Molecular cloning and nucleotide sequence of purine nucleoside phosphorylase and uridine phosphorylase genes from Klebsiella sp.

Klebsiella sp. LF 1202 was isolated as a bacterium that can assimilate adenosine as a sole source of carbon and nitrogen [F. Ling et al., Agric. Biol. Chem., 55, 573-575 (1991)] from a soil sample. Both the purine nucleoside phosphorylase (PNPase) and uridine phosphorylase (UPase) of this bacterium were induced simultaneously when the bacterium was cultured in a medium containing adenosine or uridine as a sole source of carbon and nitrogen. This induction profile is different from that of Escherichia coli. Here we cloned and sequenced the gene corresponding to each enzyme. The open reading frame (ORF) of the PNPase gene consisted of 717 bp that encoded a polypeptide of 239 amino acids with a molecular weight of 26,198. The ORF of the UPase gene consisted of 834 bp that encoded a polypeptide of 278 amino acids with a molecular weight of 28,912.