70K heat shock protein. Partial digestion products generated with V8 protease indicated that the 70-75K heat shock proteins are closely related, but that there are clear differences between them. The partial digestion patterns obtained from heat shock proteins from the Kc cell line and from the Oregon R strain of Drosophila melanogaster are very similar. Genetic analysis of the patterns of 70-75K heat shock protein synthesis indicated that the genes encoding at least two of the three 72-75K heat shock proteins are located outside of the major 87A and 87C puff sites

Identification and primary characterization of a plant antimicrobial ...

African Journals Online (AJOL)

Then an agar-overlay method using fully separated proteins on sodium dodecyl sulphate-polyacryliamide gel electrophoresis (SDS-PAGE) gels was used for initial determination and primary characterization of active putative defensins in the plant seeds. Clear and remarkable zones of inhibition in a region corresponding to ...

Genetic transformation of Physcomitrella patens mediated by ...

African Journals Online (AJOL)

USER

2010-06-21

Jun 21, 2010 ... plants could be obtained after 4 generations of selective culture. PCR analysis showed that gene ... 5'-triphosphate; SDS, sodium dodecyl sulfate; YFP, your favorite protein. ..... affected the transformation rate mediated by Agro- bacterium, this was confirmed and the result showed only the gametophores ...

Studies on voltammetric determination of cadmium in samples containing native and digested proteins

Energy Technology Data Exchange (ETDEWEB)

Drozd, Marcin; Pietrzak, Mariusz, E-mail: mariusz@ch.pw.edu.pl; Malinowska, Elżbieta

2014-03-01

Highlights: • Proteins exhibit diverse impact on the DPASV cadmium signals. • Proteins subjected to HNO{sub 3} introduce less interference, than the native ones. • Optimal amount of SDS depends on the kind of protein. • Presence of thiolated coating agents of QDs do not influence the analysis. - Abstract: This work focuses on determination of cadmium ions using anodic stripping voltammetry (ASV) on thin film mercury electrode in conditions corresponding to those obtained after digestion of cadmium-based quantum dots and their conjugates. It presents the impact of selected proteins, including potential receptors and surface blocking agents on the voltammetric determination of cadmium. Experiments regarding elimination of interferences related to proteins presence using sodium dodecyl sulfate (SDS) are also shown. Effect of SDS on selected analytical parameters and simplicity of analyses carried out was investigated in the framework of current studies. The significant differences of influence among tested proteins on ASV cadmium determination, as well as the variability in SDS effectiveness as the antifouling agent were observed and explained. This work is especially important for those, who design new bioassays and biosensors with a use of quantum dots as electrochemical labels, as it shows what problems may arise from presence of native and digested proteins in tested samples.

Analysis of polymorphisms in milk proteins from cloned and sexually reproduced goats.

Science.gov (United States)

Xing, H; Shao, B; Gu, Y Y; Yuan, Y G; Zhang, T; Zang, J; Cheng, Y

2015-12-08

This study evaluates the relationship between the genotype and milk protein components in goats. Milk samples were collected from cloned goats and normal white goats during different postpartum (or abortion) phases. Two cloned goats, originated from the same somatic line of goat mammary gland epithelial cells, and three sexually reproduced normal white goats with no genetic relationships were used as the control. The goats were phylogenetically analyzed by polymerase chain reaction-restriction fragment length polymorphism. The milk protein components were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The results indicated that despite the genetic fingerprints being identical, the milk protein composition differed between the two cloned goats. The casein content of cloned goat C-50 was significantly higher than that of cloned goat C-4. Conversely, although the genetic fingerprints of the normal white goats N-1, N-2, and N-3 were not identical, the milk protein profiles did not differ significantly in their milk samples (obtained on postpartum day 15, 20, 25, 30, and 150). These results indicated an association between milk protein phenotypes and genetic polymorphisms, epigenetic regulation, and/or non-chromosomal factors. This study extends the knowledge of goat milk protein polymorphisms, and provides new strategies for the breeding of high milk-yielding goats.

Kinetic Stability of Proteins in Beans and Peas: Implications for Protein Digestibility, Seed Germination, and Plant Adaptation.

Science.gov (United States)

Xia, Ke; Pittelli, Sandy; Church, Jennifer; Colón, Wilfredo

2016-10-12

Kinetically stable proteins (KSPs) are resistant to the denaturing detergent sodium dodecyl sulfate (SDS). Such resilience makes KSPs resistant to proteolytic degradation and may have arisen in nature as a mechanism for organismal adaptation and survival against harsh conditions. Legumes are well-known for possessing degradation-resistant proteins that often diminish their nutritional value. Here we applied diagonal two-dimensional (D2D) SDS-polyacrylamide gel electrophoresis (PAGE), a method that allows for the proteomics-level identification of KSPs, to a group of 12 legumes (mostly beans and peas) of agricultural and nutritional importance. Our proteomics results show beans that are more difficult to digest, such as soybean, lima beans, and various common beans, have high contents of KSPs. In contrast, mung bean, red lentil, and various peas that are highly digestible contain low amounts of KSPs. Identified proteins with high kinetic stability are associated with warm-season beans, which germinate at higher temperatures. In contrast, peas and red lentil, which are cool-season legumes, contain low levels of KSPs. Thus, our results show protein kinetic stability is an important factor in the digestibility of legume proteins and may relate to nutrition efficiency, timing of seed germination, and legume resistance to biotic stressors. Furthermore, we show D2D SDS-PAGE is a powerful method that could be applied for determining the abundance and identity of KSPs in engineered and wild legumes and for advancing basic research and associated applications.

Sample Stability and Protein Composition of Saliva: Implications for Its Use as a Diagnostic Fluid

Directory of Open Access Journals (Sweden)

Han Roelofsen

2008-01-01

Full Text Available Saliva is an easy accessible plasma ultra-filtrate. Therefore, saliva can be an attractive alternative to blood for measurement of diagnostic protein markers. Our aim was to determine stability and protein composition of saliva. Protein stability at room temperature was examined by incubating fresh whole saliva with and without inhibitors of proteases and bacterial metabolism followed by Surface Enhanced Laser Desorption/Ionization (SELDI analyses. Protein composition was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE fractionation of saliva proteins followed by digestion of excised bands and identification by liquid chromatography tandem mass spectrometry (LC-MS/MS. Results show that rapid protein degradation occurs within 30 minutes after sample collection. Degradation starts already during collection. Protease inhibitors partly prevented degradation while inhibition of bacterial metabolism did not affect degradation. Three stable degradation products of 2937 Da, 3370 Da and 4132 Da were discovered which can be used as markers to monitor sample quality. Saliva proteome analyses revealed 218 proteins of which 84 can also be found in blood plasma. Based on a comparison with seven other proteomics studies on whole saliva we identified 83 new saliva proteins. We conclude that saliva is a promising diagnostic fl uid when precautions are taken towards protein breakdown.

A Patient with MSUD: Acute Management with Sodium Phenylacetate/Sodium Benzoate and Sodium Phenylbutyrate

OpenAIRE

K?se, Melis; Canda, Ebru; Kagnici, Mehtap; U?ar, Sema Kalkan; ?oker, Mahmut

2017-01-01

In treatment of metabolic imbalances caused by maple syrup urine disease (MSUD), peritoneal dialysis, and hemofiltration, pharmacological treatments for elimination of toxic metabolites can be used in addition to basic dietary modifications. Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate (NaPB) in urea-cycle disorder cases has been associated with a reduction in branched-chain amino acid (BCAA) concentrations when the patients are on adequate dietary protein intake. Moreo...

Langmuir film of regioregular poly(4-dodecyl-2,2'-bithiophene)

NARCIS (Netherlands)

Greve, D.R.; Dynarowicz-Latka, P.; Dhanabalan, A.; Janssen, R.A.J.

2002-01-01

Regioregular poly(4-dodecyl-2,2'-bithiophene) (P4DBT) is synthesized via the McCullough polymerization route using Ni(dppp)Cl2 as a catalyst and characterized by UV–visible and nuclear magnetic resonance spectroscopy. The film-forming properties of P4DBT at the air–water interface are investigated

Glutenin composition, quality characteristics, and agronomic ...

African Journals Online (AJOL)

ABSTRACT Eleven cultivars of durum wheat (Triticum durum L. var. durum Desf.) ... Gluten strength was measured by the sodium dodecyl sulfate (SDS) sedimentation test. ... Significant genotypic differences were observed for grain yield, 1000 kernel weight, protein content, ... (Af Crop Sci J 2002 Vol 10 No 2 pp173-182).

Pouring and running a protein gel by reusing commercial cassettes.

Science.gov (United States)

Hwang, Alexander C; Grey, Paris H; Cuddy, Katrina; Oppenheimer, David G

2012-02-12

The evaluation of proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis is a common technique used by biochemistry and molecular biology researchers. For laboratories that perform daily analyses of proteins, the cost of commercially available polyacrylamide gels (~$10/gel) can be considerable over time. To mitigate this cost, some researchers prepare their own polyacrylamide gels. Traditional methods of pouring these gels typically utilize specialized equipment and glass gel plates that can be expensive and preclude pouring many gels and storing them for future use. Furthermore, handling of glass plates during cleaning or gel pouring can result in accidental breakage creating a safety hazard, which may preclude their use in undergraduate laboratory classes. Our protocol demonstrates how to pour multiple protein gels simultaneously by recycling Invitrogen Nupage Novex minigel cassettes, and inexpensive materials purchased at a home improvement store. This economical and streamlined method includes a way to store the gels at 4°C for a few weeks. By re-using the plastic gel cassettes from commercially available gels, labs that run frequent protein gels can save significant costs and help the environment. In addition, plastic gel cassettes are extremely resistant to breakage, which makes them ideal for undergraduate laboratory classrooms.

Sodium appetite elicited by low-sodium diet is dependent on p44/42 mitogen-activated protein kinase (extracellular signal-regulated kinase 1/2) activation in the brain.

Science.gov (United States)

Monteiro, L R N; Marangon, P B; Elias, L L K; Reis, L C; Antunes-Rodrigues, J; Mecawi, A S

2017-09-01

Sodium appetite is regulated by several signalling molecules, among which angiotensin II (Ang II) serves as a key driver of robust salt intake by binding to Ang II type 1 receptors (AT1R) in several regions in the brain. The activation of these receptors recruits the mitogen-activated protein kinase (MAPK) pathway, which has previously been linked to Ang II-induced increases in sodium appetite. Thus, we addressed the involvement of MAPK signalling in the induction of sodium appetite after 4 days of low-sodium diet consumption. An increase in extracellular signal-regulated kinase (ERK) phosphorylation in the laminae terminalis and mediobasal hypothalamus was observed after low-sodium diet consumption. This response was reduced by i.c.v. microinjection of an AT1R antagonist into the laminae terminalis but not the hypothalamus. This result indicates that low-sodium diet consumption activates the MAPK pathway via Ang II/AT1R signalling on the laminae terminalis. On the other hand, activation of the MAPK pathway in the mediobasal hypothalamus after low-sodium diet consumption appears to involve another extracellular mediator. We also evaluated whether a low-sodium diet could increase the sensitivity for Ang II in the brain and activate the MAPK pathway. However, i.c.v. injection of Ang II increased ERK phosphorylation on the laminae terminalis and mediobasal hypothalamus; this increase achieved a response magnitude similar to those observed in both the normal and low-sodium diet groups. These data indicate that low-sodium diet consumption for 4 days is insufficient to change the ERK phosphorylation response to Ang II in the brain. To investigate whether the MAPK pathway is involved in sodium appetite after low-sodium diet consumption, we performed i.c.v. microinjections of a MAPK pathway inhibitor (PD98059). PD98059 inhibited both saline and water intake after low-sodium diet consumption. Thus, the MAPK pathway is involved in promoting the sodium appetite after low-sodium

Sodium modulates opioid receptors through a membrane component different from G-proteins. Demonstration by target size analysis

International Nuclear Information System (INIS)

Ott, S.; Costa, T.; Herz, A.

1988-01-01

The target size for opioid receptor binding was studied after manipulations known to affect the interactions between receptor and GTP-binding regulatory proteins (G-proteins). Addition of GTP or its analogs to the binding reaction, exposure of intact cells to pertussis toxin prior to irradiation, or treatment of irradiated membranes with N-ethylmaleimide did not change the target size (approximately equal to 100 kDa) for opioid receptors in NG 108-15 cells and rat brain. These data suggest that the 100-kDa species does not include an active subunit of a G-protein or alternatively that GTP does not promote the dissociation of the receptor-G-protein complex. The presence of Na+ (100 mM) in the radioligand binding assay induced a biphasic decay curve for agonist binding and a flattening of the monoexponential decay curve for a partial agonist. In both cases the effect was explained by an irradiation-induced loss of the low affinity state of the opioid receptor produced by the addition of Na+. This suggests that an allosteric inhibitor that mediates the effect of sodium on the receptor is destroyed at low doses of irradiation, leaving receptors which are no longer regulated by sodium. The effect of Na+ on target size was slightly increased by the simultaneous addition of GTP but was not altered by pertussis toxin treatment. Thus, the sodium unit is distinct from G-proteins and may represent a new component of the opioid receptor complex. Assuming a simple bimolecular model of one Na+ unit/receptor, the size of this inhibitor can be measured as 168 kDa

Sodium 4-Phenylbutyrate Attenuates Myocardial Reperfusion Injury by Reducing the Unfolded Protein Response.

Science.gov (United States)

Takatori, Osamu; Usui, Soichiro; Okajima, Masaki; Kaneko, Shuichi; Ootsuji, Hiroshi; Takashima, Shin-Ichiro; Kobayashi, Daisuke; Murai, Hisayoshi; Furusho, Hiroshi; Takamura, Masayuki

2017-05-01

The unfolded protein response (UPR) plays a pivotal role in ischemia-reperfusion (I/R) injury in various organs such as heart, brain, and liver. Sodium 4-phenylbutyrate (PBA) reportedly acts as a chemical chaperone that reduces UPR. In the present study, we evaluated the effect of PBA on reducing the UPR and protecting against myocardial I/R injury in mice. Male C57BL/6 mice were subjected to 30-minute myocardial I/R, and were treated with phosphate-buffered saline (as a vehicle) or PBA. At 4 hours after reperfusion, mice treated with PBA had reduced serum cardiac troponin I levels and numbers of apoptotic cells in left ventricles (LVs) in myocardial I/R. Infarct size had also reduced in mice treated with PBA at 48 hours after reperfusion. At 2 hours after reperfusion, UPR markers, including eukaryotic initiation of the factor 2α-subunit, activating transcription factor-6, inositol-requiring enzyme-1, glucose-regulated protein 78, CCAAT/enhancer-binding protein (C/EBP) homologous protein, and caspase-12, were significantly increased in mice treated with vehicle compared to sham-operated mice. Administration of PBA significantly reduced the I/R-induced increases of these markers. Cardiac function and dimensions were assessed at 21 days after I/R. Sodium 4-phenylbutyrate dedicated to the improvement of cardiac parameters deterioration including LV end-diastolic diameter and LV fractional shortening. Consistently, PBA reduced messenger RNA expression levels of cardiac remodeling markers such as collagen type 1α1, brain natriuretic peptide, and α skeletal muscle actin in LV at 21 days after I/R. Unfolded protein response mediates myocardial I/R injury. Administration of PBA reduces the UPR, apoptosis, infarct size, and preserved cardiac function. Hence, PBA may be a therapeutic option to attenuate myocardial I/R injury in clinical practice.

Identification of sporozoite surface proteins and antigens of Eimeria nieschulzi (Apicomplexa)

International Nuclear Information System (INIS)

Tilley, M.; Upton, S.J.

1990-01-01

Sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoblotting, lectin binding, and 125 I surface labeling of sporozoites were used to probe sporozoites of the rat coccidian, Eimeria nieschulzi. Analysis of silver stained gels revealed greater than 50 bands. Surface iodination revealed about 14 well labeled, and about 10 weakly labeled but potential, surface proteins. The most heavily labeled surface proteins had molecular masses of 60, 53-54, 45, 28, 23-24, 17, 15, 14, 13, and 12 kD. Following electrophoresis and Western blotting, 2 of the 12 125I labeled lectin probes bound to two bands on the blots, which collectively indicated that two bands were glycosylated. Concanavalin A (ConA) specifically recognized a band at 53 kD, which may represent a surface glycoprotein, and a lectin derived from Osage orange (MPA) bound to a single band at 82-88 kD, that may also be a surface molecule. Immunoblotting using sera collected from rats inoculated orally with oocysts, as well as sera from mice hyperimmunized with sporozoites, revealed that many surface molecules appear to be immunogenic

Differentiation of Shewanella putrefaciens and Shewanella alga on the basis of whole-cell protein profiles, ribotyping, phenotypic characterization, and 16S rRNA gene sequence analysis

DEFF Research Database (Denmark)

Vogel, Birte Fonnesbech; Jørgensen, K.; Christensen, H.

1997-01-01

Seventy-six presumed Shewanella putrefaciens isolates from fish, oil drillings, and clinical specimens, the type strain of Shewanella putrefaciens (ATCC 8071), the type strain of Shewanella alga (IAM 14159), and the type strain of Shewanella hanedai (ATCC 33224) were compared by several typing...... methods. Numerical analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell protein and ribotyping patterns showed that the strains were separated into two distinct clusters with 56% +/- 10% and 40% +/- 14% similarity for whole- cell protein profiling and ribotyping......, respectively. One cluster consisted of 26 isolates with 52 to 55 mol% G + C and included 15 human isolates, mostly clinical specimens, 8 isolates from marine waters, and the type strain of S. alga. This homogeneous cluster of mesophilic, halotolerant strains was by all analyses identical to the recently...

Aggregation of soy protein-isoflavone complexes and gel formation induced by glucono-δ-lactone in soymilk

Science.gov (United States)

Hsia, Sheng-Yang; Hsiao, Yu-Hsuan; Li, Wen-Tai; Hsieh, Jung-Feng

2016-10-01

This study investigated the glucono-δ-lactone (GDL)-induced aggregation of isoflavones and soy proteins in soymilk. High-performance liquid chromatography (HPLC) analysis indicated that isoflavones mixed with β-conglycinin (7S) and glycinin (11S) proteins formed 7S-isoflavone and 11S-isoflavone complexes in soymilk supernatant fraction (SSF). Most of the soy protein-isoflavone complexes then precipitated into the soymilk pellet fraction (SPF) following the addition of 4 mM GDL, whereupon the pH value of the soymilk dropped from 6.6 to 5.9. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and HPLC analysis suggest that the addition of 4 mM GDL induced the aggregation of most 7S (α’, α and β subunits), 11S acidic and 11S basic proteins as well as isoflavones, including most aglycones, including daidzein, glycitein, genistein and a portion of glucosides, including daidzin, glycitin, genistin, malonyldaidzin and malonylgenistin. These results provide an important reference pertaining to the effects of GDL on the aggregation of soy protein-isoflavone complexes and could benefit future research regarding the production of tofu from soymilk.

Production of Polyclonal Antibody against Grapevine fanleaf virus Movement Protein Expressed in Escherichia coli

Directory of Open Access Journals (Sweden)

Davoud Koolivand

2016-10-01

Full Text Available The genomic region of Grapevine fanleaf virus (GFLV encoding the movement protein (MP was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3 to express the protein. Induction was made with a wide range of isopropyl-β-D-thiogalactopyranoside (IPTG concentrations (1, 1.5, and 2 mM each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

Lol p XI, a new major grass pollen allergen, is a member of a family of soybean trypsin inhibitor-related proteins

NARCIS (Netherlands)

van Ree, R.; Hoffman, D. R.; van Dijk, W.; Brodard, V.; Mahieu, K.; Koeleman, C. A.; Grande, M.; van Leeuwen, W. A.; Aalberse, R. C.

1995-01-01

BACKGROUND: Monoclonal antibodies were obtained against an unknown allergen from Lolium perenne grass pollen. The allergen had an apparent molecular mass of 18 kd on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Earlier immunoblotting studies had shown that carbohydrate-specific IgG

Western Blotting using Capillary Electrophoresis

OpenAIRE

Anderson, Gwendolyn J.; Cipolla, Cynthia; Kennedy, Robert T.

