Concanavalin A-horseradish peroxidase bridge staining of alpha-1 glycoproteins separated by isoelectric focusing on polyacrylamide gel.

1976 ◽  
Vol 24 (8) ◽  
pp. 908-914 ◽  
Author(s):  
R C Allen ◽  
S S Spicer ◽  
D Zehr

The Coomassie Blue protein stain and the periodic acid-Schiff stain for glycoproteins are compared to a new method of staining glycoproteins resolved electrophoretically. The method utilizes a Concanavalin A-horseradish peroxidase sequence to visualize selectively glycoproteins with terminal or internal mannose or terminal N-acetylglucosamine. The method applied to characterization of M and Z allele products of alpha-l-antitrypsins separated by isoelectric focusing of polyacrylamide gels slabs have revealed differences in carbohydrate content of various components that were previously undetected.

1983 ◽  
Vol 31 (6) ◽  
pp. 709-716 ◽  
Author(s):  
M R Green

Proteins in colostrum and skimmed milk from humans and mice were separated by electrophoresis on polyacrylamide gels and stained with Coomassie blue (CB), Ethyl-Stains-all (ESA), and periodic acid-Schiff (PAS) to investigate changes that may occur in milks throughout lactation. In mouse colostrum but not in mature mouse milk, a PAS-positive protein of apparent molecular weight of 60,000 stained prominently blue with ESA. A protein in human milk with a molecular weight of 68,000 stained similarly but was present throughout lactation. The intensity of blue staining of these minor proteins in milk approached that obtained with casein phosphoproteins. The metachromatic dye ESA stains phosphoproteins and sialic acid-rich glycoproteins blue to blue-green. Removal of phosphorus from the former and sialic acid from the latter results in those proteins staining red with ESA. The intensity of blue staining of the 60,000 and 68,000 Mr proteins was diminished but not lost following treatment with phosphatase. It was eliminated following neuraminidase digestion of the mouse protein and mild acid hydrolysis of the human protein. Coomassie blue staining of the proteins was not affected by these procedures. Following electrophoresis of milk and milk fractions in a non-sodium dodecyl sulfate-containing system, the proteins were identified by their characteristic staining properties with ESA and isolated.


1979 ◽  
Vol 177 (1) ◽  
pp. 153-158 ◽  
Author(s):  
Saura Sahu ◽  
William S. Lynn

A high-molecular-weight glycoprotein was isolated, purified and partially characterized from the insoluble pulmonary secretions accumulating in lungs of patients suffering from pulmonary alveolar proteinosis. On electrophoresis in 5% polyacrylamide gel in the presence of sodium dodecyl sulphate and 2-mercaptoethanol, the purified protein gave one major band as detected by Coomassie Blue as well as with periodic acid/Schiff staining. An apparent mol.wt. of 250000 was estimated for this glycoprotein. Amino acid analysis showed that it contains hydroxyproline, and relatively high amounts of glycine, glutamic acid, aspartic acid and leucine. It contains approx. 6% hexose, 3% sialic acid and 2% glucosamine. The neutral sugars are galactose, mannose and fucose. An antiserum prepared in rabbits against this high-molecular-weight glycoprotein cross-reacted with two smaller glycoproteins (mol.wts. 62000 and 36000) isolated from the same pulmonary secretions of these patients. A complementary observation was also made when this large alveolar glycoprotein cross-reacted with an antiserum prepared in rabbits against the smaller glycoprotein (mol.wt. 36000). It appears that this high-molecular-weight glycoprotein may be the precursor of the two smaller glycoproteins present in the same diseased pulmonary secretions.


