Function
Decarboxylates OPET (5-oxo-pent-3-ene-1,2,5-tricarboxylic acid) into HHDD (2-hydroxy-hept-2,4-diene-1,7-dioate) and isomerizes it to OHED (2-oxo-hept-3-ene-1,7-dioate).
Sequence
MKGTIFAVALNHRSQLDAWQEAFQQSPIKAPPKTAVWFIKPRNTVIGCGEPIPFPQGENLLSGATVALIVGKTATKVREEDAAEYIAGYALANDVSLPEESFYRPAIKAKCRDGFCPIGETVALSNVDNLTIYTEINGRPADHWNTSDLQRNAAQLLSALSEFATLNPGDAILLGTPQARVEIQPGDRVRVLAEGFPPLENPVVDEREVTTRKSFPTLPHPHGTLFALGLNYADHASELEFKPPEEPLVFLKAPNTLTGDNQTSVRPNNIEYMHYEAELVVVIGKQARNVSEADAMDYVAGYTVCNDYAIRDYLENYYRPNLRVKSRDGLTPMLSTIVPKEAIPDPHNLTLRTFVNGELRQQGTTADLIFSVPFLIAYLSEFMTLNPGDMIATGTPKGLSDVGDEVVVEVEGVGRLVNRIVSEETAK