Abstract
Reaction centers of the phototrophic bacterium Rhodopseudomonas palustris were introduced as proton motive force-generating systems in membrane vesicles of two anaerobic bacteria. Liposomes containing reaction center-light-harvesting complex I pigment protein complexes were fused with membrane vesicles of Streptococcus cremoris or Clostridium acetobutylicum by freeze-thawing and sonication. Illumination of these fused membranes resulted in the generation of a proton motive force of approximately -110 mV. The magnitude of the proton motive force in these membranes could be varied by changing the light intensity. As a result of this proton motive force, amino acid transport into the fused membranes could be observed. The initial rate of leucine transport by membrane vesicles of S. cremoris increased exponentially with the proton motive force. An H+/leucine stoichiometry of 0.8 was determined from the steady-state level of leucine accumulation and the proton motive force, and this stoichiometry was found to be independent of the magnitude of the proton motive force. These results indicate that the introduction of bacterial reaction centers in membrane vesicles by the fusion procedure yields very attractive model systems for the study of proton motive force-consuming processes in membrane vesicles of (strict) anaerobic bacteria.
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Selected References
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- Driessen A. J., Hellingwerf K. J., Konings W. N. Mechanism of energy coupling to entry and exit of neutral and branched chain amino acids in membrane vesicles of Streptococcus cremoris. J Biol Chem. 1987 Sep 15;262(26):12438–12443. [PubMed] [Google Scholar]
- Driessen A. J., Hellingwerf K. J., Konings W. N. Membrane systems in which foreign proton pumps are incorporated. Microbiol Sci. 1987 Jun;4(6):173–180. [PubMed] [Google Scholar]
- Driessen A. J., Kodde J., de Jong S., Konings W. N. Neutral amino acid transport by membrane vesicles of Streptococcus cremoris is subject to regulation by internal pH. J Bacteriol. 1987 Jun;169(6):2748–2754. doi: 10.1128/jb.169.6.2748-2754.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Driessen A. J., Konings W. N. Calcium transport in membrane vesicles of Streptococcus cremoris. Eur J Biochem. 1986 Aug 15;159(1):149–155. doi: 10.1111/j.1432-1033.1986.tb09845.x. [DOI] [PubMed] [Google Scholar]
- Driessen A. J., Ubbink-Kok T., Konings W. N. Amino acid transport by membrane vesicles of an obligate anaerobic bacterium, Clostridium acetobutylicum. J Bacteriol. 1988 Feb;170(2):817–820. doi: 10.1128/jb.170.2.817-820.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Driessen A. J., de Jong S., Konings W. N. Transport of branched-chain amino acids in membrane vesicles of Streptococcus cremoris. J Bacteriol. 1987 Nov;169(11):5193–5200. doi: 10.1128/jb.169.11.5193-5200.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Driessen A. J., de Vrij W., Konings W. N. Functional incorporation of beef-heart cytochrome c oxidase into membranes of Streptococcus cremoris. Eur J Biochem. 1986 Feb 3;154(3):617–624. doi: 10.1111/j.1432-1033.1986.tb09443.x. [DOI] [PubMed] [Google Scholar]
- Driessen A. J., de Vrij W., Konings W. N. Incorporation of beef heart cytochrome c oxidase as a proton-motive force-generating mechanism in bacterial membrane vesicles. Proc Natl Acad Sci U S A. 1985 Nov;82(22):7555–7559. doi: 10.1073/pnas.82.22.7555. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Otto R., Lageveen R. G., Veldkamp H., Konings W. N. Lactate efflux-induced electrical potential in membrane vesicles of Streptococcus cremoris. J Bacteriol. 1982 Feb;149(2):733–738. doi: 10.1128/jb.149.2.733-738.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SISTROM W. R. A requirement for sodium in the growth of Rhodopseudomonas spheroides. J Gen Microbiol. 1960 Jun;22:778–785. doi: 10.1099/00221287-22-3-778. [DOI] [PubMed] [Google Scholar]
- Shinbo T., Kamo N., Kurihara K., Kobatake Y. A PVC-based electrode sensitive to DDA+ as a device for monitoring the membrane potential in biological systems. Arch Biochem Biophys. 1978 Apr 30;187(2):414–422. doi: 10.1016/0003-9861(78)90052-8. [DOI] [PubMed] [Google Scholar]