dihydroisopentenyldehydrorhodopin + A => isopentenyldehydrorhodopin + AH2
dihydroisopentenyldehydrorhodopin + a => isopentenyldehydrorhodopin + ah2
dihydroisopentenyldehydrorhodopin + A => isopentenyldehydrorhodopin + AH2
dihydroisopentenyldehydrorhodopin + a => isopentenyldehydrorhodopin + ah2