scholarly journals SECRETION OF PLASMINOGEN ACTIVATOR BY STIMULATED MACROPHAGES

1974 ◽  
Vol 139 (4) ◽  
pp. 834-850 ◽  
Author(s):  
Jay C. Unkeless ◽  
Saimon Gordon ◽  
E. Reich
Keyword(s):  
Amino Acids ◽  
Catalytic Activity ◽  
Plasminogen Activator ◽  
Electrophoretic Mobility ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Plasminogen Activators ◽  
Peritoneal Macrophages ◽  
Chemical Labeling ◽  
Specific Catalytic Activity

Cultured thioglycollate-stimulated peritoneal macrophages synthesize, accumulate, and continuously release high levels of plasminogen activators for at least 4 days whereas cultures of unstimulated macrophages do not; the higher specific catalytic activity of released vs. cell-associated enzyme suggests that the plasminogen activators are actively secreted. The major macrophage plasminogen activator is a serine protease of mol wt 48,000, and thus resembles the comparable enzyme released by virally transformed fibroblasts. Macrophages release a second plasminogen activator of mol wt 28,000 that is also a serine enzyme. The secretion products released by stimulated and unstimulated macrophages have been compared by SDS-polyacrylamide gel electrophoresis after chemical labeling with 3H-DFP or biosynthetic labeling with 14C-amino acids. These procedures show that some proteins are formed in both cultures, whereas others are uniquely secreted by each type of macrophage. The serine enzymes released by the two kinds of macrophages differ in specificity and electrophoretic mobility.

Polyacrylamide Gel Electrophoresis without a Stacking Gel: Use of Amino Acids as Electrolytes

2001 ◽  
Vol 291 (2) ◽  
pp. 300-303 ◽  
Author(s):  
Taeho Ahn ◽  
Sung-Kun Yim ◽  
Ho-Il Choi ◽  
Chul-Ho Yun
Keyword(s):  
Amino Acids ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel

scholarly journals Studies on Platelet Glycoproteins by Surface Labeling and SDS Polyacrylamide Gel Electrophoresis

1977 ◽  
Author(s):  
I. Hagen ◽  
N.O. Solum ◽  
M. Peterka
Keyword(s):  
Electrophoretic Mobility ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Conformational State ◽  
Polyacrylamide Gel ◽  
The Other ◽  
Metabolic Inhibitors ◽  
Conventional System ◽  
Platelet Surface ◽  
Release Reaction

Platelet surface (glyco)proteins, and alterations in these in connection with the thrombin-induced release reaction has been studied. Platelets were labeled by lactoperoxidase-catalyzed iodination, and examined by SDS gel electrophoresis in two different gel systems, one conventional(J. Biol. Chem.1969 244 4406), and the other containing urea and EDTA in the gels. In the conventional system the bulk of radioactivity coincided with a PAS band (GP III) of MW about 100, 000. In the other system, the main radioactive peak appeared in the GP II area (MW 120,000), and a shift in the PAS stain intensity from GP III to GP II was seen. Thrombasthenic platelets showed only traces of the GP II band in both systems. The bulk of radioactivity was associated with the surface glycopolypeptide GPS, which is present, but not labeled in normal platelets. In thrombin-released platelets, GPS in its unreduced state has an altered electrophoretic mobility compared to control platelets and platelets which have been incubated with metabolic inhibitors to prevent secretion. The findings indicate that the GP III band consists of two different polypeptides, one of which appears in the GP II area in gels containing urea and EDTA. Further, that thrombasthenic platelet membrane exists in a conformational state different from that of normal platelets. And finally, GPS is in some way involved in, or influenced by, the thrombin-induced release reaction.

scholarly journals An Effective Method of Isolating Honey Proteins

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2399 ◽  
Author(s):  
Aleksandra Bocian ◽  
Justyna Buczkowicz ◽  
Marcin Jaromin ◽  
Konrad Kamil Hus ◽  
Jaroslav Legáth
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Gel Electrophoresis ◽  
Free Amino ◽  
Polyacrylamide Gel Electrophoresis ◽  
Pollen Grains ◽  
Distilled Water ◽  
Protein Isolation ◽  
Saturated Phenol

