scholarly journals Factors influencing the release of proteins by cultured schwann cells

1981 ◽  
Vol 91 (3) ◽  
pp. 666-672 ◽  
Author(s):  
DJ Carey ◽  
RP Bunge
Keyword(s):  
Schwann Cells ◽  
Culture Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Qualitative Difference ◽  
Defined Medium ◽  
Normal Pattern ◽  
Fourfold Increase ◽  
Molecular Weights ◽  
Sds Page ◽  
Cultured Schwann Cells

Cultured rat schwann cells grown in association with sensory neurons when labeled with [(3)H]leucinem, [(3)H]glucosamine, or [(35)S]methionine release labeled polypeptides into the culture medium. Analysis by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of the culture medium reveals a reproducible pattern of more than 20 polypeptides with molecular weights ranging from 15,000 to more than 250,000. Five major polypeptides (apparent molecular weights 225,000, 210,000, 90,000, 66,000, 50,000, and 40,000) account for approximately 40 percent of the leucine or methionine radioactivity in medium polypeptide. Schwann cells grown in a serum-free defined medium, in which schwann cells do not relate normally to axons, release approximately four times less labeled medium polypeptides tha cultures grown in medium supplemented with serum and chick embryo extract. In addition, there is a qualitative difference in the pattern of medium polypeptides resolved by SDS-PAGE, so that a single polypeptide (mol wt 40,000) accounts for nearly all of the label in medium polypeptides. Switching of cultures grown in defined medium to supplemented medium for 2 d results in a fourfold increase in the amount of labeled polypeptides appearing in the culture medium, and a return to the normal pattern of medium polypeptides appearing in the culture medium, and a return to the normal pattern of medium polypeptides as resolved by SDS-PAGE. This change in the pattern of polypeptides release by schwann cells is accompanied by changes in the association between schwann cells and axons. An early step in the establishment of normal axon-schwann cell relations appears to be an inward migration of schwann cells into axonal bundles and spreading of schwann cells along neurites. These changes are evident within 48 h after medium shift. Our results thus suggest that the release of proteins by schwann cells may be important for the development of normal axonal ensheathment.

scholarly journals Purification and Characterization of 2,6-β-d-Fructan 6-Levanbiohydrolase fromStreptomyces exfoliatus F3-2

2000 ◽  
Vol 66 (1) ◽  
pp. 252-256 ◽  
Author(s):  
Katsuichi Saito ◽  
Kazuya Kondo ◽  
Ichiro Kojima ◽  
Atsushi Yokota ◽  
Fusao Tomita
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Extracellular Enzyme ◽  
Molecular Weights ◽  
Sds Page ◽  
Monomeric Structure ◽  
Ph Range ◽  
Hydrolysis Of

ABSTRACT Streptomyces exfoliatus F3-2 produced an extracellular enzyme that converted levan, a β-2,6-linked fructan, into levanbiose. The enzyme was purified 50-fold from culture supernatant to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of this enzyme were 54,000 by SDS-PAGE and 60,000 by gel filtration, suggesting the monomeric structure of the enzyme. The isoelectric point of the enzyme was determined to be 4.7. The optimal pH and temperature of the enzyme for levan degradation were pH 5.5 and 60°C, respectively. The enzyme was stable in the pH range 3.5 to 8.0 and also up to 50°C. The enzyme gave levanbiose as a major degradation product from levan in an exo-acting manner. It was also found that this enzyme catalyzed hydrolysis of such fructooligosaccharides as 1-kestose, nystose, and 1-fructosylnystose by liberating fructose. Thus, this enzyme appeared to hydrolyze not only β-2,6-linkage of levan, but also β-2,1-linkage of fructooligosaccharides. From these data, the enzyme from S. exfoliatus F3-2 was identified as a novel 2,6-β-d-fructan 6-levanbiohydrolase (EC 3.2.1.64 ).

scholarly journals Effects of Wheat Bug (Eurygasterspp. andAeliaspp.) Infestation in Preharvest Period on Wheat Technological Quality and Gluten Composition

