scholarly journals Protein and glycoprotein antifreezes in the intestinal fluid of polar fishes

1982 ◽  
Vol 98 (1) ◽  
pp. 429-438
Author(s):  
S. M. O'Grady ◽  
J. C. Ellory ◽  
A. L. DeVries
Keyword(s):  
North Atlantic ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Low Molecular Weight ◽  
Intestinal Fluid ◽  
Melting Points ◽  
Ion Concentrations ◽  
Freezing Points ◽  
Antarctic Fishes ◽  
The Antarctic

Measurements of ion concentrations, freezing points and melting points of intestinal fluid were made for several Antarctic fishes and two North Atlantic species. These measurements indicated that plasma and intestinal fluid are nearly isosmotic. Freezing points of intestinal fluid were approximately 0.9 degrees C below the melting points, suggesting the presence of glyco-protein antifreeze within the intestinal fluid of the Antarctic fishes. Polyacrylamide gel electrophoresis and specific immunoprecipitation with glyco-protein antifreeze antibody confirmed the presence of appreciable quantities of antifreeze and showed that the major antifreeze fractions present in the intestinal fluid are low molecular weight glycopeptides.

Normal Mature Human Enamel Protein

1979 ◽  
Vol 58 (2_suppl) ◽  
pp. 986-987 ◽  
Author(s):  
A. Belcourt
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Gel Electrophoresis ◽  
Protein Concentration ◽  
Polyacrylamide Gel Electrophoresis ◽  
Organic Matrix ◽  
Low Molecular Weight ◽  
Human Enamel ◽  
Weak Density ◽  
Enamel Protein

Pure enamel was prepared using an original microdissection technic. Protein concentration was 375 μg per gram of enamel. Polyacrylamide gel electrophoresis showed a single fast-migrating zone containing a thin double band. Ultracentrifugation studies suggested that the proteins were of low molecular weight or of weak density. Absorption spectra showed a strong absorbance at 260nm. Amino acid analyses yielded a composition of 25% Gly, 13.5% Glu, 11% Ser, 11% Pro, 2% Cys and 2% Hyp. A glucidic content of 15% was estimated and glucose, galactose, mannose and fucose were identified. The organic matrix of enamel seemed to be constituted of two major glycoproteins probably fibrous but different from keratin.

scholarly journals Serological grouping ofTreponema hyodysenteriae

1990 ◽  
Vol 105 (1) ◽  
pp. 79-85 ◽  
Author(s):  
D. J. Hampson ◽  
J. R. L. Mhoma ◽  
B. G. Combs ◽  
J. I. Lee
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Vaccine Development ◽  
Polyacrylamide Gel Electrophoresis ◽  
Cross Reactivity ◽  
Low Molecular Weight ◽  
Serological Response ◽  
Double Immunodiffusion ◽  
Sds Page ◽  
Treponema Hyodysenteriae

SUMMARYTwo Australian isolates ofTreponema hyodysenteriaewhich did not fit within the current serological grouping system for these bacteria wrere examined by agarose gel double immunodiffusion tests (AGDP). Isolate Vic1 was serologically unique, and we propose that it becomes the type organism for a new sixth serological group ofT. hyodysenteriae(Group F). Isolate Q1 was unusual in that lipopolysaccharide (LPS) extracted from it reacted strongly in AGDP with serum raised against the type organism for serogroup D (A1), and also weakly with serum raised against the type organism for serogroup B (WA1). The nature of this cross-reactivity was examined by using cross-absorbed antisera in AGDP, and by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis.The pattern of serological cross-reactivity between Q1, A1 and WA1 was complex and was not fully defined, but the isolate Q1 apparently shared low molecular weight ‘serogroup’ LPS antigens with A1, and shared higher molecular weight LPS antigens with WA1. On this basis Q1 was designated as belonging to serogroup D, although it was recommended that this be qualified as D (B) to indicate the presence of weak cross-reactivity with serogroup B. Such serological cross-reactivity may have significance in relation to the development of immunity toT. hyodysenteriae. Isolate Q1 may be a potentially useful organism for vaccine development because of its ability to induce a good serological response to LPS of treponemes from both serogroups D and B.

