Search PubMedSearch

Biomedical subjects

A M Wu

Publications and source records attributed to A M Wu.

At least 19 recordsLinked to original sources

Defining the carbohydrate specificities of Abrus precatorius agglutinin as T (Gal beta 1----3GalNAc) greater than I/II (Gal beta 1----3/4GlcNAc).

The combining site of the nontoxic carbohydrate binding protein (Abrus precatorius agglutinin, APA) purified from the needs of Abrus precatorius (Jequirity bean), was studied by quantitative precipitin and precipitin-inhibition assays. Of 26 glycoproteins and polysaccharides tested, all, except sialic acid-containing glycoproteins and desialized ovine salivary glycoproteins, reacted strongly with the lectin, and precipitated over 70% of the lectin added, indicating that APA has a broad range of affinity and recognizes (internal) Gal beta 1----sequences of carbohydrate chains. The strong reaction with desialized porcine and rat salivary glycoproteins as well as pneumococcus type XIV polysaccharide suggests that APA has affinity for one or more of the following carbohydrate sequences: Thomsen-Friedenreich (T, Gal beta 1----3GalNAc), blood group precursor type I and/or type II (Gal beta 1----3/4GlcNAc) disaccharide determinants of complex carbohydrates. Among the oligosaccharides tested, the T structure was the best inhibitor; it was 2.4 and 3.2 times more active than type II and type I sequences, respectively. The blood group I Ma-active trisaccharide, Gal beta 1----4GlcNAc beta 1----6Gal, was about as active as the corresponding disaccharide (II). From the above results, we conclude that the size of the combining site of the A. precatorius agglutinin is probably as large as a disaccharide and most strongly complementary to the Gal beta 1----3GalNAc (T determinant) sequence. The carbohydrate specificities of this lectin will be further investigated once the related oligosaccharide structures become available.

Binding, Competitive

Carbohydrate specificity of the receptor sites of mistletoe toxic lectin-I.

The carbohydrate specificity of mistletoe toxic lectin-I (ML-I) was studied by haemagglutination-inhibition assay. The results indicated that ML-I has a broad range of affinity for Gal alpha,beta linked sequences. The galabiose (E, Gal alpha 1----4Gal) sequence, a receptor of the uropathogenic E. coli ligand, was one of the best disaccharide inhibitors tested. The lectin also exhibits affinity for Lac(Gal beta 1----4Glc), T(Gal beta 1----3GalNAc), I/II(Gal beta 1----3/4GlcNAc) and B(Gal alpha 1----3Gal) sequences. Gal alpha 1----4Gal and Gal beta 1----4Glc are frequently occurring sequences of many glycosphingolipids located at the mammalian cell membranes, such as intestinal and red blood cell membranes, for ligand binding and toxin attachment. This finding provides important information concerning the possible mechanism of intoxication of cells by the mistletoe preparation.

Binding Sites

Reversal of the malignant phenotype by an anti-ras ribozyme.

In this study a ribozyme (catalytic RNA) was designed to site specifically cleave the mRNA of the activated H-ras gene expressed in human bladder carcinoma EJ cells. The optimal conditions for catalytic cleavage by the ribozyme were demonstrated in vitro. A synthetic DNA encoding the ribozyme was cloned into a mammalian expression vector (pH beta APr-1) and transfected into EJ cells. The expressed ribozyme significantly altered the morphology and suppressed the growth of EJ cells in vitro. These cell lines were examined for their malignant potential in athymic (nude) mice by an orthotopic (transurethral) implantation model, which recapitulates the invasive potential of various bladder carcinomas. EJ tumors expressing the H-ras ribozyme were characterized by a marked reduction in tumor take and invasion compared to those formed by control EJ cells. These differences resulted in almost a twofold increase in survival of mice implanted with ribozyme-containing EJ cells. These results further elucidate the role of ras genes in tumorigenicity and invasion, as well as introduce ribozymes as a new class of anticancer agents.

Animals

Immunochemical studies on the differential binding properties of two monoclonal antibodies reacting with Tn red cells.

