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. 1997 Dec;179(23):7264–7273. doi: 10.1128/jb.179.23.7264-7273.1997

Analysis of the fnrL gene and its function in Rhodobacter capsulatus.

J H Zeilstra-Ryalls 1, K Gabbert 1, N J Mouncey 1, S Kaplan 1, R G Kranz 1
PMCID: PMC179675  PMID: 9393689

Abstract

The fnr gene encodes a regulatory protein involved in the response to oxygen in a variety of bacterial genera. For example, it was previously shown that the anoxygenic, photosynthetic bacterium Rhodobacter sphaeroides requires the fnrL gene for growth under anaerobic, photosynthetic conditions. Additionally, the FnrL protein in R. sphaeroides is required for anaerobic growth in the dark with an alternative electron acceptor, but it is not essential for aerobic growth. In this study, the fnrL locus from Rhodobacter capsulatus was cloned and sequenced. Surprisingly, an R. capsulatus strain with the fnrL gene deleted grows like the wild type under either photosynthetic or aerobic conditions but does not grow anaerobically with alternative electron acceptors such as dimethyl sulfoxide (DMSO) or trimethylamine oxide. It is demonstrated that the c-type cytochrome induced upon anaerobic growth on DMSO is not synthesized in the R. capsulatus fnrL mutant. In contrast to wild-type strains, R. sphaeroides and R. capsulatus fnrL mutants do not synthesize the anaerobically, DMSO-induced reductase. Mechanisms that explain the basis for FnrL function in both organisms are discussed.

