Lack of Enhanced Purine Biosynthesis in HGPRT-and Lesch-Nyhan Cells

Abstract

The rate of de novo purine biosynthesis was measured in a series of hypoxanthine guanine phosphoribosyl transferase deficient (HGPRT^-) cells from a variety of sources, including human Lesch-Nyhan cells. Under optimum growth conditions, no enhanced purine biosynthesis was detected (in contrast to previous reports). An ‘elevated’ level of de novo purine biosynthesis could be detected in mutants following starvation for glutamine. However, this was the result of depression of purine biosynthesis in normal cells, with a resulting artifactual overproduction in mutants.