Two monoclonal antibodies (MoAbs), BRIC 66 (IgM) and BRIC 111 (IgG1), were produced by immunizing mice with ovarian cyst blood group A1 glycoprotein and Tn red cells (RBCs), respectively. Their specificities were determined by inhibitions using Tn sialoglycoproteins (SGPs), mucins (armadillo [ASG] and ovine [OSG] submaxillary glycoproteins), and monosaccharides. BRIC 66 agglutinated both Tn and group A RBCs and reacted immunohistochemically with both the vascular endothelium and tumor cells from a group A adenocarcinoma, BRIC 66 was inhibited by N-acetylgalactosamine (GalNAc), Tn SGPs, and mucins on both hemagglutination inhibition tests and radioimmunoassay. BRIC 111 agglutinated Tn RBCs only, and it specifically stained tumor cells from a group O patient's breast carcinoma and a group A patient's adenocarcinoma. In hemagglutination inhibition tests, BRIC 111 was readily inhibited by Tn SGPs, only partially inhibited by GalNAc, and not inhibited by mucins. In a sensitive radioimmunoassay, BRIC 111 was inhibitable by GalNAc. Tn SGP was 2000-fold more effective as an inhibitor than the mucins (ASG and desialized OSG), which contain a high content of terminal alpha-GalNAc-O-serine (threonine) residues. It is postulated that BRIC 66 is specific for terminal alpha-GalNAc units in carbohydrate chains. The exclusive reaction of BRIC 111 with Tn SGP indicates a combining site larger than GalNAc alpha-1, which probably includes amino acid residues in juxtaposition to GalNAc in Tn SGP. In view of its specific agglutination of Tn RBCs, BRIC 111 is a useful reagent for the examination of polyagglutinable RBCs.

ABO Blood-Group System

Genotype and phenotype: a practical approach to the immunogenetic analysis of lymphoproliferative disorders.

Determination of cell lineage and clonality in lymphoproliferative disorders (LPD) is greatly enhanced by molecular genetic analysis in conjunction with morphologic and immunologic techniques. We now report on a technique in which we used cryostat-cut, fresh-frozen sections (CCFFS) prepared from tissues in a manner that allows DNA hybridization studies to be coordinated readily with routine morphologic and immunohistologic studies. Thirty-seven cases representing a broad spectrum of reactive and malignant LPD were examined with this method. Samples of DNA were extracted from frozen sections, subjected to Southern blot hybridization, and probed for rearrangements of the immunoglobulin (Ig) heavy-chain and the kappa and lambda light-chain genes, as well as for the T-cell receptor beta-chain gene. We also evaluated the effects of (1) diagnostic category of LPD, (2) volume of the tissue sample, and (3) fibrosis, necrosis, and ice crystal artifacts in the sample on the recovery of DNA. Ice artifact and sample size had the greatest negative impacts on the quantity and condition of DNA recovered. Of 19 samples involved by B-cell LPD, the results of immunogenetic studies were consistent with the immunophenotypes in all but one case. Of the T-cell lymphomas from which sufficient DNA was available (three out of five of the T-cell cases), all showed rearrangements of the T-cell beta-chain gene. In order to reduce sample processing time, we evaluated alternate blot hybridization methods, rapid alkaline transfers, and direct hybridization of synthetic oligonucleotides in dried agarose gels, and found that they decreased the time required for hybridization studies. In summary, the use of CCFFS as the source of DNA allows study of gene rearrangements and, at the same time, preserves frozen-tissue blocks in tumor banks for further immunologic studies. The development of time-effective methods will make the routine use of molecular-genetic analysis more practical in the diagnostic hematopathology laboratory.

Culture Techniques

Immunogenicity of subcellular fractions of Brucella abortus: measurement by in vitro lymphocyte proliferative responses.

Five groups of heifers were immunized with various subcellular fractions of Brucella abortus and tested for their responsiveness in lymphocyte proliferative responses in vitro. The five subcellular fractions used as immunogens were: (1) a mixture of recombinant outer membrane proteins fused to Escherichia coli beta-galactosidase, (2) a mixture of outer membrane proteins BaomI, BaomIIB1, and BaomIII1, (3) a mixture of outer membrane proteins 7.5 kDa and 8.8 kDa, (4) a complex of smooth lipopolysaccharide and proteins, and (5) a complex of outer membranes and peptidoglycan (OM-PG complex) from a rough strain. All immunogens were emulsified in adjuvant and administered twice at a 61-day interval. Two other groups of cows were included; one immunized with strain 19 and the other with adjuvant only. Strain 19 and the rough OM-PG complex induced responsiveness in lymphocyte proliferation assays in a high percentage of immunized cows. The smooth lipopolysaccharide-protein complex induced responsiveness in fewer cows. The lowest frequencies of responding cows were found in groups that received either recombinant proteins or purified protein mixtures. Based on these results, we concluded: (1) cellular immunity, as measured by in vitro lymphocyte proliferative responses, can be induced with subcellular fractions of B. abortus and (2) the more complex the immunogen, the greater the frequency of responding cows.

