Introduction: Coagulation factor X is an important protein in the blood coagulation pathway. It contains significant structural features that affect its function. The purpose of this study was to investigate the structural-functional features of activated form of Factor X in the presence of calcium ions. Factor X consists of 4 domains. Gamma-carboxyl glutamic acid (GLA) domain contains negatively charged and hydrophobic amino acids. These two amino acid groups with contrasting characteristics are responsible for binding to calcium ions and the membrane respectively, so it provides appropriate folding of Factor X in the presence of calcium ions. Epidermal growth factor-like domain (Epidermal growth Factor) which includes EGF1 and EGF2, is the edge between GLA and serine protease domain (SP) and it is involved in binding calcium.

Methods: Gathering and collecting of data has been done from molecular research in this area. It includes descriptions of three-dimensional structural characteristics of the Factor X.

Conclusion: The catalytic role of Factor X is performed by SP domain which made the heavy chain of factor X. Amino acids of SP domain play role in binding factor X to different activator and inhibitor.