2001 ◽  
Vol 125 (1) ◽  
pp. 141-145
Author(s):  
Rajal B. Shah ◽  
Min W. Lee ◽  
Alvaro A. Giraldo ◽  
Mahul B. Amin

Abstract Context.—We have observed intraluminal crystalloid morphology in seminal vesicles that is superficially similar to that seen in prostate neoplasia, but found little information on such morphology in the literature. Design.—Two hundred fifty-three prostate specimens (163 needle biopsies, 75 radical prostatectomies with prostate carcinoma, 11 prostates from autopsy, and 4 cystoprostatectomies without prostate carcinoma) were examined for seminal vesicle secretions, which were categorized as (a) dense platelike inspissated, (b) fluidlike, (c) crystalloid morphology, and (d) absent. Histochemical stains (periodic acid–Schiff with and without diastase, Alcian blue at pH 2.5, and mucicarmine) were performed to characterize the nature of secretions. Results.—Proteinaceous secretions were identified in 82% of seminal vesicles examined. Of these, 61% had predominantly dense, platelike, inspissated secretions, 15% had predominantly fluidlike secretions, and 24% had predominantly crystalloid morphology. Although in some cases the crystalloid morphology resembled that of prostatic intraluminal crystalloids, the seminal vesicle crystalloids differed in that they were invariably multiple, had curved edges, and had varied forms (elliptical, cylindrical, rodlike, and rectangular). Seventy-one percent of seminal vesicle crystalloids were associated with dense, platelike, inspissated secretions and appeared to be created by fracturing within platelike secretions. There was no relationship between seminal vesicle crystalloid morphology and associated malignancy in the prostate gland, as it was seen in 24% of cases with prostate carcinoma and 25% of cases without prostate carcinoma (P = 1.0000). Fluidlike secretions were positive for Alcian blue (pH 2.5) and mucicarmine, whereas dense platelike secretions and crystalloid morphology were negative for Alcian blue (pH 2.5) and mucicarmine. Conclusions.—Seminal vesicle secretions are fairly common and, when fluidlike, are composed of acid mucopolysaccharides. Inspissation of secretions appears to be associated with loss of acidity, presumably resulting in dense platelike secretions and crystallization. Awareness of both the crystalloid morphology in seminal vesicle tissue and the distinguishing features from prostatic crystalloids may be important while interpreting prostate needle biopsies in which seminal vesicle epithelium may be confused for prostate carcinoma because of a small acinar morphology with accompanying cytologic atypia and crystalloid morphology.


2018 ◽  
Vol 399 (9) ◽  
pp. 1009-1022 ◽  
Author(s):  
Shihui Guo ◽  
Peter Briza ◽  
Viktor Magdolen ◽  
Hans Brandstetter ◽  
Peter Goettig

Abstract Human kallikrein-related peptidases 3, 4, 11, and KLK2, the activator of KLK3/PSA, belong to the prostatic group of the KLKs, whose major physiological function is semen liquefaction during the fertilization process. Notably, these KLKs are upregulated in prostate cancer and are used as clinical biomarkers or have been proposed as therapeutic targets. However, this potential awaits a detailed characterization of these proteases. In order to study glycosylated prostatic KLKs resembling the natural proteases, we used Leishmania (LEXSY) and HEK293 cells for secretory expression. Both systems allowed the subsequent purification of soluble pro-KLK zymogens with correct propeptides and of the mature forms. Periodic acid-Schiff reaction, enzymatic deglycosylation assays, and mass spectrometry confirmed the glycosylation of these KLKs. Activation of glycosylated pro-KLKs 4 and 11 turned out to be most efficient by glycosylated KLK2 and KLK4, respectively. By comparing the glycosylated prostatic KLKs with their non-glycosylated counterparts from Escherichia coli, it was observed that the N-glycans stabilize the KLK proteases and change their activation profiles and their enzymatic activity to some extent. The functional role of glycosylation in prostate-specific KLKs could pave the way to a deeper understanding of their biology and to medical applications.


1981 ◽  
Vol 195 (2) ◽  
pp. 389-397 ◽  
Author(s):  
D A Wiginton ◽  
M S Coleman ◽  
J J Hutton

