Function
Nitrate reductase plays a strong role in the nitrogen cycle. It fixes nitrate to nitrite so it can be more easily converted to nitrogen gas for the atmosphere. Nitrate reduction can also cause increases in the levels of phosphate in groundwater. [1] narG consists of 3 sub-units; G, H, and I. The G sub-unit contains the active site of narG while the other sub-units are involved in electron transport.
Relevance
Nitrates from agricultural runoff can pollute bodies of water and damage the ecosystem. When nitrate concentration increases in water sources, it leads to algal blooms and eutrophication which can drastically reduce the species diversity of the water source. [2] Mutations of narG can result in a reduced efficiency to fix nitrates to nitrogen. This could be a potential bioremediation pathway to study.
Structural highlights
where nitrate is fixed to nitrite. The molybdenum molecule is responsible for nitrate reduction. The FS0 cluster is a potential electron transfer route for the molybdenum core. [3]
where mutations can occur that prevent the FS0 cluster from binding, specifically a mutation to .
has been mutated to a Serine. This can reduce enzyme efficiency by removal of the positive charge of Arginine.
