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K Waśniowska

Publications and source records attributed to K Waśniowska.

At least 19 recordsLinked to original sources
PubMed2001

Juvenile hormone binding protein and transferrin from Galleria mellonella share a similar structural motif.

It has been previously suggested that juvenile hormone binding protein(s) (JHBP) belongs to a new class of proteins. In the search for other protein(s) that may contain structural motifs similar to those found in JHBP, hemolymph from Galleria mellonella (Lepidoptera) was chromatographed over a Sephadex G-200 column and resulting fractions were subjected to SDS-PAGE, transferred onto nitrocellulose membrane and scanned with a monoclonal antibody, mAb 104, against hemolymph JHBP. Two proteins yielded a positive reaction with mAb 104, one corresponding to JHBP and the second corresponding to a transferrin, as judged from N-terminal amino acid sequencing staining. Transferrin was purified to about 80% homogeneity using a two-step procedure including Sephadex G-200 gel filtration and HPLC MonoQ column chromatography. Panning of a random peptide display library and analysis with immobilized synthetic peptides were applied for finding a common epitope present in JHBP and the transferrin molecule. The postulated epitope motif recognized by mAb 104 in the JHBP sequence is RDTKAVN, and is localized at position 82-88.

Amino Acid Motifs↗
PubMed2000

Expression and binding properties of a soluble chimeric protein containing the N-terminal domain of the Duffy antigen.

The blood group Duffy antigen of human erythrocytes, which exists in two allelic forms, Fy(a) and Fy(b), is a promiscuous chemokine receptor. In this report we describe the expression and purification of a chimeric protein composed of the amino-terminal extracellular domain of the Duffy antigen (aa 3-60), C-terminal intracellular fragment of glycophorin A (GPA, aa 104-131), and the hexahistydyl tag. We obtained two forms of the recombinant protein containing the Fy(a) or Fy(b) epitope, denoted Fy(a)/GPA and Fy(b)/GPA, respectively. These constructs were expressed in Escherichia coli as periplasmic proteins and were purified by affinity chromatography on the Ni-NTA-agarose. Both proteins bound the monoclonal antibodies recognizing the common Fy6 epitope of the Duffy antigen and an epitope of the C-terminal fragment of GPA, and only the Fy(a)/GPA bound anti-Fy(a) antibody. However, binding of IL-8 to the recombinant proteins was not detected, which indicated that an N-terminal domain of the Duffy antigen is not sufficient for an effective chemokine binding. The lack of the chemokine binding was not likely to be due to the lack of glycosylation of the Fy/GPA, since IL-8 was effectively bound to de-N-glycosylated erythrocytes.

Amino Acid Sequence↗
PubMed1999

[Human chemokine receptors: structure and function].

Chemokines are relatively small peptides with potent chemoattractant and activation activities for leukocytes. Several chemokine receptors, belonging to the G proteincoupled receptor superfamily, have been cloned and characterized and their functions have been partially elucidated.

Chemokines↗
PubMed1997

Mapping of peptidic epitopes of glycophorins A (GPA) and C (GPC) with peptides synthesized on plastic pins (Pepscan analysis).

The peptidic epitopes of 12 anti-GPA and 4 anti-GPC antibodies were identified with the use of peptides synthesized on the pins. Most of the antibodies were specific for epitopes located in extracellular portion of glycophorins, and only 2 anti-GPA and 1 anti-GPC recognized epitopes in their C-terminal cytoplasmic tails. The extracellular GPA epitopes were located in two regions of the polypeptide chain, within a.a. residues 38-44 and 49-58.

Antibodies, Monoclonal↗
PubMed1996

Identification of the Fy6 epitope recognized by two monoclonal antibodies in the N-terminal extracellular portion of the Duffy antigen receptor for chemokines.

The epitope Fy6 recognized by two monoclonal antibodies (i3A and BG6), which inhibit binding of chemokines to the Duffy antigen, was characterized by means of peptides synthesized on pins (Epitope Scanning Kit) and deletion mutagenesis. Both antibodies showed very similar specificities. They recognized a linear epitope, the essential portion of which was the heptapeptide Gln-Leu-Asp-Phe-Glu-Asp-Val comprising amino acid residues 21-27, located between two glycosylation sites of the Duffy protein. All the amino acid residues of the epitope, except Glu, were essential for antibody binding, since they could not be replaced by any other amino acid residues or by only one or two. The Glu residue could be replaced by most other amino acid residues, and its replacement by 10 amino acid residues gave a distinct increase in the antibody binding. The results were in full agreement with the finding that the mutant of the Duffy antigen, lacking amino acid residues 23-25 (-Asp-Phe-Glu-), did not bind the i3A antibody, but bound the anti-Fy3 monoclonal antibody similarly to the wild type of the Duffy antigen. The apparent affinity constants of both anti-Fy6 antibodies were determined by surface plasmon resonance, using immunopurified Duffy protein as a ligand.

