PubMed Health⌕ Search

Biomedical subjects

K Enjyoji

Publications and source records attributed to K Enjyoji.

31 records · Page 2Linked to original sources

Hydroxylated kininogens and kinins.

Hydroxyprolyl-3-bradykinin was identified in the digest of purified human high molecular weight (H) kininogen with plasma kallikrein. Hydroxyproline was not detected in the heavy and light chains portions of H kininogen, although they include three possible sites for hydroxylation of proline by proline hydroxylase. The content of hydroxyprolyl-3-bradykinin in H kininogen from individual plasmas varied from 14% to 64% of total kinin. The present results and our previous results indicate that only kinin moity in H kininogen from human and monkey plasmas has been partially hydroxylated post-translationally by proline-4-hydroxylase.

Amino Acids↗

Purification and characterization of two isoforms of T-kininogens from rat liver microsomes.

T-Kininogen is one of the acute phase proteins, and is a precursor of T-kinin and a cysteine protease inhibitor. Two homologous T-kininogens (TI- and TII-kininogens) were isolated from microsomal fraction of inflamed rat liver, by chromatographies on columns of DEAE-Sepharose CL-6B and DEAE-5PW and by affinity chromatography on a column of anti T-kininogen monoclonal antibody. The amino terminal amino acid sequences of the two microsomal pyridylethylated T-kininogens after pyroglutamyl aminopeptidase treatment were identical with those of TI- and TII-kininogens from inflamed rat plasma. Microsomal T-kininogens moved faster on SDS-PAGE after treatment with endoglycosidase H. The amounts of microsomal TI- and TII-kininogens in inflamed and non-inflamed rat liver were quantitated by immunoblotting of homogenates of liver microsomes using anti T-kininogen rabbit antiserum. The amounts of microsomal T-kininogens were increased in inflamed rat liver, but the ratio of the amounts of TI-kininogen to TII-kininogen was not different in the inflamed and non-inflamed rat liver. On the other hand, TII-kininogen was not significantly detected in non-inflamed rat plasma. These results indicate that the secretion of one of the T-kininogens, TII-kininogen, into plasma may be prevented by some unknown mechanism.

Amino Acid Sequence↗

cDNA cloning and expression of rat tissue factor pathway inhibitor (TFPI).

Tissue factor pathway inhibitor (TFPI) is a factor Xa-dependent inhibitor for the factor VIIa-tissue factor complex. We isolated cDNA for rat TFPI by screening a lambda gt10 rat liver cDNA library. We determined the 1,228 bp nucleotide sequence, comprising a 88 bp 5' non-coding region, a 906 bp open reading frame, and a 234 bp 3' non-coding region, which encodes a protein of 302 amino acid residues. On Northern blot analysis of rat TFPI mRNA, rat TFPI mRNA was detected as two forms with different molecular sizes, 4.0 and 1.4 kb, which were expressed abundantly in heart, lung, kidney, and aortic endothelial cells. The homology of the amino acid sequence of rat TFPI with those of human and rabbit TFPI was found to be 60.7 and 57.4%, respectively. The lengths of the three tandem Kunitz-type inhibitor domains were strictly conserved not only among TFPI from the three species, but also among other proteins containing Kunitz-type inhibitor domains. The homology of the Kunitz-type domains in TFPI among the three species was 57, 86, and 69% in the 1st, 2nd, and 3rd domains, respectively. There was no significant difference in hydropathy profiles of TFPI from man, rabbit, and rat.

Amino Acid Sequence↗

Amino acid sequence and location of the disulfide bonds in bovine beta 2 glycoprotein I: the presence of five Sushi domains.

beta 2 glycoprotein I is a plasma protein with the ability to bind with various kinds of negatively charged substances. The complete amino acid sequence and the location of all the disulfide bonds of bovine beta 2 glycoprotein I were determined. Bovine beta 2 glycoprotein I consists of 326 amino acid residues with five asparagine-linked carbohydrate chains. Homology with the human protein was calculated to be 83%. Eleven disulfide bonds in bovine beta 2 glycoprotein I constitute four characteristic domains, Sushi domains, and one modified form of a Sushi domain.

Amino Acid Sequence↗

Characterization of rat factors X and Xa: demonstration of factor Xa in rat plasma.

We have found that rat plasma corrected the non-activated PT of human normal or factor-X deficient plasma, and the factor Xa-like activity being constantly detected in every 1 ml of blood collected via the cannulated carotid artery of rats. The present study was undertaken to characterize the factor Xa-like activity in rat plasma by preparing rat factor X and a monoclonal antibody against it. Factor X was purified from a BaCl2 eluate of rat plasma by chromatographies on columns of DEAE-Sepharose CL-6B and Sulfate Cellulofine or on a column of Affi-Gel 10 conjugated with a monoclonal antibody against rat factor X. Factor Xa-like activity in rat plasma was eliminated by the treatment of rat plasma with a monoclonal antibody which recognized the heavy chain portions of rat factors X and Xa. A kinetical study demonstrated that rat factor Xa was strongly inhibited by rat antithrombin III, with a Ki of 2.2 x 10(-11) M, in the presence of heparin. However, in the absence of heparin, the second order rate constant for the inhibition of rat factor Xa by rat antithrombin III was 2.6 x 10(4) M-1.min-1, which was one forty-third that for the inhibition of human factor Xa by human antithrombin III. Furthermore, rat factor Xa was resistant to the inhibition by rat alpha-1-antitrypsin and alpha-2-macroglobulin.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

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↗

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↗

Purification and characterization of two kinds of low molecular weight kininogens from rat (non-inflamed) plasma. One resistant and the second sensitive to rat glandular kallikreins.