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Aleksandra M. Torbica ◽  
Jasna S. Mastilović ◽  
Milica M. Pojić ◽  
Žarko S. Kevrešan
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Wheat Gluten ◽  
Sodium Dodecyl ◽  
Deformation Energy ◽  
Wheat Varieties ◽  
Gluten Proteins ◽  
Molecular Weights ◽  
Sds Page ◽  
Technological Quality ◽  
Gluten Index

The effects of wheat bug infestation (Eurygasterspp. andAeliaspp.) on the composition of wheat gluten proteins and its influence on flour technological quality were investigated in the present study. Wheat samples of six wheat varieties, collected from two localities in northern Serbia, were characterized by significantly different level of wheat bug infestation. Composition of wheat gluten proteins was determined using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), while the selected parameters of technological quality were determined according to standard and modified empirical rheological methods (Farinograph, Extensograph, Alveograph, and Gluten Index). The surface morphology of the selected samples was viewed using scanning electron microscopy (SEM). Wheat from wheat bug-infested locality regardless of the variety had deteriorated technological quality expressed with higher Farinograph softening degree, lower or immeasurable Extensograph energy, and Alveograph deformation energy. The most important changes in the gluten proteins composition of bug-infested wheat were related to gliadin subunits with molecular weights below 75 kDa, which consequently caused deterioration of uniaxial and biaxial extensibility and dough softening during mixing.

scholarly journals Schistosomula of Schistosoma mansoni clear concanavalin A from their surface by sloughing.

1982 ◽  
Vol 94 (2) ◽  
pp. 355-362 ◽  
Author(s):  
J C Samuelson ◽  
J P Caulfield ◽  
J R David
Keyword(s):  
Schistosoma Mansoni ◽  
Concanavalin A ◽  
Binding Sites ◽  
Culture Medium ◽  
Culture Media ◽  
Lectin Binding ◽  
Defined Medium ◽  
Con A ◽  
Sds Page ◽  
Lectin Binding Sites

The lectin concanavalin A (Con A) was used as a model probe to study the behavior of molecules bound to the surface of recently transformed schistosomula of Schistosoma mansoni. Con A binding was saturable (150-180 pg/organism) and specifically competed by alpha-methyl mannoside. Both FITC-Con A and 125-I-Con A were lost from the surface of schistosomula with a halftime of 8-10 h in culture in defined medium. A comparable decrease in the binding of Con A to schistosomula cultured and then labeled with the lectin indicated that the labeling procedure itself was not inducing the observed change. Internalization of Con A was not seen by either fluorescence microscopy or electron microscope radioautography. In addition, 70-80% of the radioactivity lost from the parasite was recoverable by TCA precipitation from the culture medium as intact Con A (27,000 mol wt on SDS PAGE). Thus, the mechanism of clearance of bound Con A from the surface of cultured schistosomula is apparently by sloughing of Con A molecules intact into the culture media and not by endocytosis and degradation. Con A binding sites, visualized with hemocyanin by scanning electron microscopy, appeared homogeneously distributed over the surface of schistosomula when organisms were labeled at 4 degree C or after fixation with glutaraldehyde. However, Con A and hemocyanin formed aggregates on the surface of schistosomula when labeling was performed at 37 degrees C, which suggests that lectin binding sites have lateral mobility within the plane of the membrane. These aggregates are likely independent of metabolism by the parasite because aggregation also occurs on the surface of organisms killed with azide.

An osteonectinlike protein in porcine periodontal ligament and its synthesis by periodontal ligament fibroblasts

1984 ◽  
Vol 62 (6) ◽  
pp. 470-478 ◽  
Author(s):  
Safia Wasi ◽  
Kichibee Otsuka ◽  
Kam-Ling Yao ◽  
Pierre S. Tung ◽  
Jane E. Aubin ◽  
...  
Keyword(s):  
Periodontal Ligament ◽  
Culture Medium ◽  
Alveolar Bone ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Relative Mass ◽  
Bovine Bone ◽  
Binding Studies ◽  
Periodontal Ligament Fibroblasts ◽  
Sds Page

