title: Multidrug resistance in lactic acid bacteria: molecular mechanisms and clinical relevance.
abstract: The active extrusion of cytotoxic compounds from the cell by multidrug transporters is one of the major causes of failure of chemotherapeutic treatment of tumor cells and of infections by pathogenic microorganisms. The secondary multidrug transporter LmrP and the ATP-binding cassette (ABC) type multidrug transporter LmrA in Lactococcus lactis are representatives of the two major classes of multidrug transporters found in pro- and eukaryotic organisms. Therefore, knowledge of the molecular properties of LmrP and LmrA will have a wide significance for multidrug transporters in all living cells, and may enable the development of specific inhibitors and of new drugs which circumvent the action of multidrug transporters. Interestingly, LmrP and LmrA are transport proteins with very different protein structures, which use different mechanisms of energy coupling to transport drugs out of the cell. Surprisingly, both proteins have overlapping specificities for drugs, are inhibited by the same set of modulators, and transport drugs via a similar transport mechanism. The structure-function relationships that dictate drug recognition and transport by LmrP and LmrA will represent an intriguing new area of research.
authors.affiliation: Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Haren, The Netherlands. h.w.van.veen@biol.rug.nl
authors.forename: H W
authors.initials: HW
authors.lastname: van Veen
authors.forename: A
authors.initials: A
authors.lastname: Margolles
authors.forename: M
authors.initials: M
authors.lastname: Putman
authors.forename: K
authors.initials: K
authors.lastname: Sakamoto
authors.forename: W N
authors.initials: WN
authors.lastname: Konings
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000235:genetics*; D019344:Lactic Acid / Q000378:metabolism*; D013294:Lactococcus lactis / Q000187:drug effects / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D002352:Carrier Proteins; D019344:Lactic Acid; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C101824:LmrA protein, Lactococcus lactis; C096807:LmrP protein, Lactococcus lactis