scholarly journals Partial Chemical Characterization of S-Carboxymethylated Chains of Rabbit Fibrin(OGEN): Evidence for Separate Chain Biosynthesis

1977 ◽  
Author(s):  
B. Alving ◽  
G. Murano ◽  
D. Walz

The purpose of this study was twofold: 1) chemically characterize the isolated polypeptide chains of rabbit fibrin(ogen), and 2) explore their mode of biosynthesis. The three S-carboxy-methyl polypeptide chain derivatives of rabbit fibrin (α, β and γ) were isolated by cation exchange chromatography. Their amino acid composition was similar to the human with a methionine distribution (mole/mole) as follows: γ = 9; β = 14, α = 14. Their molecular size, (SDS electrophoresis) was estimated as follows: γ = 46,000; β = 54,000; α = 63,500. The N-terminal amino acid sequence (12 steps) of the β derivative was:Gly-His-Arg-Pro-Ile-Asp-Arg-Arg-Arg-Glu-Glu-Leu-. To determine whether the three chains are synthesized sequentially (one continuous chain, later split into three) or in parallel, turpentine-stimulated male New Zealand rabbits were given ~40 μCi of [75Se] selenomethionine (SeM) and its incorporation into fibrinogen (F) was followed. F was clotted from plasma samples, washed, reduced, and constituent chains separated by gel electrophoresis in the presence of SDS-urea. The radioactivity of each chain (expressed as percent of total F radioactivity) was determined, and the specific methionine radioactivity calculated for each chain isolated at 20, 25, and 30 min after SeM injection. During this interval the specific activity of the α and the γ chains was essentially the same (within 3%) while that of the β chain was 42 to 97% greater than that of the α chain. The similar activity of the α and γ chains during the early phase of SeM incorporation suggests that these two chains are not synthesized sequentially, rather they are synthesized in parallel.

1973 ◽  
Vol 74 (2) ◽  
pp. 226-236 ◽  
Author(s):  
Michel Chrétien ◽  
Claude Gilardeau

ABSTRACT A protein isolated from ovine pituitary glands has been purified, and its homogeneity assessed by NH2- and COOH-terminal amino acid determination, ultracentrifugation studies, and polyacrylamide gel electrophoresis after carboxymethylation. Its chemical and immunochemical properties are closely similar to those of beef and pork neurophysins, less similar to those of human neurophysins. It contains no tryptophan (like other neurophysins) or histidine (like all except bovine neurophysin-I and human neurophysins). It has alanine at the NH2-terminus and valine at the COOH-terminus. Its amino acid composition is similar to, but not identical with those of porcine and bovine neurophysins.


2021 ◽  
Vol 11 (7) ◽  
pp. 3212
Author(s):  
Noa Miguez ◽  
Peter Kidibule ◽  
Paloma Santos-Moriano ◽  
Antonio O. Ballesteros ◽  
Maria Fernandez-Lobato ◽  
...  

Chitooligosaccharides (COS) are homo- or hetero-oligomers of D-glucosamine (GlcN) and N-acetyl-D-glucosamine (GlcNAc) that can be obtained by chitosan or chitin hydrolysis. Their enzymatic production is preferred over other methodologies (physical, chemical, etc.) due to the mild conditions required, the fewer amounts of waste and its efficiency to control product composition. By properly selecting the enzyme (chitinase, chitosanase or nonspecific enzymes) and the substrate properties (degree of deacetylation, molecular weight, etc.), it is possible to direct the synthesis towards any of the three COS types: fully acetylated (faCOS), partially acetylated (paCOS) and fully deacetylated (fdCOS). In this article, we review the main strategies to steer the COS production towards a specific group. The chemical characterization of COS by advanced techniques, e.g., high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and MALDI-TOF mass spectrometry, is critical for structure–function studies. The scaling of processes to synthesize specific COS mixtures is difficult due to the low solubility of chitin/chitosan, the heterogeneity of the reaction mixtures, and high amounts of salts. Enzyme immobilization can help to minimize such hurdles. The main bioactive properties of COS are herein reviewed. Finally, the anti-inflammatory activity of three COS mixtures was assayed in murine macrophages after stimulation with lipopolysaccharides.


