Fig. 5

Engineering strategy for thymidine production. The gene tdk was deleted, and the gene prs was overexpressed by integrating a strong promoter via single crossover recombination; The genes ushA, thyA, dut, and ndk from E. coli were overexpressed from a plasmid under the control of the strong P43 promoter. The gene abbreviations are as follows: tdk encodes thymidine kinase; ushA encodes 5′-nucleotidase/UDP-sugar diphosphatase; thyA encodes thymidylate synthase; dut encodes dUTP pyrophosphatase; ndk encodes nucleoside-diphosphate kinase