Skip to main content
PMC home page
Infection and Immunity logoLink to Infection and Immunity
. 1991 Jun;59(6):1899–1904. doi: 10.1128/iai.59.6.1899-1904.1991

Iron-dependent regulation of diphtheria toxin and siderophore expression by the cloned Corynebacterium diphtheriae repressor gene dtxR in C. diphtheriae C7 strains.

M P Schmitt 1, R K Holmes 1
PMCID: PMC257940  PMID: 1828057

Abstract

A regulatory gene (dtxR) responsible for iron-dependent repression of the toxin (tox) and siderophore genes in Corynebacterium diphtheriae was cloned and characterized. A DNA fragment carrying dtxR repressed expression of a tox-lacZ gene fusion in Escherichia coli DH5 alpha in a high-iron environment but not under low-iron conditions. A protein with mobility corresponding to approximately 28 to 29 kDa was identified as the product of the dtxR gene by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A shuttle vector designated pCM2.6 was constructed which carries the origin of replication from C. diphtheriae plasmid pNG2 and confers resistance to chloramphenicol in E. coli and C. diphtheriae. DNA fragments carrying dtxR were cloned into pCM2.6, and the hybrid shuttle plasmids were transformed by electroporation into wild-type C. diphtheriae C7(beta) and the regulatory mutant C7(beta)hm723, which produces toxin and siderophore constitutively under high-iron conditions. Expression of the cloned dtxR determinant did not affect the phenotype of C. diphtheriae C7(beta). In C. diphtheriae C7(beta)hm723, expression of cloned dtxR restored full repression of siderophore production and partial repression of diphtheria toxin production during growth in a high-iron environment.