Honey is a natural sweetener composed mostly of sugars, but it contains also pollen grains, proteins, free amino acids, and minerals. The amounts and proportions of these components depend on the honey type and bee species. Despite the low content of honey protein, they are becoming a popular study object, and have recently been used as markers of the authenticity and quality of honey. Currently, the most popular methods of protein isolation from honey are dialysis against distilled water, lyophilization of dialysate, or various precipitation protocols. In this work, we propose a new method based on saturated phenol. We tested it on three popular polish honey types and we proved its compatibility with both 1D and 2D polyacrylamide gel electrophoresis (PAGE) and MS (mass spectrometry) techniques. The elaborated technique is also potentially less expensive and less time-consuming than other previously described methods, while being equally effective.

Comparison of subunits of cardiac, brain, and kidney Na+-K+-ATPase

1985 ◽  
Vol 248 (3) ◽  
pp. C247-C251 ◽  
Author(s):  
A. McDonough ◽  
C. Schmitt
Keyword(s):  
Electrophoretic Mobility ◽  
Gel Electrophoresis ◽  
Cardiac Tissue ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Beta Subunit ◽  
Binding Affinities ◽  
Ouabain Binding ◽  
Heart Membranes ◽  
Atpase Subunits

Na+-K+-ATPase is in low abundance in cardiac tissue. Therefore, we utilized antibodies to detect the cardiac Na+-K+-ATPase subunits and to compare their characteristics with those of kidney and brain Na+-K+-ATPase subunits. By using crude preparations of heart membranes as well as purified sarcolemmal membranes from guinea pig hearts, we resolved peptides by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, blotted them onto diazotized paper, and detected Na+-K+-ATPase subunits with antibodies generated against highly purified kidney Na+-K+-ATPase holoenzyme. We tested the hypothesis that the two families of ouabain-binding affinities described in heart are due to two forms of alpha-subunit, analogous to the two forms with different affinities for ouabain described in brain. Although the antibodies did detect two forms of catalytic subunit in brain (alpha and alpha +), only one form of alpha was detected in the heart membranes, with the same electrophoretic mobility as kidney alpha. Cardiac beta-subunit could also be detected with the antikidney antibodies. It had a similar electrophoretic mobility to that described for kidney beta, whereas brain beta had a higher mobility.

scholarly journals The Nα-acetylenkephalin carboxypeptidase activity of N-acetyltyrosine deacetylase from monkey kidney. Purification, characterization and substrate specificity

1983 ◽  
Vol 209 (2) ◽  
pp. 471-479 ◽  
Author(s):  
S T George ◽  
A S Balasubramanian
Keyword(s):  
Amino Acids ◽  
Gel Electrophoresis ◽  
High Speed ◽  
Metal Chelate ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Protein Band ◽  
Monkey Kidney ◽  
Hydrophobic Amino Acids

N alpha-Acetylenkephalin carboxypeptidase was co-purified with N-acetyltyrosine deacetylase from monkey kidney. Almost 90% of the activity from the homogenate was recovered in a high-speed supernatant without the use of detergents. The crucial steps in the purification were Cibacron Blue F3GA-Sepharose chromatography (involving negative and positive binding sequentially) and metal chelate affinity chromatography. The purified enzyme showed three bands on gel electrophoresis under non-denaturing conditions. All the three bands exhibited both N-acetyltyrosine deacetylase and N-acetylenkephalin carboxypeptidase activity, indicating their co-migration, Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis in the presence and absence of 2-mercaptoethanol gave a single protein band of mol.wt. 34 000. The native enzyme was a dimer of mol.wt. 66 000 as observed on Bio-Gel P-300 gel filtration. The carboxypeptidase removed two amino acids from the C-terminal end of either N-acetyl[Met5]- or N-acetyl[Leu5]-enkephalin. Non-acetylated enkephalins were less active as substrates. Peptides with their carboxy end blocked were inactive as substrates. Models suggested for carboxypeptidase A [Hartsuck & Lipscomb (1971) Enzymes 3, 1-56] support the idea that the kidney N-acetylated aromatic amino acid deacetylase or acylase III [Endo (1978) Biochim. Biophys. Acta 523, 207-217] can act as a carboxypeptidase on peptides having hydrophobic amino acids at the C-terminal end.

