scholarly journals Studies on proteolytic activity in commercial myoglobin preparations

1971 ◽  
Vol 125 (3) ◽  
pp. 865-868 ◽  
Author(s):  
D. F. Goldspink ◽  
D. Holmes ◽  
R. J. Pennington
Keyword(s):  
Skeletal Muscle ◽  
Proteolytic Activity ◽  
Enzyme Preparation ◽  
Soluble Fraction ◽  
Maximum Activity ◽  
Soya Bean ◽  
Exclusion Limit ◽  
Bean Trypsin Inhibitor ◽  
Myofibril Preparation ◽  
Nitrophenyl Ester

Commercial myoglobin preparations from horse skeletal muscle degraded casein. The maximum activity was at pH8–8.5. A muscle myofibril preparation was also attacked. The protease could be partly separated from the myoglobin by selective ultrafiltration through a membrane with an exclusion limit of mol.wt. 30000. A greater than 1000-fold purification of the proteolytic activity was achieved by affinity chromatography with soya-bean trypsin inhibitor bound to CM-cellulose. The enzyme preparation hydrolysed p-toluenesulphonyl-l-arginine methyl ester and N-benzyloxycarbonyl-l-tyrosine p-nitrophenyl ester. Its activity was inhibited strongly by soya-bean and ovomucoid trypsin inhibitors, serum and the soluble fraction of muscle homogenates. EDTA, p-chloromercuribenzoate and phenylmethylsulphonyl fluoride also caused some inhibition.

Cold Promoted Activation of Factor VII VI. Effect of Inhibitors

1973 ◽  
Vol 29 (03) ◽  
pp. 633-643
Author(s):  
H Gjønnæss
Keyword(s):  
Soya Bean ◽  
Factor Vii ◽  
Plasma Kallikrein ◽  
Contact Activation ◽  
Activation Reaction ◽  
Hexadimethrine Bromide ◽  
Bean Trypsin Inhibitor ◽  
Plasma Arginine ◽  
Kallikrein Activity ◽  
Effect Of Inhibitors

SummaryThe cold promoted activation of factor VII occurs in parallel with an activation of a plasma arginine esterase, and, on inhibition of the cold activation of factor VII, the esterase activation also decreased. The inhibitor pattern supported our theory that the arginine esterase that is activated in the cold activation of factor VII is plasma kallikrein.The cold activation of factor VII was completely inhibited with soya bean trypsin inhibitor in doses that did not interfere with the contact activation. On the other hand, inhibition of the contact activation with hexadimethrine bromide did not interfere with the cold activation of factor VII except when this was kaolin induced. Contact and cold activation therefore appear to represent two different pathways for the activation of factor VII. The cold activation reaction is probably mediated by the activation of plasma prekallikrein, and inhibition of the plasma kallikrein activity correlates with the inhibition of the cold promoted activation of factor VII.

Activation of latent collagenase from polymorphonuclear leukocytes by cathepsin G

1979 ◽  
Vol 44 (10) ◽  
pp. 3177-3182 ◽  
Author(s):  
Mária Stančíková ◽  
Karel Trnavský
Keyword(s):  
Affinity Chromatography ◽  
Trypsin Inhibitor ◽  
Polymorphonuclear Leukocytes ◽  
Soya Bean ◽  
Cathepsin G ◽  
Sepharose Column ◽  
Bean Trypsin Inhibitor ◽  
Human Polymorphonuclear Leukocytes

Cathepsin G was isolated from human polymorphonuclear leukocytes and purified by affinity chromatography on Antilysin-Sepharose column. Purified enzyme activated later collagenase isolated from leukocytes. Activation at 36°C was maximal after 30 min incubation. Inhibitors of cathepsin G - soya-bean trypsin inhibitor, diisopropyl phosphofluoridate and Antilysin were active in inhibiting the activation of latent collagenase by cathepsin G.

CHOLINE KINASE OF RAPESEED (BRASSIGA CAMPESTRIS L.)