scholarly journals Suicidal inactivation and labelling of ammonia mono-oxygenase by acetylene

1985 ◽  
Vol 227 (3) ◽  
pp. 719-725 ◽  
Author(s):  
M R Hyman ◽  
P M Wood
Keyword(s):  
Protective Effect ◽  
Gel Electrophoresis ◽  
Ammonia Oxidation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Competitive Inhibitor ◽  
Ion Concentrations ◽  
First Order ◽  
First Order Kinetics ◽  
Labelling Experiment ◽  
Suicide Substrate

Acetylene brings about a progressive inactivation of ammonia mono-oxygenase, the ammonia-oxidizing enzyme in Nitrosomonas europaea. High NH4+ ion concentrations were protective. The inactivation followed first-order kinetics, with a rate constant of 1.5 min-1 at saturating concentrations of acetylene. If acetylene was added in the absence of O2, the cells remained active until O2 was re-introduced. A protective effect was also demonstrated with thiourea, a reversible non-competitive inhibitor of ammonia oxidation. Incubation of cells with [14C]acetylene was found to cause labelling of a single membrane polypeptide. This ran on dodecyl sulphate/polyacrylamide-gel electrophoresis with an Mr value of 28 000. It is concluded that acetylene is a suicide substrate for the mono-oxygenase. The labelling experiment provides the first identification of a constituent polypeptide of ammonia mono-oxygenase.

Membrane Glycoprotein Defects In Bernard-Soulier Syndrome Platelets

1981 ◽  
Author(s):  
K J Clemetson ◽  
J L McGregor ◽  
E James ◽  
M Dechavanne ◽  
E F Lüscher
Keyword(s):  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Galactose Oxidase ◽  
Low Molecular Weight ◽  
Membrane Glycoprotein ◽  
One Dimensional ◽  
The Third ◽  
Healthy Donors ◽  
Bernard Soulier Syndrome

It is well established that Bernard-Soulier syndrome (BSS) platelets are deficient in a major membrane glycoprotein (lb). In order to investigate if this is the only defect in this disorder and to see if the β-subunit of glycoprotein lb is also diminished, platelets from 3 BSS patients and from healthy donors were isolated, washed and surface labelled by lactoperoxidase-catalysed iodination, pèriodate/NaB3H4 or neuraminidase/ galactose oxidase/NaB3H4. Labelled platelets were solubilized in sodium dodecyl sulphate and separated by 2-dimensional gel electrophoresis (isoelectric focusing, discontinuous polyacrylamide gel electrophoresis). Glycoprotein Ibα was virtually absent in 2 patients and strongly decreased in the third patient. The 3-subunit was also absent in the 2 patients and present at about 40 % of normal in the third. Glycoprotein IIbβ was present normally in all patients. In addition, a further low molecular weight glycoprotein with a M.WT. of 17,000 and a pI of 6.8-7.5 was absent or present at levels paralleling glycoprotein Ibβ. The thrombin cleavable glycoprotein (GP IV or V) appeared greatly diminished with BSS platelets labelled by carbo-hydrate specific methods though no difference could be seen with iodination. This finding was confirmed in a fourth BSS patient using one dimensional gel electrophoresis.The defects in BSS platelets are thus more complex than previously thought.

