Studies on cis-trans isomerization of nitrofuran derivatives by bacterial nitroreductases.
cis-trans Isomerization of 3-(5-nitro-2-furyl)-2-(2-furyl)-acrylamide(AF-2) using Escherichia coli B/r and its two 5-nitro-2-furaldehyde semicarbazone (nitrofurazone)-resistant mutants was investigated. The isomerizing activity was detected in all three strains and markedly increased with acquiring resistance to nitro-furazone in intact cells and cell free extracts. Two distinct isomerases, nicotinamide adenine dinucleotide phosphate(NADPH)-dependent one with high activity and NAD(P)H-dependent with low activity were separated by Sephadex G-100 and Sepharose 4B columns. Both enzyme activities agreed with the nitrofurazone-reducing activity due to O2-sensitive nitroreductase as reported previously. Another nitroreductase, O2-insensitive one, was unable to isomerize cis AF-2 to trans form. These results suggest that bacterial cis-trans isomerases are not O2-insensitive nitroreductase, but O2-sensitive ones.
D001419:Bacteria / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology; D007535:Isomerases / Q000032:analysis; D007536:Isomerism; D009154:Mutation; D009249:NADP / Q000494:pharmacology; D009581:Nitrofurans / Q000378:metabolism*; D009601:Nitroreductases; D010088:Oxidoreductases / Q000378:metabolism*; D010100:Oxygen / Q000494:pharmacology
D009581:Nitrofurans; D009249:NADP; D010088:Oxidoreductases; D009601:Nitroreductases; D007535:Isomerases; D010100:Oxygen