Isolation, characterization and localization of a lectin within the vitelline membrane of the hen's egg

Development ◽  
1985 ◽  
Vol 90 (1) ◽  
pp. 389-407
Author(s):  
Geoffrey M. W. Cook ◽  
Ruth Bellairs ◽  
Nicholas G. Rutherford ◽  
Caroline A. Stafford ◽  
Thomas Alderson

A lectin with an affinity for certain sulphated polysaccharides, such as fucoidin and dextran sulphate, has been isolated from the vitelline membrane of hens' eggs and purified to homogeneity as assessed by two-dimensional gel electrophoresis. Polyclonal and monoclonal antibodies have been raised to the lectin and used in indirect immunofluorescence microscopy to localize the agglutinin in the outer layer of the vitelline membrane, where the lectin persists prior to the breakdown of the vitelline membrane. The quantity of lectin extracted from the two layers of the membrane, which have been separated by the method of Bellairs, Harkness & Harkness (1963), correlated well with the results of immunofluorescence microscopy. Sodium dodecyl sulphate—polyacrylamide gel electrophoresis of the two layers of the membrane indicates that each layer has a distinctive polypeptide composition, the outer layer containing in particular lysozyme and avidin. The evidence obtained in this study indicates that the lectin is not involved in adhesion of the blastoderm to the vitelline membrane; neither is it involved in the expansion of the blastoderm nor in maintaining the strength of the membrane. The possible roles in promoting transport of solutes across the membrane as well as providing bactericidal properties to the egg are discussed.

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Areeba Ahmad ◽  
Riaz Ahmad

AbstractTwo-dimensional gel electrophoresis (2DE) separating proteins on the basis of their pI and molecular mass remain the best available technique for protein separation and characterization to date. But due to several limitations, including streak formation in IEF gels, partial solubility of proteins, expensive running conditions and relatively longer time taken, a simple urea-SDS-2D polyacrylamide gel electrophoresis (US2DE) is described here. The system is reasonably sensitive, cost effective with good reproducibility. The method described in this paper employs a chaotropic agent, urea, in the first dimension and sodium dodecyl sulphate (SDS), like conventional system, in the second dimension with an addition of polyacrylamide to screen the liver proteome of healthy and chemically induced fibrotic rats. The system separates the protein on the basis of chargeto- mass ratio and clearly demonstrates differential expression in the liver protein repertoire of healthy and fibrotic rats. Moreover, the present system, like other 2D electrophoretic procedures revealed at least 22 novel spots in the investigated tissues. The technique may be utilized for comprehensive proteome screening of any biological sample and would provide an overview to narrow down the candidate proteins or biomarkers.


Blood ◽  
2001 ◽  
Vol 98 (13) ◽  
pp. 3626-3634 ◽  
Author(s):  
Venke Skibeli ◽  
Gro Nissen-Lie ◽  
Peter Torjesen

Abstract Erythropoietin (EPO) from sera obtained from anemic patients was successfully isolated using magnetic beads coated with a human EPO (hEPO)–specific antibody. Human serum EPO emerged as a broad band after sodium dodecyl sulfate–polyacrylamide gel electrophoresis, with an apparent molecular weight slightly smaller than that of recombinant hEPO (rhEPO). The bandwidth corresponded with microheterogeneity because of extensive glycosylation. Two-dimensional gel electrophoresis revealing several different glycoforms confirmed the heterogeneity of circulating hEPO. The immobilized anti-hEPO antibody was capable of binding a representative selection of rhEPO glycoforms. This was shown by comparing normal-phase high-performance liquid chromatography profiles of oligosaccharides released from rhEPO with oligosaccharides released from rhEPO after isolation with hEPO-specific magnetic beads. Charge analysis demonstrated that human serum EPO contained only mono-, di-, and tri-acidic oligosaccharides and lacked the tetra-acidic structures present in the glycans from rhEPO. Determination of charge state after treatment of human serum EPO with Arthrobacter ureafaciens sialidase showed that the acidity of the oligosaccharide structures was caused by sialic acids. The sugar profiles of human serum EPO, describing both neutral and charged sugar, appeared significantly different from the profiles of rhEPO. The detection of glycan structural discrepancies between human serum EPO and rhEPO by sugar profiling may be significant for diagnosing pathologic conditions, maintaining pharmaceutical quality control, and establishing a direct method to detect the misuse of rhEPO in sports.


