Assignment of the three disulfide bonds of Selenocosmia huwena lectin-I from the venom of spider Selenocosmia huwena.

摘要: Abstract The positions of the disulfide bonds Selenocosmia huwena lectin-I (SHL-I) from venom Chinese bird spider S. have been determined. existence three in native SHL-I was proved by matrix-assisted laser desorption ionization time-of-flight mass spectroscopic analysis. To map bonds, proteolytically digested. resulting peptides were separated reverse phase high-performance liquid chromatography. Matrix-assisted analysis indicated presence one bond Cys7–Cys19. partially reduced using Tris-(2-carboxyethyl)-phosphine at pH 3.0 purified Four M Guanidine-HCl found to increase yields prominently. free thiols carboxamidomethlate iodoacetamide. specific location another Cys2–Cys14 comparing N-terminal sequencing and alkylated with that intact peptide. Finally, linkage could be assigned as Cys2–Cys14, Cys7–Cys19, Cys13–Cys26.