Analysis of Variance

Analysis of antigen receptor gene rearrangements in ethanol and formaldehyde-fixed, paraffin-embedded specimens.

Molecular hybridization analysis of DNA prepared from frozen specimens obtained from patients with lymphoproliferative disorders has aided in the determination of the lineage and clonality of the neoplastic cells in many cases. We investigated whether high molecular weight DNA suitable for nucleic acid hybridization studies could also be prepared from fixed, paraffin-embedded material. After selecting nine representative cases, we extracted DNA from frozen sections by using standard methods, and from ethanol-fixed tissue in paraffin blocks. The yields of DNA from ethanol-fixed blocks were similar to yields from frozen tissue. DNA from frozen and ethanol-fixed tissues was subjected to Southern blot hybridization and probed for rearrangements of immunoglobulin heavy, and kappa, and lambda light chain genes, as well as for the T cell receptor beta-chain gene. In each of the cases, comparable results were obtained, regardless of the source of DNA. DNA extracted from ethanol-fixed blocks stored for 2 years gave identical results. We also prepared DNA from formaldehyde-fixed, paraffin-embedded tissue obtained from six of the patients. Five of the specimens yielded spoolable DNA (average recovered, 313 micrograms), but the DNA was degraded more than that obtained from the frozen or ethanol-fixed specimens. Formaldehyde-treated DNA gave variable results in Southern blot hybridization studies, and less than half of the results were interpretable. We conclude that ethanol-fixed, paraffin-embedded tissues provide an excellent source of DNA for nucleic-acid hybridization studies, and that they are easily handled and stored.

DNA

Monocytoid B-cell lymphoma: its evolution and relationship to other low-grade B-cell neoplasms.

Monocytoid B-cell lymphoma (MBCL) is a newly recognized B-cell neoplasm of uncertain histogenesis. The cytologic features of the neoplastic monocytoid B lymphocytes are virtually identical to those of hairy cell leukemia (HCL). As with HCL, progression of MBCL to a higher histologic grade is very unusual. However, whereas circulating leukemic cells are a characteristic feature of HCL, peripheral blood involvement has not been reported in MBCL. We recently studied a patient with MBCL of the spleen and axillary lymph nodes who developed peripheral blood involvement by MBCL cells. Unlike the cells of HCL, the circulating MBCL cells exhibited strong acid phosphatase activity that was tartrate sensitive. The leukemic cells had the antigenic phenotype IgM lambda, CD20+, CD11c+, CD5-, CD25(TAC)-, and PCA-1-. Immunogenetic studies of both lymph node and peripheral blood cells revealed identical immunoglobulin heavy-chain gene rearrangements. When compared with a series of HCL, the immunophenotype was similar except for the absence of PCA-1 and TAC. Progression of the MBCL to a large cell lymphoma, also expressing IgM lambda, was documented in an abdominal lymph node of this patient. Therefore, although rare, peripheral blood involvement by lymphoma cells may occur during the course of MBCL and should be distinguished from HCL with cytochemical and immunophenotypic studies. In addition, comparison of the clinical, pathologic, and immunologic features of MBCL with those of other low-grade B-cell neoplasms suggests that a close lineage relationship exists between MBCL and HCL.

Adult

Immunochemical studies on the N-acetyllactosamine beta-(1----6)-linked trisaccharide specificity of Ricinus communis agglutinin.

The combining site of Ricinus communis agglutinin (RCA1) was studied by quantitative precipitin and precipitin inhibition assays. Of 31 complex carbohydrates tested, all except active and inactive antifreeze glycoproteins, Streptococcus group C polysaccharide, and native rat salivary glycoprotein, reacted strongly, and 22 completely precipitated the lectin, indicating that RCA1 has both a broad range of affinity and a low solubility of its carbohydrate-bound complex. Of the monosaccharides and glycosides tested for inhibition of precipitation, p-nitrophenyl beta-D-galactopyranoside was the best. It was about 6.4 times better than methyl beta-D-galactopyranoside. The beta anomer of glycosides of D-galactose was much more potent than the corresponding alpha anomer. Among the oligosaccharides tested, beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)-D-Gal was the best inhibitor, which was approximately 2/3 as active as p-nitrophenyl beta-D-galactopyranoside. It was approximately 1.4 times as active as beta-D-Gal-(1----4)-D-GlcNAc (N-acetyllactosamine), twice as active as beta-D-Gal-(1----3)-D-GlcNAc, and 4.5 times more active than lacto-N-tetraose. From the results, it can be concluded that; (a) hydrophobic interaction is important for binding; (b) the combining site of this lectin is at least as large as a trisaccharide; and (c) of the compounds studied, the trisaccharide beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)-D-Gal was the most complementary to the human blood group I Ma determinant beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)-D-Gal.