Full text

PDF
1899

Images in this article

1901Image
on p.1901

Selected References

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

  1. Bagg A., Neilands J. B. Molecular mechanism of regulation of siderophore-mediated iron assimilation. Microbiol Rev. 1987 Dec;51(4):509–518. doi: 10.1128/mr.51.4.509-518.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Boyd J., Oza M. N., Murphy J. R. Molecular cloning and DNA sequence analysis of a diphtheria tox iron-dependent regulatory element (dtxR) from Corynebacterium diphtheriae. Proc Natl Acad Sci U S A. 1990 Aug;87(15):5968–5972. doi: 10.1073/pnas.87.15.5968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Casadaban M. J., Chou J., Cohen S. N. In vitro gene fusions that join an enzymatically active beta-galactosidase segment to amino-terminal fragments of exogenous proteins: Escherichia coli plasmid vectors for the detection and cloning of translational initiation signals. J Bacteriol. 1980 Aug;143(2):971–980. doi: 10.1128/jb.143.2.971-980.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Chang A. C., Cohen S. N. Construction and characterization of amplifiable multicopy DNA cloning vehicles derived from the P15A cryptic miniplasmid. J Bacteriol. 1978 Jun;134(3):1141–1156. doi: 10.1128/jb.134.3.1141-1156.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cryz S. J., Jr, Russell L. M., Holmes R. K. Regulation of toxinogenesis in Corynebacterium diphtheriae: mutations in the bacterial genome that alter the effects of iron on toxin production. J Bacteriol. 1983 Apr;154(1):245–252. doi: 10.1128/jb.154.1.245-252.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Devereux J., Haeberli P., Smithies O. A comprehensive set of sequence analysis programs for the VAX. Nucleic Acids Res. 1984 Jan 11;12(1 Pt 1):387–395. doi: 10.1093/nar/12.1part1.387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hanahan D. Studies on transformation of Escherichia coli with plasmids. J Mol Biol. 1983 Jun 5;166(4):557–580. doi: 10.1016/s0022-2836(83)80284-8. [DOI] [PubMed] [Google Scholar]
  8. Holmes D. S., Quigley M. A rapid boiling method for the preparation of bacterial plasmids. Anal Biochem. 1981 Jun;114(1):193–197. doi: 10.1016/0003-2697(81)90473-5. [DOI] [PubMed] [Google Scholar]
  9. Holmes R. K., Barksdale L. Genetic analysis of tox+ and tox- bacteriophages of Corynebacterium diphtheriae. J Virol. 1969 Jun;3(6):586–598. doi: 10.1128/jvi.3.6.586-598.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kanei C., Uchida T., Yoneda M. Isolation from corynebacterium diphtheriae C7(beta) of bacterial mutants that produce toxin in medium with excess iron. Infect Immun. 1977 Oct;18(1):203–209. doi: 10.1128/iai.18.1.203-209.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Murphy J. R., Pappenheimer A. M., Jr, de Borms S. T. Synthesis of diphtheria tox-gene products in Escherichia coli extracts. Proc Natl Acad Sci U S A. 1974 Jan;71(1):11–15. doi: 10.1073/pnas.71.1.11. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Murphy J. R., Skiver J., McBride G. Isolation and partial characterization of a corynebacteriophage beta, tox operator constitutive-like mutant lysogen of Corynebacterium diphtheriae. J Virol. 1976 Apr;18(1):235–244. doi: 10.1128/jvi.18.1.235-244.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Norrander J., Kempe T., Messing J. Construction of improved M13 vectors using oligodeoxynucleotide-directed mutagenesis. Gene. 1983 Dec;26(1):101–106. doi: 10.1016/0378-1119(83)90040-9. [DOI] [PubMed] [Google Scholar]
  14. Pappenheimer A. M., Jr Diphtheria toxin. Annu Rev Biochem. 1977;46:69–94. doi: 10.1146/annurev.bi.46.070177.000441. [DOI] [PubMed] [Google Scholar]
  15. Russell L. M., Cryz S. J., Jr, Holmes R. K. Genetic and biochemical evidence for a siderophore-dependent iron transport system in Corynebacterium diphtheriae. Infect Immun. 1984 Jul;45(1):143–149. doi: 10.1128/iai.45.1.143-149.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Russell L. M., Holmes R. K. Initial characterization of the ferric iron transport system of Corynebacterium diphtheriae. J Bacteriol. 1983 Sep;155(3):1439–1442. doi: 10.1128/jb.155.3.1439-1442.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Schiller J., Groman N., Coyle M. Plasmids in Corynebacterium diphtheriae and diphtheroids mediating erythromycin resistance. Antimicrob Agents Chemother. 1980 Nov;18(5):814–821. doi: 10.1128/aac.18.5.814. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Schwyn B., Neilands J. B. Universal chemical assay for the detection and determination of siderophores. Anal Biochem. 1987 Jan;160(1):47–56. doi: 10.1016/0003-2697(87)90612-9. [DOI] [PubMed] [Google Scholar]
  19. Schäffer S., Hantke K., Braun V. Nucleotide sequence of the iron regulatory gene fur. Mol Gen Genet. 1985;200(1):110–113. doi: 10.1007/BF00383321. [DOI] [PubMed] [Google Scholar]
  20. Seifert H. S., Ajioka R. S., Marchal C., Sparling P. F., So M. DNA transformation leads to pilin antigenic variation in Neisseria gonorrhoeae. Nature. 1988 Nov 24;336(6197):392–395. doi: 10.1038/336392a0. [DOI] [PubMed] [Google Scholar]
  21. Serwold-Davis T. M., Groman N. B., Kao C. C. Localization of an origin of replication in Corynebacterium diphtheriae broad host range plasmid pNG2 that also functions in Escherichia coli. FEMS Microbiol Lett. 1990 Jan 1;54(1-3):119–123. doi: 10.1016/0378-1097(90)90268-u. [DOI] [PubMed] [Google Scholar]
  22. Serwold-Davis T. M., Groman N., Rabin M. Transformation of Corynebacterium diphtheriae, Corynebacterium ulcerans, Corynebacterium glutamicum, and Escherichia coli with the C. diphtheriae plasmid pNG2. Proc Natl Acad Sci U S A. 1987 Jul;84(14):4964–4968. doi: 10.1073/pnas.84.14.4964. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Tabor S., Richardson C. C. A bacteriophage T7 RNA polymerase/promoter system for controlled exclusive expression of specific genes. Proc Natl Acad Sci U S A. 1985 Feb;82(4):1074–1078. doi: 10.1073/pnas.82.4.1074. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Tai S. P., Holmes R. K. Iron regulation of the cloned diphtheria toxin promoter in Escherichia coli. Infect Immun. 1988 Sep;56(9):2430–2436. doi: 10.1128/iai.56.9.2430-2436.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Tai S. P., Krafft A. E., Nootheti P., Holmes R. K. Coordinate regulation of siderophore and diphtheria toxin production by iron in Corynebacterium diphtheriae. Microb Pathog. 1990 Oct;9(4):267–273. doi: 10.1016/0882-4010(90)90015-i. [DOI] [PubMed] [Google Scholar]
  26. Welkos S. L., Holmes R. K. Regulation of toxinogenesis in Corynebacterium diphtheriae. I. Mutations in bacteriophage beta that alter the effects of iron on toxin production. J Virol. 1981 Mar;37(3):936–945. doi: 10.1128/jvi.37.3.936-945.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Infection and Immunity are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES