COMPARATIVE OPTICALLY DETECTED MAGNETIC-RESONANCE STUDIES OF MAMMALIAN PHOSPHOLIPASE-A2-LIPID INTERACTIONS

作     者：MAO, SY MAKI, AH DEHAAS, GH 

作者机构：UNIV CALIF DAVISDEPT CHEMDAVISCA 95616 RIJKSUNIV UTRECHTBIOCHEM LAB3508 TB UTRECHTNETHERLANDS 

出 版 物：《FEBS LETTERS》 (欧洲生化学会联合会快报)

年 卷 期：1987年第211卷第1期

页      面：83-88页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 07[理学] 

基　　金：National ScienceF oun-dation 

主　　题：ODMR Phospholipase A 2 Protein-lipid interaction Tryptophan C 16 -PC, n -hexadecylphosphocholine CMC, critical micellar concentration ODMR, optically detected magnetic resonance PA 2 , pancreatic phospholipase A 2 ZFS, zero field splittings 

摘      要：A major difference between porcine and bovine pancreatic phospholipase A2 (PA2) is the relatively low affinity of the bovine enzyme for lipid-water interfaces. We have investigated the binding of porcine, bovine, and equine PA2 to n-hexadecylphosphocholine (C16-PC) micelles using optically detected magnetic resonance (ODMR) spectroscopy. The zero field splittings (ZFS) of the single Trp-3 residue undergo significant changes upon binding of PA2 to C16-PC micelles. ZFS titrations of PA2 vs C16-PC indicate that porcine and equine enzymes have similar binding affinity and stoichiometry, while bovine PA2 binds much more weakly to the lipid-water interfaces. This may be attributed to the differences in the amino acid composition and the conformation of the binding sites for lipid-water interfaces of these enzymes.