Amino Sugars

Structural concepts of the human blood group A, B, H, Le(a), Le(b), I and i active glycoproteins purified from human ovarian cyst fluid.

Regardless of the A, B, H, Le(a), Le(b), I and i activity, purified water-soluble blood group glycoproteins from human ovarian cyst fluid have a similar overall structure. They are polydisperse macromolecules (Mr 2.0 x 10(5) to several million) of similar composition (75 to 85% carbohydrate, 15 to 20% protein) and consist of multiple heterosaccharide side chains attached by an O-glycosidic linkage at their internal reducing ends to serine or threonine of the polypeptide backbone. About 90% of these carbohydrate side chains range in size from one to less than twenty-four sugar residues (twelve sugars in the internal structure and twelve key sugars specific as blood group determinants). Three-fourths of these side chains contain fewer than twelve sugars. A generalized blood group active carbohydrate chain is shown above. Three disaccharide units-Type I chain (Gal beta 1----3GlcNAc beta 1----3), Type II chain (Gal beta 1----4GlcNAc beta 1----6) and T determinant [Gal beta 1----3GalNAc alpha 1----Ser(Thr)]-are used to elucidate the internal structure of the carbohydrate chains. The complete internal structure is considered to have a core structure with four branches, to which the blood group key sugars are attached at the appropriate locations. The core structure is a tetrasaccharide, composed of one unit of Type I chain at the nonreducing end and the T determinant at the other end, linked to Ser or Thr of the protein moiety. Branch I is Type I chain and Branch II is Type II chain. They are linked to Gal at the nonreducing end of the core structure. Branch III is usually a Type II chain, but may sometimes be a Type I chain, linked to the GalNAc of the reducing end. The length of Branch III can be increased by adding one or more monosaccharides of Type I chain sequence such as Gal beta 1----3GlcNAc beta 1----3Gal beta 1----4GlcNAc beta 1----6GalNAc alpha 1----Ser(Thr), a combination of Type I and Type II chains. A new Branch IV is made up of Type II chain, which in turn is linked to the Gal end of the T determinant. The Type II chains react with the antibody to the type XIV pneumococcal capsular polysaccharide and with the anti-I(Ma) cold agglutinin.(ABSTRACT TRUNCATED AT 400 WORDS)

Blood Group Antigens

Biochemistry and lectin binding properties of mammalian salivary mucous glycoproteins.

The molecules responsible for the highly viscous properties of mucus are secretory glycoproteins referred to as mucins. Salivary mucins are characterized by a high sugar to protein ratio and are of a broad range of molecular weight from 7 x 10(4) to millions. With a few exceptions, they contain up to 30% of hexosamine (galactosamine and glucosamine), 8-33% of sialic acid, trace to 15% of galactose or fucose and little or no mannose. The size of carbohydrate side chains of these glycoproteins ranges from one to about fifteen units of sugar. These carbohydrate side chains are usually O-glycosidically linked through N-acetylgalactosamine to a peptidyl serine or threonine. In some instances, ester sulfate groups, mainly on N-acetylglucosamine, are also a structural feature. In many of these glycoproteins, the saccharide sequence is the same as that which determines the specificity of blood groups. Carbohydrate sequence analysis shows that salivary mucins exhibit considerable polydispersity, great diversity and remarkable structural flexibility not only among animal species but also within the same mucin molecule. Based on their lectin-binding ability, they can be used for purification of lectins, and lectins coupled to resin may be useful for the isolation of mucin-type glycoproteins. The epithelial mucous secretions modulate oral microbial flora; many secretory components serve as lectin-receptors for the attachment of microbes. The judicious use of lectins with widely differing binding characteristics has already been valuable in the in situ localization of salivary glycoproteins, in elucidating structural details, recording sugar density within a given tissue section, and defining host-parasite interactions. It is hoped that their use, together with monoclonal antibody (158) and tissue culture techniques (159, 160) will further clarify the roles of individual secretory mucous glycoproteins in health and disease.

Animals

Structural and immunochemical aspects of Brucella abortus endotoxins.

