Is High-Molecular-Weight-Renin Binding of Renin to the Protease Inhibitors and Lipoproteins?

1978 ◽  
Vol 55 (s4) ◽  
pp. 125s-128s
Author(s):  
K. Poulsen ◽  
A. H. Nielsen ◽  
S. Lykkegaard ◽  
C. Malling ◽  
J. Krøll ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Protease Inhibitors ◽  
Plasma Proteins ◽  
Tertiary Structure ◽  
Limited Proteolysis ◽  
Submaxillary Gland ◽  
Enzymic Activity ◽  
Molecular Weights ◽  
Α2 Macroglobulin

1. Two high-molecular-weight forms of renin (molecular weights 800 000 and 70 000) are present in mouse plasma. 2. The 800 000 form could be activated and converted into the fully active 40 000 form, by acid or limited proteolysis. The 70 000 form was activated without change in molecular weight. 3. In addition to its enzymic activity, renin was measured by a direct radioimmunoassay, which revealed that the current acid treatment of plasma did not activate all the renin present. 4. Renin is stored as fully active 40 000 renin, with a specific enzymic reactivity of 0·4 × 10−3 GU ng−1, in the submaxillary gland of mice. 5. Pure 125I-labelled 40 000 submaxillary renin did not bind to plasma proteins. However, by changing the tertiary structure of renin, it was bound to some of the plasma protease inhibitors; α2-macroglobulin, inter-α-trypsin inhibitor and α2-antithrombin. It was also bound to α1- and β1-lipoprotein, albumin and an unidentified plasma protein. No binding was seen to more than 50 other studied plasma proteins.

Renin Precursor Synthesis and Renin-Binding Proteins in the Mouse

1979 ◽  
Vol 57 (s5) ◽  
pp. 109s-110s ◽  
Author(s):  
K. Poulsen
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Protease Inhibitors ◽  
Plasma Proteins ◽  
Tertiary Structure ◽  
Submaxillary Gland ◽  
Α2 Macroglobulin ◽  
Precursor Synthesis ◽  
Predominant Form ◽  
Molecular Nature

1. The precursor synthesis of renin, the storage form in the kidney and the submaxillary gland, and the molecular nature of the forms in plasma were studied in the mouse. 2. Renin is synthesized as a precursor (pre-prorenin) with a molecular weight of 50 000. 3. Renin is stored in the submaxillary gland and the kidneys as fully active renin with a molecular weight of 40 000. 4. The predominant form of renin in plasma is the active mol. wt. 40 000 form. High-molecular-weight forms of renin (800 000 and 70 000) are also present in plasma. 5. Pure 125I-labelled mol. wt. 40 000 renin binds, after a change in the tertiary structure, to the plasma protease inhibitors α2-macroglobulin, inter-α-trypsin inhibitor and α2-antithrombin. It binds also to lipoprotein and an unidentified plasma protein. No binding was seen to more than 50 other studied plasma proteins. 6. The high-molecular-weight forms of renin in plasma may be complexes of renin with plasma protease inhibitors and lipoprotein.

The Kinetics Of The Inhibition Of Human Plasma Kallikrein By Plasma Protease Inhibitors: Role Of High Molecular Weight Kininogen

1981 ◽  
Author(s):  
M Schapira ◽  
A James ◽  
C F Scott ◽  
F Kueppers ◽  
H L James ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Protease Inhibitors ◽  
Substrate Inhibition ◽  
Catalytic Efficiency ◽  
Reaction Rates ◽  
Plasma Kallikrein ◽  
High Molecular Weight Kininogen ◽  
Α2 Macroglobulin ◽  
Competitive Inhibitors

