title: Domain structure and pore loops in the 2-hydroxycarboxylate transporter family.
abstract: The 2-hydroxycarboxylate transporter (2HCT) family is a family of bacterial secondary transporters for substrates like citrate, malate and lactate. The family is in class ST[3] of the MemGen classification system that groups membrane proteins in structural classes based on hydropathy profile analysis. The combination of computational analysis of the proteins in class ST[3] and available experimental data on members of the 2HCT family has yielded a detailed structural model of the transporters. The core of the model is formed by two homologous domains with opposite orientation in the membrane. Each domain consists of 5 trans membrane segments and contains a pore loop between the 4th and 5th segment. The two pore loops enter the membrane-embedded part from opposite sides of the membrane (trans pore loops) and are believed to form the translocation pathway in the 3D structure. A genome wide study of the cellular location of the C-terminus of all Escherichia coli membrane proteins [Daley et al., 2005. Science 308:1321-1323] showed that the C-termini of the 19 E. coli proteins in class ST[3] were correctly predicted by the structural model.
authors.affiliation: Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands. j.s.lolkema@rug.nl
authors.forename: Juke S
authors.initials: JS
authors.lastname: Lolkema
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D002264:Carboxylic Acids / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D026901:Membrane Transport Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D020543:Proteome
chemical_list: D001426:Bacterial Proteins; D002264:Carboxylic Acids; D026901:Membrane Transport Proteins; D020543:Proteome