Catalyzes a salvage reaction resulting in the formation of IMP that is energically less costly than de novo synthesis. diphosphate + IMP = 5-phospho-alpha-D-ribose 1-diphosphate + hypoxanthine diphosphate + GMP = 5-phospho-alpha-D-ribose 1-diphosphate + guanine Purine metabolism; IMP biosynthesis via salvage pathway; IMP from hypoxanthine: step 1/1. Homodimer. Cells have increased resistant to purine analogs 8-aza-2,6-diaminopurine (8-ADP) and 2-methylpurine (2MP). No change in growth rate in HS (minimal) broth. Used for negative selection when transforming this organism. Belongs to the purine/pyrimidine phosphoribosyltransferase family. Archaeal HPRT subfamily.