Developing a Collection of Immobilized Nucleoside Phosphorylases for the Preparation of Nucleoside Analogues: Enzymatic Synthesis of Arabinosyladenine and 2′,3′-Dideoxyinosin

IMMACOLATA SERRA; DANIELA UBIALI; JURE PISKUR; STIG CHRISTOFFERSEN; ELIZABETH LEWKOWICZ; ADOLFO IRIBARREN; ALESSANDRA ALBERTINI; MARCO TERRENI

ChemPlusChem

Wiley

Año: 2012 vol. 78 p. 157 - 165

2192-6506

The use of nucleoside phosphorylases (NPs; EC 2.4.2.n) repre-sents a convenient alternative to the chemical route for the synthesis of natural and modified nucleosides. We purified four recombinantly expressed nucleoside phosphorylases from the bacterial pathogensCitrobacter koseri, Clostridium perfringens, andStreptococcus pyogenes(CkPNPI,CkPNPII,CpUP,SpUP) and their substrate specificity was investigated towards either natu-ral pyrimidine or purine nucleosides and some analogues, namely, arabinosyladenine (araA) and 2’,3’-dideoxyinosine (ddI). A 2–3% activity towards these latter compounds (compared to the natural substrates) was observed. Enzyme activities were compared to the specificities obtained for the enzymes pyrimi-dine nucleoside phosphorylase fromBacillus subtilis(BsPyNP) and purine nucleoside phosphorylase fromAeromonas hydro-phila(AhPNPII) previously reported by some of the authors. The enzymes displaying the suitable specificity for the synthe-sis of araA and ddI were immobilized on aldehyde–agarose. The immobilized preparations were highly stable at alkaline pH and in the presence of methanol or acetonitrile as cosolvent. They were used in the synthesis of araA and ddI by a one-pot, bienzymatic transglycosylation achieving 74 and 44% conver-sion, respectively