Citrate synthase and 2-methylcitrate synthase: structural, functional and evolutionary relationships.
Following the complete sequencing of the Escherichia coli genome, it has been shown that the proposed second citrate synthase of this organism, recently described by the authors, is in fact a 2-methylcitrate synthase that possesses citrate synthase activity as a minor component. Whereas the hexameric citrate synthase is constitutively produced, the 2-methylcitrate synthase is induced during growth on propionate, and the catabolism of propionate to succinate and pyruvate via 2-methylcitrate is proposed. The citrate synthases of the psychrotolerant eubacterium DS2-3R, and of the thermophilic archaea Thermoplasma acidophilum and Pyrococcus furiosus, are approximately 40% identical in sequence to the Escherichia coli 2-methylcitrate synthase and also possess 2-methylcitrate synthase activity. The data are discussed with respect to the structure, function and evolution of citrate synthase and 2-methylcitrate synthase.
Gerike
Ursula
U
Centre for Extremophile Research, Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
Hough
David W
DW
Centre for Extremophile Research, Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
Russell
Nicholas J
NJ
Department of Biological Sciences, Wye College, University of London, Wye, Kent TN25 5AH, UK.
Dyall-Smith
Michael L
ML
Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria 3052, Australia.
Danson
Michael J
MJ
Centre for Extremophile Research, Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
D001426:Bacterial Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D002950:Citrate (si)-Synthase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000254:growth & development; D005798:Genes, Bacterial; D007652:Oxo-Acid-Lyases / Q000032:analysis / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
D001426:Bacterial Proteins; D002950:Citrate (si)-Synthase; C112399:2-methylcitrate synthase; D007652:Oxo-Acid-Lyases