Structure and Action of Heteronemertine Polypeptide Toxins
نویسنده
چکیده
The positions of the disulfide bonds in Cerebratulus lacteus toxin B-IV were investigated by hydrolysis of the unreduced protein with a variety of proteases. The resulting peptides were purified by gel filtration, ion exchange chromatography, and preparative paper electrophoresis and chromatography. Determination of the amino acid compositions of the cystine-containing peptides purified demonstrated the existence of disulfide bonds linking half-cystine residues 12 and 24,21 and 51, and 35 and 38. The fourth bond, involving half-cystines 10 and 47, was assigned by difference.
منابع مشابه
Structure and action of heteronemertine polypeptide toxins. Amino acid sequence of Cerebratulus lacteus toxin B-II and revised structure of toxin B-IV.
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