<p>Urease (urea amidohydrolase, <db_xref db="EC" dbkey="3.5.1.5"/>) catalyses the hydrolysis of urea to form ammonia and carbamate. The subunit composition of urease from different sources varies [<cite idref="PUB00010725"/>], but each holoenzyme consists of four structural domains [<cite idref="PUB00005206"/>]: three structural domains and a nickel-binding catalytic domain common to amidohydrolases [<cite idref="PUB00004994"/>]. Urease is unique among nickel metalloenzymes in that it catalyses a hydrolysis rather than a redox reaction. In <taxon tax_id="28451">Klebsiella aerogenes</taxon>, the domains are found in an alpha subunit (with the C-terminal two-thirds representing the catalytic domain and the N-terminal one-third representing one of the structural domains; <db_xref db="INTERPRO" dbkey="IPR008295"/>), a beta subunit (<db_xref db="INTERPRO" dbkey="IPR008222"/>), and a gamma subunit (<db_xref db="INTERPRO" dbkey="IPR012010"/>). In <taxon tax_id="210">Helicobacter pylori</taxon>, the gamma and beta domains are fused and represent this alpha subunit entry. The catalytic subunit (called beta or B) has the same organisation as the K. aerogenes alpha subunit. Jack bean (<taxon tax_id="3823">Canavalia ensiformis</taxon>) urease has a fused gamma-beta-alpha organisation.</p><p>This group represents the fused gamma/beta organisation typified by the H. pylori alpha subunit.</p> Urease, gamma/beta subunit