1WLK

L122E mutant of FMN-binding protein from Desulfovibrio vulgaris (Miyazaki F)

Summary for 1WLK

• Entry DOI: 10.2210/pdb1wlk/pdb
• Related: 1FLM 1WLI 1WLL
• Descriptor: FMN-binding protein, FLAVIN MONONUCLEOTIDE (3 entities in total)
• Functional Keywords: electron transport, flavoprotein, fmn
• Biological source: Desulfovibrio vulgaris str. 'Miyazaki F'
• Cellular location: Cytoplasm: Q46604
• Total number of polymer chains: 4
• Total formula weight: 54501.46

Authors

Shibata, N.,Higuchi, Y. (deposition date: 2004-06-28, release date: 2005-07-19, Last modification date: 2024-05-29)

Primary citation

Kitamura, M.,Terakawa, K.,Inoue, H.,Hayashida, T.,Suto, K.,Morimoto, Y.,Yasuoka, N.,Shibata, N.,Higuchi, Y.
Determination of the role of the Carboxyl-terminal leucine-122 in FMN-binding protein by mutational and structural analysis.
J.Biochem., 141:459-468, 2007

PubMed Abstract: Mutants of flavin mononucleotide-binding protein (FMN-bp) were made by site-directed mutagenesis to investigate the role of carboxyl-terminal Leu122 of the pairing subunit in controlling redox potentials, binding the prosthetic group, and forming the tertiary and quaternary structure. We compared the oxidation-reduction potentials, FMN-binding properties, and higher structures of wild-type FMN-bp and four mutant proteins (L122Y, L122E, L122K and L122-deleted). We found that the redox potentials were affected by mutations. Also, the affinities of L122E, L122K and L122 deletion mutant apoproteins for FMN were lower than for the wild-type apoprotein, whereas the affinity of L122Y for FMN was increased. Analytical ultracentrifugation showed that the dissociation constants for dimerization of L122E and L122K were larger than for wild-type FMN-bp, whereas the dissociation constants for L122Y and the deletion mutant were lower than for the wild type. Finally, we determined the higher structures of L122Y, L122E and L122K mutants by X-ray crystallography. Our results show that the mutation of Leu122 in FMN-bp changes midpoint potentials, dissociation constants for FMN, and dimer formation, indicating that this residue is important in the pairing subunit.

PubMed: 17261542
DOI: 10.1093/jb/mvm051

Experimental method

X-RAY DIFFRACTION (1.9 Å)