scholarly journals Chemical identity of tryptensin with angiotensin

1980 ◽  
Vol 187 (3) ◽  
pp. 647-653 ◽  
Author(s):  
K Arakawa ◽  
M Yuki ◽  
M Ikeda

Tryptensin, a vasopressor substance generated from human plasma protein fraction IV-4 by trypsin, has been isolated and the amino acid composition analysed. The procedures used for the isolation were: (a) adsorption of the formed tryptensin on Dowex 50W (X2; NH4+ form); (b) gel filtration through Sephadex G-25; (c) cation-exchange chromatography on CM-cellulose; (d) anion-exchange chromatography on DEAE-cellulose; (e) re-chromatography on CM-cellulose; (f) gel filtration on Bio-Gel P-2; (g) partition chromatography on high-pressure liquid chromatography. The homogeneity of the isolated tryptensin was confirmed by thin-layer chromatography and thin-layer electrophoresis. The amino acid analysis of the hydrolysate suggested the following proportional composition: Asp, 1; Val, 1; Ile, 1; Tyr, 1; Phe, 1; His, 1; Arg, 1; Pro, 1. This composition is identical with that of human angiotensin.

1980 ◽  
Vol 33 (3) ◽  
pp. 279 ◽  
Author(s):  
RN Murdoch ◽  
Louise E Buxton ◽  
DJ Kay

An improved procedure for the purification of alkaline phosphatase from about 10 g of day 7 pregnant mouse uterine tissue is described. Following homogenization, the procedure involved solubilization and extraction with 0�8% (v/v) Triton X-lOO and 20% (v/v) n-butanol, ammonium sulfate precipitation, concanavalin A-Sepharose 4B affinity chromatography, DEAE-cellulose anion-exchange chromatography and Sephacryl S200 gel filtration. On subjecting 2162-fold purified enzyme preparations to polyacrylamide-gel electrophoresis, a single band of protein coincident with the zone of enzyme activity and having an apparent molecular weight of 205 OOO� lOOOO was identified. Affinity chromatography yielded the largest increase in purity of any step in the procedure and established the glycoprotein nature of the uterine enzyme.


1969 ◽  
Vol 47 (12) ◽  
pp. 1103-1107 ◽  
Author(s):  
W. M. Johnson ◽  
D. W. S. Westlake

Active cell-free extracts of Peptococcus aerogenes were prepared which metabolized glutamic acid to α-hydroxyglutaric acid. Factors affecting the formation of this intermediate were studied by following the conversion of glutamic acid labelled with 14C in the one or five positions. The results of these experiments revealed that the production of α-hydroxyglutaric acid from glutamic acid by cell-free extracts was NAD-dependent. The labelled α-hydroxyglutaric acid produced by NAD-supplemented extracts was purified by anion exchange chromatography and identified by several methods including paper and thin-layer chromatography, mass spectrometry, and infrared spectroscopy. A pathway has been proposed for the conversion of glutamic acid to α-hydroxyglutaric acid by cell-free extracts of P. aerogenes.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Jian Sun ◽  
Tzi-Bun Ng ◽  
Hexiang Wang ◽  
Guoqing Zhang

Little was known about bioactive compounds from the hallucinogenic mushroomBoletus speciosus. In the present study, a hemagglutinin (BSH,B. speciosushemagglutinin) was isolated from its fruiting bodies and enzymatic properties were also tested. The chromatographic procedure utilized comprised anion exchange chromatography on Q-Sepharose, cation exchange chromatography on CM-Cellulose, cation exchange chromatography on SP-Sepharose, and gel filtration by FPLC on Superdex 75. The hemagglutinin was a homodimer which was estimated to be approximately 31 kDa in size. The activity of BSH was stable up to 60°C, while there was a precipitous drop in activity when the temperature was elevated to 70°C. BSH retained 25% hemagglutinating activity when exposed to 100 mM NaOH and 25 mM HCl. The activity was potently inhibited by 1.25 mM Hg2+and slightly inhibited by Fe2+, Ca2+, and Pb2+. None of the sugars tested showed inhibition towards BSH. Its hemagglutinating activity towards human erythrocytes type A, type B, and type AB was higher than type O. The hemagglutinin showed antiproliferative activity towards hepatoma Hep G2 cells and mouse lymphocytic leukemia cells (L1210)in vitro, with IC50of 4.7 μM and 7.0 μM, respectively. It also exhibited HIV-1 reverse transcriptase inhibitory activity with an IC50of 7.1 μM.