1957 ◽  
Vol 35 (1) ◽  
pp. 853-863
Author(s):  
T. Ramasarma ◽  
L. R. Wetter
Keyword(s):  
Calcium Phosphate ◽  
Enzyme Preparation ◽  
Brassica Campestris ◽  
Maximum Activity ◽  
Choline Kinase ◽  
Aqueous Extracts ◽  
Neutral Ph ◽  
Sulphydryl Groups

Choline kinase from aqueous extracts of Polish rapeseed (Brassica campestris L.) has been purified 25-fold by fractionation with acetone and calcium phosphate gel. The purified enzyme was relatively stable when stored frozen at neutral pH, and was active over a broad range of pH, the optimum being at about pH 8.6 – 10.0. The enzyme required Mg++ and exhibited maximum activity only when the Mg++: ATP ratio was 1:1. Phosphorylcholine, ADP, and Mn++ inhibited the activity. In addition to choline, the enzyme preparation phosphorylated dimethyl- and diethyl-aminoethanol but not ethanolamine. The choline kinase from rapeseed is similar to that from yeast except that the former does not require sulphydryl groups for activation.

Proteolytic Activity of Skeletal Muscle of Normal and Dystrophic Chickens and Rabbits

1966 ◽  
Vol 6 (4) ◽  
pp. 269-278 ◽  
Author(s):  
A.A. Iodice ◽  
V. Leong ◽  
I.M. Weinstock
Keyword(s):  
Skeletal Muscle ◽  
Proteolytic Activity

STUDIES ON CORTICOSTERONE C-20 REDUCTION IN THE MOUSE

1962 ◽  
Vol 40 (1) ◽  
pp. 1797-1810 ◽  
Author(s):  
R. E. Krehbiel ◽  
A. F. Burton ◽  
Marvin Darrach
Keyword(s):  
Intravenous Injection ◽  
Mouse Liver ◽  
Enzyme Preparation ◽  
Soluble Fraction ◽  
Reductase Activity ◽  
Kinetics Of

The intravenous injection of corticosterone in the mouse was followed by liver assays for corticosterone and 20α- and 20β-dihydrocorticosterone. The 20α-epimer proved to be the more abundant product. Corticosterone 20α-reductase activity of mouse liver was shown to be associated with the dialyzed soluble fraction of the cell which served as an enzyme preparation for a study of certain properties of corticosterone 20α-reductase and the kinetics of the forward and reverse reactions.

scholarly journals Purification and characterization of a multicatalytic high-molecular-mass proteinase from rat skeletal muscle

1985 ◽  
Vol 228 (1) ◽  
pp. 161-170 ◽  
Author(s):  
B Dahlmann ◽  
L Kuehn ◽  
M Rutschmann ◽  
H Reinauer
Keyword(s):  
Skeletal Muscle ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Hydrolytic Activity ◽  
Maximum Activity ◽  
Disc Electrophoresis ◽  
Polyacrylamide Gels ◽  
Rat Skeletal Muscle ◽  
Muscle Extract

A proteolytic enzyme was purified from the post-myofibrillar fraction of rat skeletal muscle. The purification procedure consisted of fractionation of the muscle extract by (NH4)2SO4, chromatography on DEAE-Sephacel, fast protein liquid chromatography on Mono Q and gel filtration on Sepharose 6B. The enzyme preparation appeared to be homogeneous as judged by disc electrophoresis in polyacrylamide gels and by immunoelectrophoresis. The isoelectric point of the proteinase is at 5.1-5.2. The enzyme has an Mr of about 650 000 and dissociates into eight subunits of Mr 25 000-32 000 when subjected to electrophoresis in sodium dodecyl sulphate/polyacrylamide gels. The proteinase contains hydrolytic activity against N-blocked tripeptide 4-methyl-7-coumarylamide substrates with an arginine or phenylalanine residue adjacent to the leaving group. Maximum activity with the first group of substrates was at pH 10.5, and this activity was inhibited by leupeptin, chymostatin and Ca2+. Maximum activity with the latter group of substrates was at pH 7.5, and was also inhibited by the two microbial inhibitors, but was activated by Ca2+ ions. By using [14C]methylcasein as a substrate, maximum activity was observed at pH9.0, and this proteolytic activity was not affected by leupeptin, was enhanced by chymostatin and inhibited by Ca2+. Similar effects were observed when benzyloxycarbonyl-Leu-Leu-Glu 2-naphthylamide was used as a substrate. These enzymic activities were abolished by p-hydroxymercuribenzenesulphonic acid or mersalyl acid, whereas a small activation was observed with cysteine or dithiothreitol.

