Enhanced production of cytidine 5′-monophosphate using biocatalysis of di-enzymes immobilized on amino-functionalized sepharose

Cytidine 5′-monophosphate (5′-CMP) is an essential nucleotide for additives. In this study, enhanced production of 5′-CMP was realized by the transformation of cytidine using co-immobilized di-enzymes, uridine-cytidine kinase (UCK) and acetate kinase (AcK). The immobilization yield of the enzyme had a clear correlation with the surface charges as zeta potential (ξ). Among them, ε-polylysine-functionalized sepharose (SA-EPL, ξ = 9.31 mV) showed high immobilization yield (78.8%), which was 4.9-fold than that of nitrilotriacetic acid functionalized sepharose (SA-NTA, ξ = −12.6 mV). The residual activity of affinity co-immobilized enzyme (EPL-Ni/EPL@AcK-UCK) was higher than 70.6% after recycled 10 times. Thus, this study provides an effective approach for the production of 5′-CMP with the advantages of low adenosine 5′-triphosphate (ATP) consumption, reduced side reactions, and improved reusability by co-immobilized UCK and AcK on the functionalized Sepharose.