scholarly journals The distinguishing characteristics of the plasma membrane are its exposed proteins

1975 ◽  
Vol 147 (2) ◽  
pp. 373-376 ◽  
Author(s):  
R E Gates ◽  
D R Phillips ◽  
M Morrison
Keyword(s):  
Molecular Weight ◽  
Plasma Membrane ◽  
Gel Electrophoresis ◽  
Human Lymphocytes ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cell Types ◽  
Distinguishing Characteristic ◽  
Probe System ◽  
Normal Human

The exposed proteins of the plasma membrane of normal human lymphocytes and platelets were labelled by using the lactoperoxidase macromolecular probe system. The labelled components were separated into molecular-weight classes by sodium dodecyl sulphate--polyacrylamide-gel electrophoresis. In contrast with the report by Tanner et al. (1974), a comparison of the two cell types showed that the major labelled components in both cell types were glycoproteins and were not identical. It is concluded that the exposed proteins are probably the most distinguishing characteristic of the plasma membrane of differentiated cell types.

Plasma Membrane and Nuclear Proteins of the Goose Erythrocyte

1973 ◽  
Vol 51 (10) ◽  
pp. 1442-1447 ◽  
Author(s):  
Keith R. Shelton
Keyword(s):  
Molecular Weight ◽  
Plasma Membrane ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Nuclear Proteins ◽  
Nuclear Fraction ◽  
Nonhistone Protein ◽  
Large Molecular Weight ◽  
Goose Erythrocyte

Plasma membrane and nuclear fractions have been prepared from mature goose erythrocytes. Examination of the nonhistone protein of the nuclear fraction by sodium dodecyl sulphate – polyacrylamide gel electrophoresis reveals a limited number of molecular weight species some of which are peculiar to the nuclear fraction.Electrophoretic comparison of the goose plasma membrane proteins with those of the human erythrocyte reveals many similarities. In particular, three large molecular weight species occur in both cells. Their function appears to predate the evolutionary loss of the nucleus.

scholarly journals Microbial agglutination and lymphocyte blastogenesis potentials of isolated Achatina achatina snail lectin

2021 ◽  
Vol 9 (1) ◽  
pp. 104-113
Author(s):  
Odiegwu C.N.C ◽  
Emenuga V. N. ◽  
Ogamba S. E. ◽  
Obi C. M. ◽  
Ejike C. E.
Keyword(s):  
Molecular Weight ◽  
Affinity Chromatography ◽  
Affinity Purification ◽  
Human Lymphocytes ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cell Types ◽  
Host Cells ◽  
Protein Assay ◽  
Lymphocyte Blastogenesis

Lectins are involved in recognition phenomena and their ability to bind particular Carbohydrate structures are the key to their biological functions. Bacteria typically attaches to prospective host cell membranes in receptors with lectin like sugar specificity. This is of great importance as the adherence of bacteria to host tissue surfaces is the initial event in bacterial infection. Lectins are also known to play important roles in immune system by recognizing carbohydrates that are found exclusively on pathogens, or that are inaccessible on host cells. This ability of lectins to selectively bind or agglutinate specific sugars have made them useful tools for the characterization of certain cell types or fragments, to detect cells in different states of development, to distinguish normal from tumour cells and to separate different cell types by affinity chromatography. A total of 120 samples of local Achatina achatina snail specie were collected, authenticated at the Zoology Department of the University of Nigeria, Nsukka and 80mls of pooled crude Lectin extract was obtained. Purifications were performed on 20mls of the crude extract in three steps viz, Ammonium sulphate precipitation and Dialysis (Partial purifications), Con A Sepharose 4B affinity chromatography column (Complete purification). The affinity purified lectin was used in all the tests conducted in this research. The crude, partially and complete/affinity purified lectin extracts were subjected to Haemagglutination and Protein Assay tests. The Molecular weight was deduced by Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) method. The microbial agglutination potentials of the lectin was assessed by testing typed bacterial organisms viz, Salmonella typhimurium, Escherichia coli, Lactobacilli acidophilus, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella aeruginosa and four typed fungal organisms: Aspergillus niger, Trichophyton mentagrophytes, Candida albicans and A. flavus. The lectin’s Lymphocyte blastogenesis activities was determined by its incubation with human lymphocytes for mitogenic stimulation assay. The results of the research showed as follows: On complete/affinity purification, 15mls of pure sample containing only the high molecular weight lectin was obtained. On standardization, the respective haemagglutination tests on the crude, partially and affinity purified lectin showed preferential agglutinations with Blood group A type. Only S. typhimurium (+++), E. coli (+) and L. acidophilus (+) reacted with the lectin but in different strengths. Incubation of the lectin with lymphocytes from human serum showed that it has the ability to stimulate lymphocytes to undergo mitosis. This research has therefore succeeded in assessing the Microbial agglutination and Lymphocyte blastogenesis potentials of the isolated and characterised A. achatina snail lectin.

