Protein Family Models

This enzyme (Swiss:O27099) is may catalyse the cyclization 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 alpha-beta-beta-alpha core structure. The two antiparallel beta-sheets pack against each other and are covered by alpha-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 [1]. [1]. 12012346. Crystal structure of Methanobacterium thermoautotrophicum conserved protein MTH1020 reveals an NTN-hydrolase fold. Saridakis V, Christendat D, Thygesen A, Arrowsmith CH, Edwards AM, Pai EF;. Proteins 2002;48:141-143. (from Pfam)

Date:

2024-10-16

IMP (inosine monophosphate) cyclohydrolase catalyzes the cyclization of 5-formylamidoimidazole-4-carboxamide ribonucleotide to IMP

Date:

2020-05-19