2011-01-01

A microscale Western blotting system based on separating sodium-dodecyl sulfate protein complexes by capillary gel electrophoresis followed by deposition onto a blotting membrane for immunoassay is described. In the system, the separation capillary is grounded through a sheath capillary to a mobile X-Y translation stage which moves a blotting membrane past the capillary outlet for protein deposition. The blotting membrane is moistened with a methanol and buffer mixture to facilitate protein a...

How Chain Length and Charge Affect Surfactant Denaturation of Acyl Coenzyme A Binding Protein (ACBP)

DEFF Research Database (Denmark)

Andersen, Kell Kleiner; Otzen, Daniel

2009-01-01

maltoside (DDM). The aim has been to determine how surfactant chain length and micellar charge affect the denaturation mechanism. ACBP denatures in two steps irrespective of surfactant chain length, but with increasing chain length, the potency of the denaturant rises more rapidly than the critical micelle......Using intrinsic tryptophan fluorescence, equilibria and kinetics of unfolding of acyl coenzyme A binding protein (ACBP) have been investigated in sodium alkyl sulfate surfactants of different chain length (8-16 carbon atoms) and with different proportions of the nonionic surfactant dodecyl...... constants increases linearly with denaturant concentration below the cmc but declines at higher concentrations. Both shortening chain length and decreasing micellar charge reduce the overall kinetics of unfolding and makes the dependence of unfolding rate constants on surfactant concentration more complex...

Effects of CO₂ on Acer negundo pollen fertility, protein content, allergenic properties, and carbohydrates.

Science.gov (United States)

Silva, M; Ribeiro, H; Abreu, I; Cruz, A; Esteves da Silva, J C G

2015-05-01

Atmospheric gaseous pollutants can induce qualitative and quantitative changes in airborne pollen characteristics. In this work, it was investigated the effects of carbon dioxide (CO2) on Acer negundo pollen fertility, protein content, allergenic properties, and carbohydrates. Pollen was collected directly from the anthers and in vitro exposed to three CO2 levels (500, 1000, and 3000 ppm) for 6 and 24 h in an environmental chamber. Pollen fertility was determined using viability and germination assays, total soluble protein was determined with Coomassie Protein Assay Reagent, and the antigenic and allergenic properties were investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunological techniques using patients' sera. Also, pollen fructose, sucrose, and glucose values were determined. Carbon dioxide exposure affected negatively pollen fertility, total soluble protein content, and fructose content. The patient sera revealed increased IgE reactivity to proteins of A. negundo pollen exposed to increasing levels of the pollutant. No changes were detected in the SDS-PAGE protein profiles and in sucrose and glucose levels. Our results indicate that increase in atmospheric CO2 concentrations can have a negative influence of some features of A. negundo airborne pollen that can influence the reproductive processes as well as respiratory pollen allergies in the future.

Heat-stable proteins and abscisic acid action in barley aleurone cells

International Nuclear Information System (INIS)

Jacobsen, J.V.; Shaw, D.C.

1989-01-01

[ 35 S]Methionine labeling experiments showed that abscisic acid (ABA) induced the synthesis of at least 25 polypeptides in mature barley (Hordeum vulgare) aleurone cells. The polypeptides were not secreted. Whereas most of the proteins extracted from aleurone cells were coagulated by heating to 100 degree C for 10 minutes, most of the ABA-induced polypeptides remained in solution (heat-stable). ABA had little effect on the spectrum of polypeptides that were synthesized and secreted by aleurone cells, and most of these secreted polypeptides were also heat-stable. Coomassie blue staining of sodium dodecyl sulfate polyacrylamide gels indicated that ABA-induced polypeptides already occurred in high amounts in mature aleurone layers having accumulated during grain development. About 60% of the total protein extracted from mature aleurone was heat stable. Amino acid analyses of total preparations of heat-stable and heat-labile proteins showed that, compared to heat-labile proteins, heat-stable intracellular proteins were characterized by higher glutamic acid/glutamine (Glx) and glycine levels and lower levels of neutral amino acids. Secreted heat-stable proteins were rich in Glx and proline. The possibilities that the accumulation of the heat-stable polypeptides during grain development is controlled by ABA and that the function of these polypeptides is related to their abundance and extraordinary heat stability are considered

Study of adjuvant effect of model surfactants from the groups of alkyl sulfates, alkylbenzene sulfonates, alcohol ethoxylates and soaps

DEFF Research Database (Denmark)

Clausen, S K; Sobhani, S; Poulsen, O M

2000-01-01

The sodium salts of representatives of anionic surfactants, dodecylbenzene sulfonate (SDBS), dodecyl sulfate (SDS) and coconut oil fatty acids, and a nonionic surfactant, dodecyl alcohol ethoxylate, were studied for adjuvant effect on the production of specific IgE antibodies in mice. The surfact......The sodium salts of representatives of anionic surfactants, dodecylbenzene sulfonate (SDBS), dodecyl sulfate (SDS) and coconut oil fatty acids, and a nonionic surfactant, dodecyl alcohol ethoxylate, were studied for adjuvant effect on the production of specific IgE antibodies in mice...

Identification and analysis of a novel protein-tyrosine kinase from bovine thymus

International Nuclear Information System (INIS)

Zioncheck, T.F.; Harrison, M.L.; Geahlen, R.L.

1986-01-01

A cytosolic protein-tyrosine kinase has been identified and purified to near homogeneity from calf thymus by using the phosphorylation of the tyrosine-containing peptide angiotensin I as an assay. Specific peptide phosphorylating activity was enhanced by carrying out the assay at high ionic strength (2M NaCl). The inclusion of NaCl at this concentration acts to stimulate endogenous protein-tyrosine kinase activity while simultaneously inhibiting other endogenous kinases. The purification procedure involved extraction of the enzyme from calf-thymus and sequential chromatography on columns of DEAE-cellulose, heparin-agarose, casein-sepharose, butylagarose, and Sephadex G-75. Analysis of the most highly purified preparations by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single Coomassie blue-stained band of 41 KDa. This molecular weight was consistent with results obtained from gel filtration, indicating that the enzyme exists as a monomer. The enzyme has also been found to catalyze an autophosphorylation reaction. Incubation of the enzyme with Mn 2+ and [γ- 32 P]ATP led to its modification on a tyrosine residue. Phosphopeptide mapping experiments indicated that the 41 KDa kinase was distinct from p56, the major membrane-associated protein-tyrosine kinase in T lymphocytes

Determination of soy proteins in food samples by dispersive solid-phase immunoextraction and dynamic long-wavelength fluorometry

International Nuclear Information System (INIS)

Molina-Delgado, María Ángeles; Aguilar-Caballos, María Paz; Gomez-Hens, Agustina

2013-01-01

We report on a method for the determination of soy proteins in food samples via dispersive solid-phase immunoextraction using gold-coated magnetic nanoparticles (NPs) as a support. Soy proteins were first extracted using anti-soy protein antibodies immobilized on the NPs, and then quantified by measuring the increase in fluorescence of the long-wavelength fluorophore cresyl violet in the presence of the anionic surfactant sodium dodecyl sulfate at neutral pH in a flow system. The method involves the use of two standard or sample aliquots. The fluorescence intensity of one aliquot is directly measured whereas that of the other aliquot is measured after immunoextraction. The difference between the peak heights of both aliquots serves as the analytical information that is directly proportional to the protein concentration. The limit of detection is 0.35 mg L −1 , the linear range is from 1 to 15 mg L −1 , and the relative standard deviation is < 5 %. Proteins such as bovine serum albumin and globulins do not interfere at the same concentration level. The method was applied to the analysis of soy-based beverages and gave recoveries in the range between 80.0 and 107.3 %. (author)

Food-cooking processes modulate allergenic properties of hen's egg white proteins.

Science.gov (United States)

Liu, Xiaoyu; Feng, Bai-Sui; Kong, Xiaoli; Xu, Hong; Li, Xiumin; Yang, Ping-Chang; Liu, Zhigang

2013-01-01

Reducing the allergenicity of food allergens can suppress the clinical symptoms of food allergy. The objective of the present study was to investigate the effects of processing on the allergenic properties of hen's egg white proteins. Eggs were processed by traditional Chinese cooking, including steaming, water boiling, frying, spicing and tea boiling. The contents of processed egg protein were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis; the allergenicity was evaluated by Western blotting, enzyme-linked immunosorbent assay and enzyme allergosorbent test inhibition. Circular dichroism spectrum analysis of four major egg allergens from various egg products was performed as well. A mouse model of food allergy was developed to test the allergenicity of processed egg protein in vivo. Protein degradation was significant following tea boiling and spiced-tea boiling. The total allergenic potential of water-boiled egg and fried egg was relatively higher than that of steamed egg, spiced egg and tea-boiled egg. Challenge with proteins from raw egg, water-boiled egg and fried egg induced skewed T-helper 2 pattern responses (Th2 responses) in the intestine of mice sensitized to egg proteins; however, when the mice sensitized to egg proteins were challenged with proteins from steamed egg, spiced egg and tea-boiled egg, respectively, only weak Th2 responses were induced in their intestine. Processing by steaming, spicing, or tea boiling can weaken the allergenicity of egg proteins. Copyright © 2012 S. Karger AG, Basel.

Bromodomain-containing Protein 4 Activates Voltage-gated Sodium Channel 1.7 Transcription in Dorsal Root Ganglia Neurons to Mediate Thermal Hyperalgesia in Rats.

Science.gov (United States)

Hsieh, Ming-Chun; Ho, Yu-Cheng; Lai, Cheng-Yuan; Wang, Hsueh-Hsiao; Lee, An-Sheng; Cheng, Jen-Kun; Chau, Yat-Pang; Peng, Hsien-Yu

2017-11-01

Bromodomain-containing protein 4 binds acetylated promoter histones and promotes transcription; however, the role of bromodomain-containing protein 4 in inflammatory hyperalgesia remains unclear. Male Sprague-Dawley rats received hind paw injections of complete Freund's adjuvant to induce hyperalgesia. The dorsal root ganglia were examined to detect changes in bromodomain-containing protein 4 expression and the activation of genes involved in the expression of voltage-gated sodium channel 1.7, which is a key pain-related ion channel. The intraplantar complete Freund's adjuvant injections resulted in thermal hyperalgesia (4.0 ± 1.5 s; n = 7). The immunohistochemistry and immunoblotting results demonstrated an increase in the bromodomain-containing protein 4-expressing dorsal root ganglia neurons (3.78 ± 0.38 fold; n = 7) and bromodomain-containing protein 4 protein levels (2.62 ± 0.39 fold; n = 6). After the complete Freund's adjuvant injection, histone H3 protein acetylation was enhanced in the voltage-gated sodium channel 1.7 promoter, and cyclin-dependent kinase 9 and phosphorylation of RNA polymerase II were recruited to this area. Furthermore, the voltage-gated sodium channel 1.7-mediated currents were enhanced in neurons of the complete Freund's adjuvant rats (55 ± 11 vs. 19 ± 9 pA/pF; n = 4 to 6 neurons). Using bromodomain-containing protein 4-targeted antisense small interfering RNA to the complete Freund's adjuvant-treated rats, the authors demonstrated a reduction in the expression of bromodomain-containing protein 4 (0.68 ± 0.16 fold; n = 7), a reduction in thermal hyperalgesia (7.5 ± 1.5 s; n = 7), and a reduction in the increased voltage-gated sodium channel 1.7 currents (21 ± 4 pA/pF; n = 4 to 6 neurons). Complete Freund's adjuvant triggers enhanced bromodomain-containing protein 4 expression, ultimately leading to the enhanced excitability of nociceptive neurons and thermal hyperalgesia. This effect is

Zinc-decorated silica-coated magnetic nanoparticles for protein binding and controlled release.

Science.gov (United States)

Bele, Marjan; Hribar, Gorazd; Campelj, Stanislav; Makovec, Darko; Gaberc-Porekar, Vladka; Zorko, Milena; Gaberscek, Miran; Jamnik, Janko; Venturini, Peter

2008-05-01

The aim of this study was to be able to reversibly bind histidine-rich proteins to the surface of maghemite magnetic nanoparticles via coordinative bonding using Zn ions as the anchoring points. We showed that in order to adsorb Zn ions on the maghemite, the surface of the latter needs to be modified. As silica is known to strongly adsorb zinc ions, we chose to modify the maghemite nanoparticles with a nanometre-thick silica layer. This layer appeared to be thin enough for the maghemite nanoparticles to preserve their superparamagnetic nature. As a model the histidine-rich protein bovine serum albumin (BSA) was used. The release of the BSA bound to Zn-decorated silica-coated maghemite nanoparticles was analysed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We demonstrated that the bonding of the BSA to such modified magnetic nanoparticles is highly reversible and can be controlled by an appropriate change of the external conditions, such as a pH decrease or the presence/supply of other chelating compounds.

Soluble scute proteins of healthy and ill desert tortoises (Gopherus agassizii)

Science.gov (United States)

Homer, B.L.; Li, C.; Berry, K.H.; Denslow, N.D.; Jacobson, E.R.; Sawyer, R.H.; Williams, J.E.

2001-01-01

Objectives - To characterize protein composition of shell scute of desert tortoises and to determine whether detectable differences could be used to identify healthy tortoises from tortoises with certain illnesses. Animals - 20 desert tortoises. Procedures - Complete postmortem examinations were performed on all tortoises. Plastron scute proteins were solubilized, scute proteins were separated by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and proteins were analyzed, using densitometry. Two-dimensional immobilized pH gradient-PAGE (2D IPG-PAGE) and immunoblot analysis, using polyclonal antisera to chicken-feather ?? keratin and to alligator-scale ?? keratin, were conducted on representative samples. The 14-kd proteins were analyzed for amino acid composition. Results - The SDS-PAGE and densitometry revealed 7 distinct bands, each with a mean relative protein concentration of > 1 %, ranging from 8 to 47 kd, and a major protein component of approximately 14 kd that constituted up to 75% of the scute protein. The 2D IPG-PAGE revealed additional distinct 62-and 68-kd protein bands. On immunoblot analysis, the 14-, 32-, and 45-kd proteins reacted with both antisera. The 14-kd proteins had an amino acid composition similar to that of chicken ?? keratins. There was a substantial difference in the percentage of the major 14-kd proteins from scute of ill tortoises with normal appearing shells, compared with 14-kd proteins of healthy tortoises. Conclusions and Clinical Relevance - The major protein components of shell scute of desert tortoises have amino acid composition and antigenic features of ?? keratins. Scute protein composition may be altered in tortoises with certain systemic illnesses.

Calcium-dependent but calmodulin-independent protein kinase from soybean

International Nuclear Information System (INIS)

Harmon, A.C.; Putnam-Evans, C.; Cormier, M.J.

1987-01-01

A calcium-dependent protein kinase activity from suspension-cultured soybean cells (Glycine max L. Wayne) was shown to be dependent on calcium but not calmodulin. The concentrations of free calcium required for half-maximal histone H1 phosphorylation and autophosphorylation were similar (≥ 2 micromolar). The protein kinase activity was stimulated 100-fold by ≥ 10 micromolar-free calcium. When exogenous soybean or bovine brain calmodulin was added in high concentration (1 micromolar) to the purified kinase, calcium-dependent and -independent activities were weakly stimulated (≤ 2-fold). Bovine serum albumin had a similar effect on both activities. The kinase was separated from a small amount of contaminating calmodulin by sodium dodecyl sulfate polyacrylamide gel electrophoresis. After renaturation the protein kinase autophosphorylated and phosphorylated histone H1 in a calcium-dependent manner. Following electroblotting onto nitrocellulose, the kinase bound 45 Ca 2+ in the presence of KCl and MgCl 2 , which indicated that the kinase itself is a high-affinity calcium-binding protein. Also, the mobility of one of two kinase bands in SDS gels was dependent on the presence of calcium. Autophosphorylation of the calmodulin-free kinase was inhibited by the calmodulin-binding compound N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W-7), showing that the inhibition of activity by W-7 is independent of calmodulin. These results show that soybean calcium-dependent protein kinase represents a new class of protein kinase which requires calcium but not calmodulin for activity

Formation of a covalent complex between the terminal protein of pneumococcal bacteriophage Cp-1 and 5'-dAMP

International Nuclear Information System (INIS)

Garcia, P.; Hermoso, J.M.; Garcia, J.A.; Garcia, E.; Lopez, R.; Salas, M.

1986-01-01

Incubation of extracts of Cp-1-infected Streptococcus pneumoniae with [α- 32 P]dATP produced a labeled protein with the electrophoretic mobility of the Cp-1 terminal protein. The reaction product was resistant to treatment with micrococcal nuclease and sensitive to treatment with proteinase K. Incubation of the 32 P-labeled protein with 5 M piperidine for 4 h at 50 0 C released 5'-dAMP, indicating that a covalent complex between the terminal protein and 5'-dAMP was formed in vitro. When the four deoxynucleoside triphosphates were included in the reaction mixture, a labeled complex of slower electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gels than the terminal protein-dAMP complex was also found, indicating that the Cp-1 terminal protein-dAMP complex can be elongated and, therefore, that it is an initiation complex. Treatment of the 32 P-labeled terminal protein-dAMP complex with 5.8 M HCl at 110 0 C for 2 h yielded phosphothreonine. These results, together with the resistance of the terminal protein-DNA linkage to hydroxylamine, suggest that the Cp-1 terminal protein is covalently linked to the DNA through a phosphoester bond between L-threonine and 5'-dAMP, namely, a O-5'-deoxyadenylyl-L-threonine bond

Speciation of iodine-containing proteins in Nori seaweed by gel electrophoresis laser ablation ICP-MS.

Science.gov (United States)

Romarís-Hortas, V; Bianga, J; Moreda-Piñeiro, A; Bermejo-Barrera, P; Szpunar, J

2014-09-01

An analytical approach providing an insight into speciation of iodine in water insoluble fraction of edible seaweed (Nori) was developed. The seaweed, harvested in the Galician coast (Northwestern Spain), contained 67.7±1.3 μg g(-1) iodine of which 25% was water soluble and could be identifies as iodide. Extraction conditions of water insoluble residue using urea, NaOH, SDS and Triton X-100 were investigated. The protein pellets obtained in optimized conditions (after precipitation of urea extracts with acetone), were digested with trypsin and protease XIV. Size exclusion chromatography-ICP-MS of both enzymatic digests demonstrated the occurrence of iodoaminoacids putatively present in proteins. Intact proteins could be separated by gel electrophoresis after an additional extraction of the protein extract with phenol. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) with laser ablation ICP-MS detection of (127)I indicated the presence of iodine in protein bands corresponding to molecular masses of 110 kDa, 40 kDa, 27 kDa, 20 kDa and 10 kDa. 2D IEF-SDS PAGE with laser ablation ICP-MS (127)I imaging allowed the detection of 5 iodine containing protein spots in the alkaline pI range. Copyright © 2014 Elsevier B.V. All rights reserved.

Radiochemical identification of the kil gene product of bacteriophage lambda

International Nuclear Information System (INIS)

Greer, H.; Ausubel, F.M.

1979-01-01

The coliphage lambda kil gene product has been identified using a differential labeling technique . The kil gene polypeptide has a molecular weight of about 16,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Gel filtration of the kil protein indicates that it may exist as a tetramer in native form

Altered protein phosphorylation in sciatic nerve from rats with streptozocin-induced diabetes

International Nuclear Information System (INIS)

Schrama, L.H.; Berti-Mattera, L.N.; Eichberg, J.

