59885-96-0Relevant articles and documents
Site-Selective ribosylation of fluorescent nucleobase analogs using purine-Nucleoside phosphorylase as a catalyst: effects of point mutations
Stachelska-Wierzchowska, Alicja,Wierzchowski, Jacek,Bzowska, Agnieszka,Wielgus-Kutrowska, Beata
, (2016)
Enzymatic ribosylation of fluorescent 8-azapurine derivatives, like 8-azaguanine and 2,6-diamino-8-azapurine, with purine-nucleoside phosphorylase (PNP) as a catalyst, leads to N9, N8, and N7-ribosides. The final proportion of the products may be modulated by point mutations in the enzyme active site. As an example, ribosylation of the latter substrate by wild-type calf PNP gives N7- And N8-ribosides, while the N243D mutant directs the ribosyl substitution at N9- And N7-positions. The same mutant allows synthesis of the fluorescent N7-β-D-ribosyl-8-azaguanine. The mutated form of the E. coli PNP, D204N, can be utilized to obtain non-typical ribosides of 8-azaadenine and 2,6-diamino-8-azapurine as well. The N7- And N8-ribosides of the 8-azapurines can be analytically useful, as illustrated by N7-β-D-ribosyl-2,6-diamino-8-azapurine, which is a good fluorogenic substrate for mammalian forms of PNP, including human blood PNP, while the N8-riboside is selective to the E. coli enzyme.