title: Phylogenomics of Mycobacterium Nitrate Reductase Operon.
abstract: NarGHJI operon encodes a nitrate reductase that can reduce nitrate to nitrite. This process enhances bacterial survival by nitrate respiration under anaerobic conditions. NarGHJI operon exists in many bacteria, especially saprophytic bacteria living in soil which play a key role in the nitrogen cycle. Most actinomycetes, including Mycobacterium tuberculosis, possess NarGHJI operons. M. tuberculosis is a facultative intracellular pathogen that expands in macrophages and has the ability to persist in a non-replicative form in granuloma lifelong. Nitrogen and nitrogen compounds play crucial roles in the struggle between M. tuberculosis and host. M. tuberculosis can use nitrate as a final electron acceptor under anaerobic conditions to enhance its survival. In this article, we reviewed the mechanisms regulating nitrate reductase expression and affecting its activity. Potential genes involved in regulating the nitrate reductase expression in M. tuberculosis were identified. The conserved NarG might be an alternative mycobacterium taxonomic marker.
authors.affiliation: Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, 1 Rd Tiansheng, Beibei, Chongqing, 400715, People's Republic of China.
authors.forename: Qinqin
authors.initials: Q
authors.lastname: Huang
authors.forename: Abualgasim Elgaili
authors.initials: AE
authors.lastname: Abdalla
authors.forename: Jianping
authors.initials: J
authors.lastname: Xie
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D009169:Mycobacterium tuberculosis / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D050901:Nitrate Reductase / Q000235:genetics*; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D009876:Operon; D010802:Phylogeny
chemical_list: D009566:Nitrates; D009573:Nitrites; D050901:Nitrate Reductase