1987-01-01

The effect of experimental diabetes on the phosphorylation of proteins in the rat sciatic nerve was studied. Nerves from animals made diabetic with streptozocin were incubated in vitro with [ 32 P]orthophosphate and divided into segments from the proximal to the distal end, and proteins from each segment were then separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The principal labeled species were the major myelin proteins, P0, and the basic proteins. After 6 wk of diabetes, the incorporation of isotope into these proteins rose as a function of distance along the nerve in a proximal to distal direction and was significantly higher at the distal end compared with incorporation into nerves from age-matched controls. The overall level of isotope uptake was similar in nerves from diabetic animals and weight-matched controls. The distribution of 32 P among proteins also differed in diabetic nerve compared with both control groups in that P0 and the small basic protein accounted for a greater proportion of total label incorporated along the entire length of nerve. In contrast to intact nerve, there was no significant difference in protein phosphorylation when homogenates from normal and diabetic nerve were incubated with [ 32 P]-gamma-ATP. The results suggest that abnormal protein phosphorylation, particularly of myelin proteins, is a feature of experimental diabetic neuropathy and that the changes are most pronounced in the distal portion of the nerve

A sulfhydryl-reactive ruthenium (II complex and its conjugation to protein G as a universal reagent for fluorescent immunoassays.

Directory of Open Access Journals (Sweden)

Jing-Tang Lin

Full Text Available To develop a fluorescent ruthenium complex for biosensing, we synthesized a novel sulfhydryl-reactive compound, 4-bromophenanthroline bis-2,2'-dipyridine Ruthenium bis (hexafluorophosphate. The synthesized Ru(II complex was crosslinked with thiol-modified protein G to form a universal reagent for fluorescent immunoassays. The resulting Ru(II-protein G conjugates were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. The emission peak wavelength of the Ru(II-protein G conjugate was 602 nm at the excitation of 452 nm which is similar to the spectra of the Ru(II complex, indicating that Ru(II-protein G conjugates still remain the same fluorescence after conjugation. To test the usefulness of the conjugate for biosensing, immunoglobulin G (IgG binding assay was conducted. The result showed that Ru(II-protein G conjugates were capable of binding IgG and the more cross-linkers to modify protein G, the higher conjugation efficiency. To demonstrate the feasibility of Ru(II-protein G conjugates for fluorescent immunoassays, the detection of recombinant histidine-tagged protein using the conjugates and anti-histidine antibody was developed. The results showed that the histidine-tagged protein was successfully detected with dose-response, indicating that Ru(II-protein G conjugate is a useful universal fluorescent reagent for quantitative immunoassays.

Effect of tooth bleaching agents on protein content and mechanical properties of dental enamel.

Science.gov (United States)

Elfallah, Hunida M; Bertassoni, Luiz E; Charadram, Nattida; Rathsam, Catherine; Swain, Michael V

2015-07-01

This study investigated the effect of two bleaching agents, 16% carbamide peroxide (CP) and 35% hydrogen peroxide (HP), on the mechanical properties and protein content of human enamel from freshly extracted teeth. The protein components of control and treated enamel were extracted and examined on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Marked reduction of the protein matrix and random fragmentation of the enamel proteins after bleaching treatments was found. The mechanical properties were analyzed with Vickers indentations to characterize fracture toughness, and nanoindentation to establish enamel hardness, elastic modulus and creep deformation. Results indicate that the hardness and elastic modulus of enamel were significantly reduced after treatment with CP and HP. After bleaching, the creep deformation at maximum load increased and the recovery upon unloading reduced. Crack lengths of CP and HP treated enamel were increased, while fracture toughness decreased. Additionally, the microstructures of fractured and indented samples were examined with field emission gun scanning electron microscopy (FEG-SEM) showing distinct differences in the fracture surface morphology between pre- and post-bleached enamel. In conclusion, tooth bleaching agents can produce detrimental effects on the mechanical properties of enamel, possibly as a consequence of damaging or denaturing of its protein components. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Identification of rat brain opioid (enkephalin) receptor by photoaffinity labeling

International Nuclear Information System (INIS)

Yeung, C.W.

1986-01-01

A photoreactive, radioactive enkephalin derivative was prepared and purified by high performance liquid chromatography. Rat brain and spinal cord plasma membranes were incubated with this radioiodinated photoprobe and were subsequently photolysed. Autoradiography of the sodium dodecyl sulfate gel electrophoresis of the solubilized and reduced membranes showed that a protein having an apparent molecular weight of 46,000 daltons was specifically labeled, suggesting that this protein may be the opioid (enkephalin) receptor

Periodontal and serum protein profiles in patients with rheumatoid arthritis treated with tumor necrosis factor inhibitor adalimumab.

Science.gov (United States)

Kobayashi, Tetsuo; Yokoyama, Tomoko; Ito, Satoshi; Kobayashi, Daisuke; Yamagata, Akira; Okada, Moe; Oofusa, Ken; Narita, Ichiei; Murasawa, Akira; Nakazono, Kiyoshi; Yoshie, Hiromasa

2014-11-01

Tumor necrosis factor (TNF)-α inhibitor has been shown to affect the periodontal condition of patients with rheumatoid arthritis (RA). The aim of the present study is to assess the effect of a fully humanized anti-TNF-α monoclonal antibody, adalimumab (ADA), on the periodontal condition of patients with RA and to compare serum protein profiles before and after ADA therapy. The study participants consisted of 20 patients with RA treated with ADA. Clinical periodontal and rheumatologic parameters and serum cytokine levels were evaluated at baseline and 3 months later. Serum protein spot volume was examined with two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins with significant difference in abundance before and after ADA therapy were found and identified using mass spectrometry and protein databases. The patients showed a significant decrease in gingival index (P = 0.002), bleeding on probing (P = 0.003), probing depth (P = 0.002), disease activity score including 28 joints using C-reactive protein (P protein spots obtained, nine spots were significantly decreased in abundance at reassessment, corresponding to complement factor H, phospholipase D, serum amyloid A, complement component 4, and α-1-acid glycoprotein (P periodontal condition of patients with RA, which might be related to differences in serum protein profiles before and after ADA therapy.

Two proteins with reverse transcriptase activities associated with hepatitis B virus-like particles

International Nuclear Information System (INIS)

Bavand, M.R.; Laub, O.

1988-01-01

Recent studies suggest that hepatitis B virus (HBV), despite being a DNA virus, replicates via an RNA intermediate. The HBV life cycle is therefore a permuted version of the RNA retroviral life cycle. Sequence homology between retroviral reverse transcriptase and the putative HBV polymerase gene product suggests the presence of an HBV reverse transcriptase. As yet, there has been no direct evidence that reverse transcriptase activity is present in the viral particle. The authors used activity gel analysis to detect the in situ catalytic activities of DNA polymerases after sodium dodecyl sulfate-polyacrylamide gel electrophorsis. These studies demonstrated that HBV-like particles secreted by a differentiated human hepatoma cell line tranfected with genomic HBV DNA contain two major polymerase activities which migrate as ∼90- and ∼70-kilodalton (kDa) proteins. This demonstrated, for the first time, that HBV-like particles contain a novel DNA polymerase-reverse transcriptase activity. Furthermore, they propose that the 70-kDa reverse transcriptase may be produced by proteolytic self-cleavage of the 90-kDa precursor protein

Identification of Important Process Variables for Fiber Spinning of Protein Nanotubes Generated from Waste Materials

Science.gov (United States)

2012-01-11

PEEK Polyether ether ketone POM Polarized optical microscopy PT Phosphate-Tris (spinning buffer) SDS-PAGE Sodium dodecyl sulfate...the form of a gas such as water, ammonia, carbon monoxide, hydrogen cyanide , carbon dioxide and nitrogen. Carbonization is carried out at... steel . Therefore, spider silk fibers possess the desirable mechanical properties for lightweight, high-performance fiber, and composite applications

Association of lipids with integral membrane surface proteins of Mycoplasma hyorhinis

International Nuclear Information System (INIS)

Bricker, T.M.; Boyer, M.J.; Keith, J.; Watson-McKown, R.; Wise, K.S.

1988-01-01

Triton X-114 (TX-114)-phase fractionation was used to identify and characterize integral membrane surface proteins of the wall-less procaryote Mycoplasma hyorhinis GDL. Phase fractionation of mycoplasmas followed by analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed selective partitioning of approximately 30 [ 35 S]methionine-labeled intrinsic membrane proteins into the TX-114 phase. Similar analysis of [ 3 H]palmitate-labeled cells showed that approximately 20 proteins of this organism were associated with lipid, all of which also efficiently partitioned as integral membrane components into the detergent phase. Immunoblotting and immunoprecipitation of TX-114-phase proteins from 125 I-surface-labeled cells with four monoclonal antibodies to distinct surface epitopes of M. hyorhinis identified surface proteins p120, p70, p42, and p23 as intrinsic membrane components. Immunoprecipitation of [ 3 H]palmitate-labeled TX-114-phase proteins further established that surface proteins p120, p70, and p23 (a molecule that mediates complement-dependent mycoplasmacidal monoclonal antibody activity) were among the lipid-associated proteins of this organism. Two of these proteins, p120 and p123, were acidic (pI less than or equal to 4.5), as shown by two-dimensional isoelectric focusing. This study established that M. hyorhinis contains an abundance of integral membrane proteins tightly associated with lipids and that many of these proteins are exposed at the external surface of the single limiting plasma membrane. Monoclonal antibodies are reported that will allow detailed analysis of the structure and processing of lipid-associated mycoplasma proteins

Identification of a Protein with Antioxidant Activity that is Important for the Protection against Beer Ageing

Science.gov (United States)

Wu, Ming J.; Clarke, Frank M.; Rogers, Peter J.; Young, Paul; Sales, Narelle; O’Doherty, Patrick J.; Higgins, Vincent J.

2011-01-01

This study was carried out with fresh Australian lager beer which was sampled directly off the production line, the same samples aged for 12 weeks at 30 °C, and the vintage beer which was kept at 20 °C for 5 years. Characteristic Australian lager flavour was maintained in the fresh and vintage beers but was lost in the aged beer. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and free thiol group labelling analyses of beer proteins found that this flavour stability correlated with the presence of an unknown 10 kilodaltons (kDa) protein with a higher level of free thiols. The protein was purified by size-exclusion chromatography, then peptide sequencing and database matching identified it as the barley lipid transfer protein (LTP1). Further characterisation using diphenylpicrylhydrazyl (DPPH) free radical scavenging and a Saccharomyces cerevisiae-based antioxidant screening assay demonstrated that the LTP1 protein was active in DPPH reduction and antioxidant activity. The absence of free thiol in the aged beer indicates that the thiol functional groups within the LTP1 protein were saturated and suggests that it is important in the flavour stability of beer by maintaining reduction capacity during the ageing process. PMID:22016646

Assessment of the Antioxidant Activity of Silybum marianum Seed Extract and Its Protective Effect against DNA Oxidation, Protein Damage and Lipid Peroxidation

Directory of Open Access Journals (Sweden)

Aynur Serçe

2016-01-01

Full Text Available Antioxidant properties of ethanol extract of Silybum marianum (milk thistle seeds was investigated. We have also investigated the protein damage activated by oxidative Fenton reaction and its prevention by Silybum marianum seed extract. Antioxidant potential of Silybum marianum seed ethanol extract was measured using diff erent in vitro methods, such as lipid peroxidation, 1,1–diphenyl–2–picrylhydrazyl (DPPH and ferric reducing power assays. The extract significantly decreased DNA damage caused by hydroxyl radicals. Protein damage induced by hydroxyl radicals was also effi ciently inhibited, which was confirmed by the presence of protein damage markers, such as protein carbonyl formation and by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE. The present study shows that milk thistle seeds have good DPPH free radical scavenging activity and can prevent lipid peroxidation. Therefore, Silybum marianum can be used as potentially rich source of antioxidants and food preservatives. The results suggest that the seeds may have potential beneficial health effects providing opportunities to develop value-added products.

Role of additives; sodium dodecyl sulphate and manganese chloride on morphology of Zn{sub 1−x}Mn{sub x}O nanoparticles and their photoluminescence properties

Energy Technology Data Exchange (ETDEWEB)

Pandey, Gajanan, E-mail: pandeygajanan@rediffmail.com [Department of Applied Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow 226025, U.P. (India); Dixit, Supriya; Shrivastava, A.K. [School of Studies in Physics, Jiwaji University, Gwalior 474011, M.P. (India)

2014-10-15

In the present study Zn{sub 1−x}Mn{sub x}O (x = 0, 0.05 and 0.1) nanoparticles (NPs) have been synthesised in aqueous solution phase at mild reaction temperature 100 °C in moderate alkaline medium (pH = 9.5), and the role of external additives; like sodium dodecyl sulphate and manganese chloride on the morphology and size of the products has been explored on the basis of transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectral analyses data. ZnO hexagonal nano-plates, core–shell like spherical/ellipsoidal Zn{sub 0.95}Mn{sub 0.05}O structures and thin sheets, thorn/needle mixed shaped Zn{sub 0.9}Mn{sub 0.1}O structures have been observed in TEM and SEM images. Zn(OH){sub 2} formed in moderate alkaline medium, converted to Zn(II) hydroxo complex ions on dissolution, which further recrystallizes to produce wurtzite ZnO at 100 °C. From XRD and EDX analysis, successful doping of Mn{sup 2+} ions at the Zn{sup 2+} sites in ZnO host has been proved. In the photoluminescence spectra, the observed blue shifts in NBE peaks and decrease of emissions intensity on Mn doping have thoroughly been discussed in the present investigation. - Highlights: • Zn{sub 1−x}Mn{sub x}O NPs have been prepared in aqueous solution at mild temperature 100 °C. • Shifts in XRD lines and NBE peaks in PL spectra proved doping of Mn{sup 2+} in the ZnO. • ZnO is formed via dissolution–recrystallization of ε-Zn(OH){sub 2}–ZnO. • Additives SDS and MnCl{sub 2}·4H{sub 2}O play important role on morphology of Zn{sub 1−x}Mn{sub x}O NPs. • Mn contents increased extrinsic defects, which decreased intensity of PL spectra.

Potential Health Effects of Enzymatic Protein Hydrolysates from Chlorella vulgaris

Directory of Open Access Journals (Sweden)

Mahsa Sedighi

2016-06-01

Full Text Available Background and Objective: Chlorella vulgaris is a multi-cellular edible algal species with abundant proteins. Extraction of high value protein fractions for pharmaceutical and nutritional applications can significantly increase the commercial value of microalga biomasses. There is no known report on the anticancer peptides derived from the Chlorella vulgaris abundant protein.Materials and Methods: This study examined the antimicrobial and anticancer effects of peptides from a hydrolyzed Chlorella vulgaris protein with 62 kDa molecular weight. Protein hydrolysis was done by pepsin as a gastrointestinal protease, and was monitored through protein content measurement, sodium dodecyl sulfate polyacrylamide gel electrophoresis, and high performance liquidchromatography measurements. Inhibitory effect of the produced peptides on Escherichia coli cells and breast cancer cell lines was assayed.Results and Conclusion: Hydrolyzed peptides induced a decrease of about 34.1% in the growth of Escherichia coli, and the peptides of 3 to 5 kDa molecular weight had strong impact on the viability of breast cancer cells with IC50 value of 50 μg μl-1. The peptide fractions demonstrating antimicrobial and anti-cancer activities have the potential for use as functional food ingredients for health benefits. These results demonstrate that inexpensive algae proteinscould be a new alternative to produce anticancer peptides.Conflict of interest: The authors declare that there is no conflict of interest.

Rescuing Those Left Behind: Recovering and Characterizing Underdigested Membrane and Hydrophobic Proteins To Enhance Proteome Measurement Depth.

Science.gov (United States)

Giannone, Richard J; Wurch, Louie L; Podar, Mircea; Hettich, Robert L

2015-08-04

The marine archaeon Nanoarchaeum equitans is dependent on direct physical contact with its host, the hyperthermophile Ignicoccus hospitalis. As this interaction is thought to be membrane-associated, involving a myriad of membrane-anchored proteins, proteomic efforts to better characterize this difficult to analyze interface are paramount to uncovering the mechanism of their association. By extending multienzyme digestion strategies that use sample filtration to recover underdigested proteins for reprocessing/consecutive proteolytic digestion, we applied chymotrypsin to redigest the proteinaceous material left over after initial proteolysis with trypsin of sodium dodecyl sulfate (SDS)-extracted I. hospitalis-N. equitans proteins. Using this method, we show that proteins with increased hydrophobic character, including membrane proteins with multiple transmembrane helices, are enriched and recovered in the underdigested fraction. Chymotryptic reprocessing provided significant sequence coverage gains in both soluble and hydrophobic proteins alike, with the latter benefiting more so in terms of membrane protein representation. These gains were despite a large proportion of high-quality peptide spectra remaining unassigned in the underdigested fraction suggesting high levels of protein modification on these often surface-exposed proteins. Importantly, these gains were achieved without applying extensive fractionation strategies usually required for thorough characterization of membrane-associated proteins and were facilitated by the generation of a distinct, complementary set of peptides that aid in both the identification and quantitation of this important, under-represented class of proteins.

Isolation of eukaryotic ribosomal proteins. Purification and characterization of 60 S ribosomal subunit proteins L3, L6, L7', L8, L10, L15, L17, L18, L19, L23', L25, L27', L28, L29, L31, L32, L34, L35, L36, L36', and L37'.

Science.gov (United States)

Tsurugi, K; Collatz, E; Todokoro, K; Wool, I G

1977-06-10

The proteins of the large subunit of rat liver ribosomes were separated into seven groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Twenty-one proteins (L3, L6, L7', L8, L10, L15, L17, L18, L19, L23', L25, L27', L28, L29, L31, L32, L34, L35, L36, L36', and L37') were isolated from three groups (C60, E60, and F60) by ion exchange chromatography on carboxymethycellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.3 to 25 mg. Nine of the proteins (L6, L8, L18, L27', L28, L29, L34, L36, and L36') had no detectable contamination: the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.

Modifying a standard method allows simultaneous extraction of RNA and protein, enabling detection of enzymes in the rat retina with low expressions and protein levels.

Science.gov (United States)

Agardh, Elisabet; Gustavsson, Carin; Hagert, Per; Nilsson, Marie; Agardh, Carl-David

2006-02-01

The aim of the study was to evaluate messenger RNA and protein expression in limited amounts of tissue with low protein content. The Chomczynski method was used for simultaneous extraction of RNA, and protein was modified in the protein isolation step. Template mass and cycling time for the complementary DNA synthesis step of real-time reverse transcription-polymerase chain reaction (RT-PCR) for analysis of catalase, copper/zinc superoxide dismutase, manganese superoxide dismutase, the catalytic subunit of glutamylcysteine ligase, glutathione peroxidase 1, and the endogenous control cyclophilin B (CypB) were optimized before PCR. Polymerase chain reaction accuracy and efficacy were demonstrated by calculating the regression (R2) values of the separate amplification curves. Appropriate antibodies, blocking buffers, and running conditions were established for Western blot, and protein detection and multiplex assays with CypB were performed for each target. During the extraction procedure, the protein phase was dissolved in a modified washing buffer containing 0.1% sodium dodecyl sulfate, followed by ultrafiltration. Enzyme expression on real-time RT-PCR was accomplished with high reliability and reproducibility (R2, 0.990-0.999), and all enzymes except for glutathione peroxidase 1 were detectable in individual retinas on Western blot. Western blot multiplexing with CypB was possible for all targets. In conclusion, connecting gene expression directly to protein levels in the individual rat retina was possible by simultaneous extraction of RNA and protein. Real-time RT-PCR and Western blot allowed accurate detection of retinal protein expressions and levels.

Multi-technique approach on the interaction between sugar-based surfactant n-dodecyl β-D-maltoside and bovine serum albumin

Energy Technology Data Exchange (ETDEWEB)

Ali, Mohd Sajid, E-mail: smsajidali@gmail.com; Al-Lohedan, Hamad A.