scholarly journals The inhibition by diphenyleneiodonium and its analogues of superoxide generation by macrophages

1987 ◽  
Vol 242 (1) ◽  
pp. 103-107 ◽  
Author(s):  
J T Hancock ◽  
O T Jones
Keyword(s):  
Cytochrome B ◽  
Gel Electrophoresis ◽  
Respiratory Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Peritoneal Macrophages ◽  
Superoxide Generation ◽  
Radical Generation ◽  
Selective Prevention ◽  
Mitochondrial Respiratory Activity

Peritoneal macrophages were elicited in rats by using casein as a stimulus; when stimulated with phorbol 12-myristate 13-acetate (PMA) they produced O2.-. Nearly 60% of the total cytochrome b had a low Em,7.0 of -247 mV, typical of the cytochrome b component found in the NADPH-dependent O2(.-)-generating oxidase of neutrophils. The rate of O2.- generation by macrophages was 1.23 mol of O2.-/s per mol of cytochrome b. Treatment of intact macrophages with diphenyleniodonium (DPI) at 0.9 microM caused 50% inhibition of PMA-induced O2.- generation, with little effect on mitochondrial respiratory activity; KCN inhibited respiratory activity without affecting PMA-induced O2.- generation. A similar specificity of inhibition was found for di-2-thienyliodonium (50% inhibition of O2.- generation at 0.5 microM) and, at higher concentrations, for diphenyl iodonium. When macrophage suspensions were incubated with [125I]DPI followed by autoradiography of SDS/polyacrylamide-gel-electrophoresis-separated polypeptides, radioactivity was most strongly associated with a band of Mr 45,000, similar to that found in neutrophils [Cross & Jones (1986) Biochem. J. 237, 111-116]. The O2(.-)-generating oxidase of macrophages appears to have components in common with the NADPH oxidase of neutrophils, despite differences in activity. Its sensitivity to DPI suggests that selective prevention of radical generation by macrophages in vivo is possible.

scholarly journals Biology of amazonian mosquitoes. III. Esterase isozymes in Anopheles darlingi.

1985 ◽  
Vol 15 (1-2) ◽  
pp. 167-178 ◽  
Author(s):  
Joselita M.M. dos Santos ◽  
Eucleia P.B. Contel ◽  
Warwick E. Kerr
Keyword(s):  
Electrophoretic Mobility ◽  
Gel Electrophoresis ◽  
Developmental Stages ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Anopheles Darlingi ◽  
Genetic Studies ◽  
Esterase Isozymes ◽  
Phenotypic Distribution ◽  
Polymorphic System

Six esterase isozymes were studied during the development of Anopheles darlingi by using polyacrylamide gel electrophoresis and two different substrates, a-naphthylcelate and a-naphthylpropionate. Esterases 5 and 6'were detected in all developmental stages esterases 1 and 2 were more intensively stained if larvae, while esterases 3 and 4 were better visualized in pupae and adults. Strong differences in intensity of some of the isozymes were observed during the pupal stage.Four out of the six isozymes showed variation in the electrophoretic mobility. Esterase-2 was choosed for genetic studies, because was the best stained isozyme in the gels. Two codominant alleles {Est2*S and Est2*F) code for this polymorphic system, with the Est*S frequency equal to 0.521. Phenotypic distribution is in agreement with hardy-Weinberg expectations.

Purification Of 1- And 0-Gla Prothrombins And Their Differentiation With Normal And Other Dicoumarol-Induced Prothrombins

1981 ◽  
Author(s):  
O P Malhotra
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Electrophoretic Mobility ◽  
Vitamin K ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
The Other ◽  
Multiple Forms ◽  
Isoelectric Precipitation ◽  
Antigenic Activity

