Skip to content
naulon

No retraction, correction or concern found when last checked on Oct 31, 2026.

Acid pH activation of the PmrA/PmrB two‐component regulatory system of Salmonella enterica

J. Christian Perez, Eduardo A. Groisman

Molecular Microbiology · 2006

doi:10.1111/j.1365-2958.2006.05512.x

Abstract

Summary Acid pH often triggers changes in gene expression. However, little is known about the identity of the gene products that sense fluctuations in extracytoplasmic pH. The Gram‐negative pathogen Salmonella enterica serovar Typhimurium experiences a number of acidic environments both inside and outside animal hosts. Growth in mild acid (pH 5.8) promotes transcription of genes activated by the response regulator PmrA, but the signalling pathway(s) that mediates this response has thus far remained unexplored. Here we report that this activation requires both PmrA's cognate sensor kinase PmrB, which had been previously shown to respond to Fe 3+ and Al 3+ , and PmrA's post‐translational activator PmrD. Substitution of a conserved histidine or of either one of four conserved glutamic acid residues in the periplasmic domain of PmrB severely decreased or abolished the mild acid‐promoted transcription of PmrA‐activated genes. The PmrA/PmrB system controls lipopolysaccharide modifications mediating resistance to the antibiotic polymyxin B. Wild‐type Salmonella grown at pH 5.8 were > 100 000‐fold more resistant to polymyxin B than organisms grown at pH 7.7. Our results suggest that protonation of the PmrB periplasmic histidine and/or of the glutamic acid residues activate the PmrA protein, and that mild acid promotes cellular changes resulting in polymyxin B resistance.

Shown for reading. Its publisher allows quoting it, not republishing it.

References 53

  1. 1.

    Aranda CMA, Swanson JA, Loomis WP, Miller SI. Salmonella typhimurium activates virulence gene transcription within acidified macrophage phagosomes. Proc Natl Acad Sci USA. 1992;89:10079-10083.

    Not in our library10.1073/pnas.89.21.10079

  2. 2.

    Bearson BL, Wilson L, Foster JW. A low pH-inducible, PhoPQ-dependent acid tolerance response protects Salmonella typhimurium against inorganic acid stress. J Bacteriol. 1998;180:2409-2417.

    Not in our library10.1128/jb.180.9.2409-2417.1998

  3. 3.

    Breazeale SD, Ribeiro AA, Raetz CRH. Origin of lipid A species modified with 4-amino-4-deoxy-l-arabinose in polymyxin-resistant mutants of Escherichia coli: an aminotransferase (ArnB) that generates UDP-4-amino-4-deoxy-l-arabinose. J Biol Chem. 2003;278:24731-24739.

    Not in our library10.1074/jbc.m304043200

  4. 4.

    Brumell JH, Grinstein S. Salmonella redirects phagosomal maturation. Curr Opin Microbiol. 2004;7:78-84.

    Not in our library10.1016/j.mib.2003.12.005

  5. 5.

    Chamnongpol S, Dodson W, Cromie MJ, Harris ZL, Groisman EA. Fe(III)-mediated cellular toxicity. Mol Microbiol. 2002;45:711-719.

    Not in our library10.1046/j.1365-2958.2002.03041.x

  6. 6.

    Cherepanov PP, Wackernagel W. Gene disruption in Escherichia coli– TcR and KmR cassettes with the option of Flp-catalyzed excision of the antibiotic-resistance determinant. Gene. 1995;158:9-14.

    Not in our library10.1016/0378-1119(95)00193-a

  7. 7.

    Datsenko KA, Wanner BL. One-step inactivation of chromosomal genes in Escherichia coli K-12 using PCR products. Proc Natl Acad Sci USA. 2000;97:6640-6645.

    Not in our library10.1073/pnas.120163297

  8. 8.

    Davis RW, Bolstein D, Roth JR. Advanced Bacterial Genetics. 1980.

    Not in our library

  9. 9.

    Delgado MA, Mouslim C, Groisman EA. The PmrA/PmrB and RcsC/YojN/RcsB systems control expression of the Salmonella O-antigen chain length determinant. Mol Microbiol. 2006;60:39-50.

    Not in our library10.1111/j.1365-2958.2006.05069.x

  10. 10.

    Dell CL, Neely MN, Olson ER. Altered pH and lysine signaling mutants of cadC, a gene encoding a membrane-bound transcriptional activator of the Escherichia coli cadBA operon. Mol Microbiol. 1994;14:7-16.

