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At least 19 recordsLinked to original sources
PubMed1992

Immunological characterization of rat kininogens with monoclonal antibodies to T-kininogen. Distinction between the different domains of T-kininogen and the multiple rat kininogens.

A panel of 16 monoclonal antibodies (mAb) were produced against rat T-kininogen to characterize this family of proteins. These mAbs bound 125I-T-kininogen by radioimmunoassay as well as reacting strongly with immobilized T-kininogen in an enzyme-linked immunosorbent assay (ELISA). The reactivity of these antibodies with proteolytic fragments of T-kininogen demonstrated the recognition of several different epitopes. One antibody was specific for the domain 1 of the heavy chain and/or the light chain, twelve antibodies were specific for domain 2 and three antibodies were specific for domain 3. All monoclonal antibodies recognized the two forms of T-kininogen encoded by the two different T-kininogen genes, TI and TII kininogen, except antibody TK 16-3.1 which uniquely reacted with TII kininogen. Two antibodies recognizing domain 2 cross-reacted with the high-molecular-mass kininogen (H-kininogen), whereas all the other monoclonal antibodies were specific to T-kininogen and did not recognize the heavy chain of H-kininogen. None of the antibodies tested altered the thiol protease inhibitory activity of T-kininogen, its partial proteolysis by rat mast cell chymase or the hydrolysis of H-kininogen by rat urinary kallikrein. The use of these antibodies in the development of sensitive ELISA to measure T-kininogen levels in plasma, urine, liver microsomes and hepatocytes is described. Two different forms of T-kininogen were distinguished by these monoclonal antibodies in Western blotting using rat plasma. The localization of T-kininogen was defined using these monoclonal antibodies by immunohistochemistry in rat liver hepatocytes and rat kidney.

Animals↗
PubMed1988

The high-molecular-mass kininogen deficient rat expresses all kininogen mRNA species, but does not export the high-molecular-mass kininogen synthesized.

The Katholiek substrain of Brown Norway (BN/Kat) rats exhibits a very low level of circulating high-molecular-mass (HMW) kininogen and a partial deficiency in plasma prekallikrein. Northern blot analysis of liver RNA revealed that HMW kininogen and prekallikrein mRNAs are present in these rats with a similar size and abundance compared to control Brown Norway (BN/Orl) rats. The low-molecular-mass kininogen mRNA, encoded by the same kininogen gene as HMW kininogen mRNA by alternative splicing, is detected in both strains by dideoxynucleotide limited primer extension analysis. Measurement of HMW kininogen by radioimmunoassay was performed in liver subcellular fractions. It reveals that, in contrast to its absence in the cytosolic fraction, HMW kininogen in deficients rats is slightly more abundant in the microsomal fraction, than in control rats. These observations exclude both an abnormality at the level of gene transcription and a major structural modification of the transcribed RNA and of the synthesized HMW kininogen. They favour the hypothesis of an abnormal intracellular transport of the HMW kininogen in deficient rats.

Animals↗
PubMed1988

Hydroxyprolyl3-bradykinin in high molecular mass kininogen. Presence in human and monkey kininogens, but not in kininogens from bovine, rat, rabbit, guinea pig and mouse plasmas.

The contents of hydroxyprolyl3-bradykinin in high molecular mass (HMM) kininogens from human and animal plasmas were examined by reversed-phase HPLC following their proteolytic scission by bovine plasma kallikrein. The relative contents of hydroxyprolyl3-bradykinin in kinins from HMM kininogens from pooled plasmas of human and monkey origin were 33 and 73%, respectively. On the other hand, hydroxyprolyl3-bradykinin could not be detected in HMM kininogen preparations from bovine, rat, guinea pig, rabbit and mouse plasmas. Hydroxyproline in hydroxyprolyl3-bradykinin was assigned as trans-4-hydroxyproline by comparison of the retention times on reversed-phase HPLC with isomers of hydroxyproline after derivatization with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole chloride.

Amino Acid Sequence↗
PubMed1987

Direct radioimmunoassay for rat high molecular weight kininogen. Measurement of immunoreactive high molecular weight kininogen in normal and kininogen deficient plasma.

