Factors Affecting Nitroreductase Activity in the Biological Reduction of Nitro Compounds

Nitro compounds are used in various industries, including the pharmaceutical industry. These compounds have considerable importance for human health for two distinctly different reasons. Some nitro compounds are toxic environmental contaminants and pose a serious threat to human health; others are used as therapeutic agents. Nitro compounds are used as agents for the treatment of infectious diseases caused by Grampositive and Gram-negative bacteria, as antifungal and antiparasitic drugs, and as chemotherapeutic agents. To exert either beneficial or adverse biological effects, nitro compounds require enzymatic activation, either by nitroreduction alone or by ring oxidation followed by nitroreduction. The mechanism of drug action relies on the toxicity of the products generated by nitroreductases. Nitroreductases differ in the range of specificity and levels of activity with various nitro prodrugs. In this review, factors affecting nitroreductase activity, especially compounds that inhibit reduction, will be discussed.