scholarly journals Surface-simulation synthesis of the substrate-binding site of an enzyme. Demonstration with trypsin

1985 ◽  
Vol 226 (2) ◽  
pp. 477-485 ◽  
Author(s):  
M Z Atassi
Keyword(s):  
Binding Site ◽  
Trypsin Inhibitor ◽  
Binding Activity ◽  
Enzymic Activity ◽  
Soya Bean ◽  
Free Form ◽  
Protein Substrates ◽  
Substrate Analogues ◽  
Bean Trypsin Inhibitor ◽  
Alpha 1 Antitrypsin

From the X-ray co-ordinates of bovine trypsin and its complexes with substrate analogues (benzamidine) and with soya-bean trypsin inhibitor, a peptide (TP) was designed and synthesized by surface-simulation synthesis, a concept previously introduced by this laboratory, to mimic the binding site of trypsin. Also, a control peptide (CTP) was synthesized that contained all the amino acids present in the TP peptide, except that their order was randomized. The radioiodinated TP peptide bound specifically to adsorbents of benzamidine, whereas the control CTP peptide exhibited no binding activity. Conjugates to succinyl (3-carboxypropionyl)-lysozyme of the TP peptide, control CTP peptide and other unrelated peptides were examined by a radiometric binding assay for the ability to bind soya-bean trypsin inhibitor and human alpha 1-antitrypsin. Conjugates of the TP peptide exhibited considerable binding activity to adsorbents of soya-bean trypsin inhibitor or alpha 1-antitrypsin. None of the other peptide conjugates possessed any binding activity. Action of the active-site-directed reagents phenylmethanesulphonyl fluoride and di-isopropyl phosphorofluoridate on free TP and CTP peptides resulted in the modification of a serine residue in the TP peptide whereas the CTP peptide remained unaltered. The TP peptide, either in the free form or as a conjugate on succinyl-lysozyme, had no enzymic activity on protein substrates or on tosylarginine methyl ester. These findings indicated that the binding activity of an enzyme was well mimicked by the surface-stimulation peptide but that reproduction of the catalytic activity was not obtained.

scholarly journals Tocopherols, Polyprenols and Steroids from Passiflora edulis and Bioactivities of its Extractives

2017 ◽  
Vol 16 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Md Abdul Aziz ◽  
Monira Ahsan ◽  
Choudhury Mahmood Hasan ◽  
Mohammad Mehedi Masud
Keyword(s):  
Methanolic Extract ◽  
Soluble Fraction ◽  
Radical Scavenging ◽  
Antimicrobial Activities ◽  
Maximum Activity ◽  
Free Radical Scavenging ◽  
Clot Lysis ◽  
Passiflora Edulis ◽  
Ic50 Value ◽  
Free Radical Scavenging Assay

?-tocopherol (1), ?-tocopherol (2), polyprenol-12 (3), polyprenol-15 (4), stigmasterol and ?-sitosterol were isolated from the yellow flavicarpa variety of leaves of Passiflora edulis. The structures of the isolated compounds were elucidated using 1H-NR and 13C-NMR spectral analysis. The organic and aqueous soluble fractions of crude methanolic extract were evaluated for the antioxidant, cytotoxic, thrombolytic and antimicrobial activities. In DPPH free radical scavenging assay, the aqueous soluble fraction displayed maximum activity having IC50 value of 139.56?g/ml. On the other hand, dichloromethane soluble fraction revealed maximum cytotoxic (LC50 24.17?g/ml) and thrombolytic (14.49% clot lysis) activities, when compared to the respective blanks.Dhaka Univ. J. Pharm. Sci. 16(1): 55-60, 2017 (June)

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