Amino Acid Sequence↗
PubMed1992

Analysis of peptidic epitopes recognized by the three monoclonal antibodies specific for the same region of glycophorin A but showing different properties.

Analysis of epitopes for the three monoclonal antibodies (GPA105, GPA33, OSK4-1) against glycophorin A (GPA) was performed with the use of proteolytic fragments of GPA, the synthetic nonapeptide with the sequence of amino acid residues 35-43 of GPA, and a series of peptides synthesized on plastic pins. The antibodies were specific for a short peptide sequence RAHE (a.a. 39-42 of GPA, MAbs GPA105 and OSK4-1) or RAHEV (a.a. 39-43 of GPA, MAb GPA33). Despite recognizing the same fragment of GPA, the three antibodies showed differences in fine specificity and in response to antigen desialylation. Reactions with single replacement analogs of the RAHEV sequence showed that immunodominant (unreplaceable) residues for the MAbs GPA33 and OSK4-1 were His and Glu, respectively, whereas no such residue was found for the MAb GPA105. Desialylation of the antigen gave strong enhancement of reactivity with the MAb GPA33, moderate--with the MAb GPA105, and weak or no enhancement of reaction with the MAb OSK4-1. The results showed that monoclonal antibodies directed against the same fragment of the polypeptide chain of densely glycosylated antigen may recognize different subsites which are masked at different degree by sialic acid residues.

Amino Acid Sequence↗
PubMed1988

Degradation of the human erythrocyte membrane band 3 studied with monoclonal antibody directed against an epitope on the cytoplasmic fragment of band 3.

The mouse hybridoma monoclonal antibody BIII.136 of the IgG2a class is specific for human erythrocyte band-3 protein. It was shown by means of immunoblotting and immunoprecipitation assays that the antibody recognized an epitope located in the cytoplasmic pole of the band-3 molecule within approximately 20 kDa from the N-terminal end. The N-terminal fragments of band-3 protein, migrating in SDS/polyacrylamide gel electrophoresis in the 60-kDa, 40-kDa and 20-kDa regions, were detected with the antibody in untreated red-cell membranes as products of autolysis of band-3 protein. A correlation was found between the amount of these fragments and erythrocyte age, which suggests that partial degradation of band 3 proceeds in vivo during senescence of erythrocytes. The further degradation of band-3 protein in vitro was not observed in intact erythrocytes stored at 4 degrees C, but progressed distinctly after hemolysis of red cells, during washing and storing the membranes.

Anion Exchange Protein 1, Erythrocyte↗
PubMed1988

Two monoclonal antibodies recognizing different epitopes of blood group N antigen.

Two monoclonal antibodies, N/61 (IgG2b) and N/92 (IgG2a), reacting preferentially with blood group N antigen, were obtained by immunization of BALB/c mice with human red cell membrane glycophorins. The antibodies showed distinctly different specificities. N/61 reacted with an epitope with NH2-terminal Leu residue, its free amino group, and sialic acid residues as essential components. The antibody N/92 reacted equally well with untreated and desialylated N glycoprotein, but did not react with de-O-glycosylated antigen. It seemed to recognize an epitope including both blood group N-characteristic amino acid residues, namely the 1st Leu and 5th Glu. The antibodies also differed in pH-dependence. N/61 showed maximal activity at pH 6-7 with tendency to decrease at higher pH values, whereas N/92 was not or weakly active up to pH 7, and showed a strong increase of activity at pH range 7-8.

Agglutination↗
PubMed1984

Characterization of anti-treponemal lymphotoxin from lymphocytes of syphilitic rabbits.