2001 ◽  
Vol 354 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Ying-Ming WANG ◽  
Suei-Rong WANG ◽  
Inn-Ho TSAI

The major coagulating fibrinogenase of Deinagkistrdon acutus venom, designated acutobin, was purified by anion-exchange chromatography, gel filtration and reverse-phase HPLC. Approximately 80% of its protein sequence was determined by sequencing the various fragments derived from CNBr cleavage and digestion with endoprotease. Extensive screening of the venom gland cDNA species after amplification by PCR resulted in the isolation of four distinct cDNA clones encoding acutobin and three other serine proteases, designated Dav-PA, Dav-KN and Dav-X. The complete amino acid sequences of these enzymes were deduced from the cDNA sequences. The amino-acid sequence of acutobin contains a single chain of 236 residues including four potential N-glycosylation sites. The purified acutobin (40kDa) contains approx. 30% carbohydrate by weight, which could be partly removed by N-glycanase. The phylogenetic tree of the complete amino acid sequences of 40 serine proteases from 18 species of Crotalinae shows functional clusters reflecting parallel evolution of the three major venom enzyme subtypes: coagulating enzymes, kininogenases and plasminogen activators. The possible structural elements responsible for the functional specificity of each subtype are discussed.


1987 ◽  
Vol 65 (10) ◽  
pp. 899-908 ◽  
Author(s):  
F. Moranelli ◽  
M. Yaguchi ◽  
G. B. Calleja ◽  
A. Nasim

The extracellular α-amylase activity of the yeast Schwanniomyces alluvius has been purified by anion-exchange chromatography on DEAE-cellulose and gel-filtration chromatography on Sephadex G-100. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE) and N-terminal amino acid analysis of the purified sample indicated that the enzyme preparation was homogeneous. The enzyme is a glycoprotein having a molecular mass of 52 kilodaltons (kDa) estimated by SDS–PAGE and 39 kDa by gel filtration on Sephadex G-100. Chromatofocusing shows that it is an acidic protein. It is resistant to trypsin but sensitive to proteinase K. Its activity is inhibited by the divalent cation chelators EDTA and EGTA and it is insensitive to sulfhydryl-blocking agents. Exogenous divalent cations are inhibitory as are high concentrations of monovalent salts. The enzyme has a pH optimum between 3.75 and 5.5 and displays maximum stability in the pH range of 4.0–7.0. Under the conditions tested, the activity is maximal between 45 and 50 °C and is very thermolabile. Analysis of its amino acid composition supports its acidic nature.


1992 ◽  
Vol 38 (9) ◽  
pp. 891-897 ◽  
Author(s):  
Hiroshi Tsujibo ◽  
Yukio Yoshida ◽  
Katsushiro Miyamoto ◽  
Chiaki Imada ◽  
Yoshiro Okami ◽  
...  

Chitinase (EC 3.2.1.14) was isolated from the culture supernatant of a marine bacterium, Alteromonas sp. strain O-7. The enzyme (Chi-A) was purified by anion-exchange chromatography (DEAE-Toyopearl 650 M) and gel filtration (Sephadex G-100). The purified enzyme showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular size and pI of Chi-A were 70 kDa and 3.9, respectively. The optimum pH and temperature of Chi-A were 8.0 and 50 °C, respectively. Chi-A was stable in the range of pH 5–10 up to 40 °C. Among the main cations, such as Na+, K+, Mg2+, and Ca2+, contained in seawater, Mg2+ stimulated Chi-A activity. N-Bromosuccinimide and 2-hydroxy-5-nitrobenzyl bromide inhibited Chi-A activity. The amino-terminal 27 amino acid residues of Chi-A were sequenced. This enzyme showed sequence homology with chitinases from terrestrial bacteria such as Serratia marcescens QMB1466 and Bacillus circulons WL-12. Key words: marine bacterium, Alteromonas sp., chitinase.


