Isolation and preliminary characterization of histone H1.b allelic variants from quail erythrocytes

Genome ◽  
1998 ◽  
Vol 41 (5) ◽  
pp. 709-719 ◽  
Author(s):  
Jan Palyga ◽  
James M Neelin

Our goal was to purify and characterize the allelic variants H1b1 and H1b2 of histone H1.b, one of the seven subtypes of this linker histone extracted from Japanese quail erythrocyte nuclei. These variants are revealed phenotypically as band H1.3 or part of band H1.4 by polyacrylamide gel electrophoresis (PAGE) in sodium dodecyl sulfate (SDS). All H1 subtypes together were separated from H5 by gel-permeation chromatography through Bio-Gel P-150. H1 was then fractionated on a column of the cation-exchange resin Amberlite CG-50 by using a shallow guanidine hydrochloride gradient, which enriched subtype H1.b together with H1.z and overlapping with subtypes H1.a and H1.b. Alternatively purification of subtypes was achieved electrophoretically: total H1 fractions from quail with different H1 phenotypes were first resolved into sub-types by PAGE in acetic acid - urea; after staining, the appropriate H1.b bands from several parallel gel pieces were excised and the histone was concentrated by PAGE in SDS. After fragmentation of H1.b in the gel pieces with N-bromosuccinimide (NBS), PAGE in SDS indicated no difference between H1b1 and H1b2 in the C-terminal "half" of the polypeptides. In contrast, limited digestion with endoprotease V8 from Staphylococcus aureus has shown that differences, probably by a few residues in length, reside in the N-terminal part of the molecule, close to the amino-terminus.Key words: quail histone H1.b, electrophoretic fractionation, linker histone variant.

1986 ◽  
Vol 239 (3) ◽  
pp. 699-704 ◽  
Author(s):  
S Chaudhuri ◽  
J M Lambert ◽  
L A McColl ◽  
J R Coggins

A procedure has been developed for the purification of 3-dehydroquinase from Escherichia coli. Homogeneous enzyme with specific activity 163 units/mg of protein was obtained in 19% overall yield. The subunit Mr estimated from polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate was 29,000. The native Mr, estimated by gel permeation chromatography on Sephacryl S-200 (superfine) and on TSK G3000SW, was in the range 52,000-58,000, indicating that the enzyme is dimeric. The catalytic properties of the enzyme have been determined and shown to be very similar to those of the biosynthetic 3-dehydroquinase component of the arom multifunctional enzyme of Neurospora crassa.


1984 ◽  
Vol 30 (9) ◽  
pp. 1171-1178 ◽  
Author(s):  
C. R. Mackenzie ◽  
D. Bilous ◽  
K. G. Johnson

Streptomyces flavogriseus, a mesophilic actinomycete, produces high levels of extracellular enzymes capable of hydrolyzing cellulose and xylan. One such enzyme, an exoglucanase, has been purified to molecular homogeneity by a sequence involving DEAE Bio-Gel A chromatography, gel permeation chromatography on Bio-Gel P-60, preparative isoelectric focusing, and concanavalin A affinity chromatography. This purification sequence disclosed the presence of several distinct endoglucanase and xylanase fractions. Homogeneity of the purified enzyme was demonstrated by analytical isoelectric focusing and sodium dodecyl sulphate – polyacrylamide gel electrophoresis. The purified enzyme had a molecular weight of approximately 45 000 and an isoelectric point of 4.15. The enzyme demonstrated negligible activity with carboxymethylcellulose as the substrate. It was able to extensively hydrolyse acid-swollen cellulose; the main product of enzyme action was cellobiose.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Jianghao Du ◽  
Zhanyun Zhu ◽  
Junchang Yang ◽  
Jia Wang ◽  
Xiaotong Jiang

AbstractIn this paper, a comparative study was conducted on the extraction effects of six agents for collagen-based mural painting binders. These agents were used to extract the residual proteins in the non-aged and thermal aged samples. The protein extraction efficiencies of different extracting agents were quantitatively determined by bicinchoninic acid (BCA) method, and then processed by multivariate analysis of variance (MANOVA). The impact of the extraction process on the protein structure was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), ultraviolet absorption spectrum (UV) and circular dichroism (CD). The results showed that, for both non-aged and aged samples, the extraction efficiency of 2 M guanidine hydrochloride (GuHCl) was significantly higher than the other five agents, with less damage to the protein structure during the extraction process.