In normal prothrombin, 10-glutamyl residues present in the amino portion of the molecule are carboxylated to form γ-carboxyglutamic acids (gla). Dicoumarol, an antagonist of vitamin K, induces the production of (partially) acarboxylated atypical prothrombins. In addition to our atypical varieties, viz. 7−,5− and 2-gla prothrombins, we have isolated two more atypical molecules, one containing 1.0±0.1 gla (1-gla prothrombin) and the other approximately 0.25 gla (0-gla prothrombin). These two variants adsorbed onto alumina Cγ-gel (Bio-Rad), similar to 2-gla protein, but were derived from 40 to 50% (NH4)2SO4 saturation. The purified materials, obtained after isoelectric precipitation followed by preparatory polyacrylamide-gel electrophoresis and heparin agarose chromatography, showed a single component by analytical disc-gel electrophoresis both in the presence or absence of sodium dodecyl sulfate (SDS) and contained antigenic activity comparable to that of normal prothrombins.The pI’s of the two variants by column electrofocusing were each 4.835±0.015. Similarly, the two proteins did not reveal any difference in electrophoretic mobility; however, their prothrombin fragments 1 (F1, residues 1-156) did—0-gla F1 moved slower than 1-gla F1. Employing anti (normal) prothrombin sera with Ca2+ , the two, 0− and 1-gla, F1’s produced vaguely visible immunoprecipitates which were definitely lighter than all the other F1’s including 2-gla. These results confirm that not only are multiple forms of atypical prothrombin induced by dicoumarol but also that gla does affect the immunochemical properties of the gla-containing fragment.

scholarly journals Effect of tunicamycin on epidermal glycoprotein and glycosaminoglycan synthesis in vitro

1981 ◽  
Vol 198 (2) ◽  
pp. 331-338 ◽  
Author(s):  
Ian A. King ◽  
Anne Tabiowo
Keyword(s):  
Amino Acids ◽  
Plasma Membrane ◽  
Cell Adhesion ◽  
Epidermal Cell ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Membrane Glycoproteins ◽  
Glycosaminoglycan Synthesis ◽  
Core Proteins

1. When pig ear skin slices were cultured for 18h in the presence of 1mug of tunicamycin/ml the incorporation of d-[3H]glucosamine into the epidermis, solubilized with 8m-urea/5% (w/v) sodium dodecyl sulphate, was inhibited by 45–55%. This degree of inhibition was not increased by using up to 5mug of tunicamycin/ml or by treating the skin slices with tunicamycin for up to 8 days. The incorporation of (U-14C)-labelled l-amino acids under these conditions was not affected by tunicamycin. Polyacrylamide-gel electrophoresis indicated that the labelling of the major glycosaminoglycan peak with d-[3H]glucosamine was unaffected, whereas that of the faster migrating glycoprotein components was considerably decreased in the presence of tunicamycin. 2. Subcellular fractionation indicated that tunicamycin specifically inhibited the incorporation of d-[3H]glucosamine but not of (U-14C)-labelled l-amino acids into particulate (mainly plasma-membrane) glycoproteins by about 70%. The labelling of soluble glycoproteins was hardly affected. Polyacrylamide-gel electrophoresis of the plasma-membrane fraction showed decreased d-[3H]glucosamine incorporation into all glycoprotein components, indicating that the plasma-membrane glycoproteins contained mainly N-asparagine-linked oligosaccharides. 3. Cellulose acetate electrophoresis of both cellular and extracellular glycosaminoglycans showed that tunicamycin had no significant effect on the synthesis of the major component, hyaluronic acid. However, the incorporation of both d-[3H]glucosamine and 35SO42− into sulphated glycosaminoglycans was inhibited by about 50%. This inhibition was partially overcome, at least in the cellular fraction, by 2mm-p-nitrophenyl β-d-xyloside indicating that tunicamycin-treated epidermis retained the ability to synthesize sulphated glycosaminoglycan chains. Tunicamycin may affect the synthesis and/or degradation of proteoglycan core proteins or the xylosyltransferase. 4. Electron-microscopic examination of epidermis treated with tunicamycin for up to 4 days revealed no significant changes in cell-surface morphology or in epidermal-cell adhesion. Either N-asparagine-linked carbohydrates play little role in epidermal-cell adhesion or more probably there is little turnover of these components in epidermal adhesive structures such as desmosomes and hemidesmosomes during organ culture.

Sign in / Sign up

Export Citation Format

Share Document