A direct radioimmunoassay (RIA) for rat high molecular weight kininogen (HMW Kg) was developed that enabled us to detect 71 fmol/ml of HMW Kg. The antibodies did not crossreact in the RIA with up to 5 nmol of purified rat alpha 1 cysteine proteinase inhibitor (T-kininogen). When various quantities of pure HMW Kg were either quantified by the RIA or by the measurement of kinin contents determined after trypsin hydrolysis, identical values were obtained by both methods. This RIA allowed the measurement of HMW Kg in 0.015 to 1 microliter of rat plasma. HMW Kg levels in plasma of Wistar rats and in Brown Norway rats of the Orlean Strain (BN/Orl) were 1.52 +/- 0.05 (n = 6) and 2.050 +/- 0.015 (n = 8) nmol/ml respectively. In the Brown Norway rats of the Katholiek strain (BN/Kat) that are considered to be deficient in HMW Kg, immunoreactive HMW Kg levels were less than 2% of those of the BN/Orl rats. These results confirm that the BN/Kat animals have a molecular defect in HMW Kg.

Animals↗
PubMed1988

Purification and characterization of rat T-kininogens isolated from plasma of adjuvant-treated rats. Identification of three kinds of T-kininogens.

Two T-kininogens (TI- and TII-kininogens) found in plasma of Freund's adjuvant-treated rats were purified by several chromatographic procedures. The isolated TI- and TII-kininogens showed different mobilities on polyacrylamide gel electrophoresis in the absence of sodium dodecyl sulfate, but were indistinguishable in the presence of sodium dodecyl sulfate. They were also indistinguishable in amino acid composition and antigenicity, but differed in sialic acid content. The NH2- and COOH-terminal sequences were determined. In the 30 NH2-terminal residues, 2 were different. The kinin regions in the COOH-terminal portions of the two kininogens have sequences that demonstrate TI-kininogen contains a mixture of two kinin-containing regions, with substitution of 4 amino acid residues, one of which is identical to the COOH-terminal portion of alpha 1-major acute phase protein (Cole, T., Inglis, A. S., Roxburgh, C. M., Howlett, G. J., and Schreiber, G. (1985) FEBS Lett. 182, 57-61) and the other to the COOH-terminal portion of TI-kininogen (Furuto-Kato, S., Matsumoto, A., Kitamura, N., and Nakanishi, S. (1985) J. Biol. Chem. 260, 12054-12059), both predicted from cDNA sequences. The amino acid sequence of the kinin-containing region from TII-kininogen is the same as the COOH-terminal portion of TII-kininogen predicted from the cDNA. These results indicate that T-kininogens from the plasma of adjuvant-treated rats consist of a family of kininogens, that is, TI- and TII-kininogens (separable on DEAE-Sephadex A-50), and that TI-kininogen consists of at least two variants (TI alpha and TI beta) which correspond to the alpha 1-major acute phase protein reported by Cole et al. and TI-kininogen reported by Furuto-Kato et al., respectively. Immunoblotting studies with plasmas from non-inflamed and adjuvant-treated rats also indicate that T-kininogen which was previously isolated from non-inflamed rat plasma corresponds to TI-kininogen and that TII-kininogen is newly generated after treatment of rats with adjuvants.

Adjuvants, Immunologic↗
PubMed1977

Prekallikrein deficiency in a kindred with kininogen deficiency and Fitzgerald trait clotting defect. Evidence that high molecular weight kininogen and prekallikrein exist as a complex in normal human plasma.

Plasma from an individual with a hereditary deficiency of kininogens is deficient in kininogen antigens; heterozygous relatives are partially deficient in plasma kininogen antigens. In addition, plasma from the proband is partially deficient in functional and antigenic properties of a plasma prekallikrein, and the relatives heterozygous for kininogen deficiency are also partially deficient in the plasma prekallikrein. It is possible that the defects are both inherited and that the inheritance of a deficiency of prekallikrein is genetically linked to the inheritance of a deficiency of kininogen. Alternatively, it is possible that the deficiency of prekallikrein may be due to its hypercatabolism which could be a consequence of a deficiency of high molecular weight kininogen that may stabilize the prekallikrein in plasma. Evidence to support this possibility is presented by the fact that prekallikrein and high molecular weight kininogen apparently exist as a complex in normal plasma, because monospecific antiserum to kininogen removed both high molecular weight kininogen and prekallikrein from plasma, and vice versa. Moreover, prekallikrein was not adsorbed from kininogen-deficient plasma by antiserum to kininogen unless high molecular weight kininogen was first added to the plasma. Low molecular weight kininogen did not participate in these reactions.