1980 ◽  
Vol 26 (9) ◽  
pp. 1317-1322 ◽  
Author(s):  
D Goldman ◽  
C R Merril ◽  
M H Ebert

Abstract Two-dimensional electrophoresis, with isoelectric focusing in the first dimension and sodium dodecyl sulfate/polyacrylamide gel electrophoresis in the second, has been adapted for the high-resolution analysis of cerebrospinal fluid proteins. Proteins were detected with a new, highly sensitive silver stain that made visible more than 300 polypeptides from 60 microL of spinal fluid, in highly reproducible patterns. We have mapped these patterns, noting difference between the proteins observed in spinal fluid and plasma, and have prepared a partial map of cerebrospinal fluid proteins.


2004 ◽  
Vol 70 (2) ◽  
pp. 679-685 ◽  
Author(s):  
Martha Lara ◽  
Luis Servín-González ◽  
Mahavir Singh ◽  
Carlos Moreno ◽  
Ingrid Cohen ◽  
...  

ABSTRACT The gene encoding the 45/47 kDa glycoprotein (Rv1860) of Mycobacterium tuberculosis was expressed in Streptomyces lividans under its own promoter and under the thiostrepton-inducible Streptomyces promoter PtipA . The recombinant protein was released into the culture medium and, like the native protein, migrated as a double band at 45 and 47 kDa in sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) gels. However, in contrast to the native protein, only the 47-kDa recombinant protein could be labeled with concanavalin A (ConA). Carbohydrate digestion with jack bean α-d-mannosidase resulted in a reduction in the molecular mass of the recombinant protein upper band and completely eliminated ConA binding. Two-dimensional gel electrophoresis revealed only one isoelectric point for the recombinant protein. Comparative fingerprinting analysis of the individually purified upper and lower recombinant protein bands, treated under the same conditions with specific proteases, resulted in similar peptide patterns, and the peptides had the same N-terminal sequence, suggesting that migration of the recombinant protein as two bands in SDS-PAGE gels could be due to differences in glycosylation. Mass spectrometry analysis of the recombinant protein indicated that as in native protein, both the N-terminal and C-terminal domains of the recombinant protein are glycosylated. Furthermore, it was determined that antibodies of human tuberculosis patients reacted mainly against the carbohydrate residues of the glycoprotein. Altogether, these observations show that expression of genes for mycobacterial antigens in S. lividans is very useful for elucidation of the functional role and molecular mechanisms of glycosylation in bacteria.


1989 ◽  
Vol 76 (5) ◽  
pp. 547-552 ◽  
Author(s):  
A. Argiles ◽  
G. Mourad ◽  
C. Axelrud-Cavadore ◽  
A. Watrin ◽  
C. Mion ◽  
...  

1. Protein constituents were determined in eight amyloid deposits from eight patients (five male and three female), 53 ± 4 years of age, treated by haemodialysis for 9-20 years using only cuprophane membranes and operated for carpal tunnel syndrome. 2. Soluble proteins were removed by solubilization in phosphate-buffered saline after osmotic lysis. The proteins of the insoluble fibrils were characterized by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and two-dimensional gel electrophoresis, and immunologically identified by Western blotting. 3. In addition to β2-microglobulin, α2-macroglobulin was identified in the fibrillar material. The presence of these two proteins in amyloid deposits was confirmed by immunofluorescent microscopic studies. 4. Our data confirm the presence of β2-microglobulin in haemodialysis-associated amyloidosis, and also suggest a possible role for α2-microglobulin: it may protect β2-microglobulin from proteolytic digestion, leading to its accumulation in intact form and to amyloid fibril formation.


1985 ◽  
Vol 231 (1) ◽  
pp. 197-199 ◽  
Author(s):  
S C Smith ◽  
W McAdam ◽  
R G H Cotton ◽  
J F B Mercer

Two-dimensional gel electrophoresis of immunopurified monkey liver phenylalanine hydroxylase showed a novel form of the enzyme, in 4 out of 24 monkeys, in which each polypeptide spot was split into a doublet with the same charge but slightly different mobility in the sodium dodecyl sulphate/polyacrylamide-gel-electrophoresis (as opposed to the isoelectric-focusing) dimension. Phenylalanine hydroxylase formed by translation of RNA from a liver containing the novel form showed the doublet pattern, suggesting that it is due to differences in mRNA. By analogy with the rat, this mRNA difference could be due to allelic genes.