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Selected References

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  1. Altschul S. F., Gish W., Miller W., Myers E. W., Lipman D. J. Basic local alignment search tool. J Mol Biol. 1990 Oct 5;215(3):403–410. doi: 10.1016/S0022-2836(05)80360-2. [DOI] [PubMed] [Google Scholar]
  2. Avtges P., Kranz R. G., Haselkorn R. Isolation and organization of genes for nitrogen fixation in Rhodopseudomonas capsulata. Mol Gen Genet. 1985;201(3):363–369. doi: 10.1007/BF00331324. [DOI] [PubMed] [Google Scholar]
  3. Bartnikas T. B., Tosques I. E., Laratta W. P., Shi J., Shapleigh J. P. Characterization of the nitric oxide reductase-encoding region in Rhodobacter sphaeroides 2.4.3. J Bacteriol. 1997 Jun;179(11):3534–3540. doi: 10.1128/jb.179.11.3534-3540.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bauer C. E., Bird T. H. Regulatory circuits controlling photosynthesis gene expression. Cell. 1996 Apr 5;85(1):5–8. doi: 10.1016/s0092-8674(00)81074-0. [DOI] [PubMed] [Google Scholar]
  5. Bauer C., Buggy J., Mosley C. Control of photosystem genes in Rhodobacter capsulatus. Trends Genet. 1993 Feb;9(2):56–60. doi: 10.1016/0168-9525(93)90188-N. [DOI] [PubMed] [Google Scholar]
  6. Boyer H. W., Roulland-Dussoix D. A complementation analysis of the restriction and modification of DNA in Escherichia coli. J Mol Biol. 1969 May 14;41(3):459–472. doi: 10.1016/0022-2836(69)90288-5. [DOI] [PubMed] [Google Scholar]
  7. Cao J., Hosler J., Shapleigh J., Revzin A., Ferguson-Miller S. Cytochrome aa3 of Rhodobacter sphaeroides as a model for mitochondrial cytochrome c oxidase. The coxII/coxIII operon codes for structural and assembly proteins homologous to those in yeast. J Biol Chem. 1992 Dec 5;267(34):24273–24278. [PubMed] [Google Scholar]
  8. Coomber S. A., Jones R. M., Jordan P. M., Hunter C. N. A putative anaerobic coproporphyrinogen III oxidase in Rhodobacter sphaeroides. I. Molecular cloning, transposon mutagenesis and sequence analysis of the gene. Mol Microbiol. 1992 Nov;6(21):3159–3169. doi: 10.1111/j.1365-2958.1992.tb01772.x. [DOI] [PubMed] [Google Scholar]
  9. Cotter P. A., Gunsalus R. P. Oxygen, nitrate, and molybdenum regulation of dmsABC gene expression in Escherichia coli. J Bacteriol. 1989 Jul;171(7):3817–3823. doi: 10.1128/jb.171.7.3817-3823.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Davis J., Donohue T. J., Kaplan S. Construction, characterization, and complementation of a Puf- mutant of Rhodobacter sphaeroides. J Bacteriol. 1988 Jan;170(1):320–329. doi: 10.1128/jb.170.1.320-329.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Ditta G., Stanfield S., Corbin D., Helinski D. R. Broad host range DNA cloning system for gram-negative bacteria: construction of a gene bank of Rhizobium meliloti. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7347–7351. doi: 10.1073/pnas.77.12.7347. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Eraso J. M., Kaplan S. Oxygen-insensitive synthesis of the photosynthetic membranes of Rhodobacter sphaeroides: a mutant histidine kinase. J Bacteriol. 1995 May;177(10):2695–2706. doi: 10.1128/jb.177.10.2695-2706.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gomelsky M., Kaplan S. Genetic evidence that PpsR from Rhodobacter sphaeroides 2.4.1 functions as a repressor of puc and bchF expression. J Bacteriol. 1995 Mar;177(6):1634–1637. doi: 10.1128/jb.177.6.1634-1637.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gomelsky M., Kaplan S. appA, a novel gene encoding a trans-acting factor involved in the regulation of photosynthesis gene expression in Rhodobacter sphaeroides 2.4.1. J Bacteriol. 1995 Aug;177(16):4609–4618. doi: 10.1128/jb.177.16.4609-4618.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Gray K. A., Grooms M., Myllykallio H., Moomaw C., Slaughter C., Daldal F. Rhodobacter capsulatus contains a novel cb-type cytochrome c oxidase without a CuA center. Biochemistry. 1994 Mar 15;33(10):3120–3127. doi: 10.1021/bi00176a047. [DOI] [PubMed] [Google Scholar]
