Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationship between erythrocyte autoreactive cold agglutinin (CA) antibodies and group carbohydrate-specific antibodies in hyperimmune rabbit Group C streptococcal antisera was investigated. The different antibody preparations examined were isolated from autologous erythrocyte, Group C carbohydrate, and alpha-GalNAc immunoabsorbents. Each population was subsequently tested for SRBC reactivity, RRBC autoreactivity, and carbohydrate and ligand reactivity, in hemagglutination assay, direct biphasic hemolytic and hemolytic inhibition assays, and radioimmunoassay. In absorption experiments, CA antibodies present in unfractionated serum and represented as purified IgG and IgM preparations, were reactive with Group C carbohydrate, but poorly reactive with alpha-GalNAc immunoabsorbent. In addition, CA antibody activity present in carbohydrate-eluted material, was absent in alpha-GalNAc-eluted material as determined by hemagglutination and direct hemolytic assay. By radioimmunoassay, carbohydrate-eluted and alpha-GalNAc-eluted streptococcal antibodies, and alpha-GalNAc-eluted BSA-alpha-GalNAc antibodies, exhibited similar reactivity with 125I-BSA-alpha-GalNAc antigen, and with GalNAc in radioimmunoassay inhibition experiments. In contrast to these results, both IgG and IgM CA antibodies exhibited a relatively low avidity toward 125I-BSA-alpha-GalNAc. Yet relative to the other antibody populations tested in radioimmunoassay inhibition experiments, CA antibodies did not exhibit a particularly significant difference in reactivity with GalNAc. However, recognition of other Gal-containing ligands, e.g. Mel and Lac, was restricted to the CA antibody preparations. These data suggest that CA antibodies present in Group C streptococcal antisera do not represent a higher affinity cross-reactive anticarbohydrate population, but instead perhaps represent cross-reactive carbohydrate-specific antibodies produced in response to nonimmunodominant Group C carbohydrate determinants.
Mol Immunol 1982 Mar
PMID:Properties of cold agglutinin and group carbohydrate-specific antibodies isolated from group C streptococcal antisera. 709 71

The binding of uropathogenic Escherichia coli to the globo series of glycolipids via P pili is a critical step in the infectious process that is mediated by a human-specific PapG adhesin. Three classes of PapG adhesins exist with different binding specificities to Gal alpha 4Gal-containing glycolipids. The structural basis for PapG recognition of the human glycolipid receptor globoside was investigated by using soluble saccharide analogues as inhibitors of bacterial haemagglutination. The minimum binding epitope was confirmed as the Gal alpha 4Gal moiety, but parts of the GalNAc beta and glucose residues, which flank the Gal alpha 4Gal in globoside (GbO4), were also shown to be important for strong binding. Furthermore, the same five hydroxyl groups of Gal alpha 4Gal in globotriasyl ceramide that were recognized by a previously characterized PapG variant were also recognized by the human-specific PapG in binding the GbO4 that dominates in the human kidney. Saccharide analogues that blocked haemagglutination also blocked the adherence of human uropathogenic E. coli to human kidney sections. Knowledge of the molecular details of the PapG-GbO4 interaction will make it possible to design antiadherence therapeutics.
Mol Microbiol 1995 Jun
PMID:Structural requirements for the glycolipid receptor of human uropathogenic Escherichia coli. 747 78

A method for the purification by affinity of antibodies of the IgM and IgG classes against the (Gal beta 1-->3 GalNAc-) epitope has been developed. The immunoadsorbent is based on the property of DEAE-Sephadex to bind acid glycolipids bearing this epitope, by electrostatic and hydrophobic interactions in a stable form in an aqueous medium. The acid glycolipid employed was asialo-GM1 ganglioside (GA1) derivatized to produce a carboxyl function on the olefinic bond of the sphingosine moiety (GA1 acid). The DEAE-Sephadex-GA1 acid complex was used to purify the antibodies of the IgG class from serum of an immunized rabbit and of the IgM class from a human serum. The specific activities of the purified antibodies were 1,200- to 2,400-fold higher, and the antibody activities were quantitatively recovered respect to the untreated sera, in both cases. The sequential use of two immunoadsorbents: DEAE-Sephadex-ganglioside and DEAE-Sephadex-GA1 acid, allows the separation of the two classes of immunoglobulins that recognize the same sugar residues in glycolipids.
Biochem Mol Biol Int 1994 May
PMID:Glycolipids noncovalently bound to DEAE-Sephadex. Use of the complexes for purification of IgM and IgG anti-(Gal beta 1-->3 GalNAc-) antibodies. 752 99

