HUMAN FACTOR XIII WITH CALCIUM BOUND IN THE ION SITE

Tryptophan 279 is Essential for the Transglutaminase Activity of Coagulation Factor XIII: Functional and Structural Characterization

Identification of the Calcium Binding Site and a Novel Ytterbium Site in Blood Coagulation Factor XIII by X-ray Crystallography

24% 1,2-propanediol, 100 mM sodium potassium phosphate buffer. To incorporate Calcium, the crystals were transferred to 24% 1,2-propanediol and MES buffer and soaked for 1-2 days in 90 mM CaCl2, pH 6.2, VAPOR DIFFUSION, temperature 294K

This entry is the further refinement of the 1ggu PDB coordinates (Fox et al, 1999). The crystals of this zymogen contain 90 mM CaCl2 and diffract to 2.0 A resolution. The changes to the 1ggu model include extension of the activation peptide of subunit 1 to the N-acetyl Ser at position 1, refitting of some residues, addition and deletion of water molecules, and insertion of alternate conformations for seven residues. The purpose for the further refinement is for comparison with the W279F mutant of factor XIII

Transglutaminase, blood coagulation, calcium, TRANSFERASE