Publication Abstract from PubMed
The crystal structure of AzoR (azoreductase) has been determined in complex with FMN for two different crystal forms at 1.8 and 2.2 A resolution. AzoR is an oxidoreductase isolated from Escherichia coli as a protein responsible for the degradation of azo compounds. This enzyme is an FMN-dependent NADH-azoreductase and catalyzes the reductive cleavage of azo groups by a ping-pong mechanism. The structure suggests that AzoR acts in a homodimeric state forming the two identical catalytic sites to which both monomers contribute. The structure revealed that each monomer of AzoR has a flavodoxin-like structure, without the explicit overall amino acid sequence homology. Superposition of the structures from the two different crystal forms revealed the conformational change and suggested a mechanism for accommodating substrates of different size. Furthermore, comparison of the active site structure with that of NQO1 complexed with substrates provides clues to the possible substrate-binding mechanism of AzoR.
Three-dimensional structure of AzoR from Escherichia coli. An oxidereductase conserved in microorganisms.,Ito K, Nakanishi M, Lee WC, Sasaki H, Zenno S, Saigo K, Kitade Y, Tanokura M J Biol Chem. 2006 Jul 21;281(29):20567-76. Epub 2006 May 9. PMID:16684776[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.