Results 131 to 140 of about 8,906,109 (167)

Vitamin K epoxide reductase: Evidence that Vitamin K dihydroquinone is a product of Vitamin K epoxide reduction

Biochemical and Biophysical Research Communications, 1981
Abstract Vitamin K epoxide reductase is a two component enzyme activity which catalyzes the reduction of Vitamin K epoxide using dithiothreitol as either a primary or secondary source of reducing equivalents. A high performance liquid chromatographic assay system indicates that in addition to the quinone, the dihydroquinone form of Vitamin K is a ...
P A, Sherman, E G, Sander
openaire   +2 more sources

Lapachol inhibition of vitamin K epoxide reductase and vitamin K quinone reductase

Archives of Biochemistry and Biophysics, 1984
Lapachol [2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone] has been shown to be a potent inhibitor of both vitamin K epoxide reductase and the dithiothreitol-dependent vitamin K quinone reductase of rat liver microsomes in vitro. These observations explain the anticoagulant activity of lapachol previously observed in both rats and humans.
P C, Preusch, J W, Suttie
openaire   +2 more sources

Identification of the gene for vitamin K epoxide reductase

Nature, 2004
Vitamin K epoxide reductase (VKOR) is the target of warfarin, the most widely prescribed anticoagulant for thromboembolic disorders. Although estimated to prevent twenty strokes per induced bleeding episode, warfarin is under-used because of the difficulty of controlling dosage and the fear of inducing bleeding. Although identified in 1974 (ref.
Tao, Li, Chun-Yun, Chang, Da-Yun, Jin, Pen-Jen, Lin, Anastasia, Khvorova, Darrel W, Stafford   +5 more
openaire   +2 more sources

Zebrafish vitamin K epoxide reductases: expression in vivo, along extracellular matrix mineralization and under phylloquinone and warfarin in vitro exposure

Fish Physiology and Biochemistry, 2015
15 páginas, 5 figuras, 1 tabla.Vitamin K (VK) acts as a cofactor driving the biological activation of VK-dependent proteins and conferring calcium-binding properties to them.
Vincent Laize, Parameswaran Vijayakumar, Fernández I   +2 more
exaly   +2 more sources

VKORC1L1, an Enzyme Rescuing the Vitamin K 2,3-Epoxide Reductase Activity in Some Extrahepatic Tissues during Anticoagulation Therapy

Journal of Biological Chemistry, 2013
Vitamin K is involved in the -carboxylation of the vitamin K-dependent proteins, and vitamin K epoxide is a by-product of this reaction. Due to the limited intake of vitamin K, its regeneration is necessary and involves vitamin K 2,3-epoxide reductase ...
Abdessalem Hammed, Virginie Lattard, Etienne Benoit   +2 more
exaly   +2 more sources

Sulfaquinoxaline inhibition of vitamin K epoxide and quinone reductase

Archives of Biochemistry and Biophysics, 1989
Sulfaquinoxaline (N1-(2-quinoxalinyl)sulfanilamide) has been shown to be a potent (Ki = 1 microM) freely reversible inhibitor of the dithiothreitol-dependent reduction of both vitamin K epoxide and vitamin K quinone by rat liver microsomes in vitro. This observation provides an explanation for the hemorrhagic syndrome occasionally seen in poultry on ...
P C, Preusch, S E, Hazelett, K K, Lemasters   +2 more
openaire   +2 more sources

Structure and Function of Vitamin K Epoxide Reductase

2008
Vitamin K epoxide reductase (VKOR) is an integral membrane protein that catalyzes the reduction of vitamin K 2,3-epoxide and vitamin K to vitamin K hydroquinone, a cofactor required for the gamma-glutamyl carboxylation reaction. VKOR is highly sensitive to inhibition by warfarin, the most commonly prescribed oral anticoagulant.
Jian-Ke, Tie, Darrel W, Stafford
openaire   +2 more sources

Studies of the Vitamin K-Dependent Carboxylase and Vitamin K Epoxide Reductase in Rat Liver

Haemostasis, 2009
Vitamin K is required as a cofactor for a microsomal enzyme that converts glutamyl residues in precursor proteins to γ-carboxyglutamyl residues in completed proteins. These residues are essential for the biological function of prothrombin, factors VII, IX, and X, protein C, and protein S.
J W, Suttie, P C, Preusch
openaire   +2 more sources

Vitamin K epoxide reductase expression and prostate cancer risk

Urologic Oncology: Seminars and Original Investigations, 2017
Increasing evidence has demonstrated that men taking the anticoagulant warfarin have a lower risk of developing prostate cancer. This phenomenon is not observed in other cancers. We sought to determine if the target of warfarin, vitamin K epoxide reductase (VKOR), is expressed in benign and cancerous prostate tissues and if a functional single ...
Ben Yi, Tew, Sumanta K, Pal, Miaoling, He, Tommy, Tong, Huiqing, Wu, JoAnn, Hsu, Xueli, Liu, Susan L, Neuhausen, Jeremy O, Jones   +8 more
openaire   +2 more sources

Microsomal warfarin binding and vitamin K 2,3-epoxide reductase

Biochemical Pharmacology, 1989
Rat liver microsomal 4-hydroxycoumarin binding was studied by assaying specific [14C]warfarin binding. Microsomes of warfarin-sensitive rats contained about 40 pmole of specific binding sites per mg of microsomal protein. There was no difference for R- or S-[14C]warfarin.
H H, Thijssen, L G, Baars
openaire   +2 more sources