One-Pot Multi-Enzymatic Production of Purine Derivatives with Application in Pharmaceutical and Food Industry

Javier Acosta, Jon del Arco, Sara Martinez-Pascual, Vicente Clemente-Suárez, Jesús Fernández-Lucas
2018 Catalysts  
Biocatalysis reproduce nature's synthetic strategies in order to synthesize different organic compounds. Natural metabolic pathways usually involve complex networks to support cellular growth and survival. In this regard, multi-enzymatic systems are valuable tools for the production of a wide variety of organic compounds. Methods: The production of different purine nucleosides and nucleoside-5 -monophosphates has been performed for first time, catalyzed by the sequential action of 2
more » ... ltransferase from Lactobacillus delbrueckii (LdNDT) and hypoxanthine-guanine-xanthine phosphoribosyltransferase from Thermus themophilus HB8 (TtHGXPRT). Results: The biochemical characterization of LdNDT reveals that the enzyme is active and stable in a broad range of pH, temperature, and ionic strength. Substrate specificity studies showed a high promiscuity in the recognition of purine analogues. Finally, the enzymatic production of different purine derivatives was performed to evaluate the efficiency of multi-enzymatic system LdNDT/TtHGXPRT. Conclusions: The production of different therapeutic purine nucleosides was efficiently catalyzed by LdNDT/TtHGXPRT. In addition, the resulting by-products were converted to IMP and GMP. Taking all of these features, this bioprocess entails an efficient, sustainable, and economical alternative to chemical synthetic methods. Catalysts 2018, 8, 9 2 of 12 sensation [3] . As a result, current demand for nucleotides in the food additives market is increasing, and the production of nucleotides has been widely studied. NAs and NMPs have been traditionally synthesized by chemical methods through multistep processes requiring protection and de-protection steps for the labile groups, and isolation in almost every step due to the poor regio-or stereoselectivity of the reactions [4] [5] [6] [7] [8] . These drawbacks lead to a high price of these valuable compounds, limiting their application. Nowadays, the application of bioprocesses that are catalyzed by whole cells or enzymes in industry is gaining ground against traditional chemical synthetic processes. In this context, the enzymatic synthesis of NAs and NMPs shows many advantages, such as one-pot reactions under mild conditions, high stereo-, and regioselectivity, and an environmentally friendly technology [4] [5] [6] [7] [8] [9] [10] [11] . Purine metabolism is a metabolic route of vital importance in all the living organisms, since purines are essential for the synthesis of nucleic acids (DNA and RNA), proteins, and other metabolites. In the de novo pathway cells use simple precursors like glycine, glutamine, or aspartate for the synthesis of the different purine nucleotides. On the contrary, the salvage pathway is composed by a group of reutilization routes by which the cell can satisfy its purine requirements from endogenous and/or exogenous sources of preformed purines. In this regard, numerous enzymes from purine salvage pathway have become valuable catalysts for mono or multi-enzymatic synthesis of nucleosides and nucleotides, such as nucleoside kinases (NKs) [12] [13] [14] [15] , phosphoribosyltransferases [7, [9] [10] [11] , nucleoside phosphorylases [4, 8, 16, 17] , 2 -deoxyribosyltransferases [5, [18] [19] [20] , among others. The use of multi-enzymatic systems in organic synthesis offers several advantages, such as the realization of more complex synthetic schemes, the ability to make reversible processes irreversible, to shift the equilibrium reaction in desired way, and the partial or total elimination of product inhibition problems or the prevention of the shortage of substrates by dilution or degradation in the bulk media [13] . In this regard, the aim of this work is the development of a novel multi-enzymatic system for the industrial production of different NAs and NMPs with application in pharmaceutical and food industry. To achieve this objective, an in vitro multienzymatic system composed by 2 -deoxyribosyltransferase from Lactobacillus delbrueckii (LdNDT) and the hypoxanthine-guanine-xanthine phosphoribosyltransferase from Thermus themophilus HB8 (TtHGXPRT), is developed. As shown in Figure 1 , the sequential action of LdNDT and hypoxanthine-guanine-xanthine TtHGXPRT can efficiently catalyze the synthesis of NAs and NMPs in two steps.
doi:10.3390/catal8010009 fatcat:z6wy54sy65f2bacmpf3nz427ly