Two glycoproteins (205 and 72 kDa) were found in Bacillus thuringiensis sporangia. They were predominantly localized in the exosporium and/or the spore coat, although a small proportion was also found in membranes. A method for the dissociation of hydrophobic aggregates that resist the usual conditions of SDS-PAGE is described. Using this method we established that the 205 kDa glycoprotein is a multimer of the 72 kDa one. Deglycosylation of the 205 kDa and 72 kDa glycoproteins with trifluoromethanesulfonic acid yielded a 54 kDa polypeptide in both cases. At least three species of oligosaccharides were O-glycosidically linked to serines of the 54 kDa polypeptide chain. One of the oligosaccharides had N-acetylgalactosamine at the reducing end, rhamnose and a component not yet identified.
Mol Cell Biochem 1995 Apr 12
PMID:A glycoprotein multimer from Bacillus thuringiensis sporangia: dissociation into subunits and sugar composition. 765 76

To define carbohydrate specificity of Ricinus communis agglutinin (RCA1), the combining site of RCA1 was further characterized by quantitative precipitin (QPA) and precipitin-inhibition assays (QPIA). Among the oligosaccharides tested for QPIA, Gal beta 1-->4GlcNAc (II, human blood group type II precursor sequence) was found to be 7.1 times more active than Gal beta 1-->3GalNAc (T, Thomsen-Friedenreich sequence) and about 1.7 times more active than the other three disaccharides tested--Gal beta 1-->4Man, Gal beta 1-->3DAra and Gal beta 1-->6GalNAc. Gal alpha 1-->4Gal, the receptor of the uropathogenic E. coli ligand was 3.6 times less active than the II sequence. These results indicate that the beta 1-->4 linkage of the terminal Gal to subterminal GlcNAc is important as this beta 1-->4GlcNAc sequence is at least 1.6 times more active than other types of disaccharides. Among the glycoproteins examined for QPA, native and desialized bovine submandibular glycoproteins, native and desialized human plasma alpha 1-acid glycoproteins, as well as crude hog stomach mucin and its three mild acid hydrolyzed products reacted well with the lectin. These glycoproteins precipitated over 75% of the lectin nitrogen added indicating that RCA1 has the ability to recognize Gal beta 1-->4/3GlcNAc and/or the related residues at the non-reducing ends and at positions in the interior of the chains. However, Tn (GalNAc alpha 1-->Ser/Thr sequence) rich glycoproteins such as desialized ovine submandibular glycoprotein and desialized armadillo salivary glycoprotein, in which over 90% of the carbohydrate side chains are Tn determinants with none or only a trace of I/II or T determinants, precipitated poorly with RCA1. From the present and previous results obtained, the carbohydrate specificity of RCA1 can be constructed and summarized in decreasing order by lectin determinants as follows: II (Gal beta 1-->4GlcNAc) > I (Gal beta 1-->3GlcNAc) > E (Gal alpha 1-->4Gal) and B (Gal alpha 1-->3Gal) > T (Gal beta 1-->3GalNAc), while Tn (GalNAc alpha 1-->Ser/Thr) is a poor inhibitor.
Mol Immunol 1993 Mar
PMID:Defining carbohydrate specificity of Ricinus communis agglutinin as Gal beta 1-->4GlcNAc (II) > Gal beta 1-->3GlcNAc (I) > Gal alpha 1-->3Gal (B) > Gal beta 1-->3GalNAc (T). 768 Nov 48