2016-01-15

A multi-technique approach which comprises various basic and advanced techniques, such as surface tensiometry, synchronous, intrinsic and extrinsic fluorescence, far and near-UV circular dichroism (CD), dynamic light scattering (DLS), Fourier transform infra-red (FTIR) and UV–visible spectrophotometries was applied to understand the interaction between biocompatible sugar-based surfactant n-dodecyl β-D-maltoside (C{sub 12}G{sub 2}) and bovine serum albumin (BSA). Formation of complex between surfactant and protein was initially confirmed by surface tension and UV absorption spectroscopy. The presence of BSA shifted the critical micelle concentration of the surfactant at higher concentration and in a similar way the UV spectrum of the BSA was altered by addition of small amount of surfactant. The interfacial properties of the complex such as π{sub cmc} (the surface pressure at the cmc), Γ{sub max} (the maximum surface excess) and A{sub min} (the minimum surface area per molecule) were also calculated. Addition of surfactant causes the quenching of BSA fluorescence and a large blue-shift at both excitation wavelengths (280 and 295 nm) owing to the hydrophobic interaction between surfactant and protein. The quenching took place via static mechanism. Extrinsic fluorescence of 1-anilino-8-naphthalene sulfonate (ANS) increased as a result of the unfolding of the protein. The secondary and tertiary structure of BSA also influenced as revealed by the collective information obtained by far-UV CD, near-UV CD and FTIR spectroscopies. The increase in the size of the complex as a results of the partial unfolding was also confirmed by DLS measurements as well as resonance Rayleigh scattering (RRS). - Highlights: • In the presence of BSA cmc of sugar surfactant n-dodecyl β-D-maltoside increased due to the binding of BSA with surfactant. • The binding of the surfactant leads to the partial unfolding of BSA. • The conformation of BSA predominately remains the α-helical.

Purification and characterization of a novel 1,3- propanediol ...

African Journals Online (AJOL)

A novel 1,3-propanediol oxidoreductase (YqhD-1) found in Klebsiella oxytoca M5al was purified to homogeneity with a his-tag on a Ni-NTA column. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified protein showed a molecular weight of 42 kDa. When YqhD-1 was tested as a ...

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

Science.gov (United States)

Mune Mune, Martin Alain; Minka, Samuel René

2017-06-01

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

Two-dimensional chromatographic analysis using three second-dimension columns for continuous comprehensive analysis of intact proteins.

Science.gov (United States)

Zhu, Zaifang; Chen, Huang; Ren, Jiangtao; Lu, Juan J; Gu, Congying; Lynch, Kyle B; Wu, Si; Wang, Zhe; Cao, Chengxi; Liu, Shaorong

2018-03-01

We develop a new two-dimensional (2D) high performance liquid chromatography (HPLC) approach for intact protein analysis. Development of 2D HPLC has a bottleneck problem - limited second-dimension (second-D) separation speed. We solve this problem by incorporating multiple second-D columns to allow several second-D separations to be proceeded in parallel. To demonstrate the feasibility of using this approach for comprehensive protein analysis, we select ion-exchange chromatography as the first-dimension and reverse-phase chromatography as the second-D. We incorporate three second-D columns in an innovative way so that three reverse-phase separations can be performed simultaneously. We test this system for separating both standard proteins and E. coli lysates and achieve baseline resolutions for eleven standard proteins and obtain more than 500 peaks for E. coli lysates. This is an indication that the sample complexities are greatly reduced. We see less than 10 bands when each fraction of the second-D effluents are analyzed by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE), compared to hundreds of SDS-PAGE bands as the original sample is analyzed. This approach could potentially be an excellent and general tool for protein analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Nonelectrophoretic bidirectional transfer of a single SDS-PAGE gel with multiple antigens to obtain 12 immunoblots.

Science.gov (United States)

Kurien, Biji T; Scofield, R Hal

2009-01-01

Protein blotting is an invaluable technique in immunology to detect and characterize proteins of low abundance. Proteins resolved on sodium dodecyl sulfate (SDS) polyacrylamide gels are normally transferred electrophoretically to adsorbent membranes such as nitrocellulose or polyvinylidene diflouride membranes. Here, we describe the nonelectrophroretic transfer of the Ro 60 (or SSA) autoantigen, 220- and 240-kD spectrin antigens, and prestained molecular weight standards from SDS polyacrylamide gels to obtain up to 12 immunoblots from a single gel and multiple sera.

Sodium Channel (Dys)Function and Cardiac Arrhythmias

NARCIS (Netherlands)

Remme, Carol Ann; Bezzina, Connie R.

2010-01-01

P>Cardiac voltage-gated sodium channels are transmembrane proteins located in the cell membrane of cardiomyocytes. Influx of sodium ions through these ion channels is responsible for the initial fast upstroke of the cardiac action potential. This inward sodium current thus triggers the initiation

Characterization of plasma menbrane polypeptides of trypanosoma from bats Caracterização de polipeptídeos de membrana plasmática de tripanosomas de morcegos

OpenAIRE

R. T. Pinho; Giovanni de Simone

1989-01-01

Cell surface proteins of Trypanosoma dionisii, Trypanosoma vespertilionis and Trypanosoma sp. (M238) were radiodinated and their distribution both in the detergent-poor (DPP) and dertergent-enriched phase (DRP) was studied using a phase separation technique in Triton X-114 as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE). Significant differences were observed in the proteins present in the DRP when the three species of trypanosoma were compared. Two major ba...

Characterization of plasma menbrane polypeptides of trypanosoma from bats

OpenAIRE

Pinho,R. T.; Simone,Giovanni de

1989-01-01

Cell surface proteins of Trypanosoma dionisii, Trypanosoma vespertilionis and Trypanosoma sp. (M238) were radiodinated and their distribution both in the detergent-poor (DPP) and dertergent-enriched phase (DRP) was studied using a phase separation technique in Triton X-114 as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE). Significant differences were observed in the proteins present in the DRP when the three species of trypanosoma were compared. Two major ba...

Sodium alginate microneedle arrays mediate the transdermal delivery of bovine serum albumin.

Directory of Open Access Journals (Sweden)

Yusuf K Demir

Full Text Available BACKGROUND: The "poke and release" strategy for the delivery of macromolecules using polymeric microneedle (MN is of great importance because it eliminates microneedle reuse, the risks of biohazardous sharps and cross contamination, and it requires no special disposal mechanism. The main objective of this study was the determination of the stability and delivery of bovine serum albumin (BSA that was transported across human skin via sodium alginate (SA microneedle arrays (MNs and SA needle free patches using two different analytical methods. METHODOLOGY AND FINDINGS: The capability of two analytical methods, the bicinchoninic acid (BCA assay and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE, to precisely detect and quantify BSA within different types of polymeric MNs was assessed. The ex vivo protein release of BSA across dermatomed human abdominal skin from 10 w/w SA MNs was compared to that from needle-free patches using Franz diffusion cells. The developed applicator was mechanically characterized using a Texture Analyzer. The patch mold and its components were fabricated using a rapid prototyping machine. CONCLUSIONS/SIGNIFICANCE: The BCA method was able to precisely detect BSA that had been loaded into SA MNs. However, the use of SDS-PAGE as the analytical method resulted in significantly different amounts of BSA recovered from differently conditioned polymeric MNs. The permeation of BSA across dermatomed human abdominal skin by SA MNs, which were composed of 100 pyramidal needles, increased by approximately 15.4 fold compared to the permeation obtained with SA needle-free patches. The ease of use of the applicator during the release studies was also demonstrated, as was its mechanical characterization.

Rapid directed evolution of stabilized proteins with cellular high-throughput encapsulation solubilization and screening (CHESS).

Science.gov (United States)

Yong, K J; Scott, D J

2015-03-01

Directed evolution is a powerful method for engineering proteins towards user-defined goals and has been used to generate novel proteins for industrial processes, biological research and drug discovery. Typical directed evolution techniques include cellular display, phage display, ribosome display and water-in-oil compartmentalization, all of which physically link individual members of diverse gene libraries to their translated proteins. This allows the screening or selection for a desired protein function and subsequent isolation of the encoding gene from diverse populations. For biotechnological and industrial applications there is a need to engineer proteins that are functional under conditions that are not compatible with these techniques, such as high temperatures and harsh detergents. Cellular High-throughput Encapsulation Solubilization and Screening (CHESS), is a directed evolution method originally developed to engineer detergent-stable G proteins-coupled receptors (GPCRs) for structural biology. With CHESS, library-transformed bacterial cells are encapsulated in detergent-resistant polymers to form capsules, which serve to contain mutant genes and their encoded proteins upon detergent mediated solubilization of cell membranes. Populations of capsules can be screened like single cells to enable rapid isolation of genes encoding detergent-stable protein mutants. To demonstrate the general applicability of CHESS to other proteins, we have characterized the stability and permeability of CHESS microcapsules and employed CHESS to generate thermostable, sodium dodecyl sulfate (SDS) resistant green fluorescent protein (GFP) mutants, the first soluble proteins to be engineered using CHESS. © 2014 Wiley Periodicals, Inc.

Congenital deficiency of two polypeptide subunits of the iron-protein fragment of mitochondrial complex I.

Science.gov (United States)

Moreadith, R W; Cleeter, M W; Ragan, C I; Batshaw, M L; Lehninger, A L

1987-02-01

Recently, we described a patient with severe lactic acidosis due to congenital complex I (NADH-ubiquinone oxidoreductase) deficiency. We now report further enzymatic and immunological characterizations. Both NADH and ferricyanide titrations of complex I activity (measured as NADH-ferricyanide reductase) were distinctly altered in the mitochondria from the patient's tissues. In addition, antisera against complex I immunoprecipitated NADH-ferricyanide reductase from the control but not the patient's mitochondria. However, immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of complex I polypeptides demonstrated that the majority of the 25 polypeptides comprising complex I were present in the affected mitochondria. A more detailed analysis using subunit selective antisera against the main polypeptides of the iron-protein fragments of complex I revealed a selective absence of the 75- and 13-kD polypeptides. These findings suggest that the underlying basis for this patient's disease was a congenital deficiency of at least two polypeptides comprising the iron-protein fragment of complex I, which resulted in the inability to correctly assemble a functional enzyme complex.

Denaturation of proteins by surfactants studied by the Taylor dispersion analysis.

Directory of Open Access Journals (Sweden)

Aldona Jelińska

Full Text Available We showed that the Taylor Dispersion Analysis (TDA is a fast and easy to use method for the study of denaturation proteins. We applied TDA to study denaturation of β-lactoglobulin, transferrin, and human insulin by anionic surfactant sodium dodecyl sulfate (SDS. A series of measurements at constant protein concentration (for transferrin was 1.9 x 10-5 M, for β- lactoglobulin was 7.6 x 10-5 M, and for insulin was 1.2 x 10-4 M and varying SDS concentrations were carried out in the phosphate-buffered saline (PBS. The structural changes were analyzed based on the diffusion coefficients of the complexes formed at various surfactant concentrations. The concentration of surfactant was varied in the range from 1.2 x 10-4 M to 8.7 x 10-2 M. We determined the minimum concentration of the surfactant necessary to change the native conformation of the proteins. The minimal concentration of SDS for β-lactoglobulin and transferrin was 4.3 x 10-4 M and for insulin 2.3 x 10-4 M. To evaluate the TDA as a novel method for studying denaturation of proteins we also applied other methods i.e. electronic circular dichroism (ECD and dynamic light scattering (DLS to study the same phenomenon. The results obtained using these methods were in agreement with the results from TDA.

Rab27a regulates epithelial sodium channel (ENaC) activity through synaptotagmin-like protein (SLP-5) and Munc13-4 effector mechanism

International Nuclear Information System (INIS)

Saxena, Sunil K.; Horiuchi, Hisanori; Fukuda, Mitsunori

2006-01-01

Liddle's syndrome (excessive absorption of sodium ions) and PHA-1 (pseudohypoaldosteronism type 1) with decreased sodium absorption are caused by the mutations in the amiloride-sensitive epithelial sodium channel ENaC. Rab proteins are small GTPases involved in vesicle transport, docking, and fusion. Earlier, we reported that Rab27a inhibits ENaC-mediated currents through protein-protein interaction in HT-29 cells. We hereby report that Rab27a-dependent inhibition is associated with the GTP/GDP status as constitutively active or GTPase-deficient mutant Q78L inhibits amiloride-sensitive currents whereas GDP-locked inactive mutant T23N showed no effect. In order to further explore the molecular mechanism of this regulation, we performed competitive assays with two Rab27a-binding proteins: synaptotagmin-like protein (SLP-5) and Munc13-4 (a putative priming factor for exocytosis). Both proteins eliminate negative modulation of Rab27a on ENaC function. The SLP-5 reversal of Rab27a effect was restricted to C-terminal C2A/C2B domains assigned for putative phospholipids-binding function while the Rab27a-binding SHD motif imparted higher inhibition. The ENaC-mediated currents remain unaffected by Rab27a though SLP-5 appears to strongly bind it. The immunoprecipitation experiments suggest that in the presence of excessive Munc13-4 and SLP-5 proteins, Rab27a interaction with ENaC is diminished. Munc13-4 and SLP-5 limit the Rab27a availability to ENaC, thus minimizing its effect on channel function. These observations decisively prove that Rab27a inhibits ENaC function through a complex mechanism that involves GTP/GDP status, and protein-protein interactions involving Munc13-4 and SLP-5 effector proteins

Ca(2+)-calmodulin-dependent phosphorylation of islet secretory granule proteins

International Nuclear Information System (INIS)

Watkins, D.T.

1991-01-01

The effect of Ca2+ and calmodulin on phosphorylation of islet secretory granule proteins was studied. Secretory granules were incubated in a phosphorylation reaction mixture containing [32P]ATP and test reagents. The 32P-labeled proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the 32P content was visualized by autoradiography, and the relative intensities of specific bands were quantitated. When the reaction mixture contained EGTA and no added Ca2+, 32P was incorporated into two proteins with molecular weights of 45,000 and 13,000. When 10(-4) M Ca2+ was added without EGTA, two additional proteins (58,000 and 48,000 Mr) were phosphorylated, and the 13,000-Mr protein was absent. The addition of 2.4 microM calmodulin markedly enhanced the phosphorylation of the 58,000- and 48,000-Mr proteins and resulted in the phosphorylation of a major protein whose molecular weight (64,000 Mr) is identical to that of one of the calmodulin binding proteins located on the granule surface. Calmodulin had no effect on phosphorylation in the absence of Ca2+ but was effective in the presence of calcium between 10 nM and 50 microM. Trifluoperazine and calmidazolium, calmodulin antagonists, produced a dose-dependent inhibition of the calmodulin effect. 12-O-tetradecanoylphorbol 13-acetate, a phorbol ester that activates protein kinase C, produced no increase in phosphorylation, and 1-(5-isoquinoline sulfonyl)-2-methyl piperazine dihydrochloride, an inhibitor of protein kinase C, had no effect. These results indicate that Ca(2+)-calmodulin-dependent protein kinases and endogenous substrates are present in islet secretory granules

Brown pigment formation in heated sugar-protein mixed suspensions containing unmodified and peptically modified whey protein concentrates.

Science.gov (United States)

Rongsirikul, Narumol; Hongsprabhas, Parichat

2016-01-01

Commercial whey protein concentrate (WPC) was modified by heating the acidified protein suspensions (pH 2.0) at 80 °C for 30 min and treating with pepsin at 37 °C for 60 min. Prior to spray-drying, such modification did not change the molecular weights (MWs) of whey proteins determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After spray-drying the modified whey protein concentrate with trehalose excipient (MWPC-TH), it was found that the α-lactalbumin (α-La) was the major protein that was further hydrolyzed the most. The reconstituted MWPC-TH contained β-lactoglobulin (β-Lg) as the major protein and small molecular weight (MW) peptides of less than 6.5 kDa. The reconstituted MWPC-TH had higher NH2 group, Trolox equivalent antioxidant capacity (TEAC), lower exposed aromatic ring and thiol (SH) contents than did the commercial WPC. Kinetic studies revealed that the addition of MWPC-TH in fructose-glycine solution was able to reduce brown pigment formation in the mixtures heated at 80 to 95 °C by increasing the activation energy (Ea) of brown pigment formation due to the retardation of fluoresced advanced glycation end product (AGEs) formation. The addition of MWPC to reducing sugar-glycine/commercial WPC was also able to lower brown pigment formation in the sterilized (121 °C, 15 min) mixed suspensions containing 0.1 M reducing sugar and 0.5-1.0 % glycine and/or commercial (P < 0.05). It was demonstrated that the modification investigated in this study selectively hydrolyzed α-La and retained β-Lg for the production of antibrowning whey protein concentrate.

Proteomic Investigation of Protein Profile Changes and Amino Acid Residue Level Modification in Cooked Lamb Meat: The Effect of Boiling.

Science.gov (United States)

Yu, Tzer-Yang; Morton, James D; Clerens, Stefan; Dyer, Jolon M

2015-10-21

Hydrothermal treatment (heating in water) is a common method of general food processing and preparation. For red-meat-based foods, boiling is common; however, how the molecular level effects of this treatment correlate to the overall food properties is not yet well-understood. The effects of differing boiling times on lamb meat and the resultant cooking water were here examined through proteomic evaluation. The longer boiling time was found to result in increased protein aggregation involving particularly proteins such as glyceraldehyde-3-phosphate dehydrogenase, as well as truncation in proteins such as in α-actinin-2. Heat-induced protein backbone cleavage was observed adjacent to aspartic acid and asparagine residues. Side-chain modifications of amino acid residues resulting from the heating, including oxidation of phenylalanine and formation of carboxyethyllysine, were characterized in the cooked samples. Actin and myoglobin bands from the cooked meat per se remained visible on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, even after significant cooking time. These proteins were also found to be the major source of observed heat-induced modifications. This study provides new insights into molecular-level modifications occurring in lamb meat proteins during boiling and a protein chemistry basis for better understanding the effect of this common treatment on the nutritional and functional properties of red-meat-based foods.

Sodium Solute Symporter and Cadherin Proteins Act as Bacillus thuringiensis Cry3Ba Toxin Functional Receptors in Tribolium castaneum*

Science.gov (United States)

Contreras, Estefanía; Schoppmeier, Michael; Real, M. Dolores; Rausell, Carolina

2013-01-01

Understanding how Bacillus thuringiensis (Bt) toxins interact with proteins in the midgut of susceptible coleopteran insects is crucial to fully explain the molecular bases of Bt specificity and insecticidal action. In this work, aminopeptidase N (TcAPN-I), E-cadherin (TcCad1), and sodium solute symporter (TcSSS) have been identified by ligand blot as putative Cry3Ba toxin-binding proteins in Tribolium castaneum (Tc) larvae. RNA interference knockdown of TcCad1 or TcSSS proteins resulted in decreased susceptibility to Cry3Ba toxin, demonstrating the Cry toxin receptor functionality for these proteins. In contrast, TcAPN-I silencing had no effect on Cry3Ba larval toxicity, suggesting that this protein is not relevant in the Cry3Ba toxin mode of action in Tc. Remarkable features of TcSSS protein were the presence of cadherin repeats in its amino acid sequence and that a TcSSS peptide fragment containing a sequence homologous to a binding epitope found in Manduca sexta and Tenebrio molitor Bt cadherin functional receptors enhanced Cry3Ba toxicity. This is the first time that the involvement of a sodium solute symporter protein as a Bt functional receptor has been demonstrated. The role of this novel receptor in Bt toxicity against coleopteran insects together with the lack of receptor functionality of aminopeptidase N proteins might account for some of the differences in toxin specificity between Lepidoptera and Coleoptera insect orders. PMID:23645668

Partial purification and identification of the thrombozane A2/prostaglandin H2 receptor protein in human platelets

International Nuclear Information System (INIS)

Lim, C.T.; Kattelman, E.J.; Arora, S.K.; Venton, D.L.; Le Breton, G.C.