    Not in our library10.1111/j.1365-2958.1994.tb01262.x

  11. 11.

    Foster JW. Low pH adaptation and the acid tolerance response of Salmonella typhimurium. Crit Rev Microbiol. 1995;21:215-237.

    Not in our library10.3109/10408419509113541

  12. 12.

    Foster JW. Escherichia coli acid resistance: tales of an amateur acidophile. Nat Rev Microbiol. 2004;2:898-907.

    Not in our library10.1038/nrmicro1021

  13. 13.

    Foster JW, Hall HK. Adaptive acidification tolerance response of Salmonella typhimurium. J Bacteriol. 1990;172:771-778.

    Not in our library10.1128/jb.172.2.771-778.1990

  14. 14.

    Gibbons HS, Kalb SR, Cotter RJ, Raetz CRH. Role of Mg2+ and pH in the modification of Salmonella lipid A after endocytosis by macrophage tumour cells. Mol Microbiol. 2005;55:425-440.

    Not in our library10.1111/j.1365-2958.2004.04409.x

  15. 15.

    Groisman EA, Mouslim C. Sensing by bacterial regulatory systems in host and non-host environments. Nat Rev Microbiol. 2006;4:705-709.

    Not in our library10.1038/nrmicro1478

  16. 16.

    Groisman EA, Heffron F, Solomon F. Molecular genetic analysis of the Escherichia coli phoP locus. J Bacteriol. 1992;174:486-491.

    Not in our library10.1128/jb.174.2.486-491.1992

  17. 17.

    Gunn JS, Lim KB, Krueger J, Kim K, Guo L, Hackett M, Miller SI. PmrA-PmrB-regulated genes necessary for 4-aminoarabinose lipid A modification and polymyxin resistance. Mol Microbiol. 1998;27:1171-1182.

    Not in our library10.1046/j.1365-2958.1998.00757.x

  18. 18.

    Gunn JS, Ryan SS, Van Velkinburgh JC, Ernst RK, Miller SI. Genetic and functional analysis of a PmrA-PmrB-regulated locus necessary for lipopolysaccharide modification, antimicrobial peptide resistance, and oral virulence of Salmonella enterica serovar Typhimurium. Infect Immun. 2000;68:6139-6146.

    Not in our library10.1128/iai.68.11.6139-6146.2000

  19. 19.

    Hall HK, Foster JW. The role of Fur in the acid tolerance response of Salmonella typhimurium is physiologically and genetically separable from its role in iron acquisition. J Bacteriol. 1996;178:5683-5691.

    Not in our library10.1128/jb.178.19.5683-5691.1996

  20. 20.

    Hanahan D. Studies on transformation of Escherichia coli with plasmids. J Mol Biol. 1983;166:557-580.

    Not in our library10.1016/s0022-2836(83)80284-8

  21. 21.

    Iwama T, Ito Y, Aoki H, Sakamoto H, Yamagata S, Kawai K, Kawagishi I. Differential recognition of citrate and metal-citrate complex by the bacterial chemoreceptor Tcp. J Biol Chem. 2006;281:17727-17735.

    Not in our library10.1074/jbc.m601038200

  22. 22.

    Kato A, Groisman EA. Connecting two-component regulatory systems by a protein that protects a response regulator from dephosphorylation by its cognate sensor. Gene Dev. 2004;18:2302-2313.

    Not in our library10.1101/gad.1230804

  23. 23.

    Kox LFF, Wosten MMSM, Groisman EA. A small protein that mediates the activation of a two-component system by another two-component system. EMBO J. 2000;19:1861-1872.

    Not in our library10.1093/emboj/19.8.1861

  24. 24.

    Leaphart AB, Thompson DK, Huang K, Alm E, Wan XF, Arkin A, et al. Transcriptome profiling of Shewanella oneidensis gene expression following exposure to acidic and alkaline pH. J Bacteriol. 2006;188:1633-1642.

    Not in our library10.1128/jb.188.4.1633-1642.2006

  25. 25.

    Lee H, Hsu FF, Turk J, Groisman EA. The PmrA-regulated pmrC gene mediates phosphoethanolamine modification of lipid A and polymyxin resistance in Salmonella enterica. J Bacteriol. 2004;186:4124-4133.

    Not in our library10.1128/jb.186.13.4124-4133.2004

  26. 26.