  16. Haydon D. J., Quail M. A., Guest J. R. A mutation causing constitutive synthesis of the pyruvate dehydrogenase complex in Escherichia coli is located within the pdhR gene. FEBS Lett. 1993 Dec 20;336(1):43–47. doi: 10.1016/0014-5793(93)81605-y. [DOI] [PubMed] [Google Scholar]
  17. Hornberger U., Liebetanz R., Tichy H. V., Drews G. Cloning and sequencing of the hemA gene of Rhodobacter capsulatus and isolation of a delta-aminolevulinic acid-dependent mutant strain. Mol Gen Genet. 1990 May;221(3):371–378. doi: 10.1007/BF00259402. [DOI] [PubMed] [Google Scholar]
  18. Jenney F. E., Jr, Daldal F. A novel membrane-associated c-type cytochrome, cyt cy, can mediate the photosynthetic growth of Rhodobacter capsulatus and Rhodobacter sphaeroides. EMBO J. 1993 Apr;12(4):1283–1292. doi: 10.1002/j.1460-2075.1993.tb05773.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Keen N. T., Tamaki S., Kobayashi D., Trollinger D. Improved broad-host-range plasmids for DNA cloning in gram-negative bacteria. Gene. 1988 Oct 15;70(1):191–197. doi: 10.1016/0378-1119(88)90117-5. [DOI] [PubMed] [Google Scholar]
  20. Klug G. Regulation of expression of photosynthesis genes in anoxygenic photosynthetic bacteria. Arch Microbiol. 1993;159(5):397–404. doi: 10.1007/BF00288584. [DOI] [PubMed] [Google Scholar]
  21. Kranz R. G. Isolation of mutants and genes involved in cytochromes c biosynthesis in Rhodobacter capsulatus. J Bacteriol. 1989 Jan;171(1):456–464. doi: 10.1128/jb.171.1.456-464.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Lee J. K., Kaplan S. Isolation and characterization of trans-acting mutations involved in oxygen regulation of puc operon transcription in Rhodobacter sphaeroides. J Bacteriol. 1992 Feb;174(4):1158–1171. doi: 10.1128/jb.174.4.1158-1171.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Mosley C. S., Suzuki J. Y., Bauer C. E. Identification and molecular genetic characterization of a sensor kinase responsible for coordinately regulating light harvesting and reaction center gene expression in response to anaerobiosis. J Bacteriol. 1994 Dec;176(24):7566–7573. doi: 10.1128/jb.176.24.7566-7573.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Neidle E. L., Kaplan S. Expression of the Rhodobacter sphaeroides hemA and hemT genes, encoding two 5-aminolevulinic acid synthase isozymes. J Bacteriol. 1993 Apr;175(8):2292–2303. doi: 10.1128/jb.175.8.2292-2303.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. O'Gara J. P., Kaplan S. Evidence for the role of redox carriers in photosynthesis gene expression and carotenoid biosynthesis in Rhodobacter sphaeroides 2.4.1. J Bacteriol. 1997 Mar;179(6):1951–1961. doi: 10.1128/jb.179.6.1951-1961.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Pascal M. C., Burini J. F., Chippaux M. Regulation of the trimethylamine N-oxide (TMAO) reductase in Escherichia coli: analysis of tor::Mud1 operon fusion. Mol Gen Genet. 1984;195(1-2):351–355. doi: 10.1007/BF00332770. [DOI] [PubMed] [Google Scholar]
  27. Penfold R. J., Pemberton J. M. Sequencing, chromosomal inactivation, and functional expression in Escherichia coli of ppsR, a gene which represses carotenoid and bacteriochlorophyll synthesis in Rhodobacter sphaeroides. J Bacteriol. 1994 May;176(10):2869–2876. doi: 10.1128/jb.176.10.2869-2876.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Ponnampalam S. N., Buggy J. J., Bauer C. E. Characterization of an aerobic repressor that coordinately regulates bacteriochlorophyll, carotenoid, and light harvesting-II expression in Rhodobacter capsulatus. J Bacteriol. 1995 Jun;177(11):2990–2997. doi: 10.1128/jb.177.11.2990-2997.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. 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]
  30. Sganga M. W., Bauer C. E. Regulatory factors controlling photosynthetic reaction center and light-harvesting gene expression in Rhodobacter capsulatus. Cell. 1992 Mar 6;68(5):945–954. doi: 10.1016/0092-8674(92)90037-d. [DOI] [PubMed] [Google Scholar]
