title: Interaction of myoglobin with oleic acid.
abstract: Previous studies have shown that palmitate (PA) can interact with myoglobin (Mb). The present study has investigated the interaction of the more soluble unsaturated fatty acid, oleic acid (OA). Indeed, (1)H NMR measurements of the Mb signal during OA titration also show signal changes consistent with specific and non-specific binding. At OA:Mb ratio<4:1, OA perturbs selectively the 8-heme methyl signal, consistent with a local and specific fatty acid-protein interaction. As OA:Mb ratio increases from 4:1 to 40:1, all hyperfine shifted MbCN signals decrease, consistent with a non-selective, global perturbation of the protein. The pH titration analysis indicates that the observed OA methylene signal in the presence of Mb reflects a non-specific interaction and does not originate from a shift in the lamella-micelle equilibrium. Given the OA interaction with Mb, a fatty acid flux model suggests that Mb can play a fatty acid transport role under certain physiological conditions.
authors.affiliation: Biochemistry and Molecular Medicine, University of California, Davis, Davis CA 95616-8635, United States.
authors.forename: Lifan
authors.initials: L
authors.lastname: Shih
authors.affiliation: Biochemistry and Molecular Medicine, University of California, Davis, Davis CA 95616-8635, United States.
authors.forename: Youngran
authors.initials: Y
authors.lastname: Chung
authors.affiliation: Biochemistry and Molecular Medicine, University of California, Davis, Davis CA 95616-8635, United States.
authors.forename: Renuka
authors.initials: R
authors.lastname: Sriram
authors.affiliation: Biochemistry and Molecular Medicine, University of California, Davis, Davis CA 95616-8635, United States. Electronic address: TJue@ucdavis.edu.
authors.forename: Thomas
authors.initials: T
authors.lastname: Jue
mesh_terms: D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D009211:Myoglobin / Q000737:chemistry* / Q000378:metabolism; D019301:Oleic Acid / Q000737:chemistry* / Q000378:metabolism; D012995:Solubility
chemical_list: D008823:Micelles; D009211:Myoglobin; D019301:Oleic Acid
keywords: Bioenergetics; Fatty acid; Lipid; Lipid–protein interaction; Metabolism; NMR