ACT_SITE 73; /note="Charge relay system"; /evidence="ECO:0000255|PROSITE-ProRule:PRU00274"; ACT_SITE 120; /note="Charge relay system"; /evidence="ECO:0000255|PROSITE-ProRule:PRU00274"; ACT_SITE 218; /note="Charge relay system"; /evidence="ECO:0000255|PROSITE-ProRule:PRU00274"