ACT_SITE 586; /note="Charge relay system"; /evidence="ECO:0000250"; ACT_SITE 717; /note="Charge relay system"; /evidence="ECO:0000250"; ACT_SITE 793; /note="Charge relay system"; /evidence="ECO:0000250"; ACT_SITE 892; /note="Proton donor"; /evidence="ECO:0000255|PROSITE-ProRule:PRU10003"