The three-dimensional structures of several forms of the factor XIII A subunit have
been determined using single crystal x-ray diffraction methods. Our crystallographic
studies have provided the first detailed structural view of the factor XIII A subunit
and information that is useful for understanding transglutaminase function. We have
identified a conserved Cys314-His373-Asp396 catalytic triad of residues in the active
site of the molecule and a number of other conserved residues that may play important
roles as well. The calcium and strontium structures have revealed several conserved
acidic residues (Asp438, Glu485, and Glu490) involved in ion binding. We have also
been able to use our crystal structures as scaffolds to model the possible structural
effects of missense mutations that have been identified in factor XIII-deficient patients.
Factor XIII - transglutaminase - crystal structure - x-ray crystallography - catalytic
triad