A number of enzymes that catalyze the transfer of a phosphoryl group fromphosphoenolpyruvate (PEP) via a phospho-histidine intermediate have been shownto be structurally related [<cite idref="PUB00005010"/>, <cite idref="PUB00001868"/>, <cite idref="PUB00000317"/>, <cite idref="PUB00003750"/>]. All these enzymes share the same catalytic mechanism: they bind PEP andtransfer the phosphoryl group from it to a histidine residue. The sequencearound that residue is highly conserved. This domain is often found associated with the pyruvate phosphate dikinase, PEP/pyruvate-binding domain (<db_xref db="INTERPRO" dbkey="IPR002192"/>) at its N terminus and the PEP-utilizing enzyme mobile domain.