Syphilis is a chronic communicable disease that seriously affects human health and is caused by infection of Trepone-ma pallidum.Outer membrane protein(Omp)of Treponema pallidum is a class of proteins with key functions.Omp plays a very important role in the immunogenicity,adhesion to host cells and transport nutrients of Treponema pallidum.This article reviews the structure,function and other characteristics of the m...