1986-01-01

The thromboxane A 2 /prostaglandin H 2 (TXA 2 /PGH 2 ) receptor antagonist [ 3 H]-13-azaprostanoic acid (13-APA) was used to identify and purify the platelet TXA 2 /PGH 2 receptor protein. Optimal solubilization of the 13-APA binding protein was achieved by extraction with 3-[(3-cholamidopropyl)dimethyl-ammonio]-1-propanesulfonate (CHAPS) detergent. Preliminary purification of the crude solubilized membrane fraction was performed by gel filtration chromatography using a Sepharose 4B column. Further purification was accomplished by high performance liquid chromatography (HPLC) using a Synchropak GPC-500 column. The HPLC protein profile revealed two protein peaks, only one of which was enriched in [ 3 H]-13-APA. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of this peak revealed two bands with molecular weights of 65,000 and 60,000 daltons. In binding studies using the 60,000 dalton-enriched subfraction, unlabelled 13-APA, the TXA 2 /PGH 2 mimetic U46619 and the TXA 2 /PGH 2 antagonist SQ 29,548 all competed for [ 3 H]-13-APA binding whereas TXB 2 did not compete for binding. Heat denaturation of this subfraction resulted in a complete loss of binding activity. These findings indicate that a protein of approximately 60,000 daltons represents the human platelet TXA 2 /PGH 2 receptor

Use of electrophoretically separated serum protein fractions for the diagnosis of cardiomyopathy

International Nuclear Information System (INIS)

Siddiqui, Z.H.; Cheema, A.M.

2011-01-01

In an investigation of molecular pathogenesis in cardiovascular diseases, the blood samples of the patients diagnosed for cardiomyopathy (CMP) were obtained from the Punjab Institute of Cardiology, Lahore. Blood samples of the healthy subjects of comparable age group without any history of cardiac ailment were also collected for the control comparisons. The sera of CMP were separated and used for the study of the protein profiles with sodium dodecyle sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in first dimension. Quantification of various protein fractions done by Gene Genius Bio-imaging Gel Documentation System that provide the data of molecular weights and the percent raw volume covered by each of the fractions. The protein fractions that showed significant variation were separated by using the technique of electro blotting and electro elution and run on isoelectric focusing (IEF) in second dimension to determine their isoelectric points. The most pertinent results in the comparison were the significant increase in apolipoprotein B, Ceruloplasmin, apolipoprotein A-I and transthyretin in the sera of patients of CMP compared to healthy subjects. These results show that level of apolipoprotein B, Ceruloplasmin, apolipoprotein A-I and transthyretin are strong predictor of CMP and can also be used for the diagnosis of CMP. (author)

Tuning size and catalytic activity of nano-clusters of cobalt oxide

Indian Academy of Sciences (India)

Unknown

oxalic acid, (2) co-precipitating cobalt nitrate with sodium carbonate, and (3) using sodium dodecyl sul- .... Co(NO3)2 + Na2CO3 → CoCO3 + 2NaNO3,. CoCO3. ∆. → ∆ CoO + CO2,. CoO → (in air and heating) Co3O4. In method III, cobalt nitrate, sodium dodecyl sul- .... The conversion of cyclohexane on the current po-.

Studies on antigenic cross-reactivity of Trichuris ovis with host mucosal antigens in goat

Directory of Open Access Journals (Sweden)

Gautam Patra

2015-12-01

Full Text Available Objective: To ascertain whether immunodominant antigens of Trichuris ovis might share and cross react with host molecule. Methods: Two crude protein preparations from anterior and posterior parts of Trichuris ovis were characterized along with host mucosal antigen by double immunodiffusion, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting technique. Conventional scanning electron microscopy was performed as per standard procedure. Results: Sharp and distinct bands of three antigens have been found in double immunodiffusion using hyperimmune serum raised in rabbit indicating the presence of specific antibody against each antigen. All three antigens have shown major and minor bands with molecular weight ranging from 15 to 110 kDa during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Conclusions: The antigenic cross-reactivity was thought to result from shared antigens. The existence of paracloacal papillae found in the anterior part of the male was not a unique feature for species differentiation.

Cross-linking proteins by laccase: Effects on the droplet size and rheology of emulsions stabilized by sodium caseinate.

Science.gov (United States)

Sato, A C K; Perrechil, F A; Costa, A A S; Santana, R C; Cunha, R L

2015-09-01

The aim of this work was to evaluate the influence of laccase and ferulic acid on the characteristics of oil-in-water emulsions stabilized by sodium caseinate at different pH (3, 5 and 7). Emulsions were prepared by high pressure homogenization of soybean oil with sodium caseinate solution containing varied concentrations of laccase (0, 1 and 5mg/mL) and ferulic acid (5 and 10mM). Laccase treatment and pH exerted a strong influence on the properties with a consequent effect on stability, structure and rheology of emulsions stabilized by Na-caseinate. At pH7, O/W emulsions were kinetically stable due to the negative protein charge which enabled electrostatic repulsion between oil droplets resulting in an emulsion with small droplet size, low viscosity, pseudoplasticity and viscoelastic properties. The laccase treatment led to emulsions showing shear-thinning behavior as a result of a more structured system. O/W emulsions at pH5 and 3 showed phase separation due to the proximity to protein pI, but the laccase treatment improved their stability of emulsions especially at pH3. At pH3, the addition of ferulic acid and laccase produced emulsions with larger droplet size but with narrower droplet size distribution, increased viscosity, pseudoplasticity and viscoelastic properties (gel-like behavior). Comparing laccase treatments, the combined addition of laccase and ferulic acid generally produced emulsions with lower stability (pH5), larger droplet size (pH3, 5 and 7) and higher pseudoplasticity (pH5 and 7) than emulsion with only ferulic acid. The results suggested that the cross-linking of proteins by laccase and ferulic acid improved protein emulsifying properties by changing functional mechanisms of the protein on emulsion structure and rheology, showing that sodium caseinate can be successfully used in acid products when treated with laccase. Copyright © 2015 Elsevier Ltd. All rights reserved.

Formation of a covalent complex between the terminal protein of pneumococcal bacteriophage Cp-1 and 5'-dAMP

Energy Technology Data Exchange (ETDEWEB)

Garcia, P.; Hermoso, J.M.; Garcia, J.A.; Garcia, E.; Lopez, R.; Salas, M.

1986-04-01

Incubation of extracts of Cp-1-infected Streptococcus pneumoniae with (..cap alpha..-/sup 32/P)dATP produced a labeled protein with the electrophoretic mobility of the Cp-1 terminal protein. The reaction product was resistant to treatment with micrococcal nuclease and sensitive to treatment with proteinase K. Incubation of the /sup 32/P-labeled protein with 5 M piperidine for 4 h at 50/sup 0/C released 5'-dAMP, indicating that a covalent complex between the terminal protein and 5'-dAMP was formed in vitro. When the four deoxynucleoside triphosphates were included in the reaction mixture, a labeled complex of slower electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gels than the terminal protein-dAMP complex was also found, indicating that the Cp-1 terminal protein-dAMP complex can be elongated and, therefore, that it is an initiation complex. Treatment of the /sup 32/P-labeled terminal protein-dAMP complex with 5.8 M HCl at 110/sup 0/C for 2 h yielded phosphothreonine. These results, together with the resistance of the terminal protein-DNA linkage to hydroxylamine, suggest that the Cp-1 terminal protein is covalently linked to the DNA through a phosphoester bond between L-threonine and 5'-dAMP, namely, a O-5'-deoxyadenylyl-L-threonine bond.

Preparation of scaffolds from human hair proteins for tissue-engineering applications

International Nuclear Information System (INIS)

Verma, Vipin; Verma, Poonam; Ray, Alok R; Ray, Pratima

2008-01-01

Human hair proteins were isolated and purified for the fabrication of tissue-engineering scaffolds. Their cellular compatibility was studied using NIH3T3 mice fibroblast cells. The proteins were characterized using FTIR spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis for molecular weights and two-dimensional polyacrylamide gel electrophoresis for their isoelectric points (pIs). The molecular weights of keratins were in the range of 40-60 kilo-Daltons (kDa) and of matrix proteins were in the range of 15-30 kDa. The pIs of keratins were found to be in the range of 4.5-5.3. Sponges of the proteins were formed by lyophilization. Scanning electron microscopy was performed to examine the surface. Swelling studies were carried out in phosphate buffer saline at physiological pH 7.4. The hydrophilic character of the protein surface was studied by determining an average contact angle, which came to be 37 0 . The wells of tissue culture plates were coated with these proteins for studying the attachment and morphology of the cells. The protein detachment study was done to ensure the adsorption of proteins on the wells until the completion of the experiments. The cellular growth on a protein-coated surface showed three-dimensional 'bulged' morphology due to cell-cell and cell-matrix contacts. The sponges of human hair proteins supported more cells for a longer period than control. The morphology and cell proliferation studies exhibited by NIH3T3 cells on these proteins have shown their potential to be used as tissue-engineering scaffolds with better cell-cell contacts and leucine-aspartic acid-valine (LDV)-mediated cell-matrix interactions

Glycogen-bound polyphosphate kinase from the archaebacterium Sulfolobus acidocaldarius.

OpenAIRE

Skórko, R; Osipiuk, J; Stetter, K O

1989-01-01

Glycogen-bound polyphosphate kinase has been isolated from a crude extract of Sulfolobus acidocaldarius by isopycnic centrifugation in CsCl. Divalent cations (Mn2+ greater than Mg2+) stimulated the reaction. The enzyme does not require the presence of histones for its activity; it is inhibited strongly by phosphate and slightly by fluoride. The protein from the glycogen complex migrated in a sodium dodecyl sulfate-polyacrylamide gel as a 57-kilodalton protein band; after isoelectric focusing ...

Isolation and characterization of α-amylase from marine ...

African Journals Online (AJOL)

The α-amylase of marine Pseudomonas sp. K6-28-040 was purified through a series of three steps and the purity of enzymes was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The results showed that, the enzyme was purified 4.7-fold with a specific activity of 134.6 U/mg protein and a yield of 44% ...

Characterization of airag collected in Ulaanbaatar, Mongolia with emphasis on isolated lactic acid bacteria

OpenAIRE

Suk-Ho Choi

2016-01-01

Abstract Background Airag, alcoholic sour-tasting beverage, has been traditionally prepared by Mongolian nomads who naturally ferment fresh mares’ milk. Biochemical and microbiological compositions of airag samples collected in Ulaanbaatar, Mongolia and physiological characteristics of isolated lactic acid bacteria were investigated. Methods Protein composition and biochemical composition were determined using sodium dodecyl sulfate-gel electrophoresis and high performance liquid chromatograp...

Studies on antigenic cross-reactivity of Trichuris ovis with host mucosal antigens in goat

OpenAIRE

Gautam Patra; Seikh Sahanawaz Alam; Sonjoy Kumar Borthakur; Hridayesh Prasad

2015-01-01

Objective: To ascertain whether immunodominant antigens of Trichuris ovis might share and cross react with host molecule. Methods: Two crude protein preparations from anterior and posterior parts of Trichuris ovis were characterized along with host mucosal antigen by double immunodiffusion, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting technique. Conventional scanning electron microscopy was performed as per standard procedure. Results: Sharp...

Association of protein C23 with rapidly labeled nucleolar RNA

International Nuclear Information System (INIS)

Herrera, A.H.; Olson, M.O.

1986-01-01

The association of nucleolar phosphoprotein C23 with preribosomal ribonucleoprotein (RNP) particles was examined in Novikoff hepatoma nucleoli. RNA was labeled with [ 3 H]uridine for various times in cell suspensions, and RNP particles were extracted from isolated nucleoli and fractionated by sucrose gradient ultracentrifugation. The majority of protein C23 cosedimented with fractions containing rapidly labeled RNA (RL fraction). To determine whether there was a direct association of RNA with protein C23, the RL fraction was exposed to ultraviolet (UV) light (254 nm) for short periods of time. After 2 min of exposure there was a 50% decrease in C23 as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses, with no significant further decrease at longer times. When UV-treated fractions were subjected to phenol/chloroform extractions, as much as 30% of the labeled RNA was found in the phenol (protein) layer, indicating that RNA became cross-linked to protein. Similarly, there was an increase in protein C23 extracted into the water layer after irradiation. By SDS-PAGE analyses the cross-linked species migrated more slowly than protein C23, appearing as a smear detected either by [ 3 H]uridine radioactivity or by anti-C23 antibody. With anti-C23 antibodies, up to 25% of the labeled RNA was precipitated from the RL fraction. Dot-blot hybridizations, using cloned rDNA fragments as probes, indicated that the RNA in the RL fraction and the immunoprecipitated RNA contained sequences from 18S and 28S ribosomal RNA

Cloning and characterization of the fatty acid-binding protein gene from the protoscolex of Taenia multiceps.

Science.gov (United States)

Nie, Hua-Ming; Xie, Yue; Fu, Yan; Yang, Ying-Dong; Gu, Xiao-Bin; Wang, Shu-Xian; Peng, Xi; Lai, Wei-Ming; Peng, Xue-Rong; Yang, Guang-You

2013-05-01

Taenia multiceps (Cestoda: Taeniidae), a worldwide cestode parasite, is emerging as an important helminthic zoonosis due to serious or fatal central nervous system disease commonly known as coenurosis in domestic and wild ruminants including humans. Herein, a fatty acid-binding protein (FABP) gene was identified from transcriptomic data in T. multiceps. This gene, which contains a complete coding sequence, was amplified by reverse-transcriptase polymerase chain reaction. The corresponding protein, which was named TmFABP, had a molecular weight of 14 kDa, and subsequently was recombinantly expressed in Escherichia coli. The fusion protein was purified on Ni-NTA beads (Bio-Rad). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analyses showed that the purified recombinant protein caused immunogenicity. Immunohistochemical studies showed that TmFABP was expressed at the tegumental level in the protoscolices and in the cells between the body wall and parenchyma layer of the cestode. In sections from gravid proglottids, intense staining was detected in the uterus and eggs. Based on this, TmFABP could be switched on during differentiation of germinative layers to protoscoleces and from metacestodes to adult worms. Taken together, our results already reported for T. multiceps suggest the possibility of TmFABP developing a vaccine to control and prevent coenurosis.

Relationship between proportion and composition of albumins, and in vitro protein digestibility of raw and cooked pea seeds (Pisum sativum L.).

Science.gov (United States)

Park, Sei Joon; Kim, Tae Wan; Baik, Byung-Kee

2010-08-15

Peas provide an excellent plant protein resource for human diets, but their proteins are less readily digestible than animal proteins. To identify the relationship between composition and in vitro digestibility of pea protein, eight pea varieties with a wide range of protein content (157.3-272.7 g kg(-1)) were determined for the proportion of albumins and globulins, their compositions using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and in vitro protein digestibility (IVPD) before and after heat treatment using a multi-enzyme (trypsin, chymotrypsin and peptidase) method. The proportion of albumins based on total seed protein content decreased from 229 to 147 g kg(-1) as seed protein content increased from 157.3 to 272.7 g kg(-1), while the proportion of globulins increased from 483 to 590 g kg(-1). The IVPDs of eight raw pea seeds were 79.9-83.5%, with significant varietal variations, and those were improved to 85.9-86.8% by cooking. Albumins, including (pea albumins 2) PA2, trypsin inhibitor, lectin and lipoxygenase, were identified as proteolytic resistant proteins. Globulins were mostly digested by protease treatment after heating. The quantitative ratio of albumins and globulins, and the quantitative variations of albumin protein components, including lipoxygenase, PA2, lectins and trypsin inhibitors, appear to influence the protein digestibility of both raw and cooked pea seeds. Copyright (c) 2010 Society of Chemical Industry.

Side-chain dynamics of a detergent-solubilized membrane protein: Measurement of tryptophan and glutamine hydrogen-exchange rates in M13 coat protein by 1H NMR spectroscopy

International Nuclear Information System (INIS)

O'Neil, J.D.J.; Sykes, B.D.

1989-01-01

M13 coat protein is a small (50 amino acids) lipid-soluble protein that becomes an integral membrane protein during the infection stage of the life cycle of the M13 phage and is therefore used as a model membrane protein. To study side-chain dynamics in the protein, the authors have measured individual hydrogen-exchange rates for a primary amide in the side chain of glutamine-15 and for the indole amine of tryptophan-26. The protein was solubilized with the use of perdeuteriated sodium dodecyl sulfate (SDS), and hydrogen-exchange rates were measured by using 1 H nuclear magnetic resonance spectroscopy. The glutamine-15 syn proton exchanged at a rate identical with that in glutamine model peptides except that the pH corresponding to minimum exchange was elevated by about 1.5 pH units. The tryptophan-26 indole amine proton exchange was biphasic, suggesting that two populations of tryptophan-26 exist. It is suggested that the two populations may reflect protein dimerization or aggregation in the SDS micelles. The pH values of minimum exchange for tryptophan-26 in both environments were also elevated by 1.3-1.9 pH units. This phenomenon is reproduced when small tryptophan- and glutamine-containing hydrophobic peptides are dissolved in the presence of SDS micelles. The electrostatic nature of this phenomenon is proven by showing that the minimum pH for exchange can be reduced by dissolving the hydrophobic peptides in the positively charged detergent micelle dodecyltrimethylammonium bromide

Cardiac sodium channel NaV1.5 distribution in myocytes via interacting proteins: the multiple pool model.

Science.gov (United States)

Shy, Diana; Gillet, Ludovic; Abriel, Hugues

2013-04-01

The cardiac sodium current (INa) is responsible for the rapid depolarization of cardiac cells, thus allowing for their contraction. It is also involved in regulating the duration of the cardiac action potential (AP) and propagation of the impulse throughout the myocardium. Cardiac INa is generated by the voltage-gated Na(+) channel, NaV1.5, a 2016-residue protein which forms the pore of the channel. Over the past years, hundreds of mutations in SCN5A, the human gene coding for NaV1.5, have been linked to many cardiac electrical disorders, including the congenital and acquired long QT syndrome, Brugada syndrome, conduction slowing, sick sinus syndrome, atrial fibrillation, and dilated cardiomyopathy. Similar to many membrane proteins, NaV1.5 has been found to be regulated by several interacting proteins. In some cases, these different proteins, which reside in distinct membrane compartments (i.e. lateral membrane vs. intercalated disks), have been shown to interact with the same regulatory domain of NaV1.5, thus suggesting that several pools of NaV1.5 channels may co-exist in cardiac cells. The aim of this review article is to summarize the recent works that demonstrate its interaction with regulatory proteins and illustrate the model that the sodium channel NaV1.5 resides in distinct and different pools in cardiac cells. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction. Copyright © 2012 Elsevier B.V. All rights reserved.

Physicochemical characterization of native and modified sodium caseinate- Vitamin A complexes.

Science.gov (United States)

Gupta, Chitra; Arora, Sumit; Syama, M A; Sharma, Apurva

2018-04-01

Native and modified sodium caseinate- Vitamin A complexes {Sodium caseinate- Vit A complex by stirring (NaCas-VA ST), succinylated sodium caseinate- Vit A complex by stirring (SNaCas-VA ST), reassembled sodium caseinate- Vit A complex (RNaCas-VA) and reassembled succinylated sodium caseinate- Vit A complex (RSNaCas-VA)} were prepared and characterized for their physicochemical characteristics e.g. particle size, zeta potential, turbidity analysis and tryptophan intensities which confirmed structural modification of both native (NaCas-VA ST) and modified (SNaCas-VA ST, RNaCas-VA and RSNaCas- VA) proteins upon complex formation with vitamin A. Binding of vitamin A to milk protein reduced the turbidity caused by vitamin A, however, the particle size and zeta potential of milk protein increased after complexation. Microstructure details of NaCas (spray dried) showed uniform spherical structure, however, other milk proteins and milk protein- Vit A complexes (freeze dried) showed broken glass and flaky structures. Tiny particles were observed on the surface of reassembled protein and reassembled protein- Vit A complexes. Binding of vitamin A to milk protein did not have an influence on the electrophoretic mobility and elution profile (RP-HPLC). Copyright © 2018 Elsevier Ltd. All rights reserved.

