We apologize for Proteopedia being slow to respond. For the past two years, a new implementation of Proteopedia has been being built. Soon, it will replace this 18-year old system. All existing content will be moved to the new system at a date that will be announced here.

Factor Xa

From Proteopedia

Revision as of 18:28, 24 April 2010 by Jacqueline Gertz (Talk | contribs)
Jump to: navigation, search

Contents

Introduction

Factor X is a vitamin K-dependent glycoprotein that is synthesized in the liver. Zymogen factor X circulates in plasma as a 2 chain molecule composed of a disulfide linked light chain (Mr = 16500) and heavy chain (Mr = 42,000). Factor X is activated to factor Xa by cleavage of the activation peptide. This reaction is catalyzed by factor VIIa-tissue factor (extrinsic Xase complex) and factor IXa-factor VIIIa (intrinsic Xase complex).[1]

Factor Xa, along with factor Va, calcium, and a phospholipid membrane surface form the prothrombinase complex, to cleave prothrombin to its active form, thrombin.

Structure

Enzyme Mechanism

General Serine Protease Mechanism

Related Enzymes

References

  1. Greer, John (2008). Wintrobe's Clinical Hematology, p. 545-546. Lippincott Williams & Wilkins. ISBN 0781765072.
Personal tools