Periodontal ligament, a soft connective tissue that lies between cementum and alveolar bone in the periodontium, has been shown to contain an osteonectinlike protein. The similarity between porcine ligament osteonectin and bovine bone osteonectin was evident from immunochemical studies, from migration characteristics on sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE) and from binding studies on hydroxyapatite. Using immunotransfer and immunodot analyses, ligament osteonectin was found to be extractable from tissues with 4 M guanidine–HCl (GuHCl) and 4 M GuHCl − 0.5 M EDTA and to comigrate with authentic bovine osteonectin on SDS–PAGE with a relative mass ~ 38 000. Furthermore, osteonectin from guanidine extracts of ligament was bound to hydroxyapatite in the presence of 4 M GuHCl. Immunofluorescence studies showed the osteonectin to be distributed throughout the extracellular matrix of the ligament and to be present within the ligament fibroblasts in a perinuclear, punctate distribution. Biosynthesis of osteonectin by ligament fibroblasts was studied following pulse-chase labelling with [35S]methionine and immunoprecipitation. The labelled osteonectin in the chased culture medium represented ~0.5% of the total labelled proteins secreted. It comigrated on SDS–PAGE with the corresponding labelled protein from pulsed cells and with the protein extracted from the tissue.

Acid and alkaline phosphatases of Capnocytophaga species. II. Isolation, purification, and characterization of the enzymes from Capnocytophaga ochracea

1983 ◽  
Vol 29 (10) ◽  
pp. 1361-1368 ◽  
Author(s):  
Thomas P. Poirier ◽  
Stanley C. Holt
Keyword(s):  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Alkaline Phosphatases ◽  
Purification And Characterization ◽  
Molecular Weights ◽  
Sds Page ◽  
Kinetics Of

Capnocytophaga ochracea acid (AcP; EC 3.1.3.2) and alkaline (AlP; EC 3.1.3.1) phosphatase was isolated by Ribi cell disruption and purified by sodium dodecyl sulphate – polyacrylamide gel electrophoresis (SDS–PAGE.) Both phosphatases eluted from Sephadex G-150 consistent with molecular weights (migration) of 140 000 and 110 000. SDS–PAGE demonstrated a 72 000 and 55 000 subunit molecular migration for AcP and AlP, respectively. The kinetics of activity of purified AcP and AIP on p-nitrophenol phosphate and phosphoseryl residues of the phosphoproteins are presented.

scholarly journals Synthesis of proteins from [35S]methionine by guinea pig megakaryocytes in vivo and time course of appearance of newly synthesized proteins in platelets

Blood ◽  
1990 ◽  
Vol 76 (5) ◽  
pp. 887-891 ◽  
Author(s):  
BP Schick
Keyword(s):  
Protein Synthesis ◽  
Guinea Pigs ◽  
Time Course ◽  
Protein Pattern ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Molecular Weights ◽  
Sds Page ◽  
Relationship Of

The relationship of protein synthesis to megakaryocyte maturation has been studied in guinea pigs in vivo. Guinea pigs were injected with a single dose of [35S]methionine. Megakaryocytes and platelets were isolated daily for 4 days, and proteins from both cells were isolated by DEAE-Sephacel chromatography and analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) and fluorography. All proteins in megakaryocytes corresponding to stained bands on the SDS- PAGE gels were radiolabeled at 3 hours after injection. The greatest loss of radioactivity from the megakaryocytes occurred between 1 and 3 days after injection. Only trace labeling of platelet proteins was seen at 3 hours, representing almost entirely three bands at molecular weights 47,000, 52,000, and 66,000. At 24 hours only about 13% of the maximal labeling was present, but not all proteins were labeled. The maximal labeling was at 3 days. The pattern of labeling of platelets at 3 days was identical to that of megakaryocytes at 3 hours. The protein pattern of nonmegakaryocytic marrow cells was different from that of the platelets and megakaryocytes. Data presented here suggest that most protein synthesis in megakaryocytes is completed at least 24 hours before release of the platelets to the circulation, and suggest some specificity in the proteins that are synthesized at the terminal stages of maturation.

scholarly journals Cleavage of human von Willebrand factor by porcine pancreatic elastase

