scholarly journals Determination of the molecular weights of actins from different species by gel chromatography

1972 ◽  
Vol 127 (3) ◽  
pp. 75P-76P
Author(s):  
F B Preston ◽  
G N Graham
Keyword(s):  
Gel Chromatography ◽  
Molecular Weights

Plasmin Digestion of factor VIII: Characterization of the Breakdown Products with Respect to Antigenicity and von Willebrand Activity

1978 ◽  
Vol 40 (02) ◽  
pp. 302-315 ◽  
Author(s):  
J A Guisasola ◽  
C G Cockburn ◽  
R M Hardisty
Keyword(s):  
Factor Viii ◽  
Biological Activities ◽  
Molecular Size ◽  
Progressive Increase ◽  
Gel Chromatography ◽  
Molecular Weights ◽  
Von Willebrand ◽  
Ristocetin Cofactor

SummaryHighly purified factor VIII was incubated for up to 24 hours in the presence of plasmin, and the biological activities and peptide structure of the digestion products determined at intervals. Procoagulant activity (VIIIC) was rapidly lost, but 17-32% of the initial ristocetin cofactor (VIIIR: WF) activity remained after 24 hours. Immunoelectrophoresis showed a progressive increase in rocket height and a concomitant increase in electrophoretic mobility of the factor-VIII-related antigen (VIIIR: AG). Crossed immunoelectrophoresis of the 24- hour digest showed three distinct precipitin arcs, of which the major one, with intermediate anodal mobility, gave reactions of non-identity with the other two. On sepharose gel chromatography the 24-hour digest gave three peaks: peak II contained about 80% of the residual VIIIR: WF and resolved on SDS-polyacrylamide gels into a series of peptides with apparent molecular weights between 125,000 and 185,000; these were reduced by mercaptoethanol to fragments of 15,000-80,000 daltons, a 65,000 dalton fragment being particularly strongly PAS positive. We conclude that large molecular size is not a prerequisite for VIIIR :WF activity, and that the presence of factor-VIII breakdown products may be a cause of misleading results in the determination of VIIIR:AG by immunoelectrophoresis.

Transmission Electron Microscopy of Protein Macromolecules

1971 ◽  
Vol 29 ◽  
pp. 424-425
Author(s):  
Henry S. Slayter
Keyword(s):  
Biological Systems ◽  
Metal Vapor ◽  
Resolving Power ◽  
Electron Microscopic ◽  
Chemical Methods ◽  
Molecular Weights ◽  
The Past ◽  
Physical Chemical ◽  
Transmission Electron

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.

Low Molecular Weight Trypsin-Plasmin Inhibitors Isolated from Papain Treated Urinary Trypsin Inhibitor

1982 ◽  
Vol 47 (01) ◽  
pp. 014-018 ◽  
Author(s):  
H Sumi ◽  
N Toki ◽  
S Takasugi ◽  
S Maehara ◽  
M Maruyama ◽  
...  
Keyword(s):  
Trypsin Inhibitor ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Chromatography ◽  
Urinary Trypsin Inhibitor ◽  
Plasmin Activity ◽  
Molecular Weights ◽  
Plasmin Inhibitors

SummaryPapain treatment of human urinary trypsin inhibitor (UTI67; mol. wt. 43,000 by SDS-polyacrylamide gel electrophoresis, specific activity 1,897 U/mg protein) produced four new protease inhibitors, which were highly purified by gel chromatography on Sephadex G-100 and isoelectric focusing. The purified inhibitors (UTI26, UTI9-I, UTI9-II, and UTI9-III) were shown to be homogeneous by polyacrylamide disc gel electrophoresis, and had apparent molecular weights of 26,000, 9,000, 9,000, and 9,800, respectively, by sodium dodecyl sulfate gel electrophoresis. During enzymatic degradation of UTI67, the amino acid compositions changed to more basic, and the isoelectric point increased from pH 2.0 (UTI67) to pHs 4.4, 5.2, 6.6, and 8.3 (UTI26, UTI9-I, UTI9-II, and UTI9-III), respectively. Both the parent and degraded inhibitors had anti-plasmin activity as well as antitrypsin and anti-chymotrypsin activities. Much higher anti-plasmin/anti-trypsin and anti-plasmin/anti-chymotrypsin activities were observed in the degraded inhibitors than in the parent UTI67. They competitively inhibited human plasmin with Ki values of 1.13 X 10-7 - 2.12 X 10-6 M (H-D-Val-Leu-Lys-pNA substrate). The reactions were very fast and the active site of the inhibitors to plasmin was thought to be different from that to trypsin or chymotrypsin.