Adenosine deaminase was purified 3038-fold to apparent homogeneity from human leukaemic granulocytes by adenosine affinity chromatography. The purified enzyme has a specific activity of 486 mumol/min per mg of protein at 35 degrees C. It exhibits a single band when subjected to sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, non-denaturing polyacrylamide-gel electrophoresis and isoelectric focusing. The pI is 4.4. The enzyme is a monomeric protein of molecular weight 44000. Both electrophoretic behaviour and molecular weight differ from those of the low-molecular-weight adenosine deaminase purified from human erythrocytes. Its amino acid composition is reported. Tests with periodic acid-Schiff reagent for associated carbohydrate are negative. Of the large group of physiological compounds tested as potential effectors, none has a significant effect. The enzyme is specific for adenosine and deoxyadenosine, with Km values of 48 microM and 34 microM respectively. There are no significant differences in enzyme function on the two substrates. erythro-9-(2-Hydroxy non-3-yl) adenine is a competitive inhibitor, with Ki 15 nM. Deoxycoformycin inhibits deamination of both adenosine and deoxyadenosine, with an apparent Ki of 60-90 pM. A specific antibody was developed against the purified enzyme, and a sensitive radioimmunoassay for adenosine deaminase protein is described.


1979 ◽  
Vol 53 (1) ◽  
pp. 91-95 ◽  
Author(s):  
G. Massi ◽  
A. Fabiano ◽  
D. Ragusa ◽  
P. Auconi

1972 ◽  
Vol 20 (5) ◽  
pp. 368-384 ◽  
Author(s):  
ANITA C. BEEN ◽  
ELLEN M. RASCH

Proteins extracted from individual pairs of salivary glands or other larval tissues of Sciara coprophila (Diptera) were separated in a vertical microsystem for discontinuous electrophoresis using thin sheets of polyacrylamide gel cast in multiple layers of varying pore size. After electrophoresis at 150 volts for 40 min, gels were stained ( a) for total proteins with Coomassie brilliant blue, ( b) for glycoproteins with the periodic acid-Schiff reaction, ( c) for lipoproteins with Sudan black B or ( d) for nonspecific esterases with fast blue RR as coupler and α-naphthol acetate as substrate. Sequential application of these reactions to individual gel sectors permitted direct comparisons of protein profiles for 15-20 different samples of tissue extracts carried on a single gel sheet in adjacent lanes and thus subjected to identical conditions of electrophoresis. Representative photographs and densitometric scans are presented to show the suitability of thin gel sheets for autoradiography and for both qualitative and quantitative evaluation of tissue-specific differences in patterns of protein banding found for salivary gland cells, the gastric ceca, or the hemolymph of individual Sciara larvae sacrificed at particular stages of fourth instar development. Innovative details of methodology are presented, including the use of a microspectrophotometer to scan electropherograms of insect proteins and several types of human blood serum.


1985 ◽  
Vol 100 (1) ◽  
pp. 317-321 ◽  
Author(s):  
J R Okita ◽  
D Pidard ◽  
P J Newman ◽  
R R Montgomery ◽  
T J Kunicki

Glycoprotein (GP) Ib was purified from lysates of human platelets prepared in the presence or absence of inhibitors of the endogenous calcium-activated neutral protease (CANP) by immunoaffinity chromatography, employing the GPIb-specific murine monoclonal antibody, AP1, coupled to Sepharose CL4B. When derived from lysates prepared in the presence of EDTA or leupeptin, the eluate from the AP1-affinity column contained a 240,000-260,000-mol-wt protein in addition to GPIb. In SDS PAGE, this protein was stained by Coomassie Blue R, but not by the periodic acid-Schiff reagent, and it was not labeled with 125I in intact platelets by the lactoperoxidase-catalyzed method. When derived from lysates prepared in the absence of CANP inhibitors, the eluate contained only GPIb and its proteolytic derivative, glycocalicin. A change in the electrophoretic mobility of GPIb consistent with its association with the 240,000-260,000-mol-wt protein was confirmed by crossed immunoelectrophoresis. By an immunoblot technique involving transfer of proteins eluted from the AP1-affinity column and separated by SDS PAGE onto a nitrocellulose membrane, the 240,000-260,000-mol-wt protein bound polyclonal goat antibody raised against rabbit macrophage actin-binding protein (ABP). On the basis of these results, we conclude the GPIb is tightly associated with ABP under conditions in which the endogenous CANP is inhibited, and that this apparent transmembrane complex of GPIb-ABP can be isolated in lysates of nonactivated human platelets.


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