Protein profile of Chlamydophila abortus isolates from Kerala, India

Directory of Open Access Journals (Sweden)

Binu K Mani

Full Text Available Chlamydiae are of microbiological interest because of their mode of interaction with eukaryotic host cells and their specialized life cycle with unique features of parasitism. Reports regarding prevalence of infections of Chlamydophila abortus, the causative organism for chlamydial abortions in livestock, was the basis of the study. Two isolates, one each from cattle and goat abortion along with a reference isolate, were used for characterization with Sodium Dodecyl Sulphate-Poly Acrylamide Gel Electrophoresis (SDS-PAGE. Elementary bodies infected Mc Coy cells, harvested from bottle cultures were disrupted by Teflon coated magnetic pellet. Urografin-76 diluted with Tris-Potassium hydrochloride was used for purification of Elementary bodies of Chlamydophila abortus organism. On protein estimation of Elementary bodies by Biuret method, all the three isolates revealed protein concentration between 500-1000 mg/100ml, which were sufficient for electrophoresis. Ten percent of resolving gel and five percent of stacking gel of polyacrylamide in which 10g of processed isolate samples along with standard protein marker and Mc Coy cell protein (control were electrophoresed. Using Alpha Imager Gel Documentation System, the protein bands were analyzed. Twelve bands each for local bovine isolate and reference isolate were noticed while only 10 bands were there in the caprine isolate. Additional bands of 148 kDa and 135 kDa were present in bovine isolate, compared to the reference isolate, while 152 kDa and 137 kDa bands were unique for caprine isolate. [Vet. World 2011; 4(10.000: 470-472

Effect of high-intensity ultrasound on the technofunctional properties and structure of jackfruit (Artocarpus heterophyllus) seed protein isolate.

Science.gov (United States)

Resendiz-Vazquez, J A; Ulloa, J A; Urías-Silvas, J E; Bautista-Rosales, P U; Ramírez-Ramírez, J C; Rosas-Ulloa, P; González-Torres, L

2017-07-01

The influence of high-intensity ultrasound (HIU) on the technofunctional properties and structure of jackfruit seed protein isolate (JSPI) was investigated. Protein solutions (10%, w/v) were sonicated for 15min at 20kHz to the following levels of power output: 200, 400, and 600W (pulse duration: on-time, 5s; off-time 1s). Compared with untreated JSPI, HIU at 200W and 400W improved the oil holding capacity (OHC) and emulsifying capacity (EC), but the emulsifying activity (EA) and emulsion stability (ES) increased at 400W and 600W. The foaming capacity (FC) increased after all HIU treatments, as opposed to the water holding capacity (WHC), least gelation concentration (LGC), and foaming stability (FS), which all decreased except at pH 4 for FS. Tricine sodium dodecyl sulfate polyacrylamide gel electrophoresis (Tricine-SDS-PAGE) showed changes in the molecular weight of protein fractions after HIU treatment. Scanning electron microscopy (SEM) demonstrated that HIU disrupted the microstructure of JSPI, exhibiting larger aggregates. Surface hydrophobicity and protein solubility of the JSPI dispersions were enhanced after ultrasonication, which increased the destruction of internal hydrophobic interactions of protein molecules and accelerated the molecular motion of proteins to cause protein aggregation. These changes in the technofunctional and structural properties of JSPI could meet the complex needs of manufactured food products. Copyright © 2017 Elsevier B.V. All rights reserved.

A proteomic style approach to characterize a grass mix product reveals potential immunotherapeutic benefit.

Science.gov (United States)

Bullimore, Alan; Swan, Nicola; Alawode, Wemimo; Skinner, Murray

2011-09-01

Grass allergy immunotherapies often consist of a mix of different grass extracts, each containing several proteins of different physiochemical properties; however, the subtle contributions of each protein are difficult to elucidate. This study aimed to identify and characterize the group 1 and 5 allergens in a 13 grass extract and to standardize the extraction method. The grass pollens were extracted in isolation and pooled and also in combination and analyzed using a variety of techniques including enzyme-linked immunosorbent assay, liquid chromatog-raphy-mass spectrometry, and sodium dodecyl sulfate-polyacrylam-ide gel electrophoresis. Gold-staining and IgE immunoblotting revealed a high degree of homology of protein bands between the 13 species and the presence of a densely stained doublet at 25-35 kD along with protein bands at approximately 12.5, 17, and 50 kD. The doublet from each grass species demonstrated a high level of group 1 and 5 interspecies homology. However, there were a number of bands unique to specific grasses consistent with evolutionary change and indicative that a grass mix immunotherapeutic could be considered broad spectrum. Sodium dodecyl sulfate-polyacrylamide gel electro-phoresis and IgE immunoblotting showed all 13 grasses share a high degree of homology, particularly in terms of group 1 and 5 allergens. IgE and IgG enzyme-linked immunosorbent assay potencies were shown to be independent of extraction method.

Isolation and characterization of an RIP (ribosome-inactivating protein)-like protein from tobacco with dual enzymatic activity.

Science.gov (United States)

Sharma, Neelam; Park, Sang-Wook; Vepachedu, Ramarao; Barbieri, Luigi; Ciani, Marialibera; Stirpe, Fiorenzo; Savary, Brett J; Vivanco, Jorge M

2004-01-01

Ribosome-inactivating proteins (RIPs) are N-glycosidases that remove a specific adenine from the sarcin/ricin loop of the large rRNA, thus arresting protein synthesis at the translocation step. In the present study, a protein termed tobacco RIP (TRIP) was isolated from tobacco (Nicotiana tabacum) leaves and purified using ion exchange and gel filtration chromatography in combination with yeast ribosome depurination assays. TRIP has a molecular mass of 26 kD as evidenced by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and showed strong N-glycosidase activity as manifested by the depurination of yeast rRNA. Purified TRIP showed immunoreactivity with antibodies of RIPs from Mirabilis expansa. TRIP released fewer amounts of adenine residues from ribosomal (Artemia sp. and rat ribosomes) and non-ribosomal substrates (herring sperm DNA, rRNA, and tRNA) compared with other RIPs. TRIP inhibited translation in wheat (Triticum aestivum) germ more efficiently than in rabbit reticulocytes, showing an IC50 at 30 ng in the former system. Antimicrobial assays using highly purified TRIP (50 microg mL(-1)) conducted against various fungi and bacterial pathogens showed the strongest inhibitory activity against Trichoderma reesei and Pseudomonas solancearum. A 15-amino acid internal polypeptide sequence of TRIP was identical with the internal sequences of the iron-superoxide dismutase (Fe-SOD) from wild tobacco (Nicotiana plumbaginifolia), Arabidopsis, and potato (Solanum tuberosum). Purified TRIP showed SOD activity, and Escherichia coli Fe-SOD was observed to have RIP activity too. Thus, TRIP may be considered a dual activity enzyme showing RIP-like activity and Fe-SOD characteristics.

The human receptor for urokinase plasminogen activator. NH2-terminal amino acid sequence and glycosylation variants

DEFF Research Database (Denmark)

Behrendt, N; Rønne, E; Ploug, M

1990-01-01

-PA. The purified protein shows a single 55-60 kDa band after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining. It is a heavily glycosylated protein, the deglycosylated polypeptide chain comprising only 35 kDa. The glycosylated protein contains N-acetyl-D-glucosamine and sialic acid......, but no N-acetyl-D-galactosamine. Glycosylation is responsible for substantial heterogeneity in the receptor on phorbol ester-stimulated U937 cells, and also for molecular weight variations among various cell lines. The amino acid composition and the NH2-terminal amino acid sequence are reported...

Signal amplification in electrochemical detection of buckwheat allergenic protein using field effect transistor biosensor by introduction of anionic surfactant

Directory of Open Access Journals (Sweden)

Sho Hideshima

2016-03-01

Full Text Available Food allergens, especially buckwheat proteins, sometimes induce anaphylactic shock in patients after ingestion. Development of a simple and rapid screening method based on a field effect transistor (FET biosensor for food allergens in food facilities or products is in demand. In this study, we achieved the FET detection of a buckwheat allergenic protein (BWp16, which is not charged enough to be electrically detected by FET biosensors, by introducing additional negative charges from anionic surfactants to the target proteins. A change in the FET characteristics reflecting surface potential caused by the adsorption of target charged proteins was observed when the target sample was coupled with the anionic surfactant (sodium dodecyl sulfate; SDS, while no significant response was detected without any surfactant treatment. It was suggested that the surfactant conjugated with the protein could be useful for the charge amplification of the target proteins. The surface plasmon resonance analysis revealed that the SDS-coupled proteins were successfully captured by the receptors immobilized on the sensing surface. Additionally, we obtained the FET responses at various concentrations of BWp16 ranging from 1 ng/mL to 10 μg/mL. These results suggest that a signal amplification method for FET biosensing is useful for allergen detection in the food industry. Keywords: Field effect transistor biosensor, Food allergen, Signal amplification, Ionic surfactant, Intrinsic charge

Dog rose (Rosa canina L.) as a functional ingredient in porcine frankfurters without added sodium ascorbate and sodium nitrite.

Science.gov (United States)

Vossen, Els; Utrera, Mariana; De Smet, Stefaan; Morcuende, David; Estévez, Mario

2012-12-01

The effect of dog rose (Rosa canina L.; RC), rich in polyphenols and ascorbic acid, on lipid and protein oxidation, colour stability and texture of frankfurters was investigated. Four treatments were prepared: with 5 or 30 g/kg RC extract and without sodium ascorbate and sodium nitrite (5RC and 30RC, respectively), a positive control (with sodium ascorbate and sodium nitrite; PC) and a negative control (without sodium ascorbate, sodium nitrite or RC extract; NC). Hexanal values were much higher throughout storage in NC compared to RC and PC frankfurters (Prose can act as a natural antioxidant in frankfurters, but not as full replacer for sodium nitrite. Copyright © 2012 Elsevier Ltd. All rights reserved.

Isolation and Identification of Outer Membrane Proteins of Helicobacter Pylori of Iranian Patient by SDS-PAGE

Directory of Open Access Journals (Sweden)

M. Doosty

1998-04-01

Full Text Available The function of Helicobacter pylori (H.pylori is confirmed as one of the factors which motivates gastric and duodenal ulcer and gastritis. Various methods are used to diagnose the infection. Serological tests are the easiest and most harmless for the patients. Probably, H.pylori strains in Iran are different from the strains in other countries. Hence, it seems neccessary to design a specific serological test to recognize and identify different strains of bacterial antigenic proteins of Iranian patients."nSince the most manifest and specific to these bacterial antigens are the "Outer Membrane Protein" (OMP, therefore, the first necessary step is to separate and purify H.pylori OMP and then to identify antigenic proteins."nIn this study, we received bacteria colony that belonged to 15 patients with gastric or duodenal ulcer, which had been growed in blood agar or brucella broth. After processing such as washing, freezing and defreezing, sonicating, centrifugation with high speed (10,000 g and treatment with sarcosyl, the sarcosyl insoluble fraction was extracted. Sodium Dodecyl Sulfate - Poly Acrylamide Gel Electrophoresis (SDS-PAGE was preformed. From all 15 OMP specimens, we isolated protein bands."nThe first two bands with higher MW, were major bands and the two lighter bands were the minor bands. Approximate MW of these 4 proteins are equal to 67000, 61000, 30000 and 17000 dalton

Synthesis of potassium sodium niobate nanostructures by hydrothermal combining with the sol-gel method

Energy Technology Data Exchange (ETDEWEB)

Meng, Xianghe; Wang, Wen, E-mail: wangwen@hit.edu.cn; Ke, Hua; Rao, Jiancun; Zhou, Yu

2016-10-15

Graphical abstract: We prepared novel metastable perovskite K{sub 0.52}Na{sub 0.48}NbO{sub 3} microstructures with a morphotropic phase boundary (MPB) between rhombohedral and tetragonal via hydrothermal method with SDS surfactant-assist. - Highlights: • KNbO{sub 3}-type orthorhombic K{sub 1−x}Na{sub x}NbO{sub 3} nanowires were prepared by hydrothermal method. • Metastable K{sub 0.52}Na{sub 0.48}NbO{sub 3} microfingers have a morphotropic phase boundary. • Sodium dodecyl sulfate could improve the crystallinity of K{sub 0.52}Na{sub 0.48}NbO{sub 3} powders. • The Curie temperature of rhombohedral-tetragonal KNN was 555 °C. - Abstract: In this paper the K{sub 1−x}Na{sub x}NbO{sub 3}(KNN) nanostructures were synthesized by hydrothermal method using KNN gel powders as precursors. KNbO{sub 3}-type orthorhombic KNN nanowires and perovskite KNN microfingers with a morphotropic phase boundary (MPB) between rhombohedral and tetragonal characterized by X-ray diffraction and Raman spectroscopy were obtained at 190 °C and 220 °C, respectively. KNbO{sub 3}-type orthorhombic KNN nanowires had rectangular shape and the growth direction of these nanowires was [0 0 1]. The rhombohedral-tetragonal KNN microfingers were metastable, and changed the rhombohedral-tetragonal phase into the orthorhombic phase via thermal treatment at 600 °C then cooled down to room temperature. Sodium dodecyl sulfate (SDS) as surfactant was added to the hydrothermal reaction. It was found that SDS could improve the crystallinity of the rhombohedral-tetragonal K{sub 0.52}Na{sub 0.48}NbO{sub 3} and reduce the impurity effectively. The tetragonal-cubic phase transition temperature (Tc) of the rhombohedral-tetragonal powders appeared at 555 °C.

[Studies of progestin specific binding protein in the human prostate. [III]; Sodium molybdate effect on SDG analysis].

Science.gov (United States)

Imai, K; Kumasaka, F; Kobayashi, M; Takahashi, Y; Takahashi, E; Yamanaka, H

1985-08-20

The effect of sodium molybdate on the specific binding protein (SBP) of synthetic progestin 17 alpha-methyl-[3H]-promegestone (R5020) in the cytosol of the human prostate was studied. In a sucrose density gradient analysis, two R5020 SBP components at 4S and 7-8S were observed. It was apparent that the 4S component was reduced and the 7-8S component increased with the addition of 10mM sodium molybdate into the cytosol. Therefore, the molybdate enhancement degree on total SBP amount (4S plus 7-8S) was decided by the relationship between the decreasing rate at 4S and the increasing one at 7-8S. It was shown that the molybdate effect was time-dependent and was not related to the SBP state, whether it was bounded with steroid or not. Moreover, it was estimated that the molybdate effect was not related to phosphatase inhibition since R5020 SBP in SDG was not enhanced by the addition of sodium fluoride which was a phosphatase inhibitor. In this report, the possibility of the existence of the 7-8S forming factor in the human prostate and the relationship between it and sodium molybdate was also discussed through an experiment on a Sephadex G-25.

Radiation-induced structural changes in membrane proteins of human erythrocytes and ghosts and the relation to cellular morphology

Energy Technology Data Exchange (ETDEWEB)

Schuurhuis, G.J.; Hommes, J.; Vos, J.; Molenaar, I.; Konings, A.W.T. (Rijksuniversiteit Groningen (Netherlands))

1984-02-01

Isolated human erythrocytes and ghosts were irradiated with X-rays under different experimental conditions and the effect examined with regard to the structure of membrane proteins and morphology of whole cells and ghosts. From sodium dodecyl sulphate/polyacrylamide gel electrophoresis it is concluded that spectrin (band 1 and 2) is the most radiosensitive of the membrane proteins examined. X-irradiation of cells and ghosts induced covalent cross-linking of a small fraction of membrane proteins. In the protein aggregates thus formed spectrin was found to be the major component. Molecular disulphide (-SS-) bridges seemed to account for part of the cross-links observed. Some nondisulphide cross-links were found, especially when ghosts were irradiated. Significant amounts of spectrin aggregates were formed during post-irradiation incubation at 37/sup 0/C but not at 4/sup 0/C. In the intact cell a transformation in shape from discocyte to echinocyte accompanied the process of post-irradiation spectrin aggregation. The characteristics of both processes, such as their reversibility with adenosine, point to a metabolic involvement. It is shown that there is no causal relationship between the two phenomena observed. Possible causes of the post-irradiation effects and the parallelism with similar processes in non-irradiated metabolically depleted cells are discussed.

Radiation-induced structural changes in membrane proteins of human erythrocytes and ghosts and the relation to cellular morphology

International Nuclear Information System (INIS)

Schuurhuis, G.J.; Hommes, J.; Vos, J.; Molenaar, I.; Konings, A.W.T.

1984-01-01

Isolated human erythrocytes and ghosts were irradiated with X-rays under different experimental conditions and the effect examined with regard to the structure of membrane proteins and morphology of whole cells and ghosts. From sodium dodecyl sulphate/polyacrylamide gel electrophoresis it is concluded that spectrin (band 1 and 2) is the most radiosensitive of the membrane proteins examined. X-irradiation of cells and ghosts induced covalent cross-linking of a small fraction of membrane proteins. In the protein aggregates thus formed spectrin was found to be the major component. Molecular disulphide (-SS-) bridges seemed to account for part of the cross-links observed. Some nondisulphide cross-links were found, especially when ghosts were irradiated. Significant amounts of spectrin aggregates were formed during post-irradiation incubation at 37 0 C but not at 4 0 C. In the intact cell a transformation in shape from discocyte to echinocyte accompanied the process of post-irradiation spectrin aggregation. The characteristics of both processes, such as their reversibility with adenosine, point to a metabolic involvement. It is shown that there is no causal relationship between the two phenomena observed. Possible causes of the post-irradiation effects and the parallelism with similar processes in non-irradiated metabolically depleted cells are discussed. (author)

Investigation of total seed storage proteins of pakistani and japanese maize (zea mays l.) through sds-page markers

International Nuclear Information System (INIS)

Shinwari, Z.K.

2014-01-01

The assessment of genetic diversity among the members of a species is of vital importance for successful breeding and adaptability. In the present study 83 genotypes of maize of Pakistani and Japanese origin were evaluated for the total seed storage proteins using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) through vertical slab unit. The total protein subunits were separated on 12% polyacrylamide gel using standard protocols. A total of 18 protein subunits were noted out of which 7 (39%) were monomorphic and 11 (61%) were polymorphic, with molecular weight ranging from 10 to 122 kDa. Coefficients of similarity among the accessions ranged between 0.89 and 1.00. The dendrogram obtained through UPGMA clustering method showed two main clusters: 1 and 2. First cluster comprised of 9 genotypes including Sahiwal-2002, while second cluster contained 74 genotypes including Aaiti-2002 and Sadaf. Over all a low level of polymorphism was observed in total seed storage protein patterns of maize genotypes from Pakistan as well as Japan. It is inferred from the present study that more genotypes of maize could be brought under study and more advanced biochemical techniques with more reliable results could be followed to bring assessment of genetic diversity of maize for planning breeding programs. (author)

Convergent evolution of plant and animal embryo defences by hyperstable non-digestible storage proteins.

Science.gov (United States)

Pasquevich, María Yanina; Dreon, Marcos Sebastián; Qiu, Jian-Wen; Mu, Huawei; Heras, Horacio

2017-11-20

Plants have evolved sophisticated embryo defences by kinetically-stable non-digestible storage proteins that lower the nutritional value of seeds, a strategy that have not been reported in animals. To further understand antinutritive defences in animals, we analysed PmPV1, massively accumulated in the eggs of the gastropod Pomacea maculata, focusing on how its structure and structural stability features affected its capacity to withstand passage through predator guts. The native protein withstands >50 min boiling and resists the denaturing detergent sodium dodecyl sulphate (SDS), indicating an unusually high structural stability (i.e., kinetic stability). PmPV1 is highly resistant to in vitro proteinase digestion and displays structural stability between pH 2.0-12.0 and 25-85 °C. Furthermore, PmPV1 withstands in vitro and mice digestion and is recovered unchanged in faeces, supporting an antinutritive defensive function. Subunit sequence similarities suggest a common origin and tolerance to mutations. This is the first known animal genus that, like plant seeds, lowers the nutritional value of eggs by kinetically-stable non-digestible storage proteins that survive the gut of predators unaffected. The selective pressure of the harsh gastrointestinal environment would have favoured their appearance, extending by convergent evolution the presence of plant-like hyperstable antinutritive proteins to unattended reproductive stages in animals.

Cell envelope proteins of environmental Vibrio cholerae non O1 isolates from Albufera Lake (Valencia, Spain) influence of some factors on OMP expression.

