Transcriptome profile of the Hydrogenobacter thermophilus TK-6 cells aerobically or anaerobically grown on ammonium, nitrate, or mix of ammonium and nitrate was determined by NimbleGen Eukaryotic Expression array (4x72K). Overall design: Hydrogenobacter thermophilus TK-6 was aerobically or anaerobically grown on ammonium or nitrate as nitrogen sources in sealed vials with shaking. Total RNA was extracted when optical density at 600 nm was 0.4-0.5. The experiment was performed in duplicate independent cultures.