Structural determination and characterization of the envelope proteins of shrimp white spot syndrome virus (WSSV)

Abstract

White spot syndrome virus is a virulent pathogen known to infect penaeid shrimp and other crustaceans. Here we report the localization and crystal structure of two major envelope proteins VP26 and VP28 at 2.2 and 2.0?? respectively. Their structures are being reported for the first time for WSSV. Both proteins adopt I?-barrels architecture with a protruding region. Our localization study suggests that VP26 and VP28 are on the outer surface of the virus and resembled as a spike-like structure on the WSSV envelope, this is the first convincing observation for VP26. Based on our present studies combined with previous findings from other groups, we propose that VP26 and VP28 may anchor on the viral envelope membrane via their predicted N-terminal transmembrane regions, while leaving the core I?-barrel to protrude outside the envelope to interact with the host receptor or to fuse with the host cell membrane for effective viral infection.