eight-bladed beta-propeller heme-binding domain in cytochrome cd1 and similar proteins
Members here contain an 8-bladed beta-propeller heme-binding domain in cytochrome cd1 (nitrite reductase) and similar proteins including NirN and NirF. During denitrification, nitrate (Nar), nitrite (Nir), nitric oxide (Nor), and nitrous oxide (Nos) reductases catalyze the reaction cascade of NO(3-)-> NO(2-)-> NO -> N2O -> N2. The integral membrane proteins NorC, NorB, and NosR form the core assembly platform that binds the nitrate reductase NarGHI and the periplasmic nitrite reductase NirS via its maturation factor NirF. NirN and NirF form a stable complex with the nitrite reductase NirS during enzyme maturation. NirF is involved in heme d1 insertion.
Jiyao W et al.(2023). "The conserved domain database in 2023.",