Biomaterial Database

Inhibition of (Na+, K+)adenosine triphosphatase and its partial reactions by quercetin. 1976

Y Kuriki, and E Racker

The bioflavonoid, quercetin, inhibited the (Na+, K+)adenosine triphosphatase purified from the electric organ of electric eel (Electrophorus electricus) or from lamb kidney. An analysis of its mode of action revealed that the formation of phosphoenzyme from Pi but not from ATP was inhibited. Quercetin increased the amount of ADP-sensitive phosphoenzyme (E1--P), indicating an inhibition of the conversion of E1--P to the ADP-insensitive form (E2--P). The rate of dephosphorylation of the phosphoenzyme formed from ATP was slowed by quercetin. These results suggest that quercetin inhibits the formation of E2--P from either Pi or E1-P as well as the hydrolysis of the phosphoenzyme. Its mode of action is therefore different from that of ouabain and other inhibitors of the Na+, K+)adenosine triphosphatase.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
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
D011794	Quercetin	A flavonol widely distributed in plants. It is an antioxidant, like many other phenolic heterocyclic compounds. Glycosylated forms include RUTIN and quercetrin.	3,3',4',5,7-Pentahydroxyflavone,Dikvertin
D004557	Electric Organ	In about 250 species of electric fishes, modified muscle fibers forming disklike multinucleate plates arranged in stacks like batteries in series and embedded in a gelatinous matrix. A large torpedo ray may have half a million plates. Muscles in different parts of the body may be modified, i.e., the trunk and tail in the electric eel, the hyobranchial apparatus in the electric ray, and extrinsic eye muscles in the stargazers. Powerful electric organs emit pulses in brief bursts several times a second. They serve to stun prey and ward off predators. A large torpedo ray can produce of shock of more than 200 volts, capable of stunning a human. (Storer et al., General Zoology, 6th ed, p672)	Electric Organs,Organ, Electric,Organs, Electric
D004593	Electrophorus	A genus of fish, in the family GYMNOTIFORMES, capable of producing an electric shock that immobilizes fish and other prey. The species Electrophorus electricus is also known as the electric eel, though it is not a true eel.	Eel, Electric,Electric Eel,Electrophorus electricus
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations
D005419	Flavonoids	A group of phenyl benzopyrans named for having structures like FLAVONES.	2-Phenyl-Benzopyran,2-Phenyl-Chromene,Bioflavonoid,Bioflavonoids,Flavonoid,2-Phenyl-Benzopyrans,2-Phenyl-Chromenes,2 Phenyl Benzopyran,2 Phenyl Benzopyrans,2 Phenyl Chromene,2 Phenyl Chromenes
D000251	Adenosine Triphosphatases	A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.	ATPases,Adenosinetriphosphatase,ATPase,ATPase, DNA-Dependent,Adenosine Triphosphatase,DNA-Dependent ATPase,DNA-Dependent Adenosinetriphosphatases,ATPase, DNA Dependent,Adenosinetriphosphatases, DNA-Dependent,DNA Dependent ATPase,DNA Dependent Adenosinetriphosphatases,Triphosphatase, Adenosine
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