Author(s):  
Preeti Anand ◽  
Jay Prakash Pandey ◽  
Dev Mani Pandey

Abstract Background Cocoonase is a proteolytic enzyme that helps in dissolving the silk cocoon shell and exit of silk moth. Chemicals like anhydrous Na2CO3, Marseille soap, soda, ethylene diamine and tartaric acid-based degumming of silk cocoon shell have been in practice. During this process, solubility of sericin protein increased resulting in the release of sericin from the fibroin protein of the silk. However, this process diminishes natural color and softness of the silk. Cocoonase enzyme digests the sericin protein of silk at the anterior portion of the cocoon without disturbing the silk fibroin. However, no thorough characterization of cocoonase and sericin protein as well as imaging analysis of chemical- and enzyme-treated silk sheets has been carried out so far. Therefore, present study aimed for detailed characterization of cocoonase and sericin proteins, phylogenetic analysis, secondary and tertiary structure prediction, and computational validation as well as their interaction with other proteins. Further, identification of tasar silkworm (Antheraea mylitta) pupa stage for cocoonase collection, its purification and effect on silk sheet degumming, scanning electron microscope (SEM)-based comparison of chemical- and enzyme-treated cocoon sheets, and its optical coherence tomography (OCT)-based imaging analysis have been investigated. Various computational tools like Molecular Evolutionary Genetics Analysis (MEGA) X and Figtree, Iterative Threading Assembly Refinement (I-TASSER), self-optimized predicted method with alignment (SOPMA), PROCHECK, University of California, San Francisco (UCSF) Chimera, and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) were used for characterization of cocoonase and sericin proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), protein purification using Sephadex G 25-column, degumming of cocoon sheet using cocoonase enzyme and chemical Na2CO3, and SEM and OCT analysis of degummed cocoon sheet were performed. Results Predicted normalized B-factors of cocoonase and sericin with respect to α and β regions showed that these regions are structurally more stable in cocoonase while less stable in sericin. Conserved domain analysis revealed that B. mori cocoonase contains a trypsin-like serine protease with active site range 45 to 180 query sequences while substrate binding site from 175 to 200 query sequences. SDS-PAGE analysis of cocoonase indicated its molecular weight of 25–26 kDa. Na2CO3 treatment showed more degumming effect (i.e., cocoon sheet weight loss) as compared to degumming with cocoonase. However, cocoonase-treated silk cocoon sheet holds the natural color of tasar silk, smoothness, and luster compared with the cocoon sheet treated with Na2CO3. SEM-based analysis showed the noticeable variation on the surface of silk fiber treated with cocoonase and Na2CO3. OCT analysis also exemplified the variations in the cross-sectional view of the cocoonase and Na2CO3-treated silk sheets. Conclusions Present study enlightens on the detailed characteristics of cocoonase and sericin proteins, comparative degumming activity, and image analysis of cocoonase enzyme and Na2CO3 chemical-treated silk sheets. Obtained findings illustrated about use of cocoonase enzyme in the degumming of silk cocoon at larger scale that will be a boon to the silk industry.


1977 ◽  
Vol 23 (3) ◽  
pp. 240-252 ◽  
Author(s):  
J. Boisvert ◽  
T. Yamamoto

Vaccinia virus particles were dissociated into their constituent polypeptides and analysed by sodium dodecyl sulfate (SDS) gel electrophoresis. Thirty-three distinct polypeptide bands were identified and their molecular weights ranged between 11 000 and 150 000 daltons.Specific staining of gels containing polypeptides of dissociated virions revealed the presence of eight glycopeptides. No lipopeptides were detected.Analysis of chemical extracts (urea, guanidine hydrochloride, and alkali treatment) of the virus by SDS gel electrophoresis indicated that a total of 10 to 14 different polypeptides ranging in molecular weights from 11 000 to 70 000 daltons were solubilized.Analysis of detergent extracts and of the remains of extracted viral particles has shown that the detergent Nonidet P-40 (NP-40) solubilized a total of 11 polypeptides of which 6 were glycopeptides. The other detergents sodium deoxycholate (SDC) and cetyl trimethyl ammonium bromide (CTAB) were not as selective, both solubilizing more than 25 of the polypeptides composing the virus. Gel electrophoresis results also indicated that most of the small molecular weight (11 000–70 000 daltons) polypeptides were readily solubilized by NP-40, SDC, and CTAB, while those with molecular weights of 70 000 daltons and higher were not well solubilized.The effects of detergents were also analysed by electron microscopy. Evidence was obtained for subpopulations of viral particles having different susceptibility to detergent extraction.


2000 ◽  
Vol 66 (1) ◽  
pp. 252-256 ◽  
Author(s):  
Katsuichi Saito ◽  
Kazuya Kondo ◽  
Ichiro Kojima ◽  
Atsushi Yokota ◽  
Fusao Tomita

ABSTRACT Streptomyces exfoliatus F3-2 produced an extracellular enzyme that converted levan, a β-2,6-linked fructan, into levanbiose. The enzyme was purified 50-fold from culture supernatant to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of this enzyme were 54,000 by SDS-PAGE and 60,000 by gel filtration, suggesting the monomeric structure of the enzyme. The isoelectric point of the enzyme was determined to be 4.7. The optimal pH and temperature of the enzyme for levan degradation were pH 5.5 and 60°C, respectively. The enzyme was stable in the pH range 3.5 to 8.0 and also up to 50°C. The enzyme gave levanbiose as a major degradation product from levan in an exo-acting manner. It was also found that this enzyme catalyzed hydrolysis of such fructooligosaccharides as 1-kestose, nystose, and 1-fructosylnystose by liberating fructose. Thus, this enzyme appeared to hydrolyze not only β-2,6-linkage of levan, but also β-2,1-linkage of fructooligosaccharides. From these data, the enzyme from S. exfoliatus F3-2 was identified as a novel 2,6-β-d-fructan 6-levanbiohydrolase (EC 3.2.1.64 ).


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