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

Journal of Bacteriology
S J CryzR K Holmes

Abstract

Mutants of Corynebacterium diphtheriae C7(beta) that are resistant to the inhibitory effects of iron on toxinogenesis were identified by their ability to form colonies surrounded by toxin-antitoxin halos on agar medium containing both antitoxin and a high concentration of iron. Chromosomal mutations were essential for the altered phenotypes of four independently isolated mutant strains. During growth in deferrated liquid medium containing various amounts of added iron, these mutants differed from wild-type C. diphtheriae C7(beta) in several ways. Their growth rates were slower under low-iron conditions and were stimulated to various degrees under high-iron conditions. The concentrations of iron at which optimal toxin production occurred were higher for the mutants than for wild-type C. diphtheriae C7(beta). Toxin production by the mutants during growth in low-iron medium occurred throughout the period of exponential growth at nearly constant rates that were proportional to the bacterial growth rates. In contrast, toxin production by wild-type C. diphtheriae C7(beta) in similar low-iron cultures occurred predominantly during the late exponential phase, when iron was a growth-limiting nutrient. Additional studies demonstrated tha...Continue Reading

References

Jan 1, 1977·Annual Review of Biochemistry·A M Pappenheimer
Jun 1, 1970·Journal of Virology·R K Holmes, L Barksdale
Jan 1, 1974·Annual Review of Microbiology·L Barksdale, S B Arden
Dec 1, 1970·Bacteriological Reviews·L Barksdale
Jun 1, 1969·Journal of Virology·R K Holmes, L Barksdale
Sep 1, 1971·Nature: New Biology·T UchidaA M Pappenheimer
Feb 1, 1954·Journal of Bacteriology·W L BARDSDALE, A M PAPPENHEIMER
Oct 1, 1955·Proceedings of the Society for Experimental Biology and Medicine·E I PARSONS
Nov 21, 1960·Annals of the New York Academy of Sciences·L BARKSDALEK HORIBATA
Apr 1, 1961·Journal of Bacteriology·L BARKSDALER RIVERA
Jan 1, 1949·Acta Pathologica Et Microbiologica Scandinavica·O OUCHTERLONY
Mar 13, 1948·British Medical Journal·S D ELEK

❮ Previous
Next ❯

Citations

Jan 1, 1985·Critical Reviews in Microbiology·J W Foster, D M Kinney
Feb 5, 2000·The Journal of Infectious Diseases·R K Holmes
Jan 1, 1985·Molecular & General Genetics : MGG·S SchäfferV Braun
Nov 1, 1993·FEMS Microbiology Reviews·K G Wooldridge, P H Williams
Feb 27, 2007·Journal of Bacteriology·Carey A Kunkle, Michael P Schmitt
Jan 1, 1991·Journal of Bacteriology·T M Staggs, R D Perry
Sep 1, 1988·Infection and Immunity·S P Tai, R K Holmes

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.