Amino acid sequence of an egg-lysin protein from abalone spermatozoa that solubilizes the vitelline layer.

摘要: Spermatozoa of the California red abalone (Haliotis rufescens; Phylum Mollusca, order Archeogastropoda) possess an acrosomal protein that dissolves egg vitelline layer during fertilization. Evidence strongly suggests dissolution mechanism is a stoichiometric, nonenzymatic process depends on hydrophobic nature sperm which should therefore be termed egg-lysin. Here we report complete amino acid sequence this unique protein. Peptides obtained by cyanogen bromide cleavage and trypsin V8 protease digestions were isolated subjected to automated Edman degradation. Seven CNBr fragments accounted for intact lysin proteolytically derived peptides used establish these fragments. The composed 134 acids contains 36 charged acids. majority occur at distances 2 or 3 residues from each other. A stretch 41 10 positively no negatively residue. Model building experiments demonstrated may in alpha-helical regions would occupy one-half circumference such helices. other half display predominantly residues. This arrangement account biological properties lysin.