. "Catalysis of the reaction: isopentenyl diphosphate = dimethylallyl diphosphate." . . "isopentenyl-diphosphate delta-isomerase activity" . "IPP isomerase activity" . "isopentenyl-diphosphate D-isomerase activity" . "isopentenyl-diphosphate delta3-delta2-isomerase activity" . "isopentenylpyrophosphate delta-isomerase activity" . "isopentenylpyrophosphate isomerase activity" . "methylbutenylpyrophosphate isomerase activity" . . .