Simultaneous reconstitution of Escherichia coli membrane vesicles with D-lactate and D-amino acid dehydrogenases

Haldar, Kasturi ; Olsiewski, Paula J. ; Walsh, Christopher ; Kaczorowski, Gregory J. ; Bhaduri, Amar ; Ronald Kaback, H. (1982) Simultaneous reconstitution of Escherichia coli membrane vesicles with D-lactate and D-amino acid dehydrogenases Biochemistry, 21 (19). pp. 4590-4596. ISSN 0006-2960

Full text not available from this repository.

Official URL: http://pubs.acs.org/doi/abs/10.1021/bi00262a012

Related URL: http://dx.doi.org/10.1021/bi00262a012

Abstract

Purified preparations of D-amino acid dehydrogenase [Olsiewski, P.J., Kaczorowski, G. J., & Walsh, C. T. (1980) J. Biol. Chem. 225, 4487] and D-lactate dehydrogenase [Kohn, L.D., & Kaback, H.R. (1973) J. Biol. Chem. 248, 7012] bind independently to right-side-out and inverted Escherichia coli vesicles and to phosphatidylcholine liposomes without detectable competition. The reconstituted vesicles catalyze D-lactate- and D-alanine-dependent respiration (O2 uptake), proton translocation, and proton/lactose symport. The enzymes do not share common sites of association on either face of the E. coli membrane, and binding of both enzymes to the bilayer appears to be due to nonspecific affinity for the surface rather than specific binding to proteinaceous receptors. Each enzyme, however, appears to reduce a common proton translocating step in the membrane-bound respiratory chain, and substrate-derived electrons are transferred through a common rate-determining redox component that precedes the site of proton translocation. The results suggest that although binding is nonspecific, there is a common site for proton translocation in the membrane between the flavin-linked dehydrogenases and the cytochromes and that this site is accessible by distinct routes of electron transfer from primary dehydrogenases on either surface of the membrane.

Item Type:Article
Source:Copyright of this article belongs to American Chemical Society.
ID Code:26438
Deposited On:06 Dec 2010 12:32
Last Modified:16 May 2011 10:24

Repository Staff Only: item control page