  31. Shapleigh J. P., Gennis R. B. Cloning, sequencing and deletion from the chromosome of the gene encoding subunit I of the aa3-type cytochrome c oxidase of Rhodobacter sphaeroides. Mol Microbiol. 1992 Mar;6(5):635–642. doi: 10.1111/j.1365-2958.1992.tb01511.x. [DOI] [PubMed] [Google Scholar]
  32. Spiro S. The FNR family of transcriptional regulators. Antonie Van Leeuwenhoek. 1994;66(1-3):23–36. doi: 10.1007/BF00871630. [DOI] [PubMed] [Google Scholar]
  33. Suwanto A., Kaplan S. Physical and genetic mapping of the Rhodobacter sphaeroides 2.4.1 genome: genome size, fragment identification, and gene localization. J Bacteriol. 1989 Nov;171(11):5840–5849. doi: 10.1128/jb.171.11.5840-5849.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Tai T. N., Moore M. D., Kaplan S. Cloning and characterization of the 5-aminolevulinate synthase gene(s) from Rhodobacter sphaeroides. Gene. 1988 Oct 15;70(1):139–151. doi: 10.1016/0378-1119(88)90112-6. [DOI] [PubMed] [Google Scholar]
  35. Thomas P. E., Ryan D., Levin W. An improved staining procedure for the detection of the peroxidase activity of cytochrome P-450 on sodium dodecyl sulfate polyacrylamide gels. Anal Biochem. 1976 Sep;75(1):168–176. doi: 10.1016/0003-2697(76)90067-1. [DOI] [PubMed] [Google Scholar]
  36. Thöny-Meyer L., Beck C., Preisig O., Hennecke H. The ccoNOQP gene cluster codes for a cb-type cytochrome oxidase that functions in aerobic respiration of Rhodobacter capsulatus. Mol Microbiol. 1994 Nov;14(4):705–716. doi: 10.1111/j.1365-2958.1994.tb01308.x. [DOI] [PubMed] [Google Scholar]
  37. Tosques I. E., Kwiatkowski A. V., Shi J., Shapleigh J. P. Characterization and regulation of the gene encoding nitrite reductase in Rhodobacter sphaeroides 2.4.3. J Bacteriol. 1997 Feb;179(4):1090–1095. doi: 10.1128/jb.179.4.1090-1095.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Tosques I. E., Shi J., Shapleigh J. P. Cloning and characterization of nnrR, whose product is required for the expression of proteins involved in nitric oxide metabolism in Rhodobacter sphaeroides 2.4.3. J Bacteriol. 1996 Aug;178(16):4958–4964. doi: 10.1128/jb.178.16.4958-4964.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Weaver P. F., Wall J. D., Gest H. Characterization of Rhodopseudomonas capsulata. Arch Microbiol. 1975 Nov 7;105(3):207–216. doi: 10.1007/BF00447139. [DOI] [PubMed] [Google Scholar]
  40. Yen H. C., Marrs B. Map of genes for carotenoid and bacteriochlorophyll biosynthesis in Rhodopseudomonas capsulata. J Bacteriol. 1976 May;126(2):619–629. doi: 10.1128/jb.126.2.619-629.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Youvan D. C., Ismail S. Light-harvesting II (B800-B850 complex) structural genes from Rhodopseudomonas capsulata. Proc Natl Acad Sci U S A. 1985 Jan;82(1):58–62. doi: 10.1073/pnas.82.1.58. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Zeilstra-Ryalls J. H., Kaplan S. Aerobic and anaerobic regulation in Rhodobacter sphaeroides 2.4.1: the role of the fnrL gene. J Bacteriol. 1995 Nov;177(22):6422–6431. doi: 10.1128/jb.177.22.6422-6431.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Zeilstra-Ryalls J. H., Kaplan S. Regulation of 5-aminolevulinic acid synthesis in Rhodobacter sphaeroides 2.4.1: the genetic basis of mutant H-5 auxotrophy. J Bacteriol. 1995 May;177(10):2760–2768. doi: 10.1128/jb.177.10.2760-2768.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. de Gier J. W., Schepper M., Reijnders W. N., van Dyck S. J., Slotboom D. J., Warne A., Saraste M., Krab K., Finel M., Stouthamer A. H. Structural and functional analysis of aa3-type and cbb3-type cytochrome c oxidases of Paracoccus denitrificans reveals significant differences in proton-pump design. Mol Microbiol. 1996 Jun;20(6):1247–1260. doi: 10.1111/j.1365-2958.1996.tb02644.x. [DOI] [PubMed] [Google Scholar]
  45. van Niel C. B. THE CULTURE, GENERAL PHYSIOLOGY, MORPHOLOGY, AND CLASSIFICATION OF THE NON-SULFUR PURPLE AND BROWN BACTERIA. Bacteriol Rev. 1944 Mar;8(1):1–118. doi: 10.1128/br.8.1.1-118.1944. [DOI] [PMC free article] [PubMed] [Google Scholar]

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