Bacterialbinding protein-dependent transport systems,[1][2] are multicomponent systems typically composed of a periplasmic substrate-binding protein, one or two reciprocally homologous integral inner-membrane proteins and one or two peripheralmembrane ATP-binding proteins that couple energy to the active transport system. The integral inner-membrane proteins translocate the substrate across the membrane. It has been shown,[3][4] that most of these proteins contain a conserved region located about 80 to 100 residues from their C-terminal extremity. This region seems [5] to be located in a cytoplasmicloop between two transmembrane domains. Apart from the conserved region, the sequence of these proteins is quite divergent, and they have a variable number of transmembrane helices, however they can be classified into seven families which have been respectively termed: araH, cysTW, fecCD, hisMQ, livHM, malFG and oppBC.
^Saurin W, Kaster W, Dassa E (June 1994). "Bacterial binding protein-dependent permeases: characterization of distinctive signatures for functionally related integral cytoplasmic membrane proteins". Mol. Microbiol. 12 (6): 993–1004. doi:10.1111/j.1365-2958.1994.tb01087.x. PMID7934906. S2CID889103.
^Pearce SR, Mimmack ML, Gallagher MP, Gileadi U, Hyde SC, Higgins CF (January 1992). "Membrane topology of the integral membrane components, OppB and OppC, of the oligopeptide permease of Salmonella typhimurium". Mol. Microbiol. 6 (1): 47–57. doi:10.1111/j.1365-2958.1992.tb00836.x. PMID1738314. S2CID1660114.
