Back to Search
Start Over
Effects of limited aeration and of the ArcAB system on intermediary pyruvate catabolism in Escherichia coli
- Source :
- Journal of Bacteriology, 182, 4934-4940. American Society for Microbiology
- Publication Year :
- 2000
-
Abstract
- The capacity of Escherichia coli to adapt its catabolism to prevailing redox conditions resides mainly in three catabolic branch points involving (i) pyruvate formate-lyase (PFL) and the pyruvate dehydrogenase complex (PDHc), (ii) the exclusively fermentative enzymes and those of the Krebs cycle, and (iii) the alternative terminal cytochrome bd and cytochrome bo oxidases. A quantitative analysis of the relative catabolic fluxes through these pathways is presented for steady-state glucose-limited chemostat cultures with controlled oxygen availability ranging from full aerobiosis to complete anaerobiosis. Remarkably, PFL contributed significantly to the catabolic flux under microaerobic conditions and was found to be active simultaneously with PDHc and cytochrome bd oxidase-dependent respiration. The synthesis of PFL and cytochrome bd oxidase was found to be maximal in the lower microaerobic range but not in a ΔArcA mutant, and we conclude that the Arc system is more active with respect to regulation of these two positively regulated operons during microaerobiosis than during anaerobiosis.
- Subjects :
- Cytochrome
Physiology and Metabolism
Chemostat
medicine.disease_cause
Microbiology
chemistry.chemical_compound
Acetyltransferases
Pyruvic Acid
medicine
Escherichia coli
Molecular Biology
chemistry.chemical_classification
Oxidase test
biology
Catabolism
Escherichia coli Proteins
Membrane Proteins
Pyruvate dehydrogenase complex
Cytochrome b Group
NAD
Oxygen
Repressor Proteins
Enzyme
Glucose
Biochemistry
chemistry
Electron Transport Chain Complex Proteins
biology.protein
Cytochromes
Pyruvic acid
Oxidoreductases
Protein Kinases
Bacterial Outer Membrane Proteins
Subjects
Details
- ISSN :
- 00219193
- Volume :
- 182
- Database :
- OpenAIRE
- Journal :
- Journal of Bacteriology
- Accession number :
- edsair.doi.dedup.....d8677f4167ecbefa78510f15714042ae