Applied and Environmental Microbiology, July 2005, p. 3389-3398, Vol. 71, No. 7
0099-2240/05/$08.00+0 doi:10.1128/AEM.71.7.3389-3398.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
OusB, a Broad-Specificity ABC-Type Transporter from Erwinia chrysanthemi, Mediates Uptake of Glycine Betaine and Choline with a High Affinity
Gwénaëlle Choquet,
Nathalie Jehan,
Christine Pissavin,
Carlos Blanco, and
Mohamed Jebbar*
Université de Rennes I, UMR-CNRS 6026, Département Osmorégulation chez les Bactéries, Campus de Beaulieu, Ave. du Général Leclerc, 35042 Rennes, France
Received 10 November 2004/
Accepted 4 January 2005
The ability of Erwinia chrysanthemi to cope with environments of elevated osmolality is due in part to the transport and accumulation of osmoprotectants. In this study we have identified a high-affinity glycine betaine and choline transport system in E. chrysanthemi. By using a pool of Tn5-B21 ousA mutants, we isolated a mutant that could grow in the presence of a toxic analogue of glycine betaine (benzyl-glycine betaine) at high osmolalities. This mutant was impaired in its ability to transport all effective osmoprotectants in E. chrysanthemi. The DNA sequence of the regions flanking the transposon insertion site revealed three chromosomal genes (ousVWX) that encode components of an ABC-type transporter (OusB): OusV (ATPase), OusW (permease), and OusX (periplasmic binding protein). The OusB components showed a significant degree of sequence identity to components of ProU from Salmonella enterica serovar Typhimurium and Escherichia coli. OusB was found to restore the uptake of glycine betaine and choline through functional complementation of an E. coli mutant defective in both ProU and ProP osmoprotectant uptake systems. Competition experiments demonstrated that choline, dimethylsulfoniacetate, dimethylsulfoniopropionate, and ectoine were effective competitors for OusB-mediated betaine transport but that carnitine, pipecolate, and proline were not effective. In addition, the analysis of single and double mutants showed that OusA and OusB were the only osmoprotectant transporters operating in E. chrysanthemi.
* Corresponding author. Mailing address: Université de Rennes I, UMR-CNRS 6026, Département Osmorégulation chez les Bactéries, Campus de Beaulieu, Av. du Général Leclerc, 35042 Rennes, France. Phone: (33) 2-23-23-68-52. Fax: (33) 2-23-23-67-75. E-mail: mohamed.jebbar{at}univ-rennes1.fr.
Applied and Environmental Microbiology, July 2005, p. 3389-3398, Vol. 71, No. 7
0099-2240/05/$08.00+0 doi:10.1128/AEM.71.7.3389-3398.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Chen, C., Beattie, G. A.
(2008). Pseudomonas syringae BetT Is a Low-Affinity Choline Transporter That Is Responsible for Superior Osmoprotection by Choline over Glycine Betaine. J. Bacteriol.
190: 2717-2725
[Abstract]
[Full Text]
-
Chen, C., Beattie, G. A.
(2007). Characterization of the Osmoprotectant Transporter OpuC from Pseudomonas syringae and Demonstration that Cystathionine-{beta}-Synthase Domains Are Required for Its Osmoregulatory Function. J. Bacteriol.
189: 6901-6912
[Abstract]
[Full Text]
-
Alloing, G., Travers, I., Sagot, B., Le Rudulier, D., Dupont, L.
(2006). Proline Betaine Uptake in Sinorhizobium meliloti: Characterization of Prb, an Opp-Like ABC Transporter Regulated by both Proline Betaine and Salinity Stress.. J. Bacteriol.
188: 6308-6317
[Abstract]
[Full Text]
-
Diab, F., Bernard, T., Bazire, A., Haras, D., Blanco, C., Jebbar, M.
(2006). Succinate-mediated catabolite repression control on the production of glycine betaine catabolic enzymes in Pseudomonas aeruginosa PAO1 under low and elevated salinities.. Microbiology
152: 1395-1406
[Abstract]
[Full Text]
-
Venkatesh, B., Babujee, L., Liu, H., Hedley, P., Fujikawa, T., Birch, P., Toth, I., Tsuyumu, S.
(2006). The Erwinia chrysanthemi 3937 PhoQ Sensor Kinase Regulates Several Virulence Determinants.. J. Bacteriol.
188: 3088-3098
[Abstract]
[Full Text]
Copyright © 2005 by the American Society for Microbiology. All rights reserved.