Blood Coagulation↗
PubMed1981

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 prekallikrein.

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.

Adsorption↗
PubMed1985

Protein-protein interactions in contact activation of blood coagulation. Binding of high molecular weight kininogen and the 5-(iodoacetamido) fluorescein-labeled kininogen light chain to prekallikrein, kallikrein, and the separated kallikrein heavy and light chains.

Binding of the 5-(iodoacetamido)fluorescein (IAF)-labeled high molecular weight (HMW) kininogen light chain to prekallikrein and D-Phe-Phe-Arg-CH2Cl-inactivated kallikrein was monitored by a 0.040 +/- 0.002 increase in fluorescence anisotropy. Indistinguishable average dissociation constants and stoichiometries of 14 +/- 3 nM and 1.1 +/- 0.1 mol of prekallikrein/mol of IAF-light chain and 17 +/- 3 nM and 0.9 +/- 0.1 mol of kallikrein/mol of IAF-light chain were determined for these interactions at pH 7.4, mu 0.14 and 22 degrees C. Prekallikrein which had been reduced and alkylated in 6 M guanidine HCl lost the ability to increase the fluorescence anisotropy of the IAF-kininogen light chain, suggesting that the native tertiary structure was required for tight binding. The kallikrein heavy and light chains were separated on the basis of the affinity of the heavy chain for HMW-kininogen-Sepharose, after mild reduction and alkylation of kallikrein under nondenaturing conditions. Under these conditions, alkylation with iodo [14C]acetamide demonstrated that only limited chemical modification had occurred. Binding of the IAF-kininogen light chain to the isolated alkylated kallikrein heavy chain, when compared to prekallikrein and kallikrein, was characterized by an indistinguishable increase in fluorescence anisotropy, average dissociation constant of 14 +/- 3 nM, and stoichiometry of 1.2 +/- 0.1 mol of kallikrein heavy chain/mol of IAF-light chain. In contrast, no binding of the D-Phe-Phe-Arg-CH2Cl-inactivated kallikrein light chain was detected at concentrations up to 500 nM. Furthermore, 300 nM kallikrein light chain did not affect IAF-kininogen light chain binding to prekallikrein, kallikrein, or the kallikrein heavy chain. The binding of monomeric single chain HMW-kininogen to prekallikrein, kallikrein, and the kallikrein heavy and light chains was studied using the IAF-kininogen light chain as a probe. Analysis of the competitive binding of HMW-kininogen gave average dissociation constants and stoichiometries of 12 +/- 2 nM and 1.2 +/- 0.1 mol of prekallikrein/mol of HMW-kininogen, 15 +/- 2 nM and 1.3 +/- 0.1 mol of kallikrein/mol of HMW-kininogen, 14 +/- 3 nM and 1.4 +/- 0.2 mol of kallikrein heavy chain/mol of HMW-kininogen, and no detectable effect of 300 nM kallikrein light chain on these interactions. We conclude that a specific, nonenzymatic interaction between sites located exclusively on the light chain of HMW-kininogen and the heavy chain of kallikrein or prekallikrein is responsible for the formation of 1:1 noncovalent complexes between these proteins.

Binding, Competitive↗
PubMed1981

Studies on human high molecular weight (HMW) kininogen. III. Cleavage of HMW kininogen by the action of human salivary kallikrein.

Human high molecular weight (HMW) kininogen is a single chain with a molecular weight of 120,000 and is cleaved by plasma kallikrein sequentially into a nicked kininogen, an intermediate kinin-free protein (KFP-I), and a stable KFP-II. Here we report a study into the process of cleavage of human HMW kininogen by human salivary kallikrein. On incubation with salivary kallikrein, HMW kininogen was first converted into a nicked kininogen composed of disulfide-linked chains of 62,000 and 56,000 daltons. Subsequently, the nicked kininogen was cleaved into kinin and a KFP, which was apparently of equal size to the nicked kininogen, that is, KFP-I. In contrast to plasma kallikrein, salivary kallikrein did not cleave KFP-I into KFP-II. The two chains were separated by SP-Sephadex C-50 chromatography of reduced and alkylated KFP-I. The N-termini of HMW kininogen and the 62,000-daltons chain were found to be pyroglutamyl-isoleucyl, while that of the 56,000-daltons chain was found to be serine. These results indicate that the sequence of the two chains and kinin in human HMW kininogen is 62,000-daltons chain-kinin-56,000-daltons chain from the N-terminal end of HMW kininogen. Possible processes of cleavage of human HMW kininogen by human plasma and salivary kallikreins are also discussed.