Author(s):  
Ismat Bibi ◽  
Haq Nawaz Bhatti

This study deals with purification and characterization of lignin peroxidase (LiP) isolated from Agaricus bitorqus A66 during decolorization of NOVASOL Direct Black dye. A laboratory scale experiment was conducted for maximum LiP production under optimal conditions. Purification & fractionation of LiP was performed on DEAE-Sepharose ion exchange chromatography followed by Sephadex G-50 gel filtration. The purified LiP has a specific activity of 519 U/mg with 6.73% activity recover. The optimum pH and temperature of purified LiP for the oxidation of veratryl alcohol were 6.8 and 45 °C, respectively. Michaelis-Menten kinetic constants (Vmax and Km) were determined using different concentrations of veratryl alcohol (1-35 mM). The Km and Vmax were 16.67 mM and 179.2 U/mL respectively, for veratryl alcohol oxidation as determined from the Lineweaver-Burk plot. Thermal inactivation studies were carried out at different temperatures to check the thermal stability of the enzyme. Enthalpy of activation decreased where Free energy of activation for thermal denaturation increased at higher temperatures. A possible explanation for the thermal inactivation of LiP at higher temperatures is also discussed.


2021 ◽  
Author(s):  
Amrutha Bindu ◽  
Lakshmi Devi

Abstract The focus of present study was to characterize antimicrobial peptide produced by probiotic cultures, Enterococcus durans DB-1aa (MCC4243), Lactobacillus plantarum Cu2-PM7 (MCC4246) and Lactobacillus fermentum Cu3-PM8 (MCC4233) against Staphylococus aureus and E. coli. The growth kinetic assay revealed 24 h of incubation to be optimum for bacteriocin production. The partially purified compound after ion-exchange chromatography was found to be thermoresistant and stable under wide range of pH. The compound was sensitive to proteinase-K, but resistant to trypsin, a-amylase and lipase. The apparent molecular weight of bacteriocin from MCC4243 and MCC4246 was found to be 3.5 KDa. Translated partial amino acid sequence of plnA gene in MCC4246 displayed 48 amino acid sequences showing 100% similarity with plantaricin A of Lactobacillus plantarum (WP_0036419). The sequence revealed 7 β sheets, 6 α sheets, 6 predicted coils and 9 predicted turns. The functions on cytoplasm show 10.82 isoelectric point and 48.6% hydrophobicity. The molecular approach of using Geneious Prime software and protein prediction data base for characterization of bacteriocin is novel and predicts “KSSAYSLQMGATAIKQVKKLFKKWGW” as peptide responsible for antimicrobial activity. The study provides information about broad spectrum bacteriocin in native probiotic culture and paves a way towards its application in functional foods as biopreservative agents.


2017 ◽  
Vol 18 (2) ◽  
pp. 1-10 ◽  
Author(s):  
Dzun Noraini Jimat ◽  
Intan Baizura Firda Mohamed ◽  
Azlin Suhaida Azmi ◽  
Parveen Jamal

A newly bacterial producing L-asparaginase was successful isolated from Sungai Klah Hot Spring, Perak, Malaysia and identified as Bacillus sp. It was the best L-asparaginase producer as compared to other isolates. Production of L-asparaginase from the microbial strain was carried out under liquid fermentation. The crude enzyme was then centrifuged and precipitated with ammonium sulfate before further purified with chromatographic method. The ion exchange chromatography HiTrap DEAE-Sepharose Fast Flow column followed by separation on Superose 12 gel filtration were used to obtain pure enzyme. The purified enzyme showed 10.11 U/mg of specific activity, 50.07% yield with 2.21 fold purification. The purified enzyme was found to be dimer in form, with a molecular weight of 65 kDa as estimated by SDS-PAGE. The maximum activity of the purified L-asparaginase was observed at pH 9 and temperature of 60°C.


2013 ◽  
Vol 10 (3) ◽  
pp. 844-853
Author(s):  
Baghdad Science Journal

Endoglucanase produced from Aspergillus flavus was purified by several steps including precipitation with 25 % ammonium sulphate followed by Ion –exchange chromatography, the obtained specific activity was 377.35 U/ mg protein, with a yield of 51.32 % .This step was followed by gel filtration chromatography (Sepharose -6B), when a value of specific activity was 400 U/ mg protein, with a yield of 48 %. Certain properties of this purified enzyme were investigated, the optimum pH of activity was 7 and the pH of its stability was 4.5, while the temperature stability was 40 °C for 60 min. The enzyme retained 100% of its original activity after incubation at 40 °C for 60 min; the optimum temperature for enzyme activity was 40 °C.


