A cis-trans isomerising activity of Escherichia coli. Isomerization from 2-(2-furyl)-3-cis-(5-nitro-2-furyl) acrylamide (furylfuramide) to its trans isomer.

The soluble enzyme fraction derived from Escherichia coli K-12 JE2100 cells was found to exhibit, in addition to Nadh- and NADPH-dependent reductase activities, NADH-dependent cis-trans isomerising activity toward 2-(2-furyl-3-(5-nitro-2-furyl)acrylamide leading to a specific change in geometrical configuration of the vinyl group at the 2-position from cis to trans but not in the reverse direction. This furylfuramide-isomerising action of bacteria was dicoumarol insensitive, and did not require glutathione for full activity. The particulate enzyme fraction derived from JE2100 cells, although it showed little reductase activity toward furylfuramide in the presence of either NADH or NADPH, revealed an isomerising activity in the presence of NADH.