HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nakamura, T. Articles by Rosen, B. P. Search for Related Content PubMed PubMed Citation Articles by Nakamura, T. Articles by Rosen, B. P. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 261, Issue 2, 678-683, 01, 1986

Cation/proton antiport systems in Escherichia coli. Solubilization and reconstitution of delta pH-driven sodium/proton and calcium/proton antiporters

T Nakamura, C Hsu and BP Rosen

Uptake of 22Na+ and 45Ca2+ into everted membrane vesicles from Escherichia coli was measured with imposed transmembrane pH gradients, acid interior, as driving force. Vesicles loaded with 0.5 M KCl were diluted into 0.5 M choline chloride to create a potassium gradient. Addition of nigericin to produce K+/H+ exchange resulted in formation of a pH gradient. This imposed gradient was capable of driving 45Ca2+ accumulation. In another method vesicles loaded with 0.5 M NH4Cl were diluted into 0.5 M choline chloride, creating an ammonium diffusion potential. A gradient of H+ was produced by passive efflux of NH3. With an ammonium gradient as driving force, everted vesicles accumulated both 45Ca2+ and 22Na+. The data suggest that 22Na+ uptake was via the sodium/proton antiporter and 45Ca2+ via the calcium/proton antiporter. Uptake of both cations required alkaline pHout. A minimum pH gradient of 0.9 unit was needed for transport of either ion, suggesting gating of the antiporters. Octyl glucoside extracts of inner membrane were reconstituted with E. coli phospholipids in 0.5 M NH4Cl. NH4+-loaded proteoliposomes accumulated both 22Na+ and 45Ca2+, demonstrating that the sodium/proton and calcium/proton antiporters could be solubilized and reconstituted in a functional form.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				N. Nakamura, S. Tanaka, Y. Teko, K. Mitsui, and H. Kanazawa Four Na+/H+ Exchanger Isoforms Are Distributed to Golgi and Post-Golgi Compartments and Are Involved in Organelle pH Regulation J. Biol. Chem., January 14, 2005; 280(2): 1561 - 1572. [Abstract] [Full Text] [PDF]

				T. Nakamura, Y. Fujisaki, H. Enomoto, Y. Nakayama, T. Takabe, N. Yamaguchi, and N. Uozumi Residue Aspartate-147 from the Third Transmembrane Region of Na+/H+ Antiporter NhaB of Vibrio alginolyticus Plays a Role in Its Activity J. Bacteriol., October 1, 2001; 183(19): 5762 - 5767. [Abstract] [Full Text] [PDF]

				M. L. Nelson and S. B. Levy Reversal of Tetracycline Resistance Mediated by Different Bacterial Tetracycline Resistance Determinants by an Inhibitor of the Tet(B) Antiport Protein Antimicrob. Agents Chemother., July 1, 1999; 43(7): 1719 - 1724. [Abstract] [Full Text]

				A. A. Guffanti, J. Cheng, and T. A. Krulwich Electrogenic Antiport Activities of the Gram-positive Tet Proteins Include a Na+(K+)/K+ Mode That Mediates Net K+ Uptake J. Biol. Chem., October 9, 1998; 273(41): 26447 - 26454. [Abstract] [Full Text] [PDF]

				K. Venema, F. J. Quintero, J. M. Pardo, and J. P. Donaire The Arabidopsis Na+/H+ Exchanger AtNHX1 Catalyzes Low Affinity Na+ and K+ Transport in Reconstituted Liposomes J. Biol. Chem., January 18, 2002; 277(4): 2413 - 2418. [Abstract] [Full Text] [PDF]