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M N Fukuda

Publications and source records attributed to M N Fukuda.

81 records · Page 5Linked to original sources
PubMed1981

Anomalous cell surface structure of sickle cell anemia erythrocytes as demonstrated by cell surface labeling and endo-beta-galactosidase treatment.

Erythrocyte surface glycoproteins from patients with various types of sickle cell anemia have been analyzed and compared with those from normal individuals. By hemagglutination with various anti-carbohydrate antibodies, sickle cells showed profound increase of i antigens and moderate increase of GlcNAc beta 1 leads to 3Gal beta 1 leads to 3 Glc structure, whereas antigenicity toward globosidic structure was unchanged. In parallel to these findings, erythrocytes of sickle cell patients have additional sialylated lactosaminoglycan in Band 3. Thus, it can be concluded that erythrocytes of sickle cell patients are characterized by an altered cell surface structure which does not appear to be due to topographical changes of cell surface membrane. It is possible that the anemia or the "stress" hematopoiesis in these patients is responsible for these changes.

Anemia, Sickle Cell↗
PubMed1980

Membrane differentiation in human erythroid cells: unique profiles of cell surface glycoproteins expressed in erythroblasts in vitro from three ontogenic stages.

HUMAN ERYTHROBLASTS IN CULTURE, IRRESPECTIVE OF THE ONTOGENIC STAGE OF THEIR PROGENITORS, ARE CHARACTERIZED BY: (i) the barely detectable amount of band 3 glycoprotein, (ii) the presence of two glycoproteins with molecular weights 105,000 and 95,000, (iii) the high concentration of glycophorin, and (iv) a minimum quantity of the carbohydrate chain susceptible to endo-beta-galactosidase ("polylactosaminoglycan"). In contrast, mature erythrocytes, whether of fetal, neonatal, or adult origin, are characterized by a high concentration of band 3 glycoprotein, polylactosaminoglycan, and glycophorins, but do not contain 105- and 95-kilodalton-glycoproteins. Thus, the process of erythroid maturation from erythroblasts to erythrocytes is accompanied by the appearance of band 3, the disappearance of 105- and 95-kilodalton glycoproteins, and a great increase in the quantity of polylactosaminoglycan. The structure of polylactosaminoglycan may not be different between mature erythrocytes and erythroblasts from the same ontogenic stage, but it is distinctively different from one stage to the other. The profiles of oligosaccharides released by endo-beta-galactosidase and immunofluorescence studies with anti-Ii antibodies indicated that a linear polylactosaminoglycan structure was present in erythroblasts as well as in erythrocytes of the fetal and newborn stage, whereas a branched polylactosaminoglycan structure was present in erythroblasts as well as erythrocytes of adult blood. Thus, two membrane characteristics are closely associated with the process of erythroid cell development; one-the membrane proteins band 3, band 4.5, and 95- and 105-kilodalton glycoproteins-determines the degree of maturation, and the other-polylactosaminoglycan-may determine the ontogenic stage of the erythroblast progenitors.

Anion Exchange Protein 1, Erythrocyte↗
PubMed1980

Tk polyagglutination produced in vitro by an endo-beta-galactosidase.

After treatment with the culture supernatant of Bacteroides fragilis or with an endo-beta-galactosidase from Escherichia freundii, the human red blood cells are Tk-activated, i.e. agglutinable by BS II lectin and their blood group I and i activities are reduced. These results suggest that B. fragilis produces an endo-beta-galactosidase activity and that the main antigenic determinant of Tk polyagglutinable red cells is a terminal N-acetyl-glucosamine residue.

Agglutination↗
PubMed1979

Developmental change and genetic defect in the carbohydrate structure of band 3 glycoprotein of human erythrocyte membrane.

The chemical structure of Band 3 glycopeptide prepared from erythrocytes of normal adult (blood group OI), umbilical cord vessels (Oi), and an i adult variant who fails to develop I antigen (Oi), has been compared. Band 3 glycopeptide of cord erythrocytes gave, on permethylation analysis, predominantly 2,4,6-tri-O-methylgalactose and 3,6-di-O-methyl-2-N-methylacetamido-2-deoxyglucose, whereas the same glycopeptide of normal adult erythrocytes gave much higher amounts of 2,3,4,6-tetra-O-methylgalactose and 2,4-di-O-methylgalactose as compared with that of cord erythrocytes. Band 3 glycopeptide from i adult showed the same methylation pattern as cord-Band 3 glycopeptide. In accordance with these results, Band 3 glycopeptide of cord and i adult erythrocytes were hydrolyzed to mostly small oligosaccharides by endo-beta-galactosidase from Escherichia freundii, whereas that of normal adult produced a number of oligosaccharides with various sizes which was caused by branched structures. Based on these results and structures of released oligosaccharides, the major developmental change of carbohydrate structure in the erythrocyte membrane is the conversion of linear repeating Galbeta1 leads to 4GlcNAcbeta1 leads to 3Gal to a branched Galbeta 1 leads to 4GlcNAcbeta 1 leads to 3 (R leads to 6) Gal structure. i individual may result from the lack of the branching enzyme.

Carbohydrates↗
PubMed1976

Endo-beta-galactosidase of Escherichia freundii. Purification and endoglycosidic action on keratan sulfates, oligosaccharides, and blood group active glycoprotein.

Endo-beta-galactosidase was purified 4400-fold from a culture filtrate of Escherichia freundii with 45% recovery. The enzyme preparation was practically free of exoglycosidases, sulfatase, and proteases. This enzyme hydrolyzed several keratan sulfates, endoglycosidically releasing oligosaccharides of various molecular sizes. Among the digestion products of the corneal keratan sulfate, the structure of a disaccharride and a tetrasaccharride were shown to be 2-acetamido-2-deoxy-6-O-sulfo-beta-D-glucosyl-(1 leads to 3)-D-galactose and 2-acetamido-2-deoxy-6-O-sulfo-beta-D-glucosyl-(1 leads to 3)-6-O-sulfo-beta-D-galactosyl-(1 leads to 4)-2-acetamido-2-deoxy-6-O-sulfo-beta-D-glucosyl-(1 leads to 3)-D-galactose, respectively. These oligosaccharide structures indicate that this enzyme specifically hydrolyzes the galactosidic bonds in which nonsulfated galactose residues participate. The enzyme could also hydrolyze a small oligosaccharide such as lacto-N-neotetraitol as follows: Gal(beta 1 leads to 4)GlcNAc(beta 1 leads to 3)Gal(beta 1 leads to 4) sorbitol leads to Gal(beta 1 leads to 4)GlcNAc(beta 1 leads to 3)Gal + sorbitol AB active blood group substance could be hydrolyzed by this enzyme only after Smith degradation. After enzymatic digestion small oligosaccharides and resistant macromolecules were produced. These findings indicate that the enzyme should be useful in studying the precise structures of keratan sulfates, related glycoproteins, and oligosaccharides.

ABO Blood-Group System↗