This family of membrane proteins consists of Type II secretion system protein M sequences from several Gram-negative (diderm) bacteria. The precise function of these proteins is unknown, though in Vibrio cholerae, the T2SM (EpsM) protein interacts with the T2SL (EpsL) protein, and also forms homodimers.
Jiyao W et al.(2023). "The conserved domain database in 2023.",