The effect of various treatments on the activity of anti-treponemal lymphotoxin (ATL) produced by lymphocytes of syphilitic rabbits was studied. Treponema pallidum-killing activity of ATL was slightly reduced after heating at 56 degrees C and completely abolished at 100 degrees C. The significant reduction of the activity was also obtained after exposure of ATL to acidic conditions (pH 1-5) at room temperature, or by treatment with papain and neuraminidase. Activity of ATL was completely resistant to deoxyribonuclease, ribonuclease and trypsin treatment. ATL was eluted from the Sephadex G-100 column together with hemoglobin, that suggested the apparent molecular weight of ATL of about 65,000. The active fraction from the Sephadex G-100 column was further fractionated on DEAE-Sephadex A-50. The activity of ATL was widely spread in the column eluate, indicating the charge heterogeneity. All these data indicate that ATL is a relatively low molecular weight protein. The sensitivity to neuraminidase and heterogeneity of charge suggest that it is a glycosylated protein.

Animals↗
PubMed1983

Purification of peanut agglutinin by affinity chromatography on asialoglycophorin from human erythrocytes.

A simple and efficient method of purification of peanut agglutinin is described. This method involves affinity chromatography on human asialoglycophorin linked to Affi-Gel. One milliliter of the packed adsorbent contained 1.7 mg of covalently linked asialoglycophorin and bound about 6 mg of the peanut agglutinin. From 250 g of row peanuts 510 mg of the electrophoretically homogeneous lectin with high agglutinating activity was obtained.

Asialoglycoproteins↗
PubMed1981

Products of digestion of tryptic M and N blood group glycopeptides with pronase.

Digestion of tryptic M and N blood group glycopeptides with pronase generated a heterogeneous mixture of smaller glycopeptides. Two NH2-terminal glycopeptides, composed of 26--28 and 18--19 amino acid residues, and three fractions containing several glycopeptides deriving from the COOH-terminal portion of tryptic glycopeptides were obtained. The characterization of pronase glycopeptides showed that most of the peptide bonds hydrolyzed by pronase were susceptible to proteolysis only in part of molecules of tryptic glycopeptides, most probably due to a microheterogeneity in their glycosylation. The similar sets of pronase glycopeptides were obtained from tryptic M and N glycopeptides, indicating that the possible heterogeneity in their glycosylation is independent of the blood group type. Only the NH2-terminal glycopeptides showed M and N blood group activity, and only the NH2-terminal glycopeptides obtained from tryptic N glycopeptide reacted with Vicia graminea anti-N lectin.

Epitopes↗
PubMed1980

Circular dichroism studies of M and N blood group-specific glycoproteins and glycopeptides.

CD spectra of M and N blood group glycoproteins and their NH2-terminal tryptic glycopeptides were compared. The CD spectra of glycoproteins obtained suggest the presence of a low content of alpha-helix. The M glycoprotein contained a higher percentage of a periodical structure. CD spectra of M and N tryptic glycopeptides, both sialoglycopeptides and desialylated preparates, were similar and showed positive ellipticities in the range of 210--240 m. However, the spectra of desialylated glycopeptides were red-shifted in respect to spectra of sialoglycopeptides. The CD spectra of glycopeptides suggest the presence of beta-turns.

Circular Dichroism↗
PubMed1978

Immunochemical characterization of cyanogen bromide degradation products of M and N blood-group glycopeptides.

The major glycopeptides purified from the tryptic digests of M and N blood-group glycoproteins were degraded with cyanogen bromide into two fragments. The chemical composition and serological activities of the fragments obtained were determined. The results show that M and N blood-group determinants are located on the smaller N-terminal fragments, containing 8 amino acid residues and only alkali-labile oligosaccharide chains. Two of 8 amino acid residues are different in M-specific and N-specific glycopeptide. All glycopeptides obtained inhibited Vicia graminea anti-N lectin, but the N-terminal fragment of N-glycopeptide was a better inhibitor than others. Treatment with neuraminidase or acetylation of amino groups destroyed the M and N blood-group activity and increased the activity towards Vicia graminea anti-N lectin of all glycopeptides studied.

Amino Acids↗
PubMed1978

Localization and immunochemical characterization of the lectin Evonymous europaeus receptor site on the glycoprotein from human O erythrocytes.

Purified and desialylated glycoprotein M from human O erythrocytes precipitates with B and H specific lectin from Evonymous europaeus seeds, both in PBS and 0.2% Triton X-100. Desialylated, N-terminal fragment (MT-1) obtained by trypsin digestion of M glycoprotein does not precipitate with Evonymous lectin but inhibits precipitation.

ABO Blood-Group System↗