Scorpion toxins from Centruroides noxius and Tityus serrulatus. Primary structures and sequence comparison by metric analysis

摘要: The complete primary structures of toxin II-14 from the Mexican scorpion Centruroides noxius Hoffmann and gamma Brazilian Tityus serrulatus Lutz Mello have been determined. Cleavage after Met-6 with CNBr produced 55-residue peptide 7-61, which maintained four disulphide bonds but was not toxic to mice at a dose 3 times lethal native gamma. Pairwise comparison by metric analysis segment 1-50 corresponding segments two other South American toxins, five North nine African toxins one Central Asian showed that three are intermediate between toxins. This result is consistent hypothesis continents were joined land connection in distant past.