Blood ◽  
1989 ◽  
Vol 74 (2) ◽  
pp. 673-681
Author(s):  
MA Howard ◽  
T Greco ◽  
M Coghlan
Keyword(s):  
Von Willebrand Factor ◽  
Structural Changes ◽  
Polyacrylamide Gel Electrophoresis ◽  
Pancreatic Elastase ◽  
Molecular Weights ◽  
Sds Page ◽  
Porcine Pancreatic Elastase ◽  
Cofactor Activity ◽  
Von Willebrand ◽  
Willebrand Factor

von Willebrand factor (vWF) was purified from pooled normal plasma, radiolabeled with iodine then cleaved by porcine pancreatic elastase. Cleavage was monitored by sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE), SDS-agarose electrophoresis, crossed immuno- electrophoresis, ristocetin and botrocetin cofactor activities, and ristocetin and botrocetin induced binding to fixed washed platelets. Cleavage of vWF by porcine elastase was dependent on both the concentration of porcine elastase and period of incubation. Incubation of vWF with concentrations of porcine elastase greater than 20 U/mL for 30 minutes resulted in loss of the 240 Kd vWF subunit and a corresponding loss of the high molecular weight multimers and formation of fragments with molecular weights on reduced SDS-PAGE of 150, 125, 115 Kd and minor bands at 44, 28, and 24 Kd and a band at 20 Kd, which increased in intensity as either the concentration of porcine elastase or the period of incubation increased. More than 50% of the ristocetin cofactor activity was lost during a five-minute incubation of vWF with 0.56 U/mL porcine elastase when no detectable structural changes in the vWF molecule had occurred. Botrocetin cofactor activity was more resistant. Similarly botrocetin induced vWF binding to platelets was retained by a fraction produced by digestion of vWF with porcine elastase, which contained predominantly a 20 Kd fragment of vWF. This fragment retained insignificant amounts of ristocetin related functions and therefore represents a useful piece of the vWF molecule for further exploration of the site involved in botrocetin induced binding to platelets.

scholarly journals ANALYSIS OF PROTEIN CONCENTRATE FROM KAHAI (CARYODENDRON ORINOCENSE KARST) SEEDS CULTIVATED IN AMAZONIA OF ECUADOR

2018 ◽  
Vol 11 (6) ◽  
pp. 369
Author(s):  
Greffa J ◽  
Vilcacundo E ◽  
Altuna J ◽  
Carrillo W
Keyword(s):  
Extraction Method ◽  
Colorimetric Assay ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Heat Extraction ◽  
Precipitation Method ◽  
Protein Concentrate ◽  
Native Page ◽  
Molecular Weights ◽  
Sds Page

Objective: The aim of this study was to obtain Kahai protein concentrate from Caryodendron orinocense Karst cultivated in the Amazonic region of Ecuador, to characterize its proteins using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and native electrophoresis methods, and to determine its content of total polyphenols.Methods: Kahai seeds (C. orinocense Karst) were utilized to obtain Kahai protein concentrate at pH 3.0, pH 4.0, pH 5.0, and pH 6.0 using the isoelectric precipitation method. The proteins were characterized using the SDS-PAGE and native-PAGE electrophoresis methods. Total polyphenols were determined using the colorimetric assay method.Results: The best treatment to obtain Kahai protein concentrate was at pH 5.0 with a 21.91% yield using the cold extraction method. The best treatment was at pH 6.0 with a 11.07% yield using the heat extraction method. Kahai concentrates presented a complex profile of proteins with molecular weights between 14 and 97 kDa. It was possible to obtain at the same time polyphenols at pH 5.0 with a value of 1028.58 mg gallic acid equivalents/100 g protein of sample.Conclusion: This study suggests that Kahai protein concentrates possess a high content of proteins and polyphenols that can be used to elaborate functional foods.

scholarly journals Synthesis of proteins from [35S]methionine by guinea pig megakaryocytes in vivo and time course of appearance of newly synthesized proteins in platelets