Blood ◽  
1968 ◽  
Vol 31 (5) ◽  
pp. 623-632 ◽  
Author(s):  
CON S. REED ◽  
ROGER HAMPSON ◽  
SUSAN GORDON ◽  
RICHARD T. JONES ◽  
MILES J. NOVY ◽  
...  

Abstract An abnormal hemoglobin, termed hemoglobin Kempsey, was found in association with erythrocytosis in ten members of an Australian family. Genetic transmission fits an autosomal dominant pattern. Chemical characterization of hemoglobin Kempsey identified a single amino acid substitution, β99Asp→Asn. Properties of hemoglobin Kempsey include a marked increase in oxygen affinity, retention of the Bohr effect, and decreased heme-heme interaction. Possible structure-function relations of this and other abnormal hemoglobins associated with erythrocytosis are discussed.


2005 ◽  
Vol 37 (6) ◽  
pp. 363-370 ◽  
Author(s):  
Ye-Yun Li ◽  
Chang-Jun Jiang ◽  
Xiao-Chun Wan ◽  
Zheng-Zhu Zhang ◽  
Da-Xiang Li

Abstractβ-Glucosidases are important in the formation of floral tea aroma and the development of resistance to pathogens and herbivores in tea plants. A novel β-glucosidase was purified 117-fold to homogeneity, with a yield of 1.26%, from tea leaves by chilled acetone and ammonium sulfate precipitation, ion exchange chromatography (CM-Sephadex C-50) and fast protein liquid chromatography (FPLC; Superdex 75, Resource S). The enzyme was a monomeric protein with specific activity of 2.57 U/mg. The molecular mass of the enzyme was estimated to be about 41 kDa and 34 kDa by SDS-PAGE and FPLC gel filtration on Superdex 200, respectively. The enzyme showed optimum activity at 50 °C and was stable at temperatures lower than 40 °C. It was active between pH 4.0 and pH 7.0, with an optimum activity at pH 5.5, and was fairly stable from pH 4.5 to pH 8.0. The enzyme showed maximum activity towards pNPG, low activity towards pNP-Galacto, and no activity towards pNP-Xylo.


1982 ◽  
Vol 156 (2) ◽  
pp. 550-566 ◽  
Author(s):  
S M Goyert ◽  
J E Shively ◽  
J Silver

In mice, two families of structurally distinct Ia molecules, one designated I-A and the other I-E, have been identified and characterized. The HLA-DR molecules represent one family of human Ia molecules equivalent to the murine I-E molecules on the basis of amino acid sequence homology. We describe the isolation and biochemical characterization of a second family of human Ia molecules, designated HLA-DS for second D-region locus, equivalent to the murine I-A molecules. The human HLA-DS molecules consist of two polypeptide chains, DS alpha (37,000 mol wt) and DS beta (29,000 mol wt), with 73% amino acid sequence identity to the murine I-A molecules. Furthermore, the HLA-DS molecules are closely linked genetically to HLA-DR molecules, a situation analogous to that observed in mice. The similarity in molecular weights of the DR and DS molecules might explain why others have failed to identify the latter in man.


2010 ◽  
Vol 5 (6) ◽  
pp. 1934578X1000500
Author(s):  
Hidayatullah Khan ◽  
Irshad Ali ◽  
Arif-ullah Khan ◽  
Mushtaq Ahmed ◽  
Zamarud Shah ◽  
...  

A high molecular weight serine protease has been purified to electrophoretic homogeneity from the seeds of Caesalpinia bonducella Flem. (Caesalpiniaceae) by the combination of size exclusion and ion exchange chromatography. About 524 fold purification was achieved with an overall recovery of 6.8%. The specific activity was found to be 86 U/mg/min at pH 8.0. The calculated Km and Vmax were 1.66 mg/mL and 496.68 units/min per mg of protein, respectively. The molecular mass was estimated to be about 63 kDa by sodium dodecyl sulfate PAGE. The enzyme showed optimum activity at pH 8.0 and exhibited its highest activity at 40°C. The enzyme was strongly inhibited by 2mM phenylmethylsulfonyl fluoride (PMSF), suggesting the presence of a serine residue at the active site. PMSF showed a pure competitive type of inhibition with the serine protease enzyme. It was observed that enzyme activity was enhanced in the presence of dications and was active against a variety of modified substrates and natural proteins.


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