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. 1996 Jul;64(7):2765–2773. doi: 10.1128/iai.64.7.2765-2773.1996

Acidification of phagosomes containing Salmonella typhimurium in murine macrophages.

M Rathman 1, M D Sjaastad 1, S Falkow 1
PMCID: PMC174137  PMID: 8698506

Abstract

Salmonella species are facultative intracellular pathogens. Following entry into mammalian host cells, they reside in membrane-bound vacuoles, resist killing, and replicate. In this work, we investigated the importance of phagosomal pH in the ability of Salmonella typhimurium to survive and replicate within macrophages. Intraphagosomal pH was measured in situ by recording the fluorescence intensity of a pH-sensitive probe, DM-NERF dextran. The majority of vacuoles containing S. typhimurium (live, heat killed, or formalin fixed) acidified from pH > or = 6.0 to between pH 4.0 and 5.0 within 60 min after formation. In contrast, Mycobacterium avium-containing vacuoles failed to acidify even at later time points. Acidification of S. typhimurium-containing vacuoles was completely blocked by treatment of host cells with bafilomycin A, a specific inhibitor of vacuolar proton-ATPases. Bafilomycin inhibition of vacuolar acidification from the onset of infection significantly decreased the survival of S. typhimurium in macrophages. Furthermore, bafilomycin treatment at 2, 4, 8, or even 12 h postinfection decreased the percentage of recoverable bacteria by up to 20-fold. Loss of bacterial viability was seen with several other reagents which, like bafilomycin, raise the pH of phagosomal compartments but are not directly lethal to the bacteria or host cells. Thus, we conclude that Salmonella-containing phagosomes acidify soon after formation and hypothesize that an acidic environment is necessary for survival and replication of the bacteria within the macrophage.

