An ultracentrifugal approach to quantitative characterization of the molecular assembly of a physiological electron-transfer complex: the interaction of electron-transferring flavoprotein with trimethylamine dehydrogenase.
نویسندگان
چکیده
The interaction between two physiological redox partners, trimethylamine dehydrogenase and electron-transferring flavoprotein, has been characterized quantitatively by analytical ultracentrifugation at 4 degrees C. Analysis of sedimentation-equilibrium distributions obtained at 15 000 rpm for mixtures in 10 mM potassium phosphate, pH 7.5, by means of the psi function [Wills, P. R., Jacobsen, M. P. & Winzor, D. J. (1996) Biopolymers 38, 119-130] has yielded an intrinsic dissociation constant of 3-7 microM for the interaction of electron-transferring flavoprotein with two equivalent and independent sites on the homodimeric enzyme. This investigation indicates the potential of sedimentation equilibrium for the quantitative characterization of interactions between dissimilar macromolecules.
منابع مشابه
X-ray scattering studies of Methylophilus methylotrophus (sp. W3A1) electron-transferring flavoprotein. Evidence for multiple conformational states and an induced fit mechanism for assembly with trimethylamine dehydrogenase.
Small angle x-ray solution scattering has been used to generate a low resolution, model-independent molecular envelope structure for electron-transferring flavoprotein (ETF) from Methylophilus methylotrophus (sp. W(3)A(1)). Analysis of both the oxidized and 1-electron-reduced (anionic flavin semiquinone) forms of the protein revealed that the solution structures of the protein are similar in bo...
متن کاملFlavin radicals, conformational sampling and robust design principles in interprotein electron transfer: the trimethylamine dehydrogenase-electron-transferring flavoprotein complex.
TMADH (trimethylamine dehydrogenase) is a complex iron-sulphur flavoprotein that forms a soluble electron-transfer complex with ETF (electron-transferring flavoprotein). The mechanism of electron transfer between TMADH and ETF has been studied using stopped-flow kinetic and mutagenesis methods, and more recently by X-ray crystallography. Potentiometric methods have also been used to identify ke...
متن کاملThe Natural Flavoprotein Electron Acceptor of Trimeihylamine Dehydrogenase*
The isolation and partial characterization of a flavoprotein which functions as the electron acceptor of trimethylamine dehydrogenase (EC 1.5.99.7) from a methylotrophic bacterium is described. It has a molecular weight of 77,000 and is composed of two dissimilar subunits. All preparations examined contained only 1 mol of FAD/m01 of the flavoprotein. Trimethylamine dehydrogenase, in the presenc...
متن کاملMammalian electron transferring flavoprotein.flavoprotein dehydrogenase complexes observed by microelectrospray ionization-mass spectrometry and surface plasmon resonance.
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 f...
متن کاملFrataxin interacts functionally with mitochondrial electron transport chain proteins.
Frataxin deficiency is the main cause of Friedreich ataxia, an autosomal recessive neurodegenerative disorder. Frataxin function in mitochondria has not been fully explained yet. In this work, we show that Saccharomyces cerevisiae frataxin orthologue Yfh1p interacts physically with succinate dehydrogenase complex subunits Sdh1p and Sdh2p of the yeast mitochondrial electron transport chain and a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- European journal of biochemistry
دوره 243 1-2 شماره
صفحات -
تاریخ انتشار 1997