title: Identification of a PutP proline permease gene homolog from Staphylococcus aureus by expression cloning of the high-affinity proline transport system in Escherichia coli.
abstract: The important food-borne pathogen Staphylococcus aureus is distinguished by its ability to grow at low water activity values. Previous work in our laboratory and by others has revealed that proline accumulation via transport is an important osmoregulatory strategy employed by this bacterium. Furthermore, proline uptake by this bacterium has been shown to be mediated by two distinct transport systems: a high-affinity system and a low-affinity system (J.-H. Bae, and K. J. Miller, Appl. Environ. Microbiol. 58:471-475, 1992; D. E. Townsend and B. J. Wilkinson, J. Bacteriol. 174:2702-2710, 1992). In the present study, we report the cloning of the high-affinity proline transport system of S. aureus by functional expression in an Escherichia coli host. The sequence of the staphylococcal proline permease gene was predicted to encode a protein of 497 amino acids which shares 49% identity with the PutP high-affinity proline permease of E. coli. Analysis of hydropathy also indicated a common overall structure for these proteins.
authors.affiliation: Department of Food Science, Pennsylvania State University, University Park 16802.
authors.forename: P A
authors.initials: PA
authors.lastname: Wengender
authors.forename: K J
authors.initials: KJ
authors.lastname: Miller
mesh_terms: D000595:Amino Acid Sequence; D026921:Amino Acid Transport Systems, Neutral; D001483:Base Sequence; D001692:Biological Transport; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids; D016415:Sequence Alignment; D013211:Staphylococcus aureus / Q000201:enzymology / Q000235:genetics*
chemical_list: D026921:Amino Acid Transport Systems, Neutral; D026901:Membrane Transport Proteins; C033082:proline transporter