J. Biochem, 1992, Vol. 112, No. 6 804-810
© 1992 Japanese Biochemical Society
research-article |
The Binding of Adenine Nucleotides to Apo-Electron-Transferring Flavoprotein1
Deparpment of Physiology, Kumamoto University School of Medicine Honjo, Kumamoto, Kumamoto 860
Apoprotein of electron-transferring flavoprotein (ETF) reacts with FAD as follows: A*
A, A+FAD
holoETF. Two different forms of apoETF (A* and A) convert into each other and only one of them, A, can associate with FAD [Sato, K. et al. (1991) J. Biochem. 109, 734740]. In the present study, the reactions between apoETF and ATP, ADP, AMP, riboflavin, or FMN were investigated. It was revealed that all three adenine nucleotides bind with apoETF with the same kinetic reaction scheme as FAD, and compete with FAD. These results suggest that the nucleotides bind to A with the same location as the ADP part of FAD in holoETF and that the ADP-binding site of apoETF is generated upon conversion from A* to A. Neither riboflavin nor FMN bound to apoETF regardless of the presence or absence of the nucleotides, indicating that the ADP part of the FAD molecule is essential to the incorporation of the isoalloxazine ring into ETF. The binding rate constant of FAD to A was 1/20 of that of ADP while the dissociation rate constant was 1/1,000. This indicates that the riboflavin part of FAD inhibits the binding of FAD by steric hindrance, while after the binding, it stabilizes the complex.
1This Btudy was supported in part by a Grant-in- Aid for Scientific Resaerch from the Ministry of Education, Science and Culture of Japan.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
T. Saijo and K. Tanaka Isoalloxazine Ring of FAD Is Required for the Formation of the Core in the Hsp60-assisted Folding of Medium Chain Acyl-CoA Dehydrogenase Subunit into the Assembly Competent Conformation in Mitochondria J. Biol. Chem., January 27, 1995; 270(4): 1899 - 1907. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. W. Fraaije, R. H. H. van den Heuvel, W. J. H. van Berkel, and A. Mattevi Structural Analysis of Flavinylation in Vanillyl-Alcohol Oxidase J. Biol. Chem., December 1, 2000; 275(49): 38654 - 38658. [Abstract] [Full Text] [PDF] |
||||
