Kininogens are multidomain glycoproteins found in the blood of most vertebrates. High molecular weight
kininogen demonstrate both carrier and co-factor activity as part of the intrinsic pathway of coagulation, leading to thrombin generation. Kininogens are the source of the vasoactive nonapeptide bradykinin. To date, attempts to crystallize
kininogen have failed, and very little is known about the shape of
kininogen at an atomic level. New advancements in the field of cryo-electron microscopy (cryoEM) have enabled researchers to crack the structure of proteins that has been refractory to traditional crystallography techniques. High molecular weight
kininogen is a good candidate for structural investigation by cryoEM. The goal of this
review is to summarize the findings of
kininogen structural studies.