Abstract
A homolog of the Corynebacterium diphtheriae dtxR gene was isolated from Brevibacterium lactofermentum. The product of the B. lactofermentum dtxR gene was immunoreactive with polyclonal anti-DtxR antibodies and functioned as an iron-activated repressor capable of regulating the expression of beta-galactosidase from a diphtheria tox promoter/operator transcriptional fusion in recombinant Escherichia coli. The extents of induction by increasing concentrations of the chelator 2,2'-dipyridyl were identical in cells expressing DtxR from either C. diphtheriae or B. lactofermentum.
Full Text
The Full Text of this article is available as a PDF (216.8 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Boyd J. M., Hall K. C., Murphy J. R. DNA sequences and characterization of dtxR alleles from Corynebacterium diphtheriae PW8(-), 1030(-), and C7hm723(-). J Bacteriol. 1992 Feb;174(4):1268–1272. doi: 10.1128/jb.174.4.1268-1272.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Günter K., Toupet C., Schupp T. Characterization of an iron-regulated promoter involved in desferrioxamine B synthesis in Streptomyces pilosus: repressor-binding site and homology to the diphtheria toxin gene promoter. J Bacteriol. 1993 Jun;175(11):3295–3302. doi: 10.1128/jb.175.11.3295-3302.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmitt M. P., Holmes R. K. Characterization of a defective diphtheria toxin repressor (dtxR) allele and analysis of dtxR transcription in wild-type and mutant strains of Corynebacterium diphtheriae. Infect Immun. 1991 Nov;59(11):3903–3908. doi: 10.1128/iai.59.11.3903-3908.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmitt M. P., Holmes R. K. Cloning, sequence, and footprint analysis of two promoter/operators from Corynebacterium diphtheriae that are regulated by the diphtheria toxin repressor (DtxR) and iron. J Bacteriol. 1994 Feb;176(4):1141–1149. doi: 10.1128/jb.176.4.1141-1149.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmitt M. P., Holmes R. K. Iron-dependent regulation of diphtheria toxin and siderophore expression by the cloned Corynebacterium diphtheriae repressor gene dtxR in C. diphtheriae C7 strains. Infect Immun. 1991 Jun;59(6):1899–1904. doi: 10.1128/iai.59.6.1899-1904.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tao X., Boyd J., Murphy J. R. Specific binding of the diphtheria tox regulatory element DtxR to the tox operator requires divalent heavy metal ions and a 9-base-pair interrupted palindromic sequence. Proc Natl Acad Sci U S A. 1992 Jul 1;89(13):5897–5901. doi: 10.1073/pnas.89.13.5897. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tao X., Murphy J. R. Determination of the minimal essential nucleotide sequence for diphtheria tox repressor binding by in vitro affinity selection. Proc Natl Acad Sci U S A. 1994 Sep 27;91(20):9646–9650. doi: 10.1073/pnas.91.20.9646. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tao X., Schiering N., Zeng H. Y., Ringe D., Murphy J. R. Iron, DtxR, and the regulation of diphtheria toxin expression. Mol Microbiol. 1994 Oct;14(2):191–197. doi: 10.1111/j.1365-2958.1994.tb01280.x. [DOI] [PubMed] [Google Scholar]
- Wang Z., Schmitt M. P., Holmes R. K. Characterization of mutations that inactivate the diphtheria toxin repressor gene (dtxR). Infect Immun. 1994 May;62(5):1600–1608. doi: 10.1128/iai.62.5.1600-1608.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]