Smooth lipopolysaccharide (sLPS) of Brucella abortus, which is the most immunodominant component among the antigens of B. abortus isolated, has been used for diagnosis for decades. High yields of sLPS can be prepared by a modification of the procedures of Moreno et al. (J. Bacteriol. 138:361-369, 1979). Washed B. abortus cells can be disrupted by 21 freeze-quick thaw cycles and ultrasonication to separate non-membrane-bound material; then phenol extraction is performed 3 times and the phenol fraction is washed with H2O intensively. The membrane-bound sLPS can be fractionated into 3 to 5 groups according to the extent of dialysis and centrifugation. These membrane bound sLPS fractions show marked individual differences in their precipitin profile and chemical composition. Their protein content varies from 16% to 42% as determined by dye binding test and 17 to 60% by Lowry phenol method using bovine serum albumin as the standard, which indicates that these proteins associated with LPS may play important roles in the immunochemical interactions, solubility, and the heterogeneity of B. abortus lipopolysaccharides. Compared to previously published methods, a higher yield of sLPS, ranging from 3.6% to 7.7% of dried bacteria, is obtained. Group f5A, which has a standard bell shaped curve in the precipitin assay, is one of the major fractions in all three strains (1119.3, 19, 2308). The protein free sLPS (less than 1% of Lowry reactive component) can be prepared by pronase digestion. The immunochemical reactivity remains about the same before and after this treatment. The O-chains of the major fraction (f5A) of B. abortus (Strains 2308 and 19) membrane bound smooth lipopolysaccharide (sLPS) are obtained by hydrolysis of f5A native sLPS in 1% acetic acid at 100 degrees C for 2 hours. After hydrolysis, the O-chains are separated from the lipid A protein complex by centrifugation, and from small fragments by ultrafiltration of a molecular weight cut-off (MWCO) of 1.0 x 10(3). These carbohydrate haptens can be identified by precipitin-inhibition assay and further fractionated by both membrane filtration and dialysis. The size distributions of carbohydrate haptens of the endotoxins (f5A) ranged from several oligosaccharides up to 1.0 x 10(4) MWCO. Three major fractions of MWCO 8.0-10.0 x 10(3), 3.5-5.0 x 10(3), and less than 1.0 x 10(3) for both strains 2308 and 19 contain more than 85% of the total immunreactive materials.(ABSTRACT TRUNCATED AT 400 WORDS)

Brucella abortus

Differential binding properties of Ga1NAc and/or Ga1 specific lectins.

Grouping of lectin binding properties, based on determinant structure rather than monosaccharide inhibition pattern, should facilitate the selection of lectins as structural probes for glycans as well as for the interpretation of the distribution and the properties of the carbohydrate chains on the cell surface. Based on the binding specificities studied with glycan by precipitin-inhibition, competitive-binding and hemagglutinin-inhibition assays, twenty Ga1 and/or Ga1NAc specific lectins have been divided into six classes according to their specificity for the disaccharide as all or part of the determinants and Ga1NAc alpha 1----Ser(Thr) of the peptide chain. The differential affinities of these lectins were characterized by quantitative precipitin assay. Abbreviation of the following six lectin determinants can also be used to classify these lectins. (1) F determinant (GalNAc alpha 1----3GalNAc, Forssman specific disaccharide). (2) A (Af) determinant (GalNAc alpha 1----3Gal, Human blood group A specific disaccharide; Af, fucosylated A, (GalNAc alpha 1----3 [LFuc alpha 1----2]Gal). (3) Tn determinant (GalNAc alpha 1----0 to Ser (Thr) of the protein core, Tn antigen). (4) T determinant (T antigen, Gal beta 1----3GalNAc alpha 1----0 to Ser (Thr) of the protein core, the mucin type sugar sequence on the human erythrocyte membrane or Gal beta 1----3GalNAc beta 1---- at the nonreducing end of ganglioside). (5) I and II determinants (human blood group type I and II carbohydrate sequences). Most of the lectins reactive to Gal beta 1----4GlcNAc (II) are also reactive to Gal beta 1----3GlcNAc (I). Lectin I (II) determinants (i.e. Gal beta 1----3 (4) GlcNAc residues) can be found at the nonreducing end of the carbohydrate chains derived from either N-glycosidic or O-glycosidic linkages. (6) B determinant (Gal alpha 1----3Gal, Human blood group B specific disaccharide). Their carbohydrate specificities are classified as following: (Table see text). The differential binding properties of lectins can be defined from comparisons of their carbohydrate specificities listed above.