Humans↗
PubMed1979

Studies on human kininogens. I. Isolation, characterization, and cleavage by plasma kallikrein of high molecular weight (HMW)-kininogen.

1. Human high molecular weight (HMW)-kininogen was highly purified from human plasma by chromatographies on QAE-Sephadex A-50 and CM-Sephadex C-50. Human HMW-kininogen thus purified was a mixture of a single chain and a disulfide-linked pair of chains. Human HMW-kininogen is an acidic glycoprotein having a molecular weight of 120,000. The amino acid composition of human HMW-kininogen is quite similar to that of bovine HMW-kininogen. 2. We investigated whether the liberation of kinin from human HMW-kininogen by human plasma kallikrein was accompanied by liberation of histidine-rich fragments, as observed with bovine HMW-kininogen (Han et al. (1975) J. Biochem. 77, 55--68). After prolonged incubation of human HMW-kininogen and human plasma kallikrein followed by gel-filtration on Sephadex G-50, a fragment of molecular weight 8,000 was isolated together with bradykinin. However, the histidine content of the fragment was not as high as that in the bovine fragments. Most of the histidine in human HMW-kininogen was recovered in the kinin-free protein, and the light chain of kinin-free protein was found to be rich in histidine compared with the heavy chain. These results suggest that the histidine-rich sequence in human HMW-kininogen is not released by the action of human plasma kallikrein, but remains bound to the light chain of kinin-free protein.

Amino Acids↗
PubMed1981

Studies on human high molecular weight (HMW) kininogen. II. Structural change of HMW kininogen by the action of human plasma kallikrein.

We have investigated in detail the cleavage of human high molecular weight (HMW) kininogen by human plasma kallikrein and revealed the formation of a nicked kininogen and a novel kinin-free protein (KFP) as intermediate cleavage products. The cleavage of a single chain HMW kininogen (Mr=120,000) by plasma kallikrein was a three-step reaction. The first cleavage yielded a nicked kininogen composed of two disulfide-linked 62,000 and 56,000 daltons chains. The second cleavage yielded kinin and an intermediate kinin-free protein, KFP-I, which was apparently of equal size to the nicked kininogen. The third cleavage yielded a stable kinin-free protein, KFP-II, composed of two disulfide-linked 62,000 and 45,000 daltons chains. The liberation of an 8,000 daltons fragment was identified when the 56,000 daltons chain isolated by SP-Sephadex C-50 chromatography of reduced and alkylated KFP-I was cleaved by plasma kallikrein into the 45,000 daltons chain. Although the antiserum against HMW kininogen cross-reacted with low molecular weight (LMW) kininogen, the antiserum against the 45,000 daltons chain was specific for HMW kininogen. These results suggest that the antigenic determinant groups common to HMW and LMW kininogens are located in the 62,000 daltons heavy chain, while those specific for HMW kininogen are located in the 45,000 daltons light chain, which is known to retain blood coagulation activity.

Chemical Phenomena↗
PubMed1987

Comparison of human high molecular weight kininogen digestion by plasma kallikrein and by plasmin. A revised method of purification of high molecular weight kininogen.

