This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Schaffitzel, C.
Right arrow Articles by Pos, K. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schaffitzel, C.
Right arrow Articles by Pos, K. M.

 Previous Article  |  Next Article 

J Bacteriol, May 1998, p. 2689-2693, Vol. 180, No. 10
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Identification of an Na+-Dependent Malonate Transporter of Malonomonas rubra and Its Dependence on Two Separate Genes

Christiane Schaffitzel,dagger Michael Berg, Peter Dimroth, and Klaas M. Pos*

Mikrobiologisches Institut, Eidgenössische Technische Hochschule, Zürich, Switzerland

Received 3 February 1998/Accepted 20 March 1998

Two membrane proteins encoded by the malonate fermentation gene cluster of Malonomonas rubra, MadL and MadM, have been synthesized in Escherichia coli. MadL and MadM were shown to function together as a malonate transport system, whereas each protein alone was unable to catalyze malonate transport. Malonate transport by MadLM is Na+ dependent, and imposition of a Delta pNa+ markedly enhanced the rate of malonate uptake. The kinetics of malonate uptake into E. coli BL21(DE3) cells synthesizing MadLM at different pH values indicated that Hmalonate- is the transported malonate species. The stimulation of malonate uptake by Na+ ions showed Michaelis-Menten kinetics, and a Km for Na+ of 1.2 mM was determined. These results suggest that MadLM is an electroneutral Na+/Hmalonate- symporter and that it is dependent on two separate genes.

* Corresponding author. Mailing address: Mikrobiologisches Institut, Eidgenössische Technische Hochschule, ETH-Zentrum, Schmelzbergstrasse 7, CH-8092 Zürich, Switzerland. Phone: 41-1-632 5523. Fax: 41-1-632 1148. E-mail: pos{at}micro.biol.ethz.ch.

dagger Present address: Biochemisches Institut, Universität Zürich, 8057 Zürich, Switzerland.

J Bacteriol, May 1998, p. 2689-2693, Vol. 180, No. 10
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Oberhardt, M. A., Puchalka, J., Fryer, K. E., Martins dos Santos, V. A. P., Papin, J. A. (2008). Genome-Scale Metabolic Network Analysis of the Opportunistic Pathogen Pseudomonas aeruginosa PAO1. J. Bacteriol. 190: 2790-2803 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»