A modified procedure for chemical deglycosylation of glycoproteins containing sialylated and/or O-linked oligosaccharides, using anhydrous trifluoromethane sulfonic acid (TFMSA) is described. Although sialic acid residues are acid labile, it has been known that anhydrous TFMSA does not effectively remove carbohydrate side chains from glycoproteins if they are sialylated. In this procedure, sialic acid residues were removed by mild acid hydrolysis and the desialylated glycoprotein was treated with anhydrous TFMSA reagent under conditions which remove all the carbohydrate residues except the core D-GalNAc linked to serine/threonine. The core D-GalNAc residues were removed by reacting the glycoprotein with periodate followed by a second treatment with anhydrous TFMSA; this procedure gave a completely deglycosylated protein. The protein thus obtained was soluble in aqueous buffers and useful for biochemical and biophysical studies. The method was successfully employed to isolate polypeptides from alpha 1-acid glycoprotein (N-linked), fetuin, canine tracheal mucin and gastric mucin.
Biochem Mol Biol Int 1994 Nov
PMID:New approach towards deglycosylation of sialoglycoproteins and mucins. 770 11

The hemocyanin of Rapana thomasiana grosse (marine snail, gastropod) is a glycoprotein with a carbohydrate content of 8.9% (w/w) and monosaccharide constituents xylose, fucose, 3-O-methylgalactose, mannose, galactose, N-acetylgalactosamine and N-acetylglucosamine residues. The two structural subunits of this oxygen carrier, RHSS1 and RHSS2, are unevenly glycosylated. On subtracting the carbohydrate contribution from the M(r) values of 250 and 450 kDa attributed to the two subunits, values of 2.18 x 10(5) daltons and 4.30 x 10(5) daltons were calculated for the polypeptide part of the "light" and "heavy" subunits, respectively. Comparison of the monosaccharide compositions of gastropodan hemocyanins revealed qualitative similarities, as well as relationships between the quantities, of the individual monosaccharides: Man > or = 3MeGal > GlcNAc > or = GalNAc and Fuc > or = Xyl.
Comp Biochem Physiol B Biochem Mol Biol 1995 Apr
PMID:Carbohydrate content and monosaccharide composition of Rapana thomasiana grosse (Gastropoda) hemocyanin and its structural subunits. Comparison with gastropodan hemocyanins. 774 26

Recent studies have extended our knowledge regarding the contents of mammalian cortical granules (CG) and their function in postfertilization events. Cytochemical staining has demonstrated the presence of carbohydrates within mammalian CG, and lectin-binding studies have shown that these carbohydrates include alpha-D-mannose, alpha-D-GalNAc, and galactose residues in the hamster, alpha-D-mannose in the mouse and cat, and beta-D-Gal(1,3)-D-GalNAc in the pig. Following fertilization and artificial activation, mannosylated material is released from CG and can be found on the oolemma and within the perivitelline space (PVS) of hamster oocytes. Fertilized or artificially activated rabbit, mouse, and human oocytes also release mannosylated, fucosylated and sialylated, and fucosylated material, respectively, which localizes to the oolemma. These glycosylated materials are probably of CG origin, although they have not been directly localized to the CG in rabbit, mice, and humans. The function(s) of the glycosylated material released from mammalian oocytes is not known, although it may participate in blocking polyspermy at the level of the plasma membrane, PVS, and/or zona pellucida (ZP), or it may facilitate preimplantation embryonic development. Proteinases, including tissue plasminogen activator, are also released from mammalian oocytes following fertilization and artificial activation, suggesting that they are of CG origin. These proteinases modify the ZP such that it is no longer receptive to sperm, and some proteinases have been suggested to bring about ZP hardening (an increased resistance to denaturing agents) by an unknown mechanism. Mouse ZP may also be hardened by an ovoperoxidase (cross-links tyrosine residues) cytochemically identified in mouse CG and CG exudate. The phenomena of ZP hardening in mammalian zygotes is not well understood but is likely to function in blocking polyspermic penetration of the ZP and/or in protecting embryos during preimplantation development. Recently, a 75 kD protein (p75) has been immunocytochemically localized to mouse CG and to the PVS of fertilized oocytes and two-cell embryos. The identity and function of p75 remains to be determined. Heparin binding placental protein may also be a CG component, since it is released from hamster oocytes following fertilization. It has not, however, been directly demonstrated to be a CG component, and its functions in fertilization and/or early embryonic development have yet to be defined.
Mol Reprod Dev 1994 Dec
PMID:Mammalian cortical granules: contents, fate, and function. 789 93