Both kallikrein and plasmin readily released 112,000 and 102,000 molecular weight derivatives from purified human high molecular weight (HMW)-kininogen. In each instance, these early digestion products were composed of disulfide-linked chains of 64,000 and 58,000 molecular weights. Under the experimental conditions used, kallikrein failed to release additional cleavage fragments from HMW-kininogen when it had been previously digested by plasmin, whereas HMW-kininogen pretreated with kallikrein was then cleaved by plasmin into several derivatives of decreasing molecular size. The profound molecular changes induced by plasmin were only accompanied by partial kinin release. Plasmin cleavage dissociated procoagulant activity from at least one antigenic site of HMW-kininogen light chain. Moreover, kinin activity could be released from a cleavage product of HMW-kininogen containing light but not heavy chain antigens, indicating that plasmin had cleaved this kininogen on the N-terminal side of the bradykinin region of the molecule. Cleavage of HMW-kininogen by kallikrein readily released bradykinin, whereas kinin release by plasmin was slower and the cleavage pattern different. It is, therefore, unlikely that plasmin is a major source of bradykinin release in plasma. A method of isolating HMW-kininogen from human plasma is described that provides a homogeneous single band of kininogen, with a recovery of approximately 44% with respect to that in plasma in a period of 5 days.

Chromatography↗
PubMed1979

Plasma high molecular weight kininogen concentration in health and in chosen impairments of haemostasis. Evidence that plasmin uncovers a new antigenic site in high molecular weight kininogen.

High molecular weight kininogen (HMW-kininogen) concentration was measured in the plasma of healthy blood donors, patients with haemophilia A, idiopathic thrombocytopoenic purpura, deep vein thrombosis treated with oral anticoagulants and patients treated with streptokinase (SK). The concentration of HMW-kininogen in the plasma of healthy subjects was 92 +/- 15 micrograms/ml. The values obtained in patients' plasma were not different statistically. In the plasma of patients treated with repeated infusion of SK, a significant increase of HMW-kininogen antigen activity was noted after each injection of the drug. Similar results were obtained when SK was added to plasma "in vitro" or when a purified preparation of HMW-kininogen was treated with plasmin. These and additional data obtained suggest that plasmin uncovers in the HMW-kininogen molecule a new antigenic site(s) common to HMW-kininogen and low molecular weight kininogen and new antigenic site(s) specific only for HMW-kininogen.

Absorption↗
PubMed1985

T-kininogen--the major plasma kininogen in rat adjuvant arthritis.

Total kininogen in plasma of Freund's adjuvant treated rats increased 20-fold 7 days following the injection. Analysis of the kininogens demonstrated that increases in T-kininogen was the major reason for the rise in kininogen. High molecular weight and low molecular weight kininogens showed little or no change. The increase in T-kininogen paralleled the inflammatory condition. Anti-inflammatory agents which reduced paw swelling also reduced plasma T-kininogen levels. Unidentified peaks on HPLC of kinin following plasma treatment by trypsin were shown to be oligopeptides containing T-kinin (Ile-serbradykinin). The relationship of T-kininogen to the inflammatory response is discussed.

Animals↗
PubMed1976

Flaujeac factor deficiency. Reconstitution with highly purified bovine high molecular weight-kininogen and delineation of a new permeability-enhancing peptide released by plasma kallikrein from bovine high molecular weight-kininogen.

Flaujeac trait is the functional deficiency of a plasma protein of the intrinsic coagulation, kinin-forming, and plasma fibrinolytic pathways. The Flaujeac factor in man has been isolated and tentatively identified as a kininogen of high molecular weight (HMW). Highly purified bovine HMW-kininogen, but not bovine low molecular weight kininogen, repaired Flaujeac factor deficiency. The two subspecies of this molecule, HMW-kininogen a and HMW-kininogen b, also corrected Flaujeac factor deficiency. When bovine HMW-kininogen was incubated with bovine plasma kallikrein, kinin-free HMW-kininogen, bradykinin, and a glycopeptide fragment (peptide 1-2; 12,584 daltons) were rapidly released. None of these fragmentation products corrected Flaujeac factor deficiency alone or in mixtures. The function of HMW-kininogen appeared to depend upon the structural integrity of the native molecule. When injected in concentrations of 2 pmol-8 nmol/0.1 ml, peptide 1-2 caused increased vascular permeability in rabbits, rats, or guinea pigs. The enhanced permeability was maximal within 1-2 min and terminated in 5-10 min, differing from that of bradykinin or histamine. Injected together in equimolar amounts, peptide 1-2 and bradykinin produced a synergistic permeability response which was immediate in onset as well as prolonged in duration. Peptide 1-2 is a rapidly acting, highly basic glyco-peptide which mediates increased vascular permeability in a complementary and synergistic manner with bradykinin.

