Tags

Type your tag names separated by a space and hit enter

Reversible inactivation of the isocitrate dehydrogenase of Escherichia coli ML308 during growth on acetate.
J Gen Microbiol. 1975 Mar; 87(1):37-51.JG

Abstract

During aerobic growth of Escherichia coli ML308 on acetate as sole carbon source, the apparent synthesis of isocitrate dehydrogenase was repressed relative to cultures on other carbon sources, such as glucose, which do not employ the glyoxylate bypass as an anaplerotic sequence. When cells were removed from an acetate medium, or when compounds were added which made the operation of the glyoxylate bypass unnecessary, the activity of isocitrate dehydrogenase rapidly increased 3- to 4-fold but fell again on restoration to an acetate medium. Changes in activity were rapid and, furthermore, could be demonstrated in the absence of protein synthesis. It is thus improbable that the mechanism involved degradation or de novo synthesis of the enzyme protein. Oxaloacetate and glyoxylate showed concerted inhibition of isocitrate dehydrogenase which could be relieved by dialysis. Because extracts of low enzyme activity, derived from acetate-metabolizing cells, could not be stimulated by dialysis or by addition of a wide range of metabolites, it is unlikely that low molecular weight, freely dissociable effectors were responsible for stimulation or inhibition of activity. Control of isocitrate dehydrogenase permitted the efficient utilization of acetate as sole source of carbon and energy but perserved the capacity of the cell to respond rapidly to an improvement in nutritional conditions. A limited survey showed that the mechanism is common but not universal among strains of E. coli and occurs in at least one strain each of Klebsiella aerogenes, Salmonella typhimurium and Serratia marcescens.

Authors

No affiliation info availableNo affiliation info available

Pub Type(s)

Comparative Study
Journal Article

Language

eng

PubMed ID

1094097

Citation

Bennett, P M., and W H. Holms. "Reversible Inactivation of the Isocitrate Dehydrogenase of Escherichia Coli ML308 During Growth On Acetate." Journal of General Microbiology, vol. 87, no. 1, 1975, pp. 37-51.
Bennett PM, Holms WH. Reversible inactivation of the isocitrate dehydrogenase of Escherichia coli ML308 during growth on acetate. J Gen Microbiol. 1975;87(1):37-51.
Bennett, P. M., & Holms, W. H. (1975). Reversible inactivation of the isocitrate dehydrogenase of Escherichia coli ML308 during growth on acetate. Journal of General Microbiology, 87(1), 37-51.
Bennett PM, Holms WH. Reversible Inactivation of the Isocitrate Dehydrogenase of Escherichia Coli ML308 During Growth On Acetate. J Gen Microbiol. 1975;87(1):37-51. PubMed PMID: 1094097.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Reversible inactivation of the isocitrate dehydrogenase of Escherichia coli ML308 during growth on acetate. AU - Bennett,P M, AU - Holms,W H, PY - 1975/3/1/pubmed PY - 1975/3/1/medline PY - 1975/3/1/entrez SP - 37 EP - 51 JF - Journal of general microbiology JO - J Gen Microbiol VL - 87 IS - 1 N2 - During aerobic growth of Escherichia coli ML308 on acetate as sole carbon source, the apparent synthesis of isocitrate dehydrogenase was repressed relative to cultures on other carbon sources, such as glucose, which do not employ the glyoxylate bypass as an anaplerotic sequence. When cells were removed from an acetate medium, or when compounds were added which made the operation of the glyoxylate bypass unnecessary, the activity of isocitrate dehydrogenase rapidly increased 3- to 4-fold but fell again on restoration to an acetate medium. Changes in activity were rapid and, furthermore, could be demonstrated in the absence of protein synthesis. It is thus improbable that the mechanism involved degradation or de novo synthesis of the enzyme protein. Oxaloacetate and glyoxylate showed concerted inhibition of isocitrate dehydrogenase which could be relieved by dialysis. Because extracts of low enzyme activity, derived from acetate-metabolizing cells, could not be stimulated by dialysis or by addition of a wide range of metabolites, it is unlikely that low molecular weight, freely dissociable effectors were responsible for stimulation or inhibition of activity. Control of isocitrate dehydrogenase permitted the efficient utilization of acetate as sole source of carbon and energy but perserved the capacity of the cell to respond rapidly to an improvement in nutritional conditions. A limited survey showed that the mechanism is common but not universal among strains of E. coli and occurs in at least one strain each of Klebsiella aerogenes, Salmonella typhimurium and Serratia marcescens. SN - 0022-1287 UR - https://www.unboundmedicine.com/medline/citation/1094097/Reversible_inactivation_of_the_isocitrate_dehydrogenase_of_Escherichia_coli_ML308_during_growth_on_acetate_ DB - PRIME DP - Unbound Medicine ER -