Isolation and partial characterization of a corynebacteriophage beta, tox operator constitutive-like mutant lysogen of Corynebacterium diphtheriae

@article{Murphy1976IsolationAP,
  title={Isolation and partial characterization of a corynebacteriophage beta, tox operator constitutive-like mutant lysogen of Corynebacterium diphtheriae},
  author={James R. Murphy and John Skiver and Gordon E. McBride},
  journal={Journal of Virology},
  year={1976},
  volume={18},
  pages={235 - 244}
}
We have isolated and partially characterized a beta-phage mutant lysogen of Corynebacterium diphtheriae, C7(betatoxct1+), which is partially insensitive to iron inhibition of diphtheria toxin production. tox expression by C7(betatoxct1+) was found to be partially constitutive. In the presence of concentrations of iron that almost completely inhibit the expression of diphtheria toxin by the wild type, C7(beta), the level of toxin production by C7(betatoxct1+) was found to be at least 25 times… 

Isolation and characterization of extragenic suppressor strains of Corynebacterium diphtheriae

The isolation and characterization of two different nonsense suppressor strains of Corynebacterium diphtheriae C7 sup+(-)tox- are described. Appropriate lysogens of these strains with corynephage

Characterization of a defective diphtheria toxin repressor (dtxR) allele and analysis of dtxR transcription in wild-type and mutant strains of Corynebacterium diphtheriae

TLDR
Data demonstrate that C7(beta)hm723 expresses a mutant DtxR repressor protein that is severely defective in repressor activity.

Regulation of toxinogenesis in Corynebacterium diphtheriae. II. Genetic mapping of a tox regulatory mutation in bacteriophage beta

TLDR
Findings establish that the tox-201 regulatory site is closely linked to the end of the toxin structural gene corresponding to the origin of transcription, consistent with the hypothesis that tox- 201 defines a cis-dominant regulatory element, such as an operator, promoter, or attenuator, involved in control of toxinogenesis in C. diphtheriae C7(beta).

Regulation of toxinogenesis in Corynebacterium diphtheriae. I. Mutations in bacteriophage beta that alter the effects of iron on toxin production

TLDR
The characteristics of the tox-201 mutation suggest that it defines a regulatory locus of phage beta that is involved in control of toxinogenesis by iron in C. diphtheriae.

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

TLDR
A regulatory gene (dtxR) responsible for iron-dependent repression of the toxin and siderophore genes in Corynebacterium diphtheriae was cloned and characterized and Expression of the cloned dtxR determinant did not affect the phenotype of C. diphTheriae C7(beta).

Isolation from corynebacterium diphtheriae C7(beta) of bacterial mutants that produce toxin in medium with excess iron

TLDR
Findings show that the mutant strains are not phage mutants, but are bacterial host mutants, and that a host factor(s) is involved in the inhibition of toxin production by iron.

Regulation of toxinogenesis in Corynebacterium diphtheriae: mutations in the bacterial genome that alter the effects of iron on toxin production

TLDR
It is proposed that the altered regulation of toxinogenesis by iron in mutants was caused by the severe defects in their iron transport systems and exhibited a low-iron phenotype during growth under conditions that permitted wild-type C. diphtheriae C7(beta) to exhibit a high-iron phenotypes.

The diphtheria toxin structural gene.

  • J. Murphy
  • Biology, Chemistry
    Current topics in microbiology and immunology
  • 1985
TLDR
UCHIDA and coworkers (1973 a, b) described the isolation and characterization of a family ofβ-phage mutants which directed the synthesis of nontoxic serologically cross-reacting proteins that were related to diphtheria toxin.
...

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TLDR
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TLDR
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