Fig. 2.

Activity of recombinant G. lamblia nitroreductases GlNR1 (NR1) and GlNR2 (NR2) with menadione (Men) or dinitrotoluene (DNT) as substrates (0.1 mM). DMSO was included as a solvent control, thus as a substrate blank. Functional assays were performed with NADH as an electron donor and MTT as chromogenic electron acceptor. The reaction was performed at 37 °C under normal atmosphere (aerobic) or in an anaerobic chamber (100% N₂; anaerobic) and stopped after 2 h addition of one volume pure ethanol. Mean values (±SE) are given for three replicates.