The Role of Bovine High-Molecular-Weight (HMW) Kininogen in Contact-Mediated Activation of Bovine Factor XII: Interaction of HMW Kininogen with Kaolin and Plasma Prekallikrein12

Abstract

Previous studies from our laboratories (Sugo et al. (1980) Biochemistry 19, 3215-3220) have shown that bovine high-molecular-weight (HMW) kininogen remarkably accelerates the kaolin-mediated activation of Factor XII in the presence of prekallikrein, and that both fragment 1.2 and the light chain regions located in the COOH terminal half of the kininogen molecule are essential for the activation. In the present study, we demonstrate that the accelerating effect of HMW kininogen is mediated through its adsorption on the kaolin surface through the fragment 1.2 region and its complex formation with prekallikrein through the light chain region. The evidence is as follows: 1. HMW kininogen radio-labeled with 125I was adsorbed on kaolin and the adsorption was inhibited by the prior treatment of kaolin with fragment 1.2, fragment 1.2-light chain, kinin-free protein or HMW kininogen, but not with kinin- and fragment 1.2-free protein, light chain or low molecular-weight (LMW) kininogen. 2. The complex formation of HMW kininogen with prekallikrein in bovine plasma or in the purified system was examined by gel-filtration on a column of Sephacryl S-200 In bovine plasma, prekallikrein was eluted in the same fraction as HMW kininogen, showing an apparent molecular weight of 250,000, whereas purified prekallikrein was eluted in the fraction corresponding to an apparent molecular weight of 100,000. When purified prekallikrein was mixed with purified HMW kininogen in a mol ratio of 1 to 2, all prekallikrein was found to be associated with HMW kininogen. Furthermore, purified prekallikrein mixed with kininogen derivatives, such as kinin- and fragment 1.2-free protein, fragment 1.2-light chain or light chain, was eluted in the higher molecular weight fraction. HMW kininogen did not form a complex with prekallikrein. Using the same technique, it was shown that kinin- and fragment 1.2-free protein forms a complex not only with prekallikrein but also with kallikrein.

The sequence HGLGHGHEQQHGLGHGH in the light chain of high molecular weight kininogen serves as a primary structural feature for zinc‐dependent binding to an anionic surface

“…Moreover, in plasma where Zn2+ is present at 20 pM (Braunwald, 1987), the peptide is equally inhibitory toward the coagulant activity of HK with or without added zinc. Our data that HK binding to kaolin is independent of Zn2+, which agrees with Ikari et al (1981) and suggests that the Zn2+ dependence of the heptadecapeptide probably is due to facilitation of proper folding rather than to an effect on the direct interaction with kaolin. However, kaolin is an artificial anionic model surface.…”

“…When bovine HK is digested with bovine kallikrein, a polypeptide was removed from the light chain corresponding to the histidine-glycine-rich domain of human HK (Han et al, 1976;Sugo et al, 1980;Ikari et al, 1981), which results in both the loss of coagulant activity and ability of cleaved bovine HK to bind to negatively charged surfaces. In human HK, unlike bovine HK, there is a substitution of Lys at position 402 for Arg that results in failure of human plasma kallikrein, which prefers arginine residues, to cleave the corresponding peptide from human HK.…”

“…Therefore, no loss of activity occurs when human plasma kallikrein hydrolyzes human HK. Chemical modification studies by Ikari et al (1981) and Retzios et al (1987) indicate that histidine residues of bovine and human HK, respectively, are involved in the interaction of the molecule with negatively charged surfaces.…”

Granulocyte elastase cleaves human high molecular weight kininogen and destroys its clot-promoting activity.

“…Effect of Granulocyte Elastase on Clot-promoting Activity of HMWKininogen. The domain of the HMW kininogen molecule responsible for its clot-promoting activity is in the light chain and is distinct from the kinin-containing region (24)(25)(26)(27) test the effect of granulocyte elastase upon the clot-promoting property of HMW kininogen, elastase in amounts of 0.02-0.64 ttg was incubated with each ml of either normal plasma or of purified HMW kininogen (95 gg) . Then, the specific clotpromoting activity attributable to HMW kininogen was quantified by measuring the effects ofdilutions of these incubation mixtures upon the clotting time of plasma from a person with a severe hereditary deficiency of plasma kininogens (12).…”

“…M. x 10 -3 are shown on the right. (26,27), may have been digested, for kaolin was used in the assay to measure HMW kininogen coagulant activity. These studies do not define the points of elastase cleavage .…”