title: Mammalian electron transferring flavoprotein.flavoprotein dehydrogenase complexes observed by microelectrospray ionization-mass spectrometry and surface plasmon resonance.
abstract: Microelectrospray ionization-mass spectrometry was used to directly observe electron transferring flavoprotein.flavoprotein dehydrogenase interactions. When electron transferring flavoprotein and porcine dimethylglycine dehydrogenase or sarcosine dehydrogenase were incubated together in the absence of substrate, a relative molecular mass corresponding to the flavoprotein.electron transferring flavoprotein complex was observed, providing the first direct observation of these mammalian complexes. When an acyl-CoA dehydrogenase family member, human short chain acyl-CoA dehydrogenase, was incubated with dimethylglycine dehydrogenase and electron transferring flavoprotein, the microelectrospray ionization-mass spectrometry signal for the dimethylglycine dehydrogenase.electron transferring flavoprotein complex decreased, indicating that the acyl-CoA dehydrogenases have the ability to compete with the dimethylglycine dehydrogenase/sarcosine dehydrogenase family for access to electron transferring flavoprotein. Surface plasmon resonance solution competition experiments revealed affinity constants of 2.0 and 5.0 microm for the dimethylglycine dehydrogenase-electron transferring flavoprotein and short chain acyl-CoA dehydrogenase-electron transferring flavoprotein interactions, respectively, suggesting the same or closely overlapping binding motif(s) on electron transferring flavoprotein for dehydrogenase interaction.
authors.affiliation: Departments of Biochemistry and Molecular Biology and Medical Genetics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
authors.forename: Heidi M
authors.initials: HM
authors.lastname: Hoard-Fruchey
authors.forename: Eric
authors.initials: E
authors.lastname: Goetzman
authors.forename: Linda
authors.initials: L
authors.lastname: Benson
authors.forename: Stephen
authors.initials: S
authors.lastname: Naylor
authors.forename: Jerry
authors.initials: J
authors.lastname: Vockley
mesh_terms: D042964:Acyl-CoA Dehydrogenase / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D044927:Electron-Transferring Flavoproteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000201:enzymology; D008322:Mammals; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D020349:Surface Plasmon Resonance / Q000379:methods*; D013552:Swine
chemical_list: D044927:Electron-Transferring Flavoproteins; D042964:Acyl-CoA Dehydrogenase