ACT_SITE 53; /note="Charge relay system"; /evidence="ECO:0000250|UniProtKB:P15367"; ACT_SITE 92; /note="Charge relay system"; /evidence="ECO:0000250|UniProtKB:P15367"; ACT_SITE 133; /note="Charge relay system"; /evidence="ECO:0000250|UniProtKB:P15367"