{"title":"The amino acid sequence of toxin D isolated from the venom of indian cobra (Naja naja)","authors":"Mitsuhiro Ohta , Toyosaku Sasaki , Kyozo Hayashi","doi":"10.1016/0005-2795(81)90125-2","DOIUrl":null,"url":null,"abstract":"<div><p>A neurotoxin, designated toxin D, was isolated from the venom of <em>Naja naja</em> by gel-filtration on Sephadex G-50 followed by CM-cellulose chromatography. The amino acid sequence of toxin D was determined by analyzing tryptic and chymotryptic peptides of the reduced and <span><math><mtext>S-</mtext><mtext>carboxymethyl</mtext></math></span> derivative. The venom contains at least four long (toxins A, B, C and D) and two short neurotoxins (toxins I and II) that account for about 16% of the lyophilized crude venom by weight. Toxin D consists of 71 amino acid residues in a single peptide chain cross-linked by five intramolecular disulfide bridges. The lethal toxicity of toxin D is found to be about half those of toxins A, B and C in the venom. Analysis of the amino acid sequence reveals that toxin D differs from toxin A in having -Arg-31, -Glu-35 and -Lys-49 in place of -Ser-31, -Lys-35 and -Arg-49 residues.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 123-128"},"PeriodicalIF":0.0000,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90125-2","citationCount":"8","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochimica et Biophysica Acta (BBA) - Protein Structure","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0005279581901252","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 8
Abstract
A neurotoxin, designated toxin D, was isolated from the venom of Naja naja by gel-filtration on Sephadex G-50 followed by CM-cellulose chromatography. The amino acid sequence of toxin D was determined by analyzing tryptic and chymotryptic peptides of the reduced and derivative. The venom contains at least four long (toxins A, B, C and D) and two short neurotoxins (toxins I and II) that account for about 16% of the lyophilized crude venom by weight. Toxin D consists of 71 amino acid residues in a single peptide chain cross-linked by five intramolecular disulfide bridges. The lethal toxicity of toxin D is found to be about half those of toxins A, B and C in the venom. Analysis of the amino acid sequence reveals that toxin D differs from toxin A in having -Arg-31, -Glu-35 and -Lys-49 in place of -Ser-31, -Lys-35 and -Arg-49 residues.