A Cyanobacterial Gene Encoding a Protein with Extensive Homology to Mammalian Phosphoribosylpyrophosphate Synthetase

Phosphoribosylpyrophosphate (PRibPP) is the primary precursor in the biosynthesis of purine and pyrimidine nucleotides. The synthesis of PRibPP is catalysed by a ubiquitous PRibPP synthetase in many organisms. We provide evidence that a cyanobacterium, Synechococcus sp., has a gene encoding a protein with striking homology to mammalian PRibPP synthetases.