Inosine monophosphate synthase

The bifunctional Purinsyntheseprotein ( ATIC, PURH ) is the enzyme (IMP), the formylation and subsequent dehydration of AICAR catalyzes the final two steps in the de novo biosynthesis of inosine monophosphate. The individual enzyme functions are called AICAR formyl and IMP cyclohydrolase. PURH occurs in all living things, and the bi-functionality is preserved everywhere. Mutations in the ATIC gene of the people can PURH deficiency and this AICA Ribosurie, cause a rare genetic disease.

PURH activity is increased by phosphorylation; in a number of tumor cell lines is PURH before phosphorylated.

Catalyzed reactions

10 -formyl- THF ⇒ THF

AICAR is formylated to FAICAR.

⇔ H2O

FAICAR cyclizes with elimination of water to IMP.

The AICAR formyl - domain (amino acids 199-592 ) and the IMP cyclohydrolase domain ( 1-199 ) are 50 Å apart and retain their activity in separate expression.

Human Genome Organisation Transferase Formylation reaction Dehydration reaction Digital Object Identifier PubMed Central
36292
de