An unusually cold active nitroreductase for prodrug activations

作者：Celik Ayhan^*; Yetis Gulden

来源：Bioorganic & Medicinal Chemistry, 2012, 20(11): 3540-3550.

DOI：10.1016/j.bmc.2012.04.004

• Nitroreductase
• Cold active enzyme
• Prodrug activation
• CB1954
• Staphylococcus saprophyticus
• Nitrofurazone

A set of PCR primers based on the genome sequence were used to clone a gene encoding a hypothetical nitroreductases (named as Ssap-NtrB) from uropathogenic staphylococcus, Staphylococcus saprophyticus strain ATCC 15305, an oxygen insensitive flavoenzyme. Activity studies of the translation product revealed that the nitroreductase catalyses two electron reduction of a nitroaromatic drug of nitrofurazone (NFZ), cancer prodrugs of CB1954 and SN23862 at optimum temperature of 20 degrees C together with retaining its maximum activity considerably at 3 degrees C. The required electrons for such reduction could be supplied by either NADH or NADPH with a small preference for the latter. The gene was engineered for heterologous expression in Escherichia coli, and conditions were found in which the enzyme was produced in a mostly soluble form. The recombinant enzyme was purified to homogeneity and physical, spectral and catalytical properties were determined. The findings lead us to propose that Ssap-NtrB represents a novel nitro reductase with an unusual cold active property, which has not been described previously for prodrug activating enzymes of nitroreductases.

• 出版日期2012-6-1