Two kinds of low molecular weight kininogens (identified as A and B) were isolated from pooled plasma of Sprague-Dawley rats. They show a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the presence and absence of 2-mercaptoethanol, and the molecular weights are 68,000 for low Mr kininogen A and 73,000 for low Mr kininogen B. Although the molecular weights and amino acid compositions of the low Mr kininogens are similar, rat submaxillary and urinary kallikreins released bradykinin from low Mr kininogen B, whereas low Mr kininogen A was resistant to these enzymes. The COOH-terminal portion of low Mr kininogen A was isolated after cyanogen bromide treatment, and the amino acid sequence of the COOH-terminal 55 residues including the T-kinin (Ile-Ser-bradykinin) was determined. The COOH-terminal portion consists of two sequences with substitution of 4 residues. One peptide corresponds to 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 TI-kininogen predicted from a cDNA study (Furuto-Kato, S., Matsumoto, A., Kitamura, N., and Nakanishi, S. (1985) J. Biol. Chem. 260, 12054-12059). The results demonstrate that there exist at least two kinds of low Mr kininogens with clearly different function in rat plasma: one of them, low Mr kininogen A, is a precursor of T-kinin and is resistant to kallikreins, and the second, low Mr kininogen B, is sensitive to tissue kallikreins and shares properties with bovine and human low Mr kininogens. The results also demonstrate that T-kininogen is a mixture of two isoproteins which correspond to alpha 1-major acute phase protein or TI-kininogen, respectively. We could not detect the low Mr kininogen corresponding to the TII-kininogen predicted from the cDNA study of Furuto-Kato et al.

Amino Acid Sequence↗

Characterization of serine proteinases isolated from rat submaxillary gland: with special reference to the degradation of rat kininogens by these enzymes.

From the homogenate of rat submaxillary gland, two kinds of serine proteinases, named tentatively proteinases A and B, were isolated and their chemical properties and activities toward rat kininogens were examined, in comparison with those of submaxillary kallikrein. Proteinase A with Mr of 28,200 rapidly cleaved high-molecular-weight (HMW) kininogen into a protein of 67 kDa, which retained thiol-proteinase inhibitory activity, but had lost the correcting activity of HMW kininogen on the prolonged clotting time of Fitzgerald trait plasma. It liberated bradykinin from HMW kininogen but did not liberate kinin from T-kininogen and did not degrade T-kininogen. On the other hand, proteinase B with Mr of 30,400 showed a very weak activity for the liberation of kinin from T-kininogen and the cleavage of T-kininogen at pH 8.0. However, the enzyme extensively degraded T-kininogen at pH 4.5. Proteinase B also degraded HMW kininogen at pH 4.5 and pH 8.0, but liberated bradykinin only at pH 8.0. Thiol-proteinase inhibitory activities of HMW kininogen and T-kininogen were inactivated after the incubation with proteinase B at pH 4.5 but not at pH 8.0, while the correcting activity of HMW kininogen on the Fitzgerald trait plasma was inactivated at pH 4.5 and 8.0. The NH2-terminal amino acid sequences of proteinases A and B were different from each other, and distinguishable with those of serine proteinases in rat submaxillary gland so far reported. These results provide evidence that in addition to the known kallikrein, there exist at least two kinds of serine proteinases in rat submaxillary gland, both of which liberate bradykinin from rat HMW kininogen at pH 8.0 and modulate the functional activities of HMW kininogen and T-kininogen, degrading these proteins at pH 8.0 or 4.5.

Amino Acid Sequence↗

Identification of T-kininogen in high and low molecular weight kininogens deficient rat (brown Norway Katholiek strain).

Kinin release in Brown Norway Katholiek (B/N-Ka) rat plasma was compared with those of Brown Norway Kitasato and Sprague-Dawley rats by treating with rat plasma kallikrein, rat urinary kallikrein, snake venom kininogenase and trypsin. B/N-Ka rat plasma yielded no detectable amount of kinin by either plasma kallikrein, urinary kallikrein or snake venom kininogenase, but yielded variable amount of kinin by trypsin. The released kinin was proved to be isoleucylseryl-bradykinin by high performance liquid chromatography and bioassay profiles. B/N-Ka rat plasma formed a precipitation line against antiserum to T-kininogen, but no line against antiserum to HMW kininogen-light chain.

Animals↗

A new function of kininogens as thiol-proteinase inhibitors: inhibition of papain and cathepsins B, H and L by bovine, rat and human plasma kininogens.

The amidolytic activities of papain and rat liver cathepsins B, H and L were strongly inhibited by high (HMM) and low (LMM) molecular mass kininogens from bovine, human and rat plasmas, and their Ki values were estimated to be in the order of 10(-10) - 10(-11)M for papain and 10(-8) - 10(-9)M for cathepsins. The derivatives of bovine kininogens, HMM kinin-free protein, HMM kinin- and fragment 1 X 2-free protein, and LMM kinin-free protein also showed strong inhibitory activity toward these thiol-proteinases. These results suggest that a reactive site which interacts with thiol-proteinases is contained in the heavy chain portion in kininogens.

Animals↗

Demonstration of arginyl-bradykinin moiety in rat HMW kininogen: direct evidence for liberation of bradykinin by rat glandular kallikreins.

The amino acid sequence around kinin moiety in rat High-Molecular-Weight (HMW) kininogen was determined by isolating a peptide containing bradykinin after cyanogen bromide treatment of the purified kininogen as follows; NH2-Thr-Ser-Val-Ile-Arg-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-Ala-Pro-Arg- Val-Lys-Lys-. The data indicated that rat HMW kininogen contains the arginyl-bradykinin moiety, instead of lysyl-bradykinin. Kinins liberated from rat HMW kininogen by rat urinary and submaxillary kallikreins were identified to be bradykinin, not arginyl-bradykinin.

Amino Acid Sequence↗