Jensen, Peter Ruhdal2; Michelsen, Ole3; Westerhoff, H. V.4
1 Department of Microbiology, Technical University of Denmark2 Systems Biotechnology, Department of Systems Biology, Technical University of Denmark3 Department of Systems Biology, Technical University of Denmark4 unknown
Strains carrying deletions in the atp genes, encoding the H+-ATPase, were unable to grow on nonfermentable substrates such as succinate, whereas with glucose as the substrate the growth rate of an atp deletion mutant was surprisingly high (some 75-80% of wild-type growth rate). The rate of glucose and oxygen consumption of these mutants was increased compared to the wild-type rates. In order to analyze the importance of the H+-ATPase at its physiological level, the cellular concentration of H+-ATPase was modulated around the wild-type level, using genetically manipulated strains. The control coefficient by the H+-ATPase with respect to growth rate and catabolic fluxes was measured. Control on growth rate was absent at the wildtype concentration of H+-ATPase, independent of whether the substrate for growth was glucose or succinate. Control by the H+-ATPase on the catabolic fluxes, including respiration, was negative at the wild-type H+-ATPase level. Moreover, the turnover number of the individual H+-ATPase enzymes increased as the H+-ATPase concentration was lowered. The negative control by the H+-ATPase on catabolism may thus be involved in a homeostatic control of ATP synthesis and, to some extent, explain the zero control by the H+-ATPase on E. coli growth rate.
Journal of Bioenergetics and Biomembranes, 1995, Vol 27, Issue 6, p. 543-554
Escherichia coli; Gene Deletion; Genes, Bacterial; Glucose; Kinetics; Operon; Oxygen Consumption; Proton-Translocating ATPases; Succinates; EC 126.96.36.199 Proton-Translocating ATPases; IY9XDZ35W2 Glucose; BIOPHYSICS; CELL; PROTON-TRANSLOCATING ATPASE; NUCLEOTIDE-SEQUENCE; OXIDATIVE-PHOSPHORYLATION; ADENOSINE-TRIPHOSPHATASE; SYNTHASE; OPERON; GENES; PROMOTERS; SUBUNIT; MUTATIONS; oxidative phosphorylation; respiration; ATP; fluxes; Metabolic Control Analysis; Oxidative phosphorylation; ATP GENE; BACTERIAL GROWTH RATE; CATABOLIC FLUX; GENETICS; MUTATION; OXIDATIVE PHOSPHORYLATION; OXYGEN CONSUMPTION; RESPIRATION; Facultatively Anaerobic Gram-Negative Rods Eubacteria Bacteria Microorganisms (Bacteria, Eubacteria, Microorganisms) - Enterobacteriaceae  Escherichia coli; ATP 56-65-5Q, 42530-29-0Q, 94587-45-8Q, 111839-44-2Q; ATPASE 9000-83-3; OXYGEN 7782-44-7; 02506, Cytology - Animal; 10012, Biochemistry - Gases; 10060, Biochemistry studies - General; 10062, Biochemistry studies - Nucleic acids, purines and pyrimidines; 10510, Biophysics - Bioenergetics: electron transport and oxidative phosphorylation; 10808, Enzymes - Physiological studies; 13003, Metabolism - Energy and respiratory metabolism; 16004, Respiratory system - Physiology and biochemistry; 31000, Physiology and biochemistry of bacteria; 31500, Genetics of bacteria and viruses; 36002, Medical and clinical microbiology - Bacteriology; Biochemistry and Molecular Biophysics; Bioenergetics; Cell Biology; Enzymology; Genetics; Infection; Metabolism; Physiology