Skip to main content
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1987 Jul;169(7):3189–3198. doi: 10.1128/jb.169.7.3189-3198.1987

Cobalamin (vitamin B12) biosynthetic genes of Salmonella typhimurium.

R M Jeter, J R Roth
PMCID: PMC212369  PMID: 3036774

Abstract

The enteric bacterium Salmonella typhimurium synthesizes cobalamin (vitamin B12) de novo only under anaerobic growth conditions. We initiated a genetic analysis of the cobalamin biosynthetic (cob) gene cluster, Stable cob::lac operon fusions were generated by insertions of a transposition-defective derivative of bacteriophage Mu d1 (Ap lac) into the cob genes. beta-Galactosidase synthesis was repressed in the presence of exogenously supplied cyanocobalamin, demonstrating that the cobalamin biosynthetic pathway was regulated by end-product repression. Transcriptional polarity studies showed that the cob genes responsible for synthesis of the corrinoid intermediate cobinamide (branch I of the pathway) were organized into a single operon. Genes for the synthesis of 5,6-dimethylbenzimidazole (branch II) and the final assembly of the complete cobalamin molecule (branch III) were organized into two or more additional operons. All of the known cob genes (in branches I, II, and III) were transcribed in a counterclockwise direction relative to the S. typhimurium genetic map. These genes are located at 41 map units and near the his operon. No essential genes lie between the his and cob operons. Mutants that carried deletions extending from the his genes into the cob region were isolated and characterized. By using these mutants, a deletion map of the branch I cob operon was constructed and the order of genes (his-cobI-cobIII-cobII) was inferred.

