title: Crystal Structure and Atomic Level Analysis of Plasma PAF-AH.
abstract: The structure of plasma PAF-AH was solved to a resolution of 1.5Å using X-ray crystallography. The enzyme has a classic α/β serine hydrolase fold containing a catalytic triad of Ser273, Asp296, and His351. A hydrophobic patch of the enzyme involving two α-helices (114-126 and 362-369) and neighboring residues have been shown to be essential for lipoprotein particle binding by mutagenesis and mass spectrometry hydrogen/deuterium exchange experiments. An interface-bound model of the enzyme positions the active site above the hydrophobic-hydrophilic interface and is consistent with the known substrate specificity of the enzyme. Several ligand-bound structures of plasma PAF-AH have been solved with organophosphorus compounds and modeled with competitive inhibitors of high affinity and selectivity. This chapter presents an overview of the structure of plasma PAF-AH, molecular details of its functional role, and the interaction of the enzyme with lipoprotein particles.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA.
authors.forename: Tara D
authors.initials: TD
authors.lastname: Gonzalez
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA. Electronic address: bahnson@udel.edu.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Bahnson
keywords: Crystal structure; Group-VIIa PLA(2); HDL; LDL; Lipoprotein particles; Lp-PLA(2); Membrane associated