1976 ◽  
Vol 54 (1) ◽  
pp. 9-14 ◽  
Author(s):  
G. Jackowski ◽  
D. Suria ◽  
C. C. Liew

Isolation of nucleolar proteins was obtained by dissociation in the presence of urea – guanidine hydrochloride, followed by high-speed centrifugation to remove nucleic acids. At least 31 fractions of nucleolar proteins were detected by isoelectrofocusing gel electrophoresis in the pH range 3.5–10. Following two-dimensional gel electrophoresis on sodium dodecyl sulfate – polyacrylamide slab gels, more than 100 components of nucleolar proteins were identified. Two-thirds of nucleolar proteins were located in the pH range 5–8 following isoelectrofocusing. The molecular weights of these classes of proteins were shown to be mostly 30 000 – 70 000 by sodium dodecyl sulfate – polyacrylamide gel electrophoresis.


2007 ◽  
Vol 73 (7) ◽  
pp. 2037-2047 ◽  
Author(s):  
Ji Youn Lim ◽  
Haiqing Sheng ◽  
Keun Seok Seo ◽  
Yong Ho Park ◽  
Carolyn J. Hovde

ABSTRACT Escherichia coli O157:H7 causes hemorrhagic colitis and hemolytic-uremic syndrome in humans, and its major reservoir is healthy cattle. An F-like 92-kb plasmid, pO157, is found in most E. coli O157:H7 clinical isolates, and pO157 shares sequence similarities with plasmids present in other enterohemorrhagic E. coli serotypes. We compared wild-type (WT) E. coli O157:H7 and an isogenic ΔpO157 mutant for (i) growth rates and antibiotic susceptibilities, (ii) survival in environments with various acidity, salt, or heat conditions, (iii) protein expression, and (iv) survival and persistence in cattle following oral challenge. Growth, metabolic reactions, and antibiotic resistance of the ΔpO157 mutant were indistinguishable from those of its complement and the WT. However, in cell competition assays, the WT was more abundant than the ΔpO157 mutant. The ΔpO157 mutant was more resistant to acidic synthetic bovine gastric fluid and bile than the WT. In vivo, the ΔpO157 mutant survived passage through the bovine gastrointestinal tract better than the WT but, interestingly, did not colonize the bovine rectoanal junction mucosa as well as the WT. Many proteins were differentially expressed between the ΔpO157 mutant and the WT. Proteins from whole-cell lysates and membrane fractions of cell lysates were separated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional gel electrophoresis. Ten differentially expressed ∼50-kDa proteins were identified by quadrupole-time of flight mass spectrometry and sequence matching with the peptide fragment database. Most of these proteins, including tryptophanase and glutamate decarboxylase isozymes, were related to survival under salvage conditions, and expression was increased by the deletion of pO157. This suggested that the genes on pO157 regulate some chromosomal genes.


1995 ◽  
Vol 15 (7) ◽  
pp. 3579-3586 ◽  
Author(s):  
A Eilers ◽  
D Georgellis ◽  
B Klose ◽  
C Schindler ◽  
A Ziemiecki ◽  
...  

Gamma interferon (IFN-gamma), a macrophage-activating cytokine, modulates gene expression through the activity of a transcription factor designated IFN-gamma activation factor (GAF). GAF is formed after phosphorylation on tyrosine and dimerization of the 91-kDa protein STAT1. We have recently reported that differentiation of the promonocytic cell line U937 into monocytes increases the amount of cellular GAF after IFN-gamma treatment and at the same time increases the phosphorylation of STAT1. Here we show that activation of the JAK family kinases, which are instrumental in mediating STAT1 phosphorylation on tyrosine, did not increase upon monocytic U937 differentiation. Consistent with this finding, levels of STAT1 tyrosine phosphorylation were virtually identical in promonocytic and monocytic U937 cells. Analysis of STAT1 phosphoamino acids and mapping of phosphopeptides showed an IFN-gamma-dependent increase in Ser phosphorylation in differentiated cells. Analyses of STAT1 isoforms by two-dimensional gel electrophoresis demonstrated a differentiation-induced shift toward more acidic isoforms. All isoforms were equally sensitive to subsequent tyrosine phosphorylation, as indicated by a sodium dodecyl sulfate-polyacrylamide gel electrophoresis mobility shift typical for tyrosine-phosphorylated STAT1. Consistent with the importance of Ser phosphorylation for high-affinity binding to the IFN-gamma activation site sequence, phosphatase 2A treatment strongly reduced the formation of IFN-gamma activation site-GAF complexes in an electrophoretic mobility shift assay. Our data indicate that the activity of GAF is modulated by STAT1 serine kinases/phosphatases and suggest that this mechanism is employed in the developmental control of macrophage responsiveness to IFN-gamma.


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