Plasma kallikrein (KAL) is inhibited by several plasma protease inhibitors, including C1-inhibitor (C1-INH), antithrombin III (ATIII), α1-antitrypsin (α1AT), and α2-macroglobulin (α2M). To assess the mechanism of action and the relative importance of these inhibitors, we have undertaken inhibition studies with purified proteins, using H-D-Pro- Phe-Arg-Nan as KAL substrate. Inhibition was competitive with C1INH, ATIII, and α1AT and noncompetitive with α2M. KAL retained 14% of its catalytic efficiency when complexed to α2M. The rate constants for inhibition by C1INH, ATIII, α1AT, and α2M were 28, 0.18, 0.003, and 6.9 M-ls-1(10-3) respectively. Michaelis-Menten kinetics was observed for the inhibition by ATIII, αlAT, and α2M. The constants for the rate-limiting formation of the irreversible complexes were 16, 0.27 and 2.0 s-1(xl02), while the KI’s for the reversible complex were 86, 63, and 0.29 γM, respectively for ATIII, α1AT and α2M. In_contrast, no Michaelis-Menten complex was observed when C1INH inhibited KAL. These results indicate that (a) C1INH is the most efficient inhibitor of KAL, (b) α2M is a significant inhibitor of KAL, (c) both ATIII and αlAT are probably not significant inhibitors of KAL. We have shown that high molecular weight kininogen (HMWK) decreases the inactivation rate of KAL by C1INH by forming a reversible complex with KAL. We now report that the reaction rates of KAL with ATIII and α1AT, which are competitive inhibitors, were decreased by 50%, when HMWK was 1 U/ml or 0.73 γM. When KAL was inhibited by α2M, a noncompetitive inhibitor, the inactivation rates were identical in the presence or absence of HMWK. Since HMWK protects KAL from being inhibited by competitive inhibitors but not by a noncompetitive one, these results confirm our previous observation indicating that the binding site for IMWK on KAL is closely linked to its catalytic site.

Abstract P161: Conversion of Secreted High-Molecular-Weight FGF-2 to an 18 kDa Low-Molecular-Weight FGF-2 by Limited Proteolysis Suppresses the Paracrine Induction of Cardiomyocyte Hypertrophy

2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Jon-Jon R Santiago ◽  
Brian P Bestvater ◽  
Robert R Fandrich ◽  
Elissavet Kardami
Keyword(s):  
Molecular Weight ◽  
Serine Protease ◽  
High Molecular Weight ◽  
Protease Inhibitors ◽  
Biological Activities ◽  
Limited Proteolysis ◽  
Specific Inhibitor ◽  
Conditioned Media ◽  
Cardiomyocyte Hypertrophy ◽  
Low Molecular Weight

Background: High molecular weight, 23 kDa rat FGF-2 (Hi-FGF-2) is composed of an N-terminal extension as well as the 18 kDa core sequence present in low molecular weight (Lo-) FGF-2. Hi- and Lo-FGF-2 have distinct biological activities: unlike Lo-FGF-2, Hi-FGF-2, which is secreted by cardiac non-myocytes, promotes cardiomyocytes hypertrophy in vivo and in vitro . We tested if the paracrine pro-hypertrophic effects of secreted Hi-FGF-2 can be blunted by limited proteolysis of its N-terminal extension. Experimental: Heparin-sepharose-bound Hi-FGF-2 present in rat tissue extracts converted to an approximately 18 kDa protein (*Lo-FGF-2) through truncation of its N-terminal extension, in the absence of protease inhibitors. Serine protease inhibitors such as PMSF fully prevented this conversion. Similarly, purified recombinant rat Hi-FGF-2 was converted to *Lo-FGF-2 by thrombin, a serine protease, and the effect was prevented by hirudin, a thrombin specific inhibitor. Conditioned media from unstimulated or angiotensin II-stimulated rat cardiac non-myocytes (fibroblasts) were used to treat neonatal cardiomyocytes in culture, in the absence or presence of thrombin. Conditioned medium from stimulated (but not unstimulated) cells contained Hi-FGF-2, which promoted cardiomyocyte hypertrophy (increase in cell surface area), and the effect was due to secreted FGF-2 because it was prevented by neutralizing anti-FGF-2 antibodies. Thrombin itself had no effect on cell size but prevented the pro-hypertrophic effect of the conditioned media; while converting the secreted Hi-FGF-2 to *Lo-FGF-2. Conclusions: The truncation of the N-terminal extension of secreted Hi-FGF-2 by serine protease(s) can provide a strategy to prevent undesirable paracrine effects of Hi-FGF-2 (such as cardiac hypertrophy), while maintaining potentially beneficial (cytoprotective, angiogenic) effects associated with Lo-FGF-2.

