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. 1973 Dec;116(3):1258–1266. doi: 10.1128/jb.116.3.1258-1266.1973

Multiplicity of Leucine Transport Systems in Escherichia coli K-12

Mohamad Rahmanian a,1, David R Claus a, Dale L Oxender a
PMCID: PMC246482  PMID: 4584809

Abstract

The major component of leucine uptake in Escherichia coli K-12 is a common system for l-leucine, l-isoleucine, and l-valine (LIV-I) with a Michaelis constant (Km) value of 0.2 μM (LIV-I system). The LIV-binding protein appears to be associated with this system. It now appears that the LIV-I transport system and LIV-binding protein also serve for the entry of l-alanine, l-threonine, and possibly l-serine. A minor component of l-leucine entry occurs by a leucine-specific system (L-system) for which a specific leucine-binding protein has been isolated. A mutant has been obtained that shows increased levels of the LIV-I transport activity and increased levels of both of the binding proteins. Another mutant has been isolated that shows only a major increase in the levels of the leucine-specific transport system and the leucine-specific binding protein. A third binding protein that binds all three branched-chain amino acids but binds isoleucine preferentially has been identified. The relationship of the binding proteins to each other and to transport activity is discussed. A second general transport system (LIV-II system) with a Km value of 2 μM and a relatively low Vmax can be observed in E. coli. The LIV-II system is not sensitive to osmotic shock treatment nor to growth of cells in the presence of leucine. This high Km system, which is specific for the branched-chain amino acids, can be observed in membrane vesicle preparations.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ames G. F., Lever J. Components of histidine transport: histidine-binding proteins and hisP protein. Proc Natl Acad Sci U S A. 1970 Aug;66(4):1096–1103. doi: 10.1073/pnas.66.4.1096. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. BRITTEN R. J., McCLURE F. T. The amino acid pool in Escherichia coli. Bacteriol Rev. 1962 Sep;26:292–335. doi: 10.1128/br.26.3.292-335.1962. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. COHEN G. N., RICKENBERG H. V. Concentration spécifique réversible des amino acides chez Escherichia coli. Ann Inst Pasteur (Paris) 1956 Nov;91(5):693–720. [PubMed] [Google Scholar]
  4. Furlong C. E., Cirakoglu C., Willis R. C., Santy P. A. A simple preparative polyacrylamide disc gel electrophoresis apparatus: purification of three branched-chain amino acid binding proteins from Escherichia coli. Anal Biochem. 1973 Jan;51(1):297–311. doi: 10.1016/0003-2697(73)90478-8. [DOI] [PubMed] [Google Scholar]
  5. Furlong C. E., Weiner J. H. Purification of a leucine-specific binding protein from Escherichia coli. Biochem Biophys Res Commun. 1970 Mar 27;38(6):1076–1083. doi: 10.1016/0006-291x(70)90349-9. [DOI] [PubMed] [Google Scholar]
  6. Krajewska-Grynkiewicz K., Walczak W., Klopotowski T. Mutants of Salmonella typhimurium able to utilize D-histidine as a source of L-histidine. J Bacteriol. 1971 Jan;105(1):28–37. doi: 10.1128/jb.105.1.28-37.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kuhn J., Somerville R. L. Mutant strains of Escherichia coli K12 that use D-amino acids. Proc Natl Acad Sci U S A. 1971 Oct;68(10):2484–2487. doi: 10.1073/pnas.68.10.2484. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Lombardi F. J., Kaback H. R. Mechanisms of active transport in isolated bacterial membrane vesicles. 8. The transport of amino acids by membranes prepared from Escherichia coli. J Biol Chem. 1972 Dec 25;247(24):7844–7857. [PubMed] [Google Scholar]
  9. Neal J. L. Analysis of Michaelis kinetics for two independent, saturable membrane transport functions. J Theor Biol. 1972 Apr;35(1):113–118. doi: 10.1016/0022-5193(72)90196-8. [DOI] [PubMed] [Google Scholar]
  10. 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]
  11. Penrose W. R., Nichoalds G. E., Piperno J. R., Oxender D. L. Purification and properties of a leucine-binding protein from Escherichia coli. J Biol Chem. 1968 Nov 25;243(22):5921–5928. [PubMed] [Google Scholar]
  12. Piperno J. R., Oxender D. L. Amino acid transport systems in Escherichia coli K-12. J Biol Chem. 1968 Nov 25;243(22):5914–5920. [PubMed] [Google Scholar]
  13. Rahmanian M., Oxender D. L. Derepressed leucine transport activity in Escherichia coli. J Supramol Struct. 1972;1(1):55–59. doi: 10.1002/jss.400010108. [DOI] [PubMed] [Google Scholar]
  14. Robbins J. C., Oxender D. L. Transport systems for alanine, serine, and glycine in Escherichia coli K-12. J Bacteriol. 1973 Oct;116(1):12–18. doi: 10.1128/jb.116.1.12-18.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Roth J. R. UGA nonsense mutations in Salmonella typhimurium. J Bacteriol. 1970 May;102(2):467–475. doi: 10.1128/jb.102.2.467-475.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Winter C. G., Christensen H. N. Contrasts in neutral amino acid transport by rabbit erythrocytes and reticulocytes. J Biol Chem. 1965 Sep;240(9):3594–3600. [PubMed] [Google Scholar]

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