The Nitrate reductase enzyme complex allows bacteria to use nitrate as an electron acceptor during anaerobic growth. The enzyme complex consists of a tetramer that has an alpha, beta and 2 gamma subunits. The alpha and beta subunits have catalytic activity and the gamma subunits attach the enzyme to the membrane and is a b-type cytochrome that receives electrons from the quinone pool and transfers them to the beta subunit. This model is specific for the alpha subunit for nitrate reductase I (narG) and nitrate reductase II (narZ) for gram positive and gram negative bacteria.A few thermophiles and archaea also match the model The seed members used to make the model include Nitrate reductases from Pseudomonas fluorescens (GP:11344601), E.coli (SP:P09152) and B.subtilis (SP:P42175). All seed members are experimentally characterized. Some unpublished nitrate reductases, that are shorter sequences, and probably fragments fall in between the noise and trusted cutoffs. Pfam models pfam00384 (Molybdopterin oxidoreductase) and pfam01568(Molydopterin dinucleotide binding domain) will also match the nitrate reductase, alpha subunit. [Energy metabolism, Anaerobic]
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