    Lu J, Edwards RA, Wong JJW, Manchak J, Scott PG, Frost LS, Glover JN. Protonation-mediated structural flexibility in the F conjugation regulatory protein, TraM. EMBO J. 2006;25:2930-2939.

    Not in our library10.1038/sj.emboj.7601151

  27. 27.

    Ludwig MG, Vanek M, Guerini D, Gasser JA, Jones CE, Junker U, et al. Proton-sensing G-protein-coupled receptors. Nature. 2003;425:93-98.

    Not in our library10.1038/nature01905

  28. 28.

    McGowan CC, Necheva AS, Forsyth MH, Cover TL, Blaser MJ. Promoter analysis of Helicobacter pylori genes with enhanced expression at low pH. Mol Microbiol. 2003;48:1225-1239.

    Not in our library10.1046/j.1365-2958.2003.03500.x

  29. 29.

    Marchal K, De Keersmaecker S, Monsieurs P, van Boxel N, Lemmens K, Thijs G, et al. In silico identification and experimental validation of PmrAB targets in Salmonella typhimurium by regulatory motif detection. Genome Biol. 2004;5:R9.

    Not in our library10.1186/gb-2004-5-2-r9

  30. 30.

    Miller JH. Experiments in Molecular Genetics. 1972.

    Not in our library

  31. 31.

    Nishino K, Hsu FF, Turk J, Cromie MJ, Wosten MM, Groisman EA. Identification of the lipopolysaccharide modifications controlled by the Salmonella PmrA/PmrB system mediating resistance to Fe(III) and Al(III). Mol Microbiol. 2006;61:645-654.

    Not in our library10.1111/j.1365-2958.2006.05273.x

  32. 32.

    Paulus H, Gray E. The biosynthesis of polymyxin B by growing cultures of Bacillus polymyxa. J Biol Chem. 1964;239:865-871.

    Not in our library

  33. 33.

    Roland KL, Martin LE, Esther CR, Spitznagel JK. Spontaneous PmrA mutants of Salmonella typhimurium LT2 define a new two-component regulatory system with a possible role in virulence. J Bacteriol. 1993;175:4154-4164.

    Not in our library10.1128/jb.175.13.4154-4164.1993

  34. 34.

    Rychlik I, Barrow PA. Salmonella stress management and its relevance to behaviour during intestinal colonization and infection. FEMS Microbiol Rev. 2005;29:1021-1040.

    Not in our library10.1016/j.femsre.2005.03.005

  35. 35.

    Shin D, Groisman EA. Signal-dependent binding of the response regulators PhoP and PmrA to their target promoters in vivo. J Biol Chem. 2005;280:4089-4094.

    Not in our library10.1074/jbc.m412741200

  36. 36.

    Slonczewski JL, Rosen BP, Alger JR, Macnab RM. pH homeostasis in Escherichia coli: measurement by 31P nuclear magnetic resonance of methylphosphonate and phosphate. Proc Natl Acad Sci USA. 1981;78:6271-6275.

    Not in our library10.1073/pnas.78.10.6271

  37. 37.

    Snavely MD, Gravina SA, Cheung TT, Miller CG, Maguire ME. Magnesium transport in Salmonella typhimurium– regulation of MgtA and MgtB expression. J Biol Chem. 1991;266:824-829.

    Not in our library

  38. 38.

    Soncini FC, Groisman EA. Two-component regulatory systems can interact to process multiple environmental signals. J Bacteriol. 1996;178:6796-6801.

    Not in our library10.1128/jb.178.23.6796-6801.1996

  39. 39.

    Soncini FC, Vescovi EG, Groisman EA. Transcriptional autoregulation of the Salmonella typhimurium phoPQ operon. J Bacteriol. 1995;177:4364-4371.

    Not in our library10.1128/jb.177.15.4364-4371.1995

  40. 40.

    Soncini FC, Vescovi EG, Solomon F, Groisman EA. Molecular basis of the magnesium deprivation response in Salmonella typhimurium: identification of PhoP-regulated genes. J Bacteriol. 1996;178:5092-5099.

    Not in our library10.1128/jb.178.17.5092-5099.1996

All 53 references

Cited by papers we hold 7

Reads

Read by people on this page

None yet.

Checked or read by AI through naulon

None yet.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.

Are you an author?

Is this your paper?

Claim it to add your note and be paid when agents cite it. Free.