Protofilament as a structural element of flagella of haloalkalophilic archaebacteria

1994 ◽  
Vol 40 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Oleg V. Fedorov ◽  
Michael G. Pyatibratov ◽  
Alla S. Kostyukova ◽  
Natalja K. Osina ◽  
Valery Yu. Tarasov
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Limited Proteolysis ◽  
Proteolytic Cleavage ◽  
Complete Disappearance ◽  
Structural Element ◽  
Molecular Weights ◽  
Nacl Concentration

Flagella of the haloalkalophilic archaebacterium Natronobacterium magadii were purified and characterized. The diameter of the flagella was 10 nm. It was shown that the flagella consist of four major proteins with molecular weights of 105 000, 60 000, 59 000, and 45 000. With decreasing NaCl concentration, the flagella dissociated into protofilaments. The structure of dissociated flagella and individual flagellins was studied by limited proteolysis. It was found that proteolytic cleavage of flagellins in dissociated flagella into high molecular weight fragments (about 40 000) did not lead to protofilament degradation. It was shown that the most stable fragment is formed from the 60 000 molecular weight flagellin. Cleavage of this fragment led to complete disappearance of protofilaments. On the basis of the data obtained, possible principles of archaebacterial flagellar construction are discussed.Key words: flagellin, archaebacteria, protofilaments, Natronobacterium magadii.

scholarly journals Multiple forms of nuclear deoxyribonucleic acid polymerases and their relationship with the soluble enzyme

1973 ◽  
Vol 131 (2) ◽  
pp. 237-246 ◽  
Author(s):  
R. L. P. Adams ◽  
M. A. L. Henderson ◽  
W. Wood ◽  
J. G. Lindsay
Keyword(s):  
Molecular Weight ◽  
Dna Synthesis ◽  
High Molecular Weight ◽  
Dna Polymerase ◽  
Deae Cellulose ◽  
Polymerase Activity ◽  
Enzymic Activity ◽  
Supernatant Fraction ◽  
Molecular Weights ◽  
Molecular Weight Peak

1. DNA polymerase from nuclear and supernatant fractions of cultured mouse L929 cells was fractionated on columns of Sephadex G-200, Sepharose 4B and of DEAE-cellulose. Several peaks of activity are found on Sephadex chromatography and the distribution of activity between these depends on: (a) the source of the enzyme, i.e. nuclear or supernatant fraction; (b) the mode of extraction of the enzyme from the nucleus; (c) the amount of enzyme applied to the column. 2. The DNA polymerase activity in the lower-molecular-weight peaks (approximate molecular weights are 35000, 70000 and 140000) is firmly bound within the cell nucleus and shows a preference for native DNA as template, whereas the high-molecular-weight peak (peak I, molecular weight 250000 or greater) is found in supernatant fractions and shows greater activity with a denatured DNA template. 3. During periods of DNA synthesis the high-molecular-weight enzyme becomes more firmly bound within the nucleus. 4. Peak I enzymic activity is relatively unstable and is inhibited by thiol-blocking reagents and deoxycholate, but it is stimulated by univalent cations. 5. Very little endonuclease is present in the polymerase preparations, but a very active exonuclease and nucleoside diphosphokinase are present. On Sephadex chromatography, however, it was shown that the immediate precursors for DNA synthesis, at least by peak I enzyme, are the deoxyribonucleoside triphosphates. 6. Attempts to decrease the molecular weight of the peak I enzyme while still retaining activity failed.

Soluble Fibrin Complexes and Fibrinogen Heterogeneity in Diabetes mellitus

1980 ◽  
Vol 44 (03) ◽  
pp. 130-134 ◽  
Author(s):  
E B Tsianos ◽  
N E Stathakis
Keyword(s):  
Diabetes Mellitus ◽  
Molecular Weight ◽  
Plasma Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Lower Molecular Weight ◽  
Polyacrylamide Gels ◽  
Soluble Fibrin ◽  
Α2 Macroglobulin ◽  
Patients With Diabetes

