Trifunctional purine biosynthetic protein adenosine-3

The trifunctional Purinsyntheseprotein ( GARS - AIRS - GART ) ( adenosine -3 ) is an enzyme in animals, in which three different enzymatic domains are fused to a protein: the Phosphoribosylamin -glycine ligase ( GARS ), the Phosphoribosylglycinamid formyl ( GART ) and the Phosphoribosylformylglycinamidin cyclo- ligase ( AIRS ). These activities are part of purine biosynthesis and come in all living things before: as an individual enzymes in prokaryotes and as partially bifunctional enzymes in yeast.

The domains of adenosine 3 are linearly arranged and catalyze the steps 2, 5, and 3 of zehnschrittigen biosynthesis of IMP. The human locus for the adenosine -3 gene is located on chromosome 21 GART, which may be the cause for increased Purinwerte Down syndrome.

Catalyzed reactions

GARS

ATP ADP Pi

The Phosphoribosylamin -glycine ligase domain facilitates the addition of glycine at 5 - Phosphoribosylamin ( PRA) to Glycinamidribonukleotid ( GAR ).

10 -formyl- THF THF

The Phosphoribosylglycinamid - formyltransferase ( GART ) catalyzes the formylation of Glycinamidribonukleotid ( GAR ) to Formylglycinamidribonukleotid ( FGAR ) by formyltetrahydrofolate.

AIRS

ATP ADP Pi H2O

The Phosphoribosylformylglycinamidin cyclo- ligase domain cyclized Formylglycinamidinribonukleotid ( FGAM ) to 5 Aminoimidazolribonukleotid (AIR).

Protein isoform Human Genome Organisation Formylation reaction Digital Object Identifier
29842
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