1LYN

CRYSTAL STRUCTURE AND SUBUNIT DYNAMICS OF THE LYSIN DIMER: EGG ENVELOPES DISSOCIATE DIMERS, THE MONOMER IS THE ACTIVE SPECIES

Summary for 1LYN

• Entry DOI: 10.2210/pdb1lyn/pdb
• Descriptor: SPERM LYSIN (1 entity in total)
• Functional Keywords: fertilization protein
• Biological source: Haliotis rufescens (California red abalone)
• Total number of polymer chains: 2
• Total formula weight: 32590.44

Authors

Shaw, A.,Vacquier, V.D.,Stout, C.D. (deposition date: 1995-03-03, release date: 1995-06-03, Last modification date: 2024-02-14)

Primary citation

Shaw, A.,Fortes, P.A.,Stout, C.D.,Vacquier, V.D.
Crystal structure and subunit dynamics of the abalone sperm lysin dimer: egg envelopes dissociate dimers, the monomer is the active species.
J.Cell Biol., 130:1117-1125, 1995

PubMed Abstract: Lysin is a 16-kD acrosomal protein used by abalone spermatozoa to create a hole in the egg vitelline envelope (VE) by a nonenzymatic mechanism. The crystal structure of the lysin monomer is known at 1.9 A resolution. The surface of the molecule reveals two tracks of basic residues running the length of one surface of the molecule and a patch of solvent-exposed hydrophobic residues on the opposite surface. Here we report that lysin dimerizes via interaction of the hydrophobic patches of monomers. Triton X-100 dissociates the dimer. The crystal structure of the dimer is described at 2.75 A resolution. Fluorescence energy transfer experiments show that the dimer has an approximate KD of 1 microM and that monomers exchange rapidly between dimers. Addition of isolated egg VE dissociates dimers, implicating monomers as the active species in the dissolution reaction. This work represents the first step in the elucidation of the mechanism by which lysin enables abalone spermatozoa to create a hole in the egg envelope during fertilization.

PubMed: 7657696
DOI: 10.1083/jcb.130.5.1117

Experimental method

X-RAY DIFFRACTION (2.75 Å)