IMP is an intermediate in de novo biosynthesis of purine nucleotides (Figure 22.4) and is found in several purine nucleotide metabolic pathways.
IMP is a branch point between synthesis of GMP and AMP (Figure 22.6). IMP is acted upon by adenylosuccinate synthetase in AMP biosynthesis and by IMP dehydrogenase in GMP biosynthesis.
In purine catabolism, AMP can be made into IMP by action of the enzyme AMP deaminase (Figure 22.7).
IMP can also be made from PRPP and hypoxanthine by the enzyme HGPRT (Figure 22.9).