Full text

PDF
3190

Selected References

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

  1. Anderson P., Roth J. Spontaneous tandem genetic duplications in Salmonella typhimurium arise by unequal recombination between rRNA (rrn) cistrons. Proc Natl Acad Sci U S A. 1981 May;78(5):3113–3117. doi: 10.1073/pnas.78.5.3113. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Anderson R. P., Roth J. R. Tandem chromosomal duplications in Salmonella typhimurium: fusion of histidine genes to novel promoters. J Mol Biol. 1978 Feb 15;119(1):147–166. doi: 10.1016/0022-2836(78)90274-7. [DOI] [PubMed] [Google Scholar]
  3. Balch W. E., Fox G. E., Magrum L. J., Woese C. R., Wolfe R. S. Methanogens: reevaluation of a unique biological group. Microbiol Rev. 1979 Jun;43(2):260–296. doi: 10.1128/mr.43.2.260-296.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bochner B. R., Huang H. C., Schieven G. L., Ames B. N. Positive selection for loss of tetracycline resistance. J Bacteriol. 1980 Aug;143(2):926–933. doi: 10.1128/jb.143.2.926-933.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Casadaban M. J., Cohen S. N. Lactose genes fused to exogenous promoters in one step using a Mu-lac bacteriophage: in vivo probe for transcriptional control sequences. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4530–4533. doi: 10.1073/pnas.76.9.4530. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Cauthen S. E., Foster M. A., Woods D. D. Methionine synthesis by extracts of Salmonella typhimurium. Biochem J. 1966 Feb;98(2):630–635. doi: 10.1042/bj0980630. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Chang G. W., Chang J. T. Evidence for the B12-dependent enzyme ethanolamine deaminase in Salmonella. Nature. 1975 Mar 13;254(5496):150–151. doi: 10.1038/254150a0. [DOI] [PubMed] [Google Scholar]
  8. Childs J. D., Smith D. A. New methionine structural gene in Salmonella typhimurium. J Bacteriol. 1969 Oct;100(1):377–382. doi: 10.1128/jb.100.1.377-382.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Ciampi M. S., Schmid M. B., Roth J. R. Transposon Tn10 provides a promoter for transcription of adjacent sequences. Proc Natl Acad Sci U S A. 1982 Aug;79(16):5016–5020. doi: 10.1073/pnas.79.16.5016. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Escalante-Semerena J. C., Roth J. R. Regulation of cobalamin biosynthetic operons in Salmonella typhimurium. J Bacteriol. 1987 May;169(5):2251–2258. doi: 10.1128/jb.169.5.2251-2258.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Fink G. R., Klopotowski T., Ames B. N. Histidine regulatory mutants in Salmonella typhimurium. IV. A positive selection for polar histidine-requiring mutants from histidine operator constitutive mutants. J Mol Biol. 1967 Nov 28;30(1):81–95. doi: 10.1016/0022-2836(67)90245-8. [DOI] [PubMed] [Google Scholar]
  12. Hartman P. E., Rusgis C., Stahl R. C. Orientation of the histidine operon in the Salmonella typhimurium linkage map. Proc Natl Acad Sci U S A. 1965 Jun;53(6):1332–1335. doi: 10.1073/pnas.53.6.1332. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hughes K. T., Olivera B. M., Roth J. R. Rec dependence of mu transposition from P22-transduced fragments. J Bacteriol. 1987 Jan;169(1):403–409. doi: 10.1128/jb.169.1.403-409.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hughes K. T., Roth J. R. Conditionally transposition-defective derivative of Mu d1(Amp Lac). J Bacteriol. 1984 Jul;159(1):130–137. doi: 10.1128/jb.159.1.130-137.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Hughes K. T., Roth J. R. Directed formation of deletions and duplications using Mud(Ap, lac). Genetics. 1985 Feb;109(2):263–282. doi: 10.1093/genetics/109.2.263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Jeter R. M., Olivera B. M., Roth J. R. Salmonella typhimurium synthesizes cobalamin (vitamin B12) de novo under anaerobic growth conditions. J Bacteriol. 1984 Jul;159(1):206–213. doi: 10.1128/jb.159.1.206-213.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Johnston H. M., Barnes W. M., Chumley F. G., Bossi L., Roth J. R. Model for regulation of the histidine operon of Salmonella. Proc Natl Acad Sci U S A. 1980 Jan;77(1):508–512. doi: 10.1073/pnas.77.1.508. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kleckner N., Reichardt K., Botstein D. Inversions and deletions of the Salmonella chromosome generated by the translocatable tetracycline resistance element Tn10. J Mol Biol. 1979 Jan 5;127(1):89–115. doi: 10.1016/0022-2836(79)90461-3. [DOI] [PubMed] [Google Scholar]
  19. Kleckner N., Roth J., Botstein D. Genetic engineering in vivo using translocatable drug-resistance elements. New methods in bacterial genetics. J Mol Biol. 1977 Oct 15;116(1):125–159. doi: 10.1016/0022-2836(77)90123-1. [DOI] [PubMed] [Google Scholar]
  20. Maloy S. R., Nunn W. D. Selection for loss of tetracycline resistance by Escherichia coli. J Bacteriol. 1981 Feb;145(2):1110–1111. doi: 10.1128/jb.145.2.1110-1111.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Sanderson K. E., Roth J. R. Linkage map of Salmonella typhimurium, Edition VI. Microbiol Rev. 1983 Sep;47(3):410–453. doi: 10.1128/mr.47.3.410-453.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Silhavy T. J., Beckwith J. R. Uses of lac fusions for the study of biological problems. Microbiol Rev. 1985 Dec;49(4):398–418. doi: 10.1128/mr.49.4.398-418.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Simons R. W., Hoopes B. C., McClure W. R., Kleckner N. Three promoters near the termini of IS10: pIN, pOUT, and pIII. Cell. 1983 Sep;34(2):673–682. doi: 10.1016/0092-8674(83)90400-2. [DOI] [PubMed] [Google Scholar]
  24. Smith H. O., Levine M. A phage P22 gene controlling integration of prophage. Virology. 1967 Feb;31(2):207–216. doi: 10.1016/0042-6822(67)90164-x. [DOI] [PubMed] [Google Scholar]
  25. VOGEL H. J., BONNER D. M. Acetylornithinase of Escherichia coli: partial purification and some properties. J Biol Chem. 1956 Jan;218(1):97–106. [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES