title: Inhibitory effect of long chain fatty acyl CoAs on RNA polymerase from Escherichia coli.
abstract: RNA polymerase from Escherichia coli was inhibited by long chain fatty acyl CoAs, such as myristoyl CoA (Ki = 17.2 microM), palmitoyl CoA (Ki = 8.9 microM), oleoyl CoA (Ki = 5.5 microM), and stearoyl CoA (Ki = 0.94 microM). The inhibition by these CoA thioesters was non-competitive against nucleoside triphosphates. Short chain fatty acyl CoAs, such as acetyl CoA, propionyl CoA, acetoacetyl CoA, butyryl CoA, and decanoyl CoA, failed to inhibit RNA polymerase. CoA, Na-myristate, Na-palmitate, Na-oleate, Na-stearate, palmitoyl carnitine, and carnitine did not inhibit the enzyme. The inhibition of RNA polymerase by long chain fatty acyl CoAs was competitive against template DNA.
mesh_terms: D000214:Acyl Coenzyme A / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D012321:DNA-Directed RNA Polymerases / Q000037:antagonists & inhibitors*; D004926:Escherichia coli / Q000201:enzymology*
chemical_list: D000214:Acyl Coenzyme A; D012321:DNA-Directed RNA Polymerases