Nitrosomonas europaea is a chemolithoautotrophic bacterium that oxidizes ammonia (NH₃) to obtain energy for growth on carbon dioxide (CO₂) and can also produce nitrous oxide (N₂O), a greenhouse gas. We interrogated the growth, physiological, and transcriptome responses of N. europaea to conditions of replete (>5.2 mM) and limited inorganic carbon...