BIOMAT Database Logo BIOMAT Database Logo

Probable reaction mechanisms of flavokinase and FAD synthetase from rat liver. 1990

Y Yamada, and A H Merrill, and D B McCormick
Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322.

A steady-state kinetic analysis with evaluation of product inhibition was accomplished with purified rat liver flavokinase and FAD synthetase. For flavokinase, Km values were calculated as approximately 11 microM for riboflavin and 3.7 microM for ATP. Ki values were calculated for FMN as 6 microM against riboflavin and for ZnADP as 120 microM against riboflavin and 23 microM against ZnATP. From the inhibition pattern, the flavokinase reaction followed an ordered bi bi mechanism in which riboflavin binds first followed by ATP; ADP is released first followed by FMN. For FAD synthetase, Km values were calculated as 9.1 microM for FMN and 71 microM for MgATP. Ki values were calculated for FAD as 0.75 microM against FMN and 1.3 microM against MgATP and for pyrophosphate as 66 microM against FMN. The product inhibition pattern suggests the FAD synthetase reaction also followed an ordered bi bi mechanism in which ATP binds to enzyme prior to FMN, and pyrophosphate is released from enzyme before FAD. Comparison of Ki values with physiological concentrations of FMN and FAD suggests that the biosynthesis of FAD is most likely regulated by this coenzyme as product at the stage of the FAD synthetase reaction.

UI MeSH Term Description Entries
D007700 Kinetics The rate dynamics in chemical or physical systems.
D008099 Liver A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances. Livers
D008433 Mathematics The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed) Mathematic
D008962 Models, Theoretical Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment. Experimental Model,Experimental Models,Mathematical Model,Model, Experimental,Models (Theoretical),Models, Experimental,Models, Theoretic,Theoretical Study,Mathematical Models,Model (Theoretical),Model, Mathematical,Model, Theoretical,Models, Mathematical,Studies, Theoretical,Study, Theoretical,Theoretical Model,Theoretical Models,Theoretical Studies
D009713 Nucleotidyltransferases A class of enzymes that transfers nucleotidyl residues. EC 2.7.7. Nucleotidyltransferase
D010770 Phosphotransferases A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7. Kinases,Phosphotransferase,Phosphotransferases, ATP,Transphosphorylase,Transphosphorylases,Kinase,ATP Phosphotransferases
D011485 Protein Binding The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments. Plasma Protein Binding Capacity,Binding, Protein
D005486 Flavin Mononucleotide A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues. FMN,Flavin Mononucleotide Disodium Salt,Flavin Mononucleotide Monosodium Salt,Flavin Mononucleotide Monosodium Salt, Dihydrate,Flavin Mononucleotide Sodium Salt,Riboflavin 5'-Monophosphate,Riboflavin 5'-Phosphate,Riboflavin Mononucleotide,Sodium Riboflavin Phosphate,5'-Monophosphate, Riboflavin,5'-Phosphate, Riboflavin,Mononucleotide, Flavin,Mononucleotide, Riboflavin,Phosphate, Sodium Riboflavin,Riboflavin 5' Monophosphate,Riboflavin 5' Phosphate,Riboflavin Phosphate, Sodium
D000255 Adenosine Triphosphate An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter. ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia

Related Publications

Y Yamada, and A H Merrill, and D B McCormick
Flavokinase and FAD synthetase from Bacillus subtilis specific for reduced flavins.
October 1979, The Journal of biological chemistry,
Y Yamada, and A H Merrill, and D B McCormick
Purification and general characterization of FAD synthetase from rat liver.
February 1983, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.),
Y Yamada, and A H Merrill, and D B McCormick
Complete purification and general characterization of FAD synthetase from rat liver.
May 1987, The Journal of biological chemistry,
Y Yamada, and A H Merrill, and D B McCormick
Purification and properties of FAD synthetase from liver.
January 1997, Methods in enzymology,
Y Yamada, and A H Merrill, and D B McCormick
Mammalian flavokinase and FAD synthetase: functions of divalent metal ions and arginyl residues in the anionic substrate sites.
January 1992, Journal of nutritional science and vitaminology,
Y Yamada, and A H Merrill, and D B McCormick
The antibiotics roseoflavin and 8-demethyl-8-amino-riboflavin from Streptomyces davawensis are metabolized by human flavokinase and human FAD synthetase.
December 2011, Biochemical pharmacology,
Y Yamada, and A H Merrill, and D B McCormick
Induction of the FAD synthetase system in rat liver by phenobarbital administration.
January 1979, International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition,
Y Yamada, and A H Merrill, and D B McCormick
Affinity chromatographic purification and properties of flavokinase (ATP:riboflavin 5'-phosphotransferase) from rat liver.
February 1980, The Journal of biological chemistry,
Y Yamada, and A H Merrill, and D B McCormick
Purification and characterization of FAD synthetase from Brevibacterium ammoniagenes.
December 1986, The Journal of biological chemistry,
Y Yamada, and A H Merrill, and D B McCormick
Structural analysis of FAD synthetase from Corynebacterium ammoniagenes.
September 2008, BMC microbiology,
Copied contents to your clipboard!