spinqualitylabelsall models Structure of Closed Vitamin K Epoxide Reductase (PDB entry 6wv3) Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Contents 1 Introduction 1.1 Location of Enzyme 2 Structure 2.1 Transmembrane Helices 2.2 Cap Domain 3 Significant Cysteines 4 Vitamin K Epoxide 5 Warfarin

Introduction

Vitamin K Epoxide Reductase (VKOR) is an endoplasmic membrane enzyme that generates the active form of Vitamin K to support blood coagulation. The vitamin K Cycle, and the VKOR enzyme specifically are common drug targets for thromboembolic diseases. This is because, as pictured, the vitamin K cycle is the process in which blood coagulant factors II, VII, IX, and X are activated. This promotes blood clotting, which can be dangerous and cause thromboembolic diseases such as stroke, deep vein thrombosis, and/or pulmonary embolism.

Location of Enzyme

Vitamin K Epoxide Reductase is found and primarily synthesized in the liver. It is embedded in the membrane known as the endoplasmic reticulum.

Structure

VKOR WIKI The VKOR enzyme is made up of four transmembrane helices: T1, T2, T3, and T4.(Pictured in Grey) Each of these helices come together to form a hydrophobic pocket, that is topped by a cap domain. In the cap domain are important regions that are significant for Vitamin K binding, and the overall function of Vitamin K Epoxide Reductase. These important regions are the Anchor(Green), Cap Region (Blue), Beta Hairpin (Purple), and 3-4 Loop (Pink).

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Transmembrane Helices

Cap Domain

Significant Cysteines

Vitamin K Epoxide

Warfarin