1V4B

The crystal structure of AzoR (Azo Reductase) from Escherichia coli: Oxidized form

Summary for 1V4B

• Entry DOI: 10.2210/pdb1v4b/pdb
• Related: 1V4C
• Descriptor: NADH-azoreductase, FMN-dependent, FLAVIN MONONUCLEOTIDE, 1,2-ETHANEDIOL, ... (5 entities in total)
• Functional Keywords: azo reductase, oxidoreductase
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 22125.95

Authors

Ito, K.,Tanokura, M. (deposition date: 2003-11-12, release date: 2005-01-18, Last modification date: 2023-12-27)

Primary citation

Ito, K.,Nakanishi, M.,Lee, W.C.,Sasaki, H.,Zenno, S.,Saigo, K.,Kitade, Y.,Tanokura, M.
Three-dimensional structure of AzoR from Escherichia coli. An oxidereductase conserved in microorganisms
J.Biol.Chem., 281:20567-20576, 2006

PubMed Abstract: 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.

PubMed: 16684776
DOI: 10.1074/jbc.M513345200

Experimental method

X-RAY DIFFRACTION (1.8 Å)