Fractionation of Chromatin Components

1973 ◽  
Vol 51 (5) ◽  
pp. 709-720 ◽  
Author(s):  
John J. Monahan ◽  
Ross H. Hall
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Deae Cellulose ◽  
Polyacrylamide Gel ◽  
Urea Solution ◽  
Equilibrium Density ◽  
Tissue Culture Cell ◽  
Low Molecular Weight ◽  
Nonhistone Proteins

A general method for isolation and fractionation of chromatin into its four major components, DNA, RNA, histories, and nonhistone proteins, is described. The procedure avoids the use of strongly acidic or alkaline conditions, or the use of ionic detergents or phenol. As few as 14 × 106 cells can be used. The procedure is reasonably rapid and has been used successfully with a number of tissue culture cell lines. The chromatin components are dissociated in a 3 M NaCl – 5 M urea solution containing 2-mercaptoethanol and EDTA. The DNA and high molecular weight RNA are collected by high-speed centrifugation and DNA is separated from the RNA by means of Cs2SO4 equilibrium density centrifugation. The histones, nonhistone proteins, and low molecular weight RNA's are fractionated using DEAE-cellulose column chromatography and polyacrylamide gel electrophoresis. A small amount (< 1%) of protein is present in the DNA and RNA fractions. At least 11 low molecular weight RNA subfractions can be detected by means of polyacrylamide gel electrophoresis.

Effects of Thrombin, Chymotrypsin and Aggregated Gamma-Globulins on the Proteins of the Human Platelet Membrane

1977 ◽  
Vol 37 (03) ◽  
pp. 396-406 ◽  
Author(s):  
B Podolsak
Keyword(s):  
Molecular Weight ◽  
Platelet Activation ◽  
Gel Electrophoresis ◽  
Human Platelet ◽  
Polyacrylamide Gel Electrophoresis ◽  
Platelet Membrane ◽  
Low Molecular Weight ◽  
Membrane Glycoproteins ◽  
Membrane Component ◽  
Before And After

SummaryAnalysis of platelet membrane proteins and glycoproteins by SDS Polyacrylamide gel electrophoresis was carried out before and after treatment with thrombin. Extended incubation with thrombin (in the presence of EDTA or adenosine, which inhibit aggregation) produced extensive changes in the bands observed. With incubation times of a few minutes however, the changes were restricted to a glycopeptide, GP IV (approx. 90,000 Daltons) and one or two polypeptides of low molecular weight, in particular polypeptide 16 (approx. 23,000 Daltons). At 0–3° C only polypeptide 16 was still hydrolyzed.Chymotrypsin, which does not activate platelets, attacked glycopeptides I, II, III but no changes were apparent in GP IV and polypeptide 16. When chymotrypsin-treated platelets were further incubated with thrombin, only GP IV and one to two low molecular weight polypeptides, especially polypeptide 16, were affected. As polypeptide 16 appears to be an integral membrane component it is possible that it, either by itself or in combination with GP IV, represents the primary thrombin substrate involved in platelet activation.Aggregated IgG, which also activates platelets, does not modify the membrane glycoproteins but does change the low molecular weight region in particular band 16.

Analysis of proteins in rabbit pulmonary surfactant using monoclonal antibodies

1986 ◽  
Vol 250 (3) ◽  
pp. C460-C467 ◽  
Author(s):  
R. J. King ◽  
H. M. Martin ◽  
J. B. Baseman ◽  
J. Morrison-Plummer
Keyword(s):  
Molecular Weight ◽  
Monoclonal Antibodies ◽  
High Molecular Weight ◽  
Gel Electrophoresis ◽  
Pulmonary Surfactant ◽  
Polyacrylamide Gel Electrophoresis ◽  
Low Molecular Weight ◽  
Weight Group ◽  
Molecular Weights ◽  
Intermediate Group

