This family of proteins is found in bacteria. Proteins in this family are typically between 200 and 228 amino acids in length. T_hemolysin is a pore-forming toxin of bacteria, able to lyse erythrocytes from a number of mammalian species.

1: Cloning and characterization of a novel haemolysin in Vibrio cholerae O1 that does not directly contribute to the virulence of the organism. Fallarino A, Attridge SR, Manning PA, Focareta T; Microbiology. 2002;148:2181-2189. PMID:12101305