کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2066254 1076982 2006 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Molecular cloning of the major lethal toxins from two kraits (Bungarus flaviceps and Bungarus candidus)
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیوشیمی، ژنتیک و زیست شناسی مولکولی (عمومی)
پیش نمایش صفحه اول مقاله
Molecular cloning of the major lethal toxins from two kraits (Bungarus flaviceps and Bungarus candidus)
چکیده انگلیسی
The major lethal toxins present in the venoms of the red-headed krait, Bungarus flaviceps, and the Malayan krait, Bungarus candidus, have both been purified. Each consists of two polypeptide chains, A and B, joined by a disulfide bond. In the present study, primary structures of these toxins were determined by Edman degradation and by nucleotide sequencing of the cDNA clones. Amino acid sequencing of the N-terminus and enzymatically digested peptides revealed that the A and B chains were highly homologous to those of β-bungarotoxins (β-Bgts) from Bungarus multicinctus, respectively. We isolated cDNA clones encoding the A and B chains from both B. flaviceps and B. candidus venom gland cDNA libraries using probes designed based on the cDNA sequence of β-Bgt from B. multicinctus. Two isoforms of the A chain and one isoform of the B chain were obtained from B. flaviceps, and one isoform of the A chain and two isoforms of the B chain were obtained from B. candidus. Both of the two A chains from B. flaviceps are made up of 119 amino acids and comprise 15 cysteine residues, while the A chains of β-Bgt from other Bungarus species including B. candidus comprise 13 cysteine residues. The B chains from both species are composed of 59 amino acid residues and comprise seven cysteines. In conclusion, the lethal toxin from B. flaviceps is considered to be a novel isoform of β-Bgt, which has a different pattern of cysteine residues from known β-Bgts.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Toxicon - Volume 47, Issue 4, 15 March 2006, Pages 416-424
نویسندگان
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