Members of this family include PorA, a channel-forming protein found mostly in Gram-positive bacteria [1].

1: Identification and characterization of the channel-forming protein in the cell wall of Corynebacterium amycolatum. Soltan Mohammadi N, Mafakheri S, Abdali N, Barcena-Uribarri I, Tauch A, Benz R; Biochim Biophys Acta. 2013;1828:2574-2582. PMID:23811360