1974 ◽  
Vol 52 (11) ◽  
pp. 1067-1072 ◽  
Author(s):  
P. Brazeau ◽  
W. Vale ◽  
R. Burgus ◽  
R. Guillemin

Isolation of somatostatin, a tetradecapeptide of ovine origin inhibiting somatotropin secretion, is reported. About 490 000 hypothalamic fragments were submitted to alcohol–chloroform extraction, countercurrent distribution, ion-exchange chromatography, gel filtration, and partition chromatography. Of the 8.5 mg material thus obtained, 77% was accounted for by a peptide shown homogeneous by electrophoresis, thin-layer chromatography, and amino acid analysis. The peptide inhibits the secretion of radioimmunoassayable growth hormone at doses of ≥ 1.0 nM in vitro and 400 ng per rate in vivo.


2019 ◽  
Vol 7 (12) ◽  
pp. 605 ◽  
Author(s):  
Yun Jiang ◽  
Chao Ran ◽  
Lin Chen ◽  
Wang Yin ◽  
Yang Liu ◽  
...  

Endophyte Bacillus methylotrophicus NJ13 was isolated from Panax ginseng. Its sterile fermentation liquid showed a significant inhibitory effect against Ilyonectria robusta, causing the rusty root rot of P. ginseng and P. quinquefolius. The antifungal protein was obtained after precipitation by 20% saturated ammonium sulfate, desalted by Sephadex G-25, weak anion exchange chromatography, and gel filtration chromatography. SDS-PAGE showed that the purified protein was approximately 29 KDa. The antifungal protein after desalting was not resistant to temperatures higher than 100 °C, resistant to acid conditions, and did not tolerate organic solvents and protease K. The amino acid sequence of purified antifungal protein had an identity of 76% to flagellin from Bacillus velezensis. The isoelectric point of the protein was 4.97 and its molecular mass was 27 KDa. Therefore, a specific primer G1 was designed based on the flagellin gene sequence, and a 770 bp gene sequence was cloned in NJ13 genomic DNA, which shared the same size of flagellin. There were ten base differences between the gene sequences of flagellin and the cloned gene, however, the amino acid sequence encoded by the cloned gene was identical to the flagellin. In conclusion, the antifungal protein produced by biocontrol agent NJ13 contained a flagellin protein.


Nematology ◽  
2014 ◽  
Vol 16 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Yong Seong Lee ◽  
Muhammad Anees ◽  
Yun Serk Park ◽  
Sun Bae Kim ◽  
Woo Jin Jung ◽  
...  

The root-knot nematodes, Meloidogyne spp., cause serious diseases in various plants and their chemical control may lead to environmental problems. Therefore, alternative control measures against the phytopathogenic nematodes are being sought. One of the potential targets against Meloidogyne spp. may be the chitinolysis and degradation of nematode eggs. Therefore, in the present study, a chitinolytic and nematicidal strain of Lysobacter capsici YS1215 was isolated from an agricultural field in Korea. The aim of this study was to purify chitinase secreted by L. capsici YS1215 and investigate its nematicidal role against Meloidogyne incognita. The chitinase secreted by L. capsici YS1215 was purified by protein precipitation with 80% ammonium sulphate, anion-exchange chromatography with DEAE-cellulose and gel-filtration chromatography with Sephadex G-100. By chitinase-active staining of the purified enzyme, a single band was obtained with an estimated molecular mass of 43.6 kDa. The optimal pH and optimal temperature for the highest chitinase activity were 6.0 and 40°C, respectively. The purified chitinase degraded the chitin layer of the eggshells and significantly reduced hatch of second-stage juveniles. The activity of chitinase secreted by L. capsici YS1215 was not affected by CoCl2, MnCl2, MgCl2, CuSO4, CaCl2 or EDTA. The purified enzyme could also hydrolyse swollen chitin, glycol chitin, glycol chitosan and chitin powder. Thus, the role of chitinase secreted by L. capsici YS1215 against Meloidogyne spp. may be useful for further development of a biocontrol agent.


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