We have used monoclonal antibodies developed against the apolipoproteins associated with pulmonary surfactant purified from rabbit lavage fluid to study the expression of epitopes common to these proteins. The pulmonary surfactant contained nearly 20 proteins, of which at least 10 were not derived from serum. Electrophoresis, with sulfhydryl reduction of these proteins indicated apparent molecular weights of approximately 155, 135, 125, and 115 X 10(3) (high-molecular-weight group); 80, 70, and 60 X 10(3) (intermediate group); and 18 through 10 X 10(3) (low-molecular-weight group). Two-dimensional polyacrylamide gel electrophoresis, in which the proteins were electrophoresed without reduction in the first dimension, but with sulfhydryl reduction in the second dimension, revealed that the 80, 70, and 60 X 10(3) proteins dissociated into proteins of nominal molecular weights of 40, 35, and 30 X 10(3), respectively. In contrast, the 125 and 115 X 10(3) proteins of the high-molecular-weight group contained a protein which could only be reduced to a minimum molecular weight of 55 to 60 X 10(3). Monoclonal antibodies generally were of three types: those that reacted strongly with the high-molecular-weight group and weakly with the intermediate group; those that reacted conversely; and those that reacted only with the low-molecular-weight group. Our results indicate that at least two different surfactant apolipoproteins, with differing minimum molecular weights in SDS-polyacrylamide gel electrophoresis, have common epitopes. Although these results cannot certify a physiological relationship between these proteins, they suggest that the intracellular synthesis or extracellular processing of surfactant apolipoproteins may be more complicated than predicted by the findings of previous experiments, perhaps involving the posttranslational assembly of one surfactant protein into oligomers which resist dissociation under the conditions used for the analyses.

Method for measuring the concentration of urinary proteins according to their molecular size category.

1976 ◽  
Vol 22 (5) ◽  
pp. 667-672 ◽  
Author(s):  
A J Pesce ◽  
A Hsu ◽  
C Kornhauser ◽  
K Sethi ◽  
B S Ooi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Low Molecular Weight ◽  
Tubular Proteinuria ◽  
Equal Concentration ◽  
Glomerular Proteinuria ◽  
Low Molecular Weight Proteins

Abstract We combined the use of a concentrating device (Minicon) and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate to semi-quantitate the concentration of (a) the collective low-molecular-weight proteins and (b) of albumin excreted in the urine of patients after renal transplantation. Analytical recovery of many serum proteins from samples concentrated 100-fold in the Minicon apparatus was about 70%. It was possible to examine many urine samples by polyacrylamide gel electrophoresis after concentration with this device. The reproducibility (CV) of the technique was on the order of 20% when albumin and low-molecular-weight protein were in about equal concentration. The method was adequate to differntiate glomerular and tubular proteinuria, because in glomerular proteinuria the ratio of albumin to low-molecular-weight proteins is about 20/1, whereas in tubular proteinuria the ratio is about 1/1.

scholarly journals Synthesis of a low molecular weight collagen by chondrocytes from the presumptive calcification region of the embryonic chick sterna: the influence of culture with collagen gels.

1984 ◽  
Vol 99 (1) ◽  
pp. 208-216 ◽  
Author(s):  
G J Gibson ◽  
B W Beaumont ◽  
M H Flint
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Collagen Synthesis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Morphological Features ◽  
Low Molecular Weight ◽  
Type Ii ◽  
Embryonic Chick ◽  
Collagen Gels ◽  
Discrete Populations

The mature chick sternum is divisible almost equally into cephalic calcified and caudal cartilagenous regions. Isolation and culture of cells derived from embryonic precursors of these regions has revealed two discrete populations of cells with distinct morphological features and synthetic capabilities. Both cell populations grew well in culture within or upon collagen gels or upon plastic and maintained morphologies similar to those observed in the parent tissue. Polyacrylamide gel electrophoresis of radiolabeled proteins synthesized by the cells in culture demonstrated large differences in the types of collagens synthesized. Both chondrocyte populations synthesized type II and minor cartilage collagens but only chondrocytes isolated from the presumptive calcification region synthesized the previously identified, low molecular weight collagen, termed G collagen. Synthesis of G collagen was stimulated by culture within or upon collagen gels such that it represented an average of 65% of the total collagen synthesized by presumptive calcification region chondrocytes after 7 d of culture within collagen gels. Light and scanning electron microscopy demonstrated that the two chondrocyte types exhibited distinct morphological features and accumulated different extracellular matrices in culture.

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