59-14-3Relevant articles and documents
Thermodynamic Reaction Control of Nucleoside Phosphorolysis
Kaspar, Felix,Giessmann, Robert T.,Neubauer, Peter,Wagner, Anke,Gimpel, Matthias
supporting information, p. 867 - 876 (2020/01/24)
Nucleoside analogs represent a class of important drugs for cancer and antiviral treatments. Nucleoside phosphorylases (NPases) catalyze the phosphorolysis of nucleosides and are widely employed for the synthesis of pentose-1-phosphates and nucleoside analogs, which are difficult to access via conventional synthetic methods. However, for the vast majority of nucleosides, it has been observed that either no or incomplete conversion of the starting materials is achieved in NPase-catalyzed reactions. For some substrates, it has been shown that these reactions are reversible equilibrium reactions that adhere to the law of mass action. In this contribution, we broadly demonstrate that nucleoside phosphorolysis is a thermodynamically controlled endothermic reaction that proceeds to a reaction equilibrium dictated by the substrate-specific equilibrium constant of phosphorolysis, irrespective of the type or amount of NPase used, as shown by several examples. Furthermore, we explored the temperature-dependency of nucleoside phosphorolysis equilibrium states and provide the apparent transformed reaction enthalpy and apparent transformed reaction entropy for 24 nucleosides, confirming that these conversions are thermodynamically controlled endothermic reactions. This data allows calculation of the Gibbs free energy and, consequently, the equilibrium constant of phosphorolysis at any given reaction temperature. Overall, our investigations revealed that pyrimidine nucleosides are generally more susceptible to phosphorolysis than purine nucleosides. The data disclosed in this work allow the accurate prediction of phosphorolysis or transglycosylation yields for a range of pyrimidine and purine nucleosides and thus serve to empower further research in the field of nucleoside biocatalysis. (Figure presented.).
Biotransformation of halogenated nucleosides by immobilized Lactobacillus animalis 2′-N-deoxyribosyltransferase
Britos, Claudia N.,Lapponi, María José,Cappa, Valeria A.,Rivero, Cintia W.,Trelles, Jorge A.
, p. 91 - 96 (2016/05/10)
An immobilized biocatalyst with 2′-N-deoxyribosyltransferase (NDT) activity, Lactobacillus animalis NDT (LaNDT), was developed from cell free extracts. LaNDT was purified, characterized and then immobilized by ionic interaction. Different process parameters were optimized, resulting in an active derivative (2.6 U/g) able to obtain 1.75 mg/g of 5-fluorouracil-2′-deoxyriboside, an antimetabolite known as floxuridine, used in gastrointestinal cancer treatment. Furthermore, immobilized LaNDT was satisfactorily used to obtain at short reaction times other halogenated pyrimidine and purine 2′-deoxynucleosides such as 6-chloropurine-2′-deoxyriboside (4.9 U/g), 6-bromopurine-2′-deoxyriboside (4.3 U/g), 6-chloro-2-fluoropurine-2′-deoxyriboside (5.4 U/g), 5-bromo-2′-deoxyuridine (2.8 U/g) and 5-chloro-2′-deoxyuridine (1.8 U/g) compounds of pharmaceutical interest in antiviral or antitumor treatments. Besides, increasing the biocatalyst amount 8 times per volume unit allowed obtaining a 5-fold improvement in floxuridine biotransformation. The developed biocatalyst proved to be effective for the biosynthesis of a wide spectrum of nucleoside analogues by employing an economical, simple and environmentally friendly methodology.
A comparison between immobilized pyrimidine nucleoside phosphorylase from Bacillus subtilis and thymidine phosphorylase from Escherichia coli in the synthesis of 5-substituted pyrimidine 2′-deoxyribonucleosides
Serra, Immacolata,Bavaro, Teodora,Cecchini, Davide A.,Daly, Simona,Albertini, Alessandra M.,Terreni, Marco,Ubiali, Daniela
, p. 16 - 22 (2013/10/22)
Pyrimidine nucleoside phosphorylase from Bacillus subtilis (BsPyNP, E.C. 2.4.2.3) and thymidine phosphorylase from Escherichia coli (EcTP, E.C. 2.4.2.4) were used, as immobilized enzymes, in the synthesis of 5-halogenated pyrimidine 2′-deoxyribonucleosides (14-18) by transglycosylation in fully aqueous medium. From the comparative study of the two biocatalysts, no remarkable differences emerged about their substrate specificity, bioconversion yield, stability in organic cosolvents (DMF and MeCN). Moreover, both biocatalysts could be recycled for at least 5 times with no loss of the productivity. Both enzymes do not accept arabinonucleosides and 2′,3′- dideoxynucleosides as substrates, whereas they catalyze bioconversions involving 5′-deoxyribonucleosides and 5-halogenated uracils. The synthesis of compounds 14-18 proceeded at a similar conversion (33-68% for BsPyNP and 25-62% for EcTP, respectively). Immobilization was found to exert, for both the biocatalysts, a dramatic enhancement of stability upon incubation in MeCN. Optimization of 5-fluoro-2′-deoxyuridine (14) synthesis (pH 7.5, 10 mM phosphate buffer, nucleoside/nucleobase 3:1 molar ratio) and subsequent scale-up afforded the target compound in 73% (EcTP) or 76% (BsPyNP) conversion (about 9 g/L).