Heterozygous Abnormal Fibrinogen Osaka III with the Replacement of γ Arginine-275 by Histidine Has an Apparently Higher Molecular Weight γ-Chain Variant

1992 ◽  
Vol 68 (05) ◽  
pp. 534-538 ◽  
Author(s):  
Nobuhiko Yoshida ◽  
Shingi Imaoka ◽  
Hajime Hirata ◽  
Michio Matsuda ◽  
Shinji Asakura
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulfate ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Tetraacetic Acid ◽  
Fibrin Monomer ◽  
Sds Page ◽  
Thrombotic Tendency ◽  
Chain Variant

SummaryCongenitally abnormal fibrinogen Osaka III with the replacement of γ Arg-275 by His was found in a 38-year-old female with no bleeding or thrombotic tendency. Release of fibrinopeptide(s) by thrombin or reptilase was normal, but her thrombin or reptilase time in the absence of calcium was markedly prolonged and the polymerization of preformed fibrin monomer which was prepared by the treatment of fibrinogen with thrombin or reptilase was also markedly defective. Propositus' fibrinogen had normal crosslinking abilities of α- and γ-chains. Analysis of fibrinogen chains on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the system of Laemmli only revealed the presence of abnormal γ-chain with an apparently higher molecular weight, the presence of which was more clearly detected with SDS-PAGE of fibrin monomer obtained by thrombin treatment. Purified fragment D1 of fibrinogen Osaka III also seemed to contain an apparently higher molecular weight fragment D1 γ remnant on Laemmli gels, which was digested faster than the normal control by plasmin in the presence of [ethy-lenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA).

Purification and partial characterization of cysteine-glutamate transaminase from rat liver

1977 ◽  
Vol 55 (9) ◽  
pp. 958-964 ◽  
Author(s):  
M. P. C. Ip ◽  
R. J. Thibert ◽  
D. E. Schmidt Jr.
Keyword(s):  
Molecular Weight ◽  
Rat Liver ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Liver Homogenate ◽  
Polyacrylamide Gel ◽  
Gel Chromatography ◽  
Labile Hydrogen ◽  
Apparent Homogeneity

Cysteine-glutamate transaminase (cysteine aminotransferase; EC 2.6.1.3) has been purified 149-fold to an apparent homogeneity giving a specific activity of 2.09 IU per milligram of protein with an overall yield of 15%. The isolation procedures involve the preliminary separation of a crude rat liver homogenate which was submitted sequentially to ammonium sulfate fractionation, TEAE-cellulose column chromatography, ultrafiltration, and isoelectrofocusing. The final product was homogenous when examined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). A minimal molecular weight of 83 500 was determined by Sephadex gel chromatography. The molecular weight as estimated by polyacrylamide gel electrophoresis in the presence of SDS was 84 000. The purified enzyme exhibited a pH optimum at 8.2 with cysteine and α-ketoglutarate as substrates. The enzyme is inactivated slowly when kept frozen and is completely inactivated if left at room temperature for 1 h. The enzyme does not catalyze the transamination of α-methyl-DL-cysteine, which, when present to a final concentration of 10 mM, exhibits a 23.2% inhibition of transamination of 30 mM of cysteine. The mechanism apparently resembles that of aspartate-glutamate transaminase (EC 2.6.1.1) in which the presence of a labile hydrogen on the alpha-carbon in the substrate is one of the strict requirements.

Novel Catalatic Proteins of Bakers' Yeast. I. An Atypical Catalase

1973 ◽  
Vol 51 (11) ◽  
pp. 1551-1555 ◽  
Author(s):  
Tony C. M. Seah ◽  
A. R. Bhatti ◽  
J. G. Kaplan
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Native Protein ◽  
Wild Type ◽  
Major Band ◽  
Subunit Molecular Weight ◽  
Purification And Properties

At any stage of growth of a wild-type bakers' yeast, some 20% of the catalatic activity of crude extracts is not precipitable by means of antibody prepared against the typical catalase (catalase T), whose purification and properties have been previously described. Some of this catalatic activity is due to the presence of an atypical catalase (catalase A), a heme protein, with a molecular weight estimated as 170 000 – 190 000, considerably lower than that of the usual catalases (225 000 – 250 000). Preparations of catalase A were found to be homogeneous in the analytical ultracentrifuge and in polyacrylamide gel electrophoresis. Its subunit molecular weight, determined from its iron content, was 46 500, virtually the same as that of the major band obtained in gel electrophoresis in the presence of sodium dodecyl sulfate, suggesting that the native protein is tetrameric. Its specific activity is in the range of those reported for other typical catalases.