A 120 kDa glycoprotein in the larval midgut membrane of the lepidopteran Manduca sexta, previously identified as a putative receptor for Bacillus thuringiensis CrylA(c) delta-endotoxin, has been purified by a combination of protoxin affinity chromatography and anion exchange chromatography. In immunoblotting experiments, the purified glycoprotein has the characteristics predicted of the receptor: it binds CrylA(c) toxin in the presence of GlcNAc but not GalNAc; it binds the lectin SBA; but it does not bind CrylB toxin. N-terminal and internal amino acid sequences obtained from the protein show a high degree of similarity with the enzyme aminopeptidase N (EC 3.4.11.2). When assayed for aminopeptidase activity, purified receptor preparations were enriched 5.3-fold compared to M. sexta brush border membrane vesicles. We propose that the receptor for CrylA(c) toxin in the brush border membrane of the lepidopteran M. sexta is the metalloprotease aminopeptidase N.
Mol Microbiol 1994 Feb
PMID:The receptor for Bacillus thuringiensis CrylA(c) delta-endotoxin in the brush border membrane of the lepidopteran Manduca sexta is aminopeptidase N. 790 13

Pseudomonas aeruginosa employs pili to mediate adherence to epithelial cell surfaces. The pilus adhesin of P. aeruginosa strains PAK and PAO has been shown to bind to the glycolipid asialo-GM1 (Lee et al., 1994--accompanying article). PAK and PAO pili were examined for their abilities to bind to the synthetic beta GalNAc(1-4)beta Gal (a minimal structural carbohydrate receptor sequence of asialo-GM1 and asialo-GM2 proposed by Krivan et al., 1988a) using solid-phase binding assays. Both pili specifically bound to beta GalNAc(1-4)beta Gal. The binding of beta GalNAc(1-4)beta Gal-Biotin to the immobilized PAK and PAO pili was inhibited by corresponding free pili. The receptor binding domain of the PAK pilus resides in the C-terminal disulphide-looped region (residues 128-144) of the pilin structural subunit (Irvin et al., 1989). Biotinylated synthetic peptides corresponding the C-terminal residues 128-144 of P. aeruginosa PAK and PAO pilin molecules were shown to bind to the beta GalNAc(1-4)beta Gal-(bovine serum albumin (BSA)). The binding of biotinylated peptides to beta GalNAc(1-4)beta GAL-BSA was inhibited by PAK pili, Ac-KCTSDQDEQFIPKGCSK-OH (AcPAK(128-144)ox-OH) and Ac-ACKSTQDPMFTPKGCDN-OH (AcPAO(128-144)ox-OH) peptides. (In these peptides Ac denotes N alpha-acetylation of the N-terminus, -OH means a peptide with a free alpha-carboxyl group at the C-terminus and the 'ox' denotes the oxidation of the sulphhydryl groups of Cys-129 and Cys-142.) Both acetylated peptides were also able to inhibit the binding of beta GalNAc(1-4)beta Gal-biotin to the corresponding BSA-Peptide(128-144)ox-OH conjugates.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Microbiol 1994 Feb
PMID:The pili of Pseudomonas aeruginosa strains PAK and PAO bind specifically to the carbohydrate sequence beta GalNAc(1-4)beta Gal found in glycosphingolipids asialo-GM1 and asialo-GM2. 791 Sep 39


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>