title: Structural basis for the mutation-induced dysfunction of human CYP2J2: a computational study.
abstract: Arachidonic acid is an essential fatty acid in cells, acting as a key inflammatory intermediate in inflammatory reactions. In cardiac tissues, CYP2J2 can adopt arachidonic acid as a major substrate to produce epoxyeicosatrienoic acids (EETs), which can protect endothelial cells from ischemic or hypoxic injuries and have been implicated in the pathogenesis of coronary artery disease and hypertension. However, some CYP2J2 polymorphisms, i.e., T143A and N404Y, significantly reduce the metabolism of arachidonic acid. Lacking experimental structural data for CYP2J2, the detailed mechanism for the mutation-induced dysfunction in the metabolism of arachidonic acid is still unknown. In the current study, three-dimensional structural models of the wild-type CYP2J2 and two mutants (T143A and N404Y) were constructed by a coordinate reconstruction approach and ab initio modeling using CYP2R1 as a template. The structural analysis of the computational models showed that the wild-type CYP2J2 exhibited a typical CYP fold with 12 alpha-helices and three beta-sheets on one side and with the heme group buried deeply inside the core. Due to the small and hydrophobic side-chain, T143A mutation could destabilize the C helix, further placing the water access channel in a closed state to prevent the escape of the produced water molecules during the catalytic processes. N404Y mutation could reposition the side-chain of Leu(378), making it no longer form a hydrogen bond with the carboxyl group of arachidonic acid. However, this hydrogen bond was essential for substrate recognition and positioning in a correct orientation.
authors: Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, China.
authors: Shan
authors: S
authors: Cong
authors: Xiao-Tu
authors: XT
authors: Ma
authors: Yi-Xue
authors: YX
authors: Li
authors: Jing-Fang
authors: JF
authors: Wang
mesh_terms: D016718:Arachidonic Acid / Q000378:metabolism; D000090762:Cytochrome P-450 CYP2J2; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D056004:Molecular Dynamics Simulation; D017354:Point Mutation; D017433:Protein Structure, Secondary; D013816:Thermodynamics
chemical_list: C000717350:CYP2J2 protein, human; D016718:Arachidonic Acid; D003577:Cytochrome P-450 Enzyme System; D000090762:Cytochrome P-450 CYP2J2