Separation and structure-function studies of Taiwan cobra cardiotoxins.
Six cardiotoxins (CTXs) and one cardiotoxin-like basic protein (CLBP) from Naja naja atra (Taiwan cobra) venom were separated by a SP-Sephadex C-25 column. CTXn and CTXI were well separated by eluting with ammonium acetate buffer, and the separation of CLBP from CTXIV and CTXV mixtures was achieved using sodium phosphate buffer. These findings suggest a differential interaction of CTXs with the chromatographic matrix using different buffer systems. Chemical modification studies on cationic residues of CTXI suggested that there was no single lysine or arginine residue exclusively responsible for its biological activity. Moreover, it was found that the cytotoxicity and hemolytic sites of CTXI could be dissociated by chemical modifications. It suggests the potentiality for preparing toxin derivatives in which a specific activity is retained.
Lin
Shinne-Ren
SR
School of Chemistry, Kaohsiung Medical University, Taiwan, ROC. shreli@cc.kmu.edu.tw
Chang
Long-Sen
LS
Chang
Kee-Lung
KL
D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004179:Cobra Cardiotoxin Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity; D004546:Elapid Venoms / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity; D017815:Elapidae; D004912:Erythrocytes / Q000187:drug effects / Q000473:pathology; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D013624:Taiwan
D004179:Cobra Cardiotoxin Proteins; D004546:Elapid Venoms; C037375:cobra cytotoxin I; D001120:Arginine