| Primary Identifier | IPR010191 | Type | Family |
| Short Name | IMP_cyclohydrolase |
| description | This entry represents IMP cyclohydrolase, which catalyses the cyclisation of 5-formylamidoimidazole-4-carboxamide ribonucleotide to inosine monophosphate (IMP), a reaction which is important in de novo purine biosynthesis in archaeal species []. This single domain protein is arranged to form an overall fold that consists of a four-layered α-β-beta-alpha core structure. The two antiparallel β-sheets pack against each other and are covered by α-helices on one face of the molecule. The protein is structurally similar to members of the N-terminal nucleophile (NTN) hydrolase superfamily. A deep pocket was in fact found on the surface of IMP cyclohydrolase in a position equivalent to that of active sites of NTN-hydrolases, but an N-terminal nucleophile could not be found. Therefore, it is thought that this enzyme is structurally but not functionally similar to members of the NTN-hydrolase family [].In bacteria this step is catalysed by a bifunctional enzyme (purH). |
