ACT_SITE 10; /evidence="ECO:0000250"; ACT_SITE 13; /evidence="ECO:0000250"; ACT_SITE 66; /note="Schiff-base intermediate with substrate; via pyruvic acid"; /evidence="ECO:0000250"; ACT_SITE 80; /note="Proton donor; for catalytic activity"; /evidence="ECO:0000250"; ACT_SITE 237; /note="Proton acceptor; for processing activity"; /evidence="ECO:0000250"; ACT_SITE 251; /note="Proton acceptor; for processing activity"; /evidence="ECO:0000250"