1F5V

STRUCTURE AND SITE-DIRECTED MUTAGENESIS OF A FLAVOPROTEIN FROM ESCHERICHIA COLI THAT REDUCES NITROCOMPOUNDS. ALTERATION OF PYRIDINE NUCLEOTIDE BINDING BY A SINGLE AMINO ACID SUBSTITUTION

Summary for 1F5V

• Entry DOI: 10.2210/pdb1f5v/pdb
• Descriptor: OXYGEN-INSENSITIVE NADPH NITROREDUCTASE, FLAVIN MONONUCLEOTIDE (3 entities in total)
• Functional Keywords: nitroreductase, flavoprotein, escherichia coli, oxidoreduction, nitrocompound, oxidoreductase
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 54578.02

Authors

Kobori, T.,Sasaki, H.,Lee, W.C.,Zenno, S.,Saigo, K.,Murphy, M.E.P.,Tanokura, M. (deposition date: 2000-06-17, release date: 2001-02-14, Last modification date: 2024-02-07)

Primary citation

Kobori, T.,Sasaki, H.,Lee, W.C.,Zenno, S.,Saigo, K.,Murphy, M.E.,Tanokura, M.
Structure and site-directed mutagenesis of a flavoprotein from Escherichia coli that reduces nitrocompounds: alteration of pyridine nucleotide binding by a single amino acid substitution.
J.Biol.Chem., 276:2816-2823, 2001

PubMed Abstract: The crystal structure of a major oxygen-insensitive nitroreductase (NfsA) from Escherichia coli has been solved by the molecular replacement method at 1.7-A resolution. This enzyme is a homodimeric flavoprotein with one FMN cofactor per monomer and catalyzes reduction of nitrocompounds using NADPH. The structure exhibits an alpha + beta-fold, and is comprised of a central domain and an excursion domain. The overall structure of NfsA is similar to the NADPH-dependent flavin reductase of Vibrio harveyi, despite definite difference in the spatial arrangement of residues around the putative substrate-binding site. On the basis of the crystal structure of NfsA and its alignment with the V. harveyi flavin reductase and the NADPH-dependent nitro/flavin reductase of Bacillus subtilis, residues Arg(203) and Arg(208) of the loop region between helices I and J in the vicinity of the catalytic center FMN is predicted as a determinant for NADPH binding. The R203A mutant results in a 33-fold increase in the K(m) value for NADPH indicating that the side chain of Arg(203) plays a key role in binding NADPH possibly to interact with the 2'-phosphate group.

PubMed: 11034992
DOI: 10.1074/jbc.M002617200

Experimental method

X-RAY DIFFRACTION (1.7 Å)