Variation in goat fibre protein

1989 ◽  
Vol 40 (3) ◽  
pp. 675 ◽  
Author(s):  
DJ Tucker ◽  
AHF Hudson ◽  
A Laudani ◽  
RC Marshall ◽  
DE Rivett
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulfate ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Apparent Molecular Weight ◽  
Wool Fibre ◽  
Two Dimensional ◽  
Protein Patterns ◽  
Cashmere Goats

The proteins from a range of cashmere, mohair, angoratcashmere crossbred and wool fibre samples were extracted at pH 8 with 8 M urea containing dithiothreitol, and were then radiolabelled by S-carboxymethylation using iodo(2-14C) acetate. The proteins from each sample were examined by two dimensional polyacrylamide gel electrophoresis in which the separation in the first dimension was according to charge at pH 8.9 and in the second dimension according to apparent molecular weight in the presence of sodium dodecyl sulfate. After electrophoresis the proteins were detected by fluorography. Protein differences in keratin samples from some individual goats existed, although the overall protein patterns were similar. None of the differences were consistent with any one goat fibre type. The protein patterns obtained for fibre samples from individual cashmere goats showed some differences when compared to those found for commercial blends from the same country of origin, indicating that blending can mask any animal-to-animal variation. While the electrophoretic technique does not unequivocally distinguish between cashmere, mohair and angora/cashmere crossbred fibres it does differentiate between wool and goat fibres.

Catabolism of streptokinase and polyethylene glycol-streptokinase: evidence for transport of intact forms through the biliary system in the mouse

Blood ◽  
1990 ◽  
Vol 76 (1) ◽  
pp. 73-79 ◽  
Author(s):  
FH Brucato ◽  
SV Pizzo
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Gel Electrophoresis ◽  
Proteinase Inhibitors ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gi Tract ◽  
Substantial Fraction ◽  
Sds Page ◽  
Derivatives Of

Abstract The catabolism of streptokinase (SK) and polyethylene glycol derivatives of SK (PEG-SK) were studied in mice. The clearance and catabolism of SK:plasmin (SK:Pm) and PEG-SK:Pm activator complexes were also investigated. Native 125I-SK cleared rapidly (t1/2 = 15 minutes) from the circulation, with the majority of the ligand accumulating in the liver and gastrointestinal (GI) tract and a substantial fraction also localizing in the kidneys. SK, which was removed from the plasma by the liver, was secreted into bile and then the GI tract. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that 125I-SK recovered from liver and bile was homogeneous and of the same molecular weight (mol wt approximately 50,200) as native SK. PEG-125I-SK cleared slowly (t1/2 greater than 200 minutes), with more than 80% of the preparation localizing in liver and GI tract. The PEG-125I-SK secreted into the bile was also intact. The bile containing 125I-SK was incubated with stoichiometric amounts of plasminogen and electrophoresed under nondenaturing conditions. This study demonstrated that the secreted SK was able to form SK:Pg complexes. SDS-PAGE also showed activation of 125I-Pg that was incubated with recovered bile containing the SK. 125I-SK:Pm catabolism was also studied. In these experiments, the mol wt approximately 42,000 fragment obtained when SK is cleaved by plasmin was found in the bile. This fragment of 125I-SK was not recovered as part of a complex with plasmin, consistent with our previous observations that catabolism of SK:Pm involves transfer of the plasmin to plasma proteinase inhibitors while SK is catabolized independently. By contrast, when PEG-125I-SK:Pm was injected into mice, only intact PEG-125I-SK was found in the bile, consistent with our previous observations that the PEG derivatization blocks its degradation by plasmin.

The isolation of surface array proteins from bacteria

1984 ◽  
Vol 62 (11) ◽  
pp. 1181-1189 ◽  
Author(s):  
S. F. Koval ◽  
R. G. E. Murray
Keyword(s):  
Molecular Weight ◽  
Protein Conformation ◽  
Gel Electrophoresis ◽  
Guanidine Hydrochloride ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Structural Features ◽  
Proteolytic Degradation ◽  
Low Concentrations ◽  
Single Polypeptide

The methods used for the isolation of regularly structured (RS) surface array proteins of a range of prokaryotes are described. Most RS proteins can be selectively solubilized from envelope preparations with low concentrations of urea or guanidine hydrochloride. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis analysis of the protein extracts shows that most RS arrays are composed of a single polypeptide that may contain carbohydrate. The molecular weight of the proteins varies from 41 000 to 200 000. Possible reasons for the presence of more than one polypeptide in RS protein preparations are discussed, as well as the evidence for proteolytic degradation of some RS proteins during isolation. Structural features of the RS proteins are described and the importance of protein conformation to assembly of the arrays is indicated.

Sign in / Sign up

Export Citation Format

Share Document