[The substrate specificity of acyl-CoA synthetase from E. coli and the characterization of its purified preparation].
The substrate specificity of the acyl-CoA synthetase from E. coli was studied. The enzyme was purified by means of DEAE-Sephacel, hydroxyapatite, Sepharose 6B, and blue dextran-Sepharose 6B chromatography. The molecular weight of the purified enzyme was 47,000 estimated by Sephadex G-200 column chromatography. 45,000 was determined as the molecular weight by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified enzyme was quite unstable, however, the high concentration of potassium phosphate increased its stability. The chaotropic ion decreased the activity of purified enzyme, and the addition of the antichaotropic ions restored the activity to the original level. The purified enzyme activated the fatty acids with chain length of 6 to 18 carbon atoms, which was similar to the observations for the acyl-CoA synthetase in the crude extracts of E. coli. The purified enzyme also activated trans fatty acids at the same conversion rates as the corresponding cis isomers. Throughout the purification procedure, decanoyl-CoA synthetase activity was observed in the fractions which contained oleoyl-CoA synthetase activity.
D003066:Coenzyme A Ligases / Q000032:analysis / Q000302:isolation & purification*; D004926:Escherichia coli / Q000201:enzymology*; D005227:Fatty Acids / Q000378:metabolism; D008970:Molecular Weight; D013379:Substrate Specificity
D005227:Fatty Acids; D003066:Coenzyme A Ligases