FIGURE 3.

Formation of red myoglobin derivatives. S. xylosus C2apRB473, ΔnospRB473 and ΔnospRBnos were incubated in TSB supplemented with metmyoglobin (2 mg/mL) under (A) limited oxygenation (no stirring and reaction mixture covered with mineral oil) and (B) aerobic conditions (150 rpm). Formation of red pigment was evaluated by measuring absorbance. Data represent means ± SD from n = 3 independent biological replicates. **p < 0.01; ***p < 0.001 at λ_{548 nm} and λ_{581 nm.}