Science.gov (United States)

Amaro, C; Herrero, E; Arnau, A; Garay, E

1989-11-01

The cell envelope proteins of 89 environmental Vibrio cholerae non O1 strains isolated from lake and coastal waters near Valencia, Spain, and six Vibrio cholerae strains from culture collections were analyzed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Considerable heterogeneity was found in the major proteins of the environmental non-O1 strains, but bands between 25,000 and 48,000 daltons were observed in the majority of the strains. Estimated relative mobilities of the total protein profile ranged between 11 and more than 100 Kd. Cluster analysis revealed four groups of strains distinguishable by presence or absence of high and low molecular weight proteins. After treatment with Sarkosyl, the outer membrane proteins (OMPs) were characterized in all strains by densitometric methods. They ranged from 19 to 87 Kilodaltons, and corresponded to the major proteins observed in the total membrane preparations. The major OMP most frequently found had a molecular weight around 37 Kd, similar to that of porins in other Gram-negative bacteria. The OMP composition varied in response to culture medium and growth phase. Generally the OMP expression was affected only in a quantitative way by the growth phase while the growth medium had both a qualitative and a quantitative effect.

Biotechnological production of inducible defense-related proteins in edible radish (raphanus sativus) found in Nepal.

Science.gov (United States)

Khanal, Praval; Karmacharya, Anil; Sharma, Shishir; Nepal, Ashwini K; Shrestha, Kanti

2014-01-01

Fungal infection in plant leads to use of many hazardous antifungal chemicals. Alternative to these chemicals, defense related antifungal proteins can be used in case of fungal diseases. An experiment was done in two varieties of edible radish (Raphanus sativus var. Pyuthane Raato and Raphanus sativus var. all season) with aims to produce defense protein within the plant, to identify and perform molecular characterization of those antifungal proteins. The next aim was to compare the antifungal property of those proteins with commercially available synthetic pesticides. Both varieties of radish were infected with fungi (Alternaria alternata and Fusarium oxysporum). Protein samples were isolated from leaves following the standard protocol as described for β-glucuronidase (GUS) assay and were run along with the standard protein marker of 10-250kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to identify and molecularly characterize them. An additional band in the range of 37-50kDa was observed in the fungal infected samples, which was not seen on uninfected samples. The antifungal assay was carried out for every sample in 96 wells microtitre plate. The extracted protein samples from fungal inoculated plants showed the significant inhibition of fungal growth compared to other samples. On the basis of molecular weight and their antifungal properties, the protein samples from the fungal infected plant were found to be PR2 (Glucanase) and PR3 (Chitinase). Defense related proteins were successfully produced in two varieties of radish found in Nepal. The use of such biologically produced proteins may reduce the use of biologically harmful synthetic pesticides.

A Chip-Capillary Hybrid Device for Automated Transfer of Sample Pre-Separated by Capillary Isoelectric Focusing to Parallel Capillary Gel Electrophoresis for Two-Dimensional Protein Separation

Science.gov (United States)

Lu, Joann J.; Wang, Shili; Li, Guanbin; Wang, Wei; Pu, Qiaosheng; Liu, Shaorong

2012-01-01

In this report, we introduce a chip-capillary hybrid device to integrate capillary isoelectric focusing (CIEF) with parallel capillary sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE) or capillary gel electrophoresis (CGE) toward automating two-dimensional (2D) protein separations. The hybrid device consists of three chips that are butted together. The middle chip can be moved between two positions to re-route the fluidic paths, which enables the performance of CIEF and injection of proteins partially resolved by CIEF to CGE capillaries for parallel CGE separations in a continuous and automated fashion. Capillaries are attached to the other two chips to facilitate CIEF and CGE separations and to extend the effective lengths of CGE columns. Specifically, we illustrate the working principle of the hybrid device, develop protocols for producing and preparing the hybrid device, and demonstrate the feasibility of using this hybrid device for automated injection of CIEF-separated sample to parallel CGE for 2D protein separations. Potentials and problems associated with the hybrid device are also discussed. PMID:22830584

Examination on the protein profiles of salivary glands of P. berghei infected anopheles Sp. post gamma irradiation using SDS-PAGE technique for developing malaria vaccine

International Nuclear Information System (INIS)

Tetriana, D.; Syaifudin, M.

2014-01-01

Sporozoite is a step of malaria parasitic live cycle that is most invasive and appropriate vaccine candidate. Result of experiments showed that malaria vaccine created by attenuating Plasmodium sp sporozoites with gamma rays was proven more effective. Study on the effects of irradiation to the profiles of protein in vaccine development is also important. The aim of this research was to examine the protein profile of salivary glands in sporozoite infected Anopheles sp post gamma irradiation using Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) technique. Examination covered the infection of Anopheles sp with Plasmodium sp, maintenance of infected mosquitoes for 14-16 days to obtain sporozoites, in vivo - in vitro irradiation of mosquitoes, preparation of salivary glands, electrophoresis on 10% SDS-PAGE, and Commassie blue staining. Results showed a different protein profile of infected and non infected salivary glands of Anopheles sp. There was additional protein band numbers at higher dose of irradiation (200 Gy) from sporozoite protein of P. berghei (MW 62 kDa). However, no difference of the profiles of circumsporozoite protein (CSP) observed among gamma irradiation doses of 150, 175 and 200 Gy. These results provide basic information that would lead to further study on the role of sporozoite proteins in malaria vaccine development. (author)

Interspecific variation of total seed protein in wild rice germplasm using SDS-Page

International Nuclear Information System (INIS)

Shah, S.M.A.; Hidayat-ur-Rahman; Abbasi, F.M.; Ashiq, M.; Rabbani, A.M.; Khan, I.A.; Shinwari, Z.K.; Shah, Z.

2011-01-01

Variation in seed protein of 14 wild rice species (Oryza spp.) along with cultivated rice species (O. sativa) was studied using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to assess genetic diversity in the rice germplasm. SDS bands were scored as present (1) or absent (0) for protein sample of each genotype. On the basis of cluster analysis, four clusters were identified at a similarity level of 0.85. O. nivara, O. rufipogon and O. sativa with AA genomes constituted the first cluster. The second cluster comprised O. punctata of BB genome and wild rice species of CC genome i.e., O. rhizomatis and O. officinalis. However, it also contained O. barthii and O. glumaepatula of AA genome. O. australiensis with EE genome, and O. latifolia, O. alta and O. grandiglumis having CCDD genomes comprised the third cluster. The fourth cluster consisted of wild rice species, O. brachyantha with EE genome along with two other wild rice species, O. longistaminata and O. meridionalis of AA genome. Overall, on the basis of total seed protein, the grouping pattern of rice genotypes was mostly compatible with their genome status. The results of the present work depicted considerable interspecific genetic variation in the investigated germplasm for total seed protein. Moreover, the results obtained in this study also suggest that analysis of seed protein can also provide a better understanding of genetic affinity of the germplasm. (author)

Efficiency of serum protein removal from skim milk with ceramic and polymeric membranes at 50 degrees C.

Science.gov (United States)

Zulewska, J; Newbold, M; Barbano, D M

2009-04-01

Raw milk (2,710 kg) was separated at 4 degrees C, the skim milk was pasteurized (72 degrees C, 16 s), split into 3 batches, and microfiltered using pilot-scale ceramic uniform transmembrane pressure (UTP; Membralox model EP1940GL0.1microA, 0.1 microm alumina, Pall Corp., East Hills, NY), ceramic graded permeability (GP; Membralox model EP1940GL0.1microAGP1020, 0.1 microm alumina, Pall Corp.), and polymeric spiral-wound (SW; model FG7838-OS0x-S, 0.3 microm polyvinylidene fluoride, Parker-Hannifin, Process Advanced Filtration Division, Tell City, IN) membranes. There were differences in flux among ceramic UTP, ceramic GP, and polymeric SW microfiltration membranes (54.08, 71.79, and 16.21 kg/m2 per hour, respectively) when processing skim milk at 50 degrees C in a continuous bleed-and-feed 3x process. These differences in flux among the membranes would influence the amount of membrane surface area required to process a given volume of milk in a given time. Further work is needed to determine if these differences in flux are maintained over longer processing times. The true protein contents of the microfiltration permeates from UTP and GP membranes were higher than from SW membranes (0.57, 0.56, and 0.38%, respectively). Sodium-dodecyl-sulfate-PAGE gels for permeates revealed a higher casein proportion in GP and SW permeate than in UTP permeate, with the highest passage of casein through the GP membrane under the operational conditions used in this study. The slight cloudiness of the permeates produced using the GP and SW systems may have been due to the presence of a small amount of casein, which may present an obstacle in their use in applications when clarity is an important functional characteristic. More beta-lactoglobulin passed through the ceramic membranes than through the polymeric membrane. The efficiency of removal of serum proteins in a continuous bleed-and-feed 3x process at 50 degrees C was 64.40% for UTP, 61.04% for GP, and 38.62% for SW microfiltration

Alteration of sodium, potassium-adenosine triphosphatase activity in rabbit ciliary processes by cyclic adenosine monophosphate-dependent protein kinase

International Nuclear Information System (INIS)

Delamere, N.A.; Socci, R.R.; King, K.L.

1990-01-01

The response of sodium, potassium-adenosine triphosphatase (Na,K-ATPase) to cyclic adenosine monophosphate (cAMP)-dependent protein kinase was examined in membranes obtained from rabbit iris-ciliary body. In the presence of the protein kinase together with 10(-5) M cAMP, Na,K-ATPase activity was reduced. No change in Na,K-ATPase activity was detected in response to the protein kinase without added cAMP. Likewise cAMP alone did not alter Na,K-ATPase activity. Reduction of Na,K-ATPase activity was also observed in the presence of the cAMP-dependent protein kinase catalytic subunit. The response of the enzyme to the kinase catalytic subunit was also examined in membranes obtained from rabbit ciliary processes. In the presence of 8 micrograms/ml of the catalytic subunit, ciliary process Na,K-ATPase activity was reduced by more than 50%. To examine whether other ATPases were suppressed by the protein kinase, calcium-stimulated ATPase activity was examined; its activity was stimulated by the catalytic subunit. To test whether the response of the ciliary process Na,K-ATPase is unique, experiments were also performed using membrane preparations from rabbit lens epithelium or rabbit kidney; the catalytic subunit significantly reduced the activity of Na,K-ATPase from the kidney but not the lens. These Na,K-ATPase studies suggest that in the iris-ciliary body, cAMP may alter sodium pump activity. In parallel 86Rb uptake studies, we observed that ouabain-inhibitable potassium uptake by intact pieces of iris-ciliary body was reduced by exogenous dibutryl cAMP or by forskolin

Synthesis of dodecyl lauroyl benzene sulfonate and its application in enhanced oil recovery

Energy Technology Data Exchange (ETDEWEB)

Cui, Zhenggang; Wu, Le; Sun, Mingming; Jiang, Jian-zhong; Wang, Feng [Jiangnan Univ., Wuxi (China). School of Chemical and Material Engineering

2011-09-15

A new hydrophobic surfactant, dodecyl lauroyl benzene sulfonate (DLBS), was synthesized and its application in enhanced oil recovery by alkali-surfactant-polymer (ASP) flooding was studied. The results show that DLBS can be synthesized by reaction of industrial dodecyl benzene with lauroyl chloride in the presence of AlCl{sub 3}, followed by sulfonation with ClSO{sub 3}H and neutralization with NaOH. The lauroyl-group is confirmed to be connected to the para-position of the alkylbenzene by1HNMR spectrum. The synthesized DLBS is well soluble in pure water and reservoir (connate) water at 45 C. It is highly surface active which is indicated by its low CMC of 1.1 . 10{sup -5} mol/L, and its low surface tension, {gamma}{sub cmc} of 28.6 mN m{sup -1}. By mixing with heavy alkylbenzene sulfonates of relatively low average molar mass (387g mol{sup -1}) at a total surfactant concentration of 5 mM, DLBS can reduce the interfacial tension of Daqing crude oil/connate water to an order of 10{sup -3} mN/m at 45 C in the presence of 0.5-1.0 wt.% NaOH and 1000 mg L{sup -1} of polymer. If the NaOH was replaced by a gentle alkaline salt, Na{sub 2}CO{sub 3}, certain amounts of dodecyl dimethyl carboxy betaine were added and the concentration of Na{sub 2}CO{sub 3} was increased to 1.2-2.0 wt.%, the interfacial tension of Daqing crude oil/connate water can also be reduced to an ultralow value. Therefore DLBS is a good hydrophobic surfactant applicable in ASP flooding with either NaOH or Na{sub 2}CO{sub 3} as alkaline agents. (orig.)

ANALISIS PROFIL PROTEIN DARAH ANAK KAMBING PERANAKAN ETAWAH DENGAN PEMBERIAN PAKAN SUBSTITUSI SUSU SAPI

Directory of Open Access Journals (Sweden)

Teguh Wicaksono

2017-08-01

Full Text Available The objective of this study is to determine the protein profile of pre-weaning kids fed with cow's milk as a substitute for dam’s milk. The materials used were 18 Etawah Descendant (PE kids born the twin at the age of 5-13 days from 3-4-year-old dams. This experimental design was a completely randomized design with three treatments with six replications per treatment, namely the control (T0 fed 100% goat’s milk, treatment 1 (T1 fed 50% goat’s milk and 50% cow’s milk, treatment 2 (T2 fed 100% cow’s milk. The protein profile serum was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE method, 12,5% of the resolving gel and 3% of the stacking gel were used. The protein profile of the 5-14 days old PE kids were 19 protein bands with the molecular weight ranging from 15-160 kDa. The kids fed with 100% goat milk (T0 and those substituted by 50% cow's milk (T1, it was produced 19 protein bands with molecular weights ranging from 15 kDa to 155 kDa, while those fed with 100 % cow's milk (T2, it was produced 17 protein bands with molecular weights ranging from 13 kDa to 160 kDa. It can be concluded that the dam's milk substitute using cow's milk at the 50% level does not affect the blood protein profile of goat kids, while the 100% substitute produces the different number and types of protein

Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate-coated nano-magnets for selective adsorption and enrichment of illegal cationic dyes in food matrices prior to high-performance liquid chromatography-diode array detection detection.

Science.gov (United States)

Qi, Ping; Liang, Zhi-An; Wang, Yu; Xiao, Jian; Liu, Jia; Zhou, Qing-Qiong; Zheng, Chun-Hao; Luo, Li-Ni; Lin, Zi-Hao; Zhu, Fang; Zhang, Xue-Wu

2016-03-11

In this study, mixed hemimicelles solid-phase extraction (MHSPE) based on sodium dodecyl sulfate (SDS) coated nano-magnets Fe3O4 was investigated as a novel method for the extraction and separation of four banned cationic dyes, Auramine O, Rhodamine B, Basic orange 21 and Basic orange 22, in condiments prior to HPLC detection. The main factors affecting the extraction of analysts, such as pH, surfactant and adsorbent concentrations and zeta potential were studied and optimized. Under optimized conditions, the proposed method was successful applied for the analysis of banned cationic dyes in food samples such as chili sauce, soybean paste and tomato sauce. Validation data showed the good recoveries in the range of 70.1-104.5%, with relative standard deviations less than 15%. The method limits of determination/quantification were in the range of 0.2-0.9 and 0.7-3μgkg(-1), respectively. The selective adsorption and enrichment of cationic dyes were achieved by the synergistic effects of hydrophobic interactions and electrostatic attraction between mixed hemimicelles and the cationic dyes, which also resulted in the removal of natural pigments interferences from sample extracts. When applied to real samples, RB was detected in several positive samples (chili powders) within the range from 0.042 to 0.177mgkg(-1). These results indicate that magnetic MHSPE is an efficient and selective sample preparation technique for the extraction of banned cationic dyes in a complex matrix. Copyright © 2016 Elsevier B.V. All rights reserved.

Immobilization of myoglobin in sodium alginate composite membranes

Directory of Open Access Journals (Sweden)

Katia Cecília de Souza Figueiredo

2015-06-01

Full Text Available AbstractThe immobilization of myoglobin in sodium alginate films was investigated with the aim of evaluating the protein stability in an ionic polymeric matrix. Myoglobin was chosen due to the resemblance to each hemoglobin tetramer. Sodium alginate, being a natural polysaccharide, was selected as the polymeric matrix because of its chemical structure and film-forming ability. To improve the mechanical resistance of sodium alginate films, the polymer was deposited over the surface of a cellulose acetate support by means of ultrafiltration. The ionic crosslink of sodium alginate was investigated by calcium ions. Composite membrane characterization comprised water swelling tests, water flux, SEM images and UV-visible spectroscopy. The electrostatic interaction between the protein and the polysaccharide did not damage the UV-visible pattern of native myoglobin. A good affinity between sodium alginate and cellulose acetate was observed. The top layer of the dense composite membrane successfully immobilized Myoglobin, retaining the native UV-visible pattern for two months.

Enhanced Hydrophilicity and Protein Adsorption of Titanium Surface by Sodium Bicarbonate Solution

Directory of Open Access Journals (Sweden)

Shengnan Jia

2015-01-01

Full Text Available The aim of this study was to investigate a novel and convenient method of chemical treatment to modify the hydrophilicity of titanium surfaces. Sand-blasted and acid-etched (SLA titanium surfaces and machined titanium surfaces were treated with sodium bicarbonate (NaHCO3 solution. The wetting behavior of both kinds of surfaces was measured by water contact angle (WCA test. The surface microstructure was assessed with scanning electron microscopy (SEM and three-dimensional (3D optical microscopy. The elemental compositions of the surfaces were analyzed by X-ray photoelectron spectroscopy (XPS. The protein adsorption analysis was performed with fibronectin. Results showed that, after 1 M NaHCO3 treatment, the hydrophilicity of both SLA and machined surfaces was enhanced. No significant microstructural change presented on titanium surfaces after NaHCO3 treatment. The deprotonation and ion exchange activities might cause the enhanced hydrophilicity of titanium surfaces. The increased protein adsorption of NaHCO3-treated SLA surfaces might indicate their improved tissue-integration in clinical use.

Contribution of sodium dodecyl sulphate and sodium lauric acid in ...

Indian Academy of Sciences (India)

Tao Q, He H P, Frost R L, Yuan P and Zhu J X 2009 Appl. Surf. Sci. 255 4334. 15. Pavan P C, Gomes G D A and Valim J B 1998 Microporous. Mesoporous Mater. 21 659. 16. Li P G, Lv F Z, Xu Z X, Qi G G and Zhang Y H 2013 J. Mater. Sci. 48 5437. 17. Saber O and Tagaya H 2003 J. Incl. Phenom. Macrocyclic. Chem.

Effects of montelukast sodium combined with pidotimod on acute phase protein and immune function in children with acute bronchitis

Directory of Open Access Journals (Sweden)

Jing Wang

2017-08-01

Full Text Available Objective: To observe the effects of montelukast sodium combined with pidotimod on acute phase protein (APP and indexes of immunologic function in pediatric acute bronchitis treatment. Methods: A total of 180 cases children with acute bronchitis acted as research objects were randomly divided into control group (n=65 and observation group (n=63. On the basis of conventional therapy, control group was treated by plus pidotimod. On this base, observation group was treated with montelukast sodium. The changes of acute phase proteins (CRP, HP, a1-AAG and CER and immune function (CD3+ , CD4+ , CD8+ and CD4+ /CD8+ levels before and after treatment were observed after 2 months. Results: Before treatment, CRP, HP, a1-AAG, CER, CD3+ , CD4+ , CD8+ and CD4+ /CD8+ levels of two groups had no statistically significant difference; CRP, HP, a1-AAG, CER, and CD8+ levels of control and observation groups decreased significantly after treatment, the decreases of observation group were more obvious than that of control group, and the levels after treatment were significantly lower than that of control groups. The levels of CD3+ , CD4+ and CD4+ /CD8+ in two groups after treatment were significantly higher than those before treatment. For observation group, the levels of CD3+ , CD4+ and CD4+ /CD8+ increased more significantly after treatment, which were significantly higher than that of the control group. Conclusion: Using Montelukast sodium combined with pidotimod can effectively reduce the children's acute phase protein levels, improve immune function, which has clinical value for the treatment of children with acute bronchitis.

Unfolding study of a trimeric membrane protein AcrB.

