Fig. 5

Instantaneous O₂ consumption and N₂O production during NH₃ oxidation by N. inopinata. The data shown here is a single representative of three biological replicates (n = 3). Two additional biological replicates are shown in Supplementary Fig. 9. Dissolved O₂ is shown in open circles, dissolved N₂O in filled gray triangles, NO₂⁻ in open diamonds, and NH₄⁺ in filled squares. The NH₄⁺ concentration immediately after injection (~23 min) was inferred from the injected volume of a stock NH₄Cl solution, otherwise NO₂⁻ and NH₄⁺ concentrations were determined in three technical replicates (n = 3). Experiments were performed in a 10-mL microrespiration (MR) chamber fitted with O₂ and N₂O microsensors. The arrow marks the addition of 250 µM NH₄Cl into the MR chamber. About 110 µM residual NO₂⁻ was present in the chamber once O₂ reached below the detectable level at ~45 min. Source data are provided as a Source Data file