Acetylgalactosamine

Immunochemical and partial chemical characterization of fractions of membrane-bound smooth lipopolysaccharide-protein complex from Brucella abortus.

Smooth lipopolysaccharide (sLPS) of Brucella abortus was prepared and fractionated by a modification of the procedures of Moreno et al. (J. Bac. 138:361-369, 1979). Washed B. abortus cells were disrupted by 21 freeze-quick thaw cycles with ultrasonication to separate the non-membrane-bound material. Ultrasonicated bacteria were used for preparation of membrane-bound sLPS (approximately f5, the main crude sLPS fraction described by Moreno et al.). Phenol extraction was repeated 3 times and then washed with H2O 10 times to remove most of the chromogen, polysaccharides and nucleic acids, eliminating the need for enzyme treatment as described previously. The membrane-bound sLPS was fractionated into 3 to 5 groups according to the extent of dialysis and centrifugation, these fractions required only 80 ng for positive ELISA, about 0.2 ng for positive Limulus lysate tests, and reacted well with precipitating antibodies in the serum from a strain 2308 infected cow. They had marked differences in precipitin curves and chemical composition. The protein content varied from 16% to 42% as determined by dye binding test and 17 to 60% by Lowry phenol method using bovine serum albumin as the standard, which implies that the proteins associated with LPS may also play important roles in the complex for the immunochemical interactions and the heterogeneity of B. abortus lipopolysaccharide protein complex. As compared with previous reports, a higher yield of sLPS, ranging from 3.6% to 7.7% of dried bacteria, was obtained. Group f5A, which had a standard bell shaped curve in the precipitin assay, is one of the major fractions in all three strains (1119.3, 19 and 2308). The amount of other subfractions obtained varied with batches or strains of B. abortus. These results provide a new profile of the immunochemical reactivities and the heterogeneity on B. abortus smooth membrane-bound endotoxins.

Antigen-Antibody Complex

Structural and immunochemical characterization of the O-haptens of Brucella abortus lipopolysaccharides from strains 19 and 2308.

The O-haptens of the major fraction (f5A) of B. abortus (Strains 2308 and 19) membrane bound smooth lipopolysaccharide (sLPS) were prepared by hydrolysis of f5A native sLPS in 1% acetic acid at 100 degrees C for 2 h. After hydrolysis, O-haptens were separated from Lipid A-protein complex by centrifugation, and from small fragments by ultrafiltration of molecular weight cut-off (MWCO) 1.0 X 10(3). These carbohydrate haptens were identified by precipitin-inhibition assay and further fractionated by both membrane filtration and dialysis. The size distributions of carbohydrate haptens of endotoxins (f5A) ranged from oligosaccharides up to polysacchandes of 1.0 X 10(4) MWCO. Three major fractions of MWCO 8.0-10.0 X 10(3), 3.5-5.0 X 10(3) and less than 1.0 X 10(3) from both strains 2308 and 19 contained more than 85% of the total immunoactive materials. These fractions of haptens were subjected to composition, proton and 13C NMR analysis and were found to be a homopolymer of alpha 1----2 linked, 4,5-dideoxy-4-formamido-D-mannose (N-formylperosamine), which is identical to O-haptens of B. abortus strain 119.3 and Yersinia enterocolitica serotype 0:9 and similar to Vibrio cholerae 569B (INABA). Fractions of these haptens exhibited similar inhibitory reactivities in a precipitin-inhibition assay as expressed as mumoles of monosaccharide of anhydro-N-formyl perosamine. They were about 480 times as active as Me alpha----DMan or DMan.

Brucella abortus

Typing of core and backbone domains of mucin-type oligosaccharides from human ovarian-cyst glycoproteins by 500-MHz 1H-NMR spectroscopy.

Human blood-group A active glycoproteins from ovarian-cyst fluid were subjected to Smith degradation and subsequent beta-elimination. The resulting oligosaccharide-alditols represent the core and backbone domains of the O-linked carbohydrate chains. Nine of these, ranging in size from disaccharides to hexasaccharides, were investigated by 1H-NMR spectroscopy. Their primary structures could be adequately characterized. In particular, the core types, i.e. the substitution patterns of N-acetylgalactosaminitol (GalNAc-ol) as well as the types of backbone, i.e. the linkage types of alternating Gal-GlcNAc sequences, were unambiguously identified. The core type GlcNAc beta(1-3)GalNAc-ol is described for the first time as occurring in ovarian-cyst glycoprotein.

ABO Blood-Group System