Mapping of the discontinuous kininogen binding site of prekallikrein : A distal binding segment is located in the heavy chain domain A4
Prekallikrein, the precursor to the serine proteinase kailikrein, circulates in plasma in an equimolar complex with H-kininogen. The binding to H-kininogen is mediated by the kallikrein heavy chain consisting of four "apple" domains, A1-A4, which attaches to H-kininogen with high specificity and affinity (KD = 83 UM). At least two distinct portions of the kallikrein heavy chain form this H-kininog