Animals↗
PubMed1981

High-molecular-weight kininogen from horse plasma. Isolation, characterization and comparison with bovine high-Mr kininogen.

High-molecular-weight (high-Mr) kininogen was purified from horse plasma by chromatography on columns of DEAE-Sephadex A-50, CM-Sephadex C-50, p-chlorobenzylamine-Sepharose and Sephadex G-150. The yield was about 150 mg from 81 of fresh plasma. The purified material gave a single band on sodium dodecylsulfate/polyacrylamide gel electrophoresis and a single precipitin line on immunodiffusion and immunoelectrophoresis. The molecular weight of horse high-Mr kininogen was estimated to be 78000 by dodecylsulfate gel electrophoresis using the Ferguson plot. Its polypeptide content was determined to be 86% by amino acid analysis and there was a total of 581 amino acid residues/molecule of protein. The kininogen contained a total of 13.9% carbohydrates, consisting of hexoses (7.8%), glucosamine (1.9%), galactosamine (0.6%) and sialic acid (3.6%). On incubation of horse high-Mr kininogen with bovine and horse plasma kallikreins, several fragments which contained extremely high levels of histidine, were liberated, in addition to kinin. After the liberation of kinin and histidine-rich fragments, a protein free of kinin and its fragments was isolated. This protein consisted of two polypeptide chains, heavy chain and light chain, which are bridged by disulfide bonds. The molecular weight and amino acid composition of the heavy chain and the light chain from horse high-Mr kininogen were very similar to those of the heavy and light chains from bovine high-Mr kininogen, respectively. From these results, it was revealed that horse high-Mr kininogen is quite similar to bovine high-Mr kininogen in terms of their physicochemical and chemical properties, although they are immunologically distinguishable.

Amino Acids↗
PubMed1985

Rat high-molecular-weight kininogen: purification, production of antibodies and demonstration of lack of immunoreactive kininogen in a strain of brown Norway rats.

High-molecular-weight kininogen was purified to apparent homogeneity from Wistar rat plasma by a two-steps chromatographic procedure. 3 mg of kininogen were obtained from 205 ml of plasma. The purified high-Mr kininogen had a bradykinin content of 10.2 micrograms bradykinin equivalents/mg protein. Under denatured and reduced conditions it gave a single band on polyacrylamide gel electrophoresis corresponding to an apparent molecular mass of 110 kDa. Antibodies obtained against rat high-Mr kininogen gave a single precipitation line when tested against rat plasma in double immunodiffusion and in crossed immunoelectrophoresis. Although rat high-Mr kininogen possesses physicochemical properties (molecular mass, kinin content per molecule and amino acid composition) similar to human high-Mr kininogen, its antibodies do not cross-react with human, monkey or rabbit plasma, indicating major interspecies differences in the structure of the molecule. Immunoreactive kininogen of Wistar rats was identical to that of Brown Norway rats from a strain bred in Orleans, France (BN/Orl). However, plasma from a strain of Brown Norway rats bred in Leuven, Belgium (BN/Kat), reported to be deficient in a kinin precursor (Damas, J. and Adam, A. (1980) Experientia 36, 586-587), did not contain immunoreactive material discernible by double immunodiffusion or crossed immunoelectrophoresis.

Amino Acids↗
PubMed1978

Characterization of human high molecular weight kininogen. Procoagulant activity associated with the light chain of kinin-free high molecular weight kininogen.

Human high molecular weight (HMW) kininogen has been isolated and was found to be a single chain protein of approximately equal to 120,000 daltons. Upon digestion with plasma kallikrein bradykinin is generated, and SDS gel electrophoresis of the kinin-free protein reveals an apparent loss in size of 15,000 daltons. The kinin-free kininogen retains full activity as a coagulation factor and consists of two chains: a heavy chain of approximately equal to 66,000 daltons disulfide-linked to a light chain of 37,000 daltons. The heavy chain of HMW kininogen shares antigenic determinants with LMW kininogen and possesses no detectable coagulant activity. The isolated light chain is shown to be responsible for the coagulant activity of HMW kininogen and contains a unique antigenic determinant that distinguishes HMW kininogen from low molecular weight kininogen.

Blood Coagulation Factors↗