Sequence similarities of nitroreductases. The amino acid sequence encoding various nitroreductases were aligned. Identical residues are highlighted in black, and conserved substitutions are highlighted in grey. The sequences represent (Bacterium, Genebank identification number): Escherichia coli NP_415110.1, N. gonorrhoeae FA1090, NC002946; Haemophilus influenzae, Q57431; Bacillus subtilis; O34475; Helicobacter pylori, NP459570; and Agrobacterium tumefaciens str. C58, NP534964.