<p>This group contains metallopeptidases belonging to MEROPS peptidase family M20 (clan MH), subfamilies M20A and M20B; many are classified as unassigned peptidases or non-peptidase homologues.</p><p>In addition to the metallopeptidases this group of sequences contain a variety of other protein families from the archaea, bacteria and eukaryota that hydrolyse substrates that share a common structure and are dependent on cobalt or zinc for their activity [<cite idref="PUB00014889"/>]. They include:</p><p> <ul><li>glutamate acetyltransferase (<db_xref db="EC" dbkey="2.3.1.35"/>)</li><li>acetylornithine deacetylase (argE) (<db_xref db="EC" dbkey="3.5.1.16"/>)</li><li>leucoanthocyanidin dioxygenase </li><li>succinyldiaminopimelate desuccinylase (dapE) (<db_xref db="EC" dbkey="3.5.1.18"/>)</li><li>aminoacylase-1 (ACY1), carboxypeptidase G2 (CPG2) (<db_xref db="EC" dbkey="3.4.17.11"/>)</li><li>vacuolar carboxypeptidase S (yscS) (<db_xref db="EC" dbkey="3.4.17.4"/>)</li><li>peptidase T (<db_xref db="EC" dbkey="3.4.11"/>)</li><li>Xaa-His dipeptidase (<db_xref db="EC" dbkey="3.4.13.3"/>).</li> </ul> </p> ArgE/DapE/ACY1/CPG2/YscS, conserved site