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Selected References

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  1. Abshire K. Z., Neidhardt F. C. Analysis of proteins synthesized by Salmonella typhimurium during growth within a host macrophage. J Bacteriol. 1993 Jun;175(12):3734–3743. doi: 10.1128/jb.175.12.3734-3743.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Alpuche Aranda C. M., Swanson J. A., Loomis W. P., Miller S. I. Salmonella typhimurium activates virulence gene transcription within acidified macrophage phagosomes. Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10079–10083. doi: 10.1073/pnas.89.21.10079. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Alpuche-Aranda C. M., Racoosin E. L., Swanson J. A., Miller S. I. Salmonella stimulate macrophage macropinocytosis and persist within spacious phagosomes. J Exp Med. 1994 Feb 1;179(2):601–608. doi: 10.1084/jem.179.2.601. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Antoine J. C., Prina E., Jouanne C., Bongrand P. Parasitophorous vacuoles of Leishmania amazonensis-infected macrophages maintain an acidic pH. Infect Immun. 1990 Mar;58(3):779–787. doi: 10.1128/iai.58.3.779-787.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bowman E. J., Siebers A., Altendorf K. Bafilomycins: a class of inhibitors of membrane ATPases from microorganisms, animal cells, and plant cells. Proc Natl Acad Sci U S A. 1988 Nov;85(21):7972–7976. doi: 10.1073/pnas.85.21.7972. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Buchmeier N. A., Heffron F. Induction of Salmonella stress proteins upon infection of macrophages. Science. 1990 May 11;248(4956):730–732. doi: 10.1126/science.1970672. [DOI] [PubMed] [Google Scholar]
  7. Buchmeier N. A., Heffron F. Intracellular survival of wild-type Salmonella typhimurium and macrophage-sensitive mutants in diverse populations of macrophages. Infect Immun. 1989 Jan;57(1):1–7. doi: 10.1128/iai.57.1.1-7.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Coffey J. W., De Duve C. Digestive activity of lysosomes. I. The digestion of proteins by extracts of rat liver lysosomes. J Biol Chem. 1968 Jun 25;243(12):3255–3263. [PubMed] [Google Scholar]
  9. Crowle A. J., Dahl R., Ross E., May M. H. Evidence that vesicles containing living, virulent Mycobacterium tuberculosis or Mycobacterium avium in cultured human macrophages are not acidic. Infect Immun. 1991 May;59(5):1823–1831. doi: 10.1128/iai.59.5.1823-1831.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Fields P. I., Swanson R. V., Haidaris C. G., Heffron F. Mutants of Salmonella typhimurium that cannot survive within the macrophage are avirulent. Proc Natl Acad Sci U S A. 1986 Jul;83(14):5189–5193. doi: 10.1073/pnas.83.14.5189. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Finlay B. B., Falkow S. Virulence factors associated with Salmonella species. Microbiol Sci. 1988 Nov;5(11):324–328. [PubMed] [Google Scholar]
  12. Fortier A. H., Leiby D. A., Narayanan R. B., Asafoadjei E., Crawford R. M., Nacy C. A., Meltzer M. S. Growth of Francisella tularensis LVS in macrophages: the acidic intracellular compartment provides essential iron required for growth. Infect Immun. 1995 Apr;63(4):1478–1483. doi: 10.1128/iai.63.4.1478-1483.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Fridovich I. The biology of oxygen radicals. Science. 1978 Sep 8;201(4359):875–880. doi: 10.1126/science.210504. [DOI] [PubMed] [Google Scholar]
  14. Hackstadt T., Williams J. C. Biochemical stratagem for obligate parasitism of eukaryotic cells by Coxiella burnetii. Proc Natl Acad Sci U S A. 1981 May;78(5):3240–3244. doi: 10.1073/pnas.78.5.3240. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Horwitz M. A., Maxfield F. R. Legionella pneumophila inhibits acidification of its phagosome in human monocytes. J Cell Biol. 1984 Dec;99(6):1936–1943. doi: 10.1083/jcb.99.6.1936. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Kaplan J., Keogh E. A. Analysis of the effect of amines on inhibition of receptor-mediated and fluid-phase pinocytosis in rabbit alveolar macrophages. Cell. 1981 Jun;24(3):925–932. doi: 10.1016/0092-8674(81)90118-5. [DOI] [PubMed] [Google Scholar]
  17. Lukacs G. L., Rotstein O. D., Grinstein S. Phagosomal acidification is mediated by a vacuolar-type H(+)-ATPase in murine macrophages. J Biol Chem. 1990 Dec 5;265(34):21099–21107. [PubMed] [Google Scholar]
  18. Maurin M., Benoliel A. M., Bongrand P., Raoult D. Phagolysosomes of Coxiella burnetii-infected cell lines maintain an acidic pH during persistent infection. Infect Immun. 1992 Dec;60(12):5013–5016. doi: 10.1128/iai.60.12.5013-5016.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Miller S. I., Kukral A. M., Mekalanos J. J. A two-component regulatory system (phoP phoQ) controls Salmonella typhimurium virulence. Proc Natl Acad Sci U S A. 1989 Jul;86(13):5054–5058. doi: 10.1073/pnas.86.13.5054. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Miller S. I., Mekalanos J. J. Constitutive expression of the phoP regulon attenuates Salmonella virulence and survival within macrophages. J Bacteriol. 1990 May;172(5):2485–2490. doi: 10.1128/jb.172.5.2485-2490.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Mukkada A. J., Meade J. C., Glaser T. A., Bonventre P. F. Enhanced metabolism of Leishmania donovani amastigotes at acid pH: an adaptation for intracellular growth. Science. 1985 Sep 13;229(4718):1099–1101. doi: 10.1126/science.4035350. [DOI] [PubMed] [Google Scholar]
  22. Pitt A., Mayorga L. S., Stahl P. D., Schwartz A. L. Alterations in the protein composition of maturing phagosomes. J Clin Invest. 1992 Nov;90(5):1978–1983. doi: 10.1172/JCI116077. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Sansonetti P. J., Ryter A., Clerc P., Maurelli A. T., Mounier J. Multiplication of Shigella flexneri within HeLa cells: lysis of the phagocytic vacuole and plasmid-mediated contact hemolysis. Infect Immun. 1986 Feb;51(2):461–469. doi: 10.1128/iai.51.2.461-469.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Sturgill-Koszycki S., Schlesinger P. H., Chakraborty P., Haddix P. L., Collins H. L., Fok A. K., Allen R. D., Gluck S. L., Heuser J., Russell D. G. Lack of acidification in Mycobacterium phagosomes produced by exclusion of the vesicular proton-ATPase. Science. 1994 Feb 4;263(5147):678–681. doi: 10.1126/science.8303277. [DOI] [PubMed] [Google Scholar]
  25. Tilney L. G., Portnoy D. A. Actin filaments and the growth, movement, and spread of the intracellular bacterial parasite, Listeria monocytogenes. J Cell Biol. 1989 Oct;109(4 Pt 1):1597–1608. doi: 10.1083/jcb.109.4.1597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Wick M. J., Harding C. V., Twesten N. J., Normark S. J., Pfeifer J. D. The phoP locus influences processing and presentation of Salmonella typhimurium antigens by activated macrophages. Mol Microbiol. 1995 May;16(3):465–476. doi: 10.1111/j.1365-2958.1995.tb02411.x. [DOI] [PubMed] [Google Scholar]
  27. Winkler H. H. Rickettsia species (as organisms). Annu Rev Microbiol. 1990;44:131–153. doi: 10.1146/annurev.mi.44.100190.001023. [DOI] [PubMed] [Google Scholar]
  28. Xu H. R., Hsu H. S. Dissemination and proliferation of Salmonella typhimurium in genetically resistant and susceptible mice. J Med Microbiol. 1992 Jun;36(6):377–381. doi: 10.1099/00222615-36-6-377. [DOI] [PubMed] [Google Scholar]

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