Blood ◽  
1990 ◽  
Vol 76 (5) ◽  
pp. 887-891 ◽  
Author(s):  
BP Schick
Keyword(s):  
Protein Synthesis ◽  
Guinea Pigs ◽  
Time Course ◽  
Protein Pattern ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Molecular Weights ◽  
Sds Page ◽  
Relationship Of

Abstract The relationship of protein synthesis to megakaryocyte maturation has been studied in guinea pigs in vivo. Guinea pigs were injected with a single dose of [35S]methionine. Megakaryocytes and platelets were isolated daily for 4 days, and proteins from both cells were isolated by DEAE-Sephacel chromatography and analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) and fluorography. All proteins in megakaryocytes corresponding to stained bands on the SDS- PAGE gels were radiolabeled at 3 hours after injection. The greatest loss of radioactivity from the megakaryocytes occurred between 1 and 3 days after injection. Only trace labeling of platelet proteins was seen at 3 hours, representing almost entirely three bands at molecular weights 47,000, 52,000, and 66,000. At 24 hours only about 13% of the maximal labeling was present, but not all proteins were labeled. The maximal labeling was at 3 days. The pattern of labeling of platelets at 3 days was identical to that of megakaryocytes at 3 hours. The protein pattern of nonmegakaryocytic marrow cells was different from that of the platelets and megakaryocytes. Data presented here suggest that most protein synthesis in megakaryocytes is completed at least 24 hours before release of the platelets to the circulation, and suggest some specificity in the proteins that are synthesized at the terminal stages of maturation.

scholarly journals Variation in Resistance of Mycobacterium paratuberculosis to Acid Environments as a Function of Culture Medium

2003 ◽  
Vol 69 (11) ◽  
pp. 6833-6840 ◽  
Author(s):  
Nackmoon Sung ◽  
Michael T. Collins
Keyword(s):  
Growth Rate ◽  
Culture Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Acid Resistance ◽  
Culture Conditions ◽  
Mycobacterium Paratuberculosis ◽  
In Vitro Susceptibility ◽  
Sds Page

ABSTRACT Acid resistance of Mycobacterium paratuberculosis was examined as a function of growth conditions (i.e., in vitro growth medium and pH). M. paratuberculosis was cultured in either fatty acid-containing medium (7H9-OADC) or glycerol-containing medium (WR-GD or 7H9-GD) at two culture pHs (pHs 6.0 and 6.8). Organisms produced in these six medium and pH conditions were then tested for resistance to acetate buffer at pHs 3, 4, 5, and 6 at 20°C. A radiometric culture method (BACTEC) was used to quantify viable M. paratuberculosis cell data at various acid exposure times, and D values (decimal reduction times, or the times required to kill a 1-log10 concentration of bacteria) were determined. Soluble proteins of M. paratuberculosis grown under all six conditions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to identify proteins that may be associated with acid resistance or susceptibility. The culture medium affected growth rate and morphology: thin floating sheets of cells were observed in 7H9-OADC versus confluent, thick, waxy, and wrinkled pellicles in WR-GD. Culture medium pH affected growth rate (which was highest at pH 6.0), but it had little or no effect on D values for M. paratuberculosis at any test pH. When grown in 7H9-OADC, M. paratuberculosis was more acid resistant at all test pHs (higher D values) than when grown in WR-GD. Glycerol appeared to be the culture medium component most responsible for lower levels of M. paratuberculosis acid resistance. When glycerol was substituted for OADC in the 7H9 medium, D values were significantly lower than those of 7H9-OADC-grown M. paratuberculosis and were approximately the same as those for M. paratuberculosis grown in WR-GD medium. Comparison of the SDS-PAGE protein profiles for M. paratuberculosis cultures grown in 7H9-OADC, WR-GD, or 7H9-GD medium revealed that increased expression of 34.2- and 14.0-kDa proteins was associated with higher levels of acid resistance of M. paratuberculosis grown in 7H9-OADC medium and that 56.6- and 41.3-kDa proteins were associated with lower levels of acid resistance. This is the first report showing that in vitro culture conditions significantly affect growth characteristics, acid resistance, and protein expression of M. paratuberculosis, and the results emphasize the importance of culture conditions for in vitro susceptibility studies.

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