RT Journal Article SR Electronic(1) A1 Jones, Peter W. A1 Turner, John M.YR 1984 T1 A Model for the Common Control of Enzymes of Ethanolamine Catabolism in Escherichia coli JF Microbiology, VO 130 IS 4 SP 849 OP 860 DO https://doi.org/10.1099/00221287-130-4-849 PB Microbiology Society, SN 1465-2080, AB By varying the composition of the growth medium and the genotype of the bacterial strain, five isoenzymes of CoA-dependent aldehyde dehydrogenase could be detected in Escherichia coli. Two isoenzymes (A, mol. wt 520000; and B, mol. wt 370000) were produced only in the presence of ethanolamine and vitamin (or coenzyme) B12 (‘inducible isoenzyme’), whereas the other three isoenzymes (C, mol. wt 900000; D, mol. wt 120000; and E, mol. wt 720000) were produced only in the absence of ethanolamine and vitamin B12 (‘repressible isoenzymes’). Partial purification and characterization of these isoenzymes revealed strong similarities, with respect to pH optima and substrate affinities, between isoenzymes within either of the two classes, but significant differences between the two classes. Mutant studies demonstrated that the relationships between the isoenzymes and between CoA-dependent aldehyde dehydrogenase and ethanolamine ammonia-lyase are both structural and regulatory in nature, and a two-operon model is proposed to account for the common control of the enzymes of ethanolamine catabolism in E. coli., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-130-4-849