SummaryThe presence of soluble fibrin complexes (SFC) measured by gel filtration of plasma on 4% agarose columns, fibrinogen heterogeneity on 3.5% SDS-polyacrylamide gels and the concentrations of several plasma proteins were evaluated in 39 patients with diabetes mellitus (DM) and 19 matched control subjects. A small but significant increase of SFC was found in DM (p<0.01). On individual basis 51.2% of the patients had increased SFC (>M + 2 SD of the controls). Polyacrylamide gel electrophoresis of the SFC showed no evidence of cross-linking or proteolysis. Plasma clots formed in the presence of EDTA and trasylol were analysed in SDS-polyacrylamide gels in a normal and two lower molecular weight fibrin bands (band I, II, III). The percentage of band I fibrinogen was in diabetics (65.3 ± 4.7%) lower than that of the controls (71.8 ± 4.5%) (p < 0.01). Fibrinogen levels, antithrombin III, α1-antitrypsin, α2-macroglobulin and plasminogen were significantly increased in DM. We suggest that in DM there is an enhancement of intravascular fibrin formation and accelerated fibrinogen degradation to lower molecular weight forms.

The Contact Phase of Blood Coagulation in Diabetes Mellitus and in Patients with Vasculopathy

1984 ◽  
Vol 52 (03) ◽  
pp. 221-223 ◽  
Author(s):  
M Christe ◽  
P Gattlen ◽  
J Fritschi ◽  
B Lämmle ◽  
W Berger ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Molecular Weight ◽  
Blood Coagulation ◽  
High Molecular Weight ◽  
Negative Correlation ◽  
Factor Xii ◽  
C1 Inhibitor ◽  
High Molecular Weight Kininogen ◽  
Contact Phase ◽  
Α2 Macroglobulin

SummaryThe contact phase has been studied in diabetics and patients with macroangiopathy. Factor XII and high molecular weight kininogen (HMWK) are normal. C1-inhibitor and also α2-macroglobulin are significantly elevated in diabetics with complications, for α1-macroglobulin especially in patients with nephropathy, 137.5% ± 36.0 (p <0.001). C1-inhibitor is also increased in vasculopathy without diabetes 113.2 ± 22.1 (p <0.01).Prekallikrein (PK) is increased in all patients’ groups (Table 2) as compared to normals. PK is particularly high (134% ± 32) in 5 diabetics without macroangiopathy but with sensomotor neuropathy. This difference is remarkable because of the older age of diabetics and the negative correlation of PK with age in normals.

Homocysteinylation score of high-molecular weight plasma proteins

Amino Acids ◽  
2013 ◽  
Vol 46 (4) ◽  
pp. 893-899 ◽  
Author(s):  
Alexandr A. Zhloba ◽  
Tatiana F. Subbotina
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Plasma Proteins

Gene Expression of the High Molecular Weight Proteinase Inhibitor α2-Macroglobulin

1992 ◽  
Vol 373 (2) ◽  
pp. 509-516 ◽  
Author(s):  
EVA KRAUSE ◽  
URSULA WEGENKA ◽  
GARSTEN MÖLLER ◽  
FRIEDEMANN HORN ◽  
PETER C. HEINRICH
Keyword(s):  
Gene Expression ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
Proteinase Inhibitor ◽  
Α2 Macroglobulin

Relation between Molecular Weights and Physical Properties of Rubber Fractions

1941 ◽  
Vol 14 (3) ◽  
pp. 580-589 ◽  
Author(s):  
G. Gee ◽  
L. R. G. Treloar
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Physical Properties ◽  
High Molecular Weight ◽  
Elastic Properties ◽  
Elastic Material ◽  
Experimental Results ◽  
Molecular Weights ◽  
High Elasticity ◽  
Latex Rubber

Abstract As high elasticity is a property possessed only by substances of high molecular weight, it is of interest to enquire into the relation between the elastic properties of a highly elastic material such as rubber and its molecular weight. An investigation on these lines has been made possible through the work of Bloomfield and Farmer, who have succeeded in separating natural rubber into fractions having different average molecular weights. The more important physical properties of these fractions have been examined with the object of determining which of the properties are dependent on molecular weight and which are not. Fairly extensive observations were made on the fractions from latex rubber referred to as Nos. 2, 3 and 4 by Bloomfield and Farmer, and some less extensive observations were carried out on the less oxygenated portion of fraction No. 1 obtained from crepe rubber (called hereafter 1b) . Before considering these experimental results, and their relation to the molecular weights of the fractions, it will be necessary to refer briefly to the methods used for the molecular-weight determinations, and to discuss the significance of the figures obtained.

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