Preparation of graft copolymers by the reaction of polymeric acyl chlorides with monohydroxy-terminated polymers: An introductory study

1988 ◽  
Vol 53 (8) ◽  
pp. 1735-1744 ◽  
Author(s):  
Jitka Horská ◽  
Jaroslav Stejskal ◽  
Pavel Kratochvíl ◽  
Aubrey D. Jenkins ◽  
Eugenia Tsartolia ◽  
...  
Keyword(s):  
Light Scattering ◽  
Chemical Composition ◽  
Statistical Model ◽  
Graft Copolymers ◽  
Coupling Reaction ◽  
Molecular Characteristics ◽  
Gel Formation ◽  
Acyl Chlorides ◽  
Molecular Weights

An attempt was made to prepare well-defined graft copolymers by the coupling reaction between acyl chloride groups located along the backbone chain and monohydroxy-terminated grafts prepared separately. The molecular weights and the parameters of heterogeneity in chemical composition of the products were determined by light scattering and osmometry. The determination of molecular characteristics revealed that the degree of grafting was low. The results therefore could not be confronted with a statistical model at this stage. The problems encountered in the synthesis, e.g., gel formation, and the data relating to the soluble products are discussed.

Characterization of Glycoprotein Fraction from Carp Pituitaries Isolated Using Concanavalin A as the Affinity Ligand

1998 ◽  
Vol 63 (3) ◽  
pp. 434-440 ◽  
Author(s):  
Irena Hulová ◽  
Jana Barthová ◽  
Helena Ryšlavá ◽  
Václav Kašička
Keyword(s):  
Concanavalin A ◽  
Reversed Phase ◽  
Amino Acid Sequences ◽  
Gel Chromatography ◽  
Affinity Ligand ◽  
Sds Page ◽  
Terminal Amino ◽  
Α And Β Subunits

Glycoproteins that have affinity to Concanavalin A were isolated from the acetone-dried pituitaries of common carp (Cyprinus carpio L.). Two fractions of glycoproteins were separated using gel chromatography on Superdex 75HR. The fraction with lower molecular weight (30 000) corresponding to the carp gonadotropin cGtH II was composed of two subunits as determined using SDS-PAGE. This protein fraction was further divided into four components using reversed-phase HPLC. Two fractions were pure α and β subunits of cGtH II as follows from immunodetection and from determination of N-terminal amino acid sequences. The other two were a mixture of α and β subunits as was also revealed by N-terminal analysis. Capillary electrophoresis was also used for characterization of isolated glycoproteins.

scholarly journals The apparent molecular weights of human intestinal aminopeptidase, enterokinase and maltase in native duodenal fluid

1977 ◽  
Vol 165 (3) ◽  
pp. 583-585 ◽  
Author(s):  
A I Magee ◽  
D A W Grant ◽  
J Hermon-Taylor
Keyword(s):  
Molecular Form ◽  
Gel Chromatography ◽  
Duodenal Fluid ◽  
Molecular Weights ◽  
Induced Changes

The apparent molecular weights of human intestinal aminopeptidase, enterokinase and maltase in native duodenal fluid were estimated by gel chromatography on Sephadex G-200 under different conditions of operational buffer and temperature. No evidence for environmentally induced changes in molecular form was found.

Determination of molecular weights by the archibald method using absorption optics

1969 ◽  
Vol 30 (2) ◽  
pp. 212-216 ◽  
Author(s):  
K. de Groot ◽  
J.C.M. Reijnen ◽  
H.J. Hoenders
Keyword(s):  
Molecular Weights
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