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. 1989 Sep;171(9):5148–5154. doi: 10.1128/jb.171.9.5148-5154.1989

Binding-protein-dependent alanine transport in Rhodobacter sphaeroides is regulated by the internal pH.

T Abee 1, F J van der Wal 1, K J Hellingwerf 1, W N Konings 1
PMCID: PMC210329  PMID: 2788647

Abstract

The properties of an L-alanine uptake system in Rhodobacter sphaeroides were studied and compared with those of H+/lactose symport in R. sphaeroides 4P1, a strain in which the lactose carrier of Escherichia coli has been cloned and functionally expressed (F. E. Nano, Ph.D. thesis, University of Illinois, Urbana, 1984). Previous studies indicated that both transport systems were active only when electron transfer took place in the respiratory or cyclic electron transfer chain, while uptake of L-alanine also required the presence of K+ (M. G. L. Elferink, Ph.D. thesis, University of Groningen, Groningen, The Netherlands, 1986). The results presented in this paper offer an explanation for these findings. Transport of the nonmetabolizable L-alanine analog 2-alpha-aminoisobutyric acid (AIB) is mediated by a shock-sensitive transport system. The apparently unidirectional uptake of AIB results in accumulation levels which exceed 7 x 10(3). The finding of L-alanine-binding activity in the concentrated crude shock fluid indicates that L-alanine is taken up by a binding-protein-dependent transport system. Transport of the nonmetabolizable lactose analog methyl-beta-D-thiogalactopyranoside (TMG) by the lactose carrier under anaerobic conditions in the dark was observed in cells and membrane vesicles. This indicates that the H+/lactose symport system is active without electron transfer. Uptake of AIB, but not that of TMG, is inhibited by vanadate with a 50% inhibitory concentration of 50 microM, which suggests a role of a phosphorylated intermediate in AIB transport. Uptake of TMG and AIB is regulated by the internal pH. The initial rates of uptake increased with the internal pH, and and pKa values of 7.2 for TMG and 7.8 for AIB. At an internal pH of 7, no AIB uptake occurred, and the rate of TMG uptake was only 30% of the rate at an internal pH of 8. In a previous study, we found that K+ plays an essential role in regulating the internal pH (T. Abee, K. J. Hellingwerf, and W. N. Konings, J. Bacteriol. 170:5647-5653, 1988). The dependence of solute transport in R. sphaeroides on both K+ and activity of an electron transfer chain can be explained by an effect of the internal pH, which subsequently influences the activities of the lactose-and binding-protein-dependent L-alanine transport system.

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Selected References

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  1. Abee T., Hellingwerf K. J., Konings W. N. Effects of potassium ions on proton motive force in Rhodobacter sphaeroides. J Bacteriol. 1988 Dec;170(12):5647–5653. doi: 10.1128/jb.170.12.5647-5653.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Ames G. F. Bacterial periplasmic transport systems: structure, mechanism, and evolution. Annu Rev Biochem. 1986;55:397–425. doi: 10.1146/annurev.bi.55.070186.002145. [DOI] [PubMed] [Google Scholar]
  3. Ames G. F. Structure and mechanism of bacterial periplasmic transport systems. J Bioenerg Biomembr. 1988 Feb;20(1):1–18. doi: 10.1007/BF00762135. [DOI] [PubMed] [Google Scholar]
  4. Bakker E. P., Borchard A., Michels M., Altendorf K., Siebers A. High-affinity potassium uptake system in Bacillus acidocaldarius showing immunological cross-reactivity with the Kdp system from Escherichia coli. J Bacteriol. 1987 Sep;169(9):4342–4348. doi: 10.1128/jb.169.9.4342-4348.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cairney J., Higgins C. F., Booth I. R. Proline uptake through the major transport system of Salmonella typhimurium is coupled to sodium ions. J Bacteriol. 1984 Oct;160(1):22–27. doi: 10.1128/jb.160.1.22-27.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Dean D. A., Fikes J. D., Gehring K., Bassford P. J., Jr, Nikaido H. Active transport of maltose in membrane vesicles obtained from Escherichia coli cells producing tethered maltose-binding protein. J Bacteriol. 1989 Jan;171(1):503–510. doi: 10.1128/jb.171.1.503-510.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Elferink M. G., Hellingwerf K. J., Konings W. N. The role of the proton motive force and electron flow in solute transport in Escherichia coli. Eur J Biochem. 1985 Nov 15;153(1):161–165. doi: 10.1111/j.1432-1033.1985.tb09282.x. [DOI] [PubMed] [Google Scholar]
  8. Elferink M. G., Hellingwerf K. J., Nano F. E., Kaplan S., Konings W. N. The lactose carrier of Escherichia coli functionally incorporated in Rhodopseudomonas sphaeroides obeys the regulatory conditions of the phototrophic bacterium. FEBS Lett. 1983 Nov 28;164(1):185–190. doi: 10.1016/0014-5793(83)80046-5. [DOI] [PubMed] [Google Scholar]
  9. Erecińska M., Deutsch C. J., Davis J. S. Energy coupling to K+ transport in Paracoccus denitrificans. J Biol Chem. 1981 Jan 10;256(1):278–284. [PubMed] [Google Scholar]
  10. Hobson A. C., Weatherwax R., Ames G. F. ATP-binding sites in the membrane components of histidine permease, a periplasmic transport system. Proc Natl Acad Sci U S A. 1984 Dec;81(23):7333–7337. doi: 10.1073/pnas.81.23.7333. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hong J. S., Hunt A. G., Masters P. S., Lieberman M. A. Requirements of acetyl phosphate for the binding protein-dependent transport systems in Escherichia coli. Proc Natl Acad Sci U S A. 1979 Mar;76(3):1213–1217. doi: 10.1073/pnas.76.3.1213. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. 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]
  13. Neu H. C., Heppel L. A. The release of enzymes from Escherichia coli by osmotic shock and during the formation of spheroplasts. J Biol Chem. 1965 Sep;240(9):3685–3692. [PubMed] [Google Scholar]
  14. Ohnishi K., Kiritani K. Purification and properties of two binding proteins for branched-chain amino acids in Salmonella typhimurium. J Biochem. 1983 Aug;94(2):433–441. doi: 10.1093/oxfordjournals.jbchem.a134373. [DOI] [PubMed] [Google Scholar]
  15. Page M. G., Rosenbusch J. P., Yamato I. The effects of pH on proton sugar symport activity of the lactose permease purified from Escherichia coli. J Biol Chem. 1988 Nov 5;263(31):15897–15905. [PubMed] [Google Scholar]
  16. Page M. G. The role of protons in the mechanism of galactoside transport via the lactose permease of Escherichia coli. Biochim Biophys Acta. 1987 Feb 12;897(1):112–126. doi: 10.1016/0005-2736(87)90319-1. [DOI] [PubMed] [Google Scholar]
  17. Poolman B., Hellingwerf K. J., Konings W. N. Regulation of the glutamate-glutamine transport system by intracellular pH in Streptococcus lactis. J Bacteriol. 1987 May;169(5):2272–2276. doi: 10.1128/jb.169.5.2272-2276.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Richarme G., Kepes A. Study of binding protein-ligand interaction by ammonium sulfate-assisted adsorption on cellulose esters filters. Biochim Biophys Acta. 1983 Jan 12;742(1):16–24. doi: 10.1016/0167-4838(83)90353-9. [DOI] [PubMed] [Google Scholar]
  19. 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]

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