Crystal structure of chorismate synthase: a novel FMN-binding protein fold and functional insights.
Article Details
- CitationCopy to clipboard
Ahn HJ, Yoon HJ, Lee B 2nd, Suh SW
Crystal structure of chorismate synthase: a novel FMN-binding protein fold and functional insights.
J Mol Biol. 2004 Feb 27;336(4):903-15.
- PubMed ID
- 15095868 [ View in PubMed]
- Abstract
Chorismate synthase catalyzes the conversion of 5-enolpyruvylshikimate 3-phosphate to chorismate in the shikimate pathway, which represents an attractive target for discovering antimicrobial agents and herbicides. Chorismate serves as a common precursor for the synthesis of aromatic amino acids and many aromatic compounds in microorganisms and plants. Chorismate synthase requires reduced FMN as a cofactor but the catalyzed reaction involves no net redox change. Here, we have determined the crystal structure of chorismate synthase from Helicobacter pylori in both FMN-bound and FMN-free forms. It is a tetrameric enzyme, with each monomer possessing a novel "beta-alpha-beta sandwich fold". Highly conserved regions, including several flexible loops, cluster together around the bound FMN to form the active site. The unique FMN-binding site is formed largely by a single subunit, with a small contribution from a neighboring subunit. The isoalloxazine ring of the bound FMN is significantly non-planar. Our structure illuminates the essential functional roles played by the cofactor.