Symbol LctP InterPro IPR003804 Pfam structures | Pfam PF02652 TCDB 2.A.14 PDB RCSB PDB; PDBe; PDBj | |
The lactate permease (LctP) family (TC# 2.A.14) is a family of transport proteins belonging to the ion transporter (IT) superfamily. Proteins of the LctP family have been found in Gram-negative and Gram-positive bacteria as well as archaea.
Contents
Function
One member of the LctP family, from E. coli, is a lactate:H+ symporter. Two closely related paralogues have been found encoded within the E. coli genome (LctP and GlcA, TC# 2.A.14.1.1 and TC# 2.A.14.1.2, respectively), and one of these has been shown to be the glycolate uptake permease (GlcA). Both permeases transport the same acids (L- and D-lactate as well as glycolate), but their physiological substrates differ. The lactate permease transports both L- and D-lactate while the glycolate permease transports glycolate under physiological conditions. Regulatory effects determine the substrates transported in vivo. Characterized members of this family possess 15-18 transmembrane segments (TMSs) and are roughly 460-565 amino acyl residues in length.
General transport reaction
Transport reactions catalyzed by functionally characterized members of the LctP family include:
D- or L-lactate or glycolate (out) + H+ (out) → D- or L-lactate or glycolate (in) + H+ (in).