Science.gov (United States)

Ye, Cui; Wang, Zhaoshuai; Lu, Wei; Wei, Yinan

2014-07-01

The folding of a multi-domain trimeric α-helical membrane protein, Escherichia coli inner membrane protein AcrB, was investigated. AcrB contains both a transmembrane domain and a large periplasmic domain. Protein unfolding in sodium dodecyl sulfate (SDS) and urea was monitored using the intrinsic fluorescence and circular dichroism spectroscopy. The SDS denaturation curve displayed a sigmoidal profile, which could be fitted with a two-state unfolding model. To investigate the unfolding of separate domains, a triple mutant was created, in which all three Trp residues in the transmembrane domain were replaced with Phe. The SDS unfolding profile of the mutant was comparable to that of the wild type AcrB, suggesting that the observed signal change was largely originated from the unfolding of the soluble domain. Strengthening of trimer association through the introduction of an inter-subunit disulfide bond had little effect on the unfolding profile, suggesting that trimer dissociation was not the rate-limiting step in unfolding monitored by fluorescence emission. Under our experimental condition, AcrB unfolding was not reversible. Furthermore, we experimented with the refolding of a monomeric mutant, AcrBΔloop , from the SDS unfolded state. The CD spectrum of the refolded AcrBΔloop superimposed well onto the spectra of the original folded protein, while the fluorescence spectrum was not fully recovered. In summary, our results suggested that the unfolding of the trimeric AcrB started with a local structural rearrangement. While the refolding of secondary structure in individual monomers could be achieved, the re-association of the trimer might be the limiting factor to obtain folded wild-type AcrB. © 2014 The Protein Society.

Chemical composition of protein concentrate prepared from Yellowfin tuna Thunnus albacares roe by cook-dried process

Directory of Open Access Journals (Sweden)

Hyun Ji Lee

2016-05-01

Full Text Available Abstract Roe is the term used to describe fish eggs (oocytes gathered in skeins and is one of the most valuable food products from fishery sources. Thus, means of processing are required to convert the underutilized yellowfin tuna roes (YTR into more marketable and acceptable forms as protein concentrate. Roe protein concentrates (RPCs were prepared by cooking condition (boil-dried concentrate, BDC and steam-dried concentrate, SDC, respectively and un-cooking condition (freeze-dried concentrate, FDC from yellowfin tuna roe. The yield of RPCs was in the range from 22.2 to 25.3 g/100 g of roe. RPCs contained protein (72.3–77.3 %, moisture (4.3–5.6 %, lipid (10.6–11.3 % and ash (4.3–5.7 % as the major constituents. The prominent amino acids of RPCs were aspartic acid, 8.7–9.2, glutamic acid, 13.1–13.2, and leucine, 8.5–8.6 g/100 g of protein. Major differences were not observed in each of the amino acid. K, S, Na, and P as minerals were the major elements in RPCs. No difference noted in sodium dodecyl sulfate polyacrylamide gel electrophoresis protein band (15–100 K possibly representing partial hydrolysis of myosin. Therefore, RPCs from YTR could be use potential protein ingredient for human food and animal feeds.

Adhesion of food-borne bacteria to stainless steel is reduced by food conditioning films

DEFF Research Database (Denmark)

Bernbom, Nete; Ng, Yin; Jorgensen, R.L.

2009-01-01

of proteins with similar molecular weight based in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, in several extracts that reduced adhesion but also extracts not containing this protein reduced bacterial adhesion, indicating that several molecular species may be involved in the phenomenon....... It is a common perception that food materials facilitate bacterial adhesion to surfaces; however, this study demonstrates that aqueous coatings of food origin may actually reduce bacterial adhesion. Compounds from food extracts may potentially be used as nontoxic coatings to reduce bacterial attachment to inert...

Enrichment and Identification of the Most Abundant Zinc Binding Proteins in Developing Barley Grains by Zinc-IMAC Capture and Nano LC-MS/MS

Directory of Open Access Journals (Sweden)

Giuseppe Dionisio

2018-01-01

Full Text Available Background: Zinc accumulates in the embryo, aleurone, and subaleurone layers at different amounts in cereal grains. Our hypothesis is that zinc could be stored bound, not only to low MW metabolites/proteins, but also to high MW proteins as well. Methods: In order to identify the most abundant zinc binding proteins in different grain tissues, we microdissected barley grains into (1 seed coats; (2 aleurone/subaleurone; (3 embryo; and (4 endosperm. Initial screening for putative zinc binding proteins from the different tissue types was performed by fractionating proteins according to solubility (Osborne fractionation, and resolving those via Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE followed by polyvinylidene fluoride (PVDF membrane blotting and dithizone staining. Selected protein fractions were subjected to Zn2+-immobilized metal ion affinity chromatography, and the captured proteins were identified using nanoscale liquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS. Results: In the endosperm, the most abundant zinc binding proteins were the storage protein B-hordeins, gamma-, and D-hordeins, while in the embryo, 7S globulins storage proteins exhibited zinc binding. In the aleurone/subaleurone, zinc affinity captured proteins were late abundant embryogenesis proteins, dehydrins, many isoforms of non-specific lipid transfer proteins, and alpha amylase trypsin inhibitor. Conclusions: We have shown evidence that abundant barley grain proteins have been captured by Zn-IMAC, and their zinc binding properties in relationship to the possibility of zinc storage is discussed.

Prenatal programming of rat cortical collecting tubule sodium transport.

Science.gov (United States)

Cheng, Chih-Jen; Lozano, German; Baum, Michel

2012-03-15

Prenatal insults have been shown to lead to elevated blood pressure in offspring when they are studied as adults. Prenatal administration of dexamethasone and dietary protein deprivation have demonstrated that there is an increase in transporter abundance for a number of nephron segments but not the subunits of the epithelial sodium channel (ENaC) in the cortical collecting duct. Recent studies have shown that aldosterone is elevated in offspring of protein-deprived mothers when studied as adults, but the physiological importance of the increase in serum aldosterone is unknown. As an indirect measure of ENaC activity, we compared the natriuretic response to benzamil in offspring of mothers who ate a low-protein diet (6%) with those who ate a normal diet (20%) for the last half of pregnancy. The natriuretic response to benzamil was greater in the 6% group (821.1 ± 161.0 μmol/24 h) compared with the 20% group (279.1 ± 137.0 μmol/24 h), consistent with greater ENaC activity in vivo (P sodium transport (-1.9 ± 3.1 pmol·mm(-1)·min(-1)), the offspring of rats that ate a 6% protein diet during the last half of pregnancy had a net sodium flux of 10.7 ± 2.6 pmol·mm(-1)·min(-1) (P = 0.01) in tubules perfused in vitro. Sodium transport was measured using ion-selective electrodes, a novel technique allowing measurement of sodium in nanoliter quantities of fluid. Thus we directly demonstrate that there is prenatal programming of cortical collecting duct sodium transport.

Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions

International Nuclear Information System (INIS)

Jhun, E.; Jhun, B.H.; Jones, L.R.; Jung, C.Y.

1991-01-01

The 12 transmembrane alpha helices (TMHs) of human erythrocyte glucose transporter were individually cut by pepsin digestion as membrane-bound 2.5-3.5-kDa peptide fragments. Radiation-induced chemical degradation of these fragments showed an average target size of 34 kDa. This is 10-12 x larger than the average size of an individual TMH, demonstrating that a significant energy transfer occurs among these TMHs in the absence of covalent linkage. Heating this TMH preparation at 100 degree C for 15 min reduced the target size to 5 kDa or less, suggesting that the noncovalent energy transfer requires specific helix-helix interactions. Purified phospholamban, a small (6-kDa) integral membrane protein containing a single TMH, formed a pentameric assembly in sodium dodecyl sulfate. The chemical degradation target size of this phospholamban pentamer was 5-6 kDa, illustrating that not all integral membrane protein assemblies permit intersubunit energy transfer. These findings together with other published observations suggest strongly that significant noncovalent energy transfer can occur within the tertiary and quaternary structure of membrane proteins and that as yet undefined proper molecular interactions are required for such covalent energy transfer. Our results with pepsin-digested glucose transporter also illustrate the importance of the interhelical interaction as a predominating force in maintaining the tertiary structure of a transmembrane protein

Expression of renin-angiotensin system signalling compounds in maternal protein-restricted rats: effect on renal sodium excretion and blood pressure.

Science.gov (United States)

Mesquita, Flávia Fernandes; Gontijo, José Antonio Rocha; Boer, Patrícia Aline

2010-02-01

Intrauterine growth restriction due to low maternal dietary protein during pregnancy is associated with retardation of foetal growth, renal alterations and adult hypertension. The renin-angiotensin system (RAS) is a coordinated hormonal cascade in the control of cardiovascular, renal and adrenal function that governs body fluid and electrolyte balance, as well as arterial pressure. In the kidney, all the components of the renin-angiotensin system including angiotensin II type 1 (AT1) and type 2 (AT2) receptors are expressed locally during nephrogenesis. Hence, we investigated whether low protein diet intake during pregnancy altered kidney and adrenal expression of AT1(R) and AT2(R) receptors, their pathways and if the modified expression of the RAS compounds occurs associated with changes in urinary sodium and in arterial blood pressure in sixteen-week-old males' offspring of the underfed group. The pregnancy dams were divided in two groups: with normal protein diet (pups named NP) (17% protein) or low protein diet (pups LP) (6% protein) during all pregnancy. The present data confirm a significant enhancement in arterial pressure in the LP group. Furthermore, the study showed a significantly decreased expression of RAS pathway protein and Ang II receptors in the kidney and an increased expression in the adrenal of LP rats. The detailed immunohistochemical analysis of RAS signalling proteins in the kidney confirm the immunoblotting results for both groups. The present investigation also showed a pronounced decrease in fractional urinary sodium excretion in maternal protein-restricted offspring, compared with the NP age-matched group. This occurred despite unchanged creatinine clearance. The current data led us to hypothesize that foetal undernutrition could be associated with decreased kidney expression of AT(R) resulting in the inability of renal tubules to handle the hydro-electrolyte balance, consequently causing arterial hypertension.

The Biodiversity of Lactic Acid Bacteria in Greek Traditional Wheat Sourdoughs Is Reflected in Both Composition and Metabolite Formation

OpenAIRE

De Vuyst, Luc; Schrijvers, Vincent; Paramithiotis, Spiros; Hoste, Bart; Vancanneyt, Marc; Swings, Jean; Kalantzopoulos, George; Tsakalidou, Effie; Messens, Winy

2002-01-01

Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria into the species Lactob...

Modulation of epithelial sodium channel trafficking and function by sodium 4-phenylbutyrate in human nasal epithelial cells.

Science.gov (United States)

Prulière-Escabasse, Virginie; Planès, Carole; Escudier, Estelle; Fanen, Pascale; Coste, André; Clerici, Christine

2007-11-23

Sodium 4-phenylbutyrate (4-PBA) has been shown to correct the cellular trafficking of several mutant or nonmutant plasma membrane proteins such as cystic fibrosis transmembrane conductance regulator through the expression of 70-kDa heat shock proteins. The objective of the study was to determine whether 4-PBA may influence the functional expression of epithelial sodium channels (ENaC) in human nasal epithelial cells (HNEC). Using primary cultures of HNEC, we demonstrate that 4-PBA (5 mm for 6 h) markedly stimulated amiloride-sensitive sodium channel activity and that this was related to an increased abundance of alpha-, beta-, and gamma-ENaC subunits in the apical membrane. The increase in ENaC cell surface expression (i) was due to insertion of newly ENaC subunits as determined by brefeldin A experiments and (ii) was not associated with cell surface retention of ENaC subunits because endocytosis of ENaC subunits was unchanged. In addition, we find that ENaC co-immunoprecipitated with the heat shock protein constitutively expressed Hsc70, that has been reported to modulate ENaC trafficking, and that 4-PBA decreased Hsc70 protein level. Finally, we report that in cystic fibrosis HNEC obtained from two cystic fibrosis patients, 4-PBA increased functional expression of ENaC as demonstrated by the increase in amiloride-sensitive sodium transport and in alpha-, beta-, and gamma-ENaC subunit expression in the apical membrane. Our results suggest that in HNEC, 4-PBA increases the functional expression of ENaC through the insertion of new alpha-, beta-, and gamma-ENaC subunits into the apical membrane and also suggest that 4-PBA could modify ENaC trafficking by reducing Hsc70 protein expression.

New fluorescent polymeric nanocomposites synthesized by antimony dodecyl-mercaptide thermolysis in polymer

Directory of Open Access Journals (Sweden)

2009-04-01

Full Text Available In this work, the formation of semiconductive Sb2S3 nanoparticles inside amorphous polystyrene has been achieved by thermal degradation of the corresponding antimony dodecyl-mercaptide, Sb(SC12H253. The thermolysis of the dodecyl-mercaptide precursor was studied as both pure phase and mercaptide solution in polystyrene. The thermal decomposition of the antimony mercaptide precursor at 350°C, under vacuum, showed the formation of a mixture of antimony trisulfide (stibnite, Sb2S3 and zero-valent antimony (Sb phase. X-ray Powder Diffraction (XRD and Rietveld analysis carried out on the obtained nanostructured powder confirmed the presence of Sb and Sb2S3 phases in 10.4 wt% and 89.6 wt% amount, respectively. The same pyrolysis reaction was carried out in the polymer and the resulting nanocomposite material was characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, UV-VIS spectroscopy, and fluorescence spectroscopy. The nanocomposite structural characterization indicated the presence of well-dispersed nanoclusters of antimony and stibnite (15–30 nm in size inside the amorphous polymeric phase. Optical measurements on the obtained nanocomposite films showed a strong emission at 432 nm upon excitation at 371 nm, probably related to the presence of Sb2S3 nanoclusters.

A comparative in vitro study of the digestibility of heat- and high pressure-induced gels prepared from industrial milk whey proteins

Science.gov (United States)

He, Jin-Song; Mu, Tai-Hua; Wang, Juan

2013-06-01

We undertook this study to compare the digestibility of heat- and high pressure-induced gels produced from whey protein isolate (WPI). To simulate in vivo gastrointestinal digestion of WPI gels, a pepsin-trypsin digestion system was used. The in vitro protein digestibility of WPI gels induced by high pressure (400 MPa and 30 min; P-gel) and those induced by heat (80°C and 30 min; H-gel) was compared using a protein concentration of 0.14 g mL-1. The in vitro protein digestibility of P-gels was significantly greater than that of H-gels (p<0.05). The size-exclusion chromatography profiles of the hydrolysates showed that the P-gel generated more and smaller peptides than natural WPI and H-gels. Furthermore, Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed some soluble disulfide-mediated aggregation in the P-gel, while there was more insoluble aggregation in the H-gel than the P-gel. The P-gel was more sensitive to proteinase than the H-gel, which was related to the content of S-S bonds, and this in turn could be attributed to the differences in the gelation mechanism between the H-gel and P-gel.

Stability of milk fat globule membrane proteins toward human enzymatic gastrointestinal digestion.

Science.gov (United States)

Le, T T; Van de Wiele, T; Do, T N H; Debyser, G; Struijs, K; Devreese, B; Dewettinck, K; Van Camp, J

2012-05-01

The milk fat globule membrane (MFGM) fraction refers to the thin film of polar lipids and membrane proteins that surrounds fat globules in milk. It is its unique biochemical composition that renders MFGM with some beneficial biological activities, such as anti-adhesive effects toward pathogens. However, a prerequisite for the putative bioactivity of MFGM is its stability during gastrointestinal digestion. We, therefore, subjected MFGM material, isolated from raw milk, to an in vitro enzymatic gastrointestinal digestion. Sodium dodecyl sulfate PAGE, in combination with 2 staining methods, Coomassie Blue and periodic acid Schiff staining, was used to evaluate polypeptide patterns of the digest, whereas mass spectrometry was used to confirm the presence of specific MFGM proteins. Generally, it was observed that glycoproteins showed higher resistance to endogenous proteases compared with non-glycosylated proteins. Mucin 1 displayed the highest resistance to digestion and a considerable part of this protein was still detected at its original molecular weight after gastric and small intestine digestion. Cluster of differentiation 36 was also quite resistant to pepsin. A significant part of periodic acid Schiff 6/7 survived the gastric digestion, provided that the lipid moiety was not removed from the MFGM material. Overall, MFGM glycoproteins are generally more resistant to gastrointestinal digestion than serum milk proteins and the presence of lipids, besides glycosylation, may protect MFGM glycoproteins from gastrointestinal digestion. This gastrointestinal stability makes MFGM glycoproteins amenable to further studies in which their putative health-promoting effects can be explored. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Finding the "bio" in biobased products: electrophoretic identification of wheat proteins in processed products.

Science.gov (United States)

Robertson, George H; Hurkman, William J; Cao, Trung K; Tanaka, Charlene K; Orts, William J

2010-04-14

Verification of the biocontent in biobased or "green" products identifies genuine products, exposes counterfeit copies, supports or refutes content claims, and ensures consumer confidence. When the biocontent includes protein, elemental nitrogen analysis is insufficient for verification since non-protein, but nitrogen-rich, content also may be present. However, the proteins can be extracted, separated by electrophoretic methods, and detected by UV absorption, protein stain, or immunoblotting. We utilized capillary zone electrophoresis (CZE) to separate proteins in a gliadin fraction that had been dissolved in aqueous ethanol (70%) and polyacrylamide gel electrophoresis (PAGE) to separate proteins in a gliadin-plus-glutenin fraction that had been dissolved in water containing both sodium dodecyl sulfate (SDS) and a reducing agent, dithiothreitol (DTT). We sought to verify the presence of these wheat grain proteins in wheat bread, a wheat flake cereal, wheat beer, and an enclosure for an antique automobile ignition coil reputed to contain wheat gluten. Proteins extracted from commercial wheat, corn, and soy flours served as standards, and proteins from heat-altered wheat served as process condition references. This approach successfully identified wheat proteins in these products especially if the process temperature did not exceed 120 degrees C. Above this temperature attenuation was nearly complete for proteins analyzed by CZE, but wheat-like patterns could still be recognized by one- and two-dimensional PAGE. Immunoblots reacted with grain-specific antibodies confirmed the identities of the cereal component especially when the protein pattern was greatly altered by thermal modification, specific protein adsorption, or protein digestion. In addition to verifying that wheat proteins are present, the complementary use of these methods can reveal whether whole wheat gluten or merely an alcohol-soluble fraction had been used in the specific product and indicate the

Identification and Characterization of Main Allergic Proteins in Cooked Wolf Herring Fish.

Science.gov (United States)

Mohamadi, Mohsen; Falak, Reza; Mokhtarian, Kobra; Khoramizadeh, Mohammad Reza; Sadroddiny, Esmaeil; Kardar, Gholam Ali

2016-10-01

Our aim in this study was to identify and characterize allergic proteins in cooked wolf herring fish. We heated the crude extract alternatively at 50, 60, 70, 80, 90, and 100°C for one hour and results were compared by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Also, proteins were immunoblotted with fish-sensitive patients' sera. The major allergenic proteins were identified via mass spectrometry. These allergenic proteins were then purified by anion exchange chromatography and the IgE-immunoreactivity of the fractions was compared with the crude extracts via disk enzyme-linked immunosorbent assay (ELISA). SDS-PAGE of the crude extract showed more than 15 distinct protein bands. Five of these proteins, with apparent molecular weights of 12, 18, 24, 38, and 51 kDa, were only observed in the 100°C heated extract. Immunoblotting of the heated extract revealed that the 12 and 51 kDa proteins were IgE-immunoreactive with 88 percent of fish-sensitive patient sera while the 24 and 38 kDa proteins reacted with 33.3 and 55.5 percent of fish-sensitive patient sera, respectively. Mass spectrometry of the 12, 38, and 51 kDa proteins revealed that all three were parvalbumin oligomers. Disk ELISA results showed that 20 of 25 and 14 of 25 fish-allergic patients' sera were IgE-reactive with purified oligomeric parvalbumin-coated and crude extract-coated disks, respectively. Parvalbumin and its oligomers are the main allergenic molecules in cooked fish. Therefore, an enriched or purified fraction containing this protein could be a useful source of allergen for applications in ELISA-based immunoassays and could discriminate fish-allergic patients who can tolerate cooked fish from those who cannot.