Type 1 glutamine amidotransferase (GATase1)-like domain found in at the C-terminal of several large catalases
Type 1 glutamine amidotransferase (GATase1)-like domain found in at the C-terminal of several large catalases. Catalase catalyzes the dismutation of hydrogen peroxide (H2O2) to water and oxygen. This group includes the large catalases: Neurospora crassa Catalase-1 and Catalase-3 and, Escherichia coli HP-II. This GATase1-like domain has an essential role in HP-II catalase activity. However, it lacks enzymatic activity and the catalytic triad typical of GATase1 domains. Catalase-1 and -3 are homotetrameric, HP-II is homohexameric. It has been proposed that this domain may facilitate the folding and oligomerization process. The interface between this GATase1-like domain of HP-II and the core of the subunit forms part of a channel which provides access to the deeply buried catalase active sites of HPII. Catalase-1 is associated with non-growing cells; Catalase-3 is associated with growing conditions. HP-II is produced in stationary phase. Catalase-1 is induced by ethanol and heat shock. Catalase-3 is induced under stress conditions such a hydrogen peroxide, paraquat, cadmium, heat shock, uric acid and nitrate treatment.