FIG. 3.

Effects of different WO₄²⁻ concentrations on NO₂⁻ accumulation in the medium. P. aerophilum was grown anaerobically with 0.05% peptone, 0.05% yeast extract, 10 mM NO₃⁻, and the different WO₄²⁻ concentrations indicated. The concentration of NO₂⁻ was determined when the cultures reached stationary phase. The results represent the means of more than eight independent growth experiments with cells that had been previously adapted to the various tungstate concentrations.