Arne Lundblad

Two urinary oligosaccharides characteristics of A1 and B secretors: Isolation and partial characterization

Abstract Two blood-group specific oligosaccharides have been isolated from urine of human A 1 and B secretors. Their chemical composition and behavior in gel chromatography and paper chromatography indicate pentasaccharide structures, the oligosaccharide from A 1 secretors being composed of fucose:glucose:galactose: N -acetyl-galactosamine (2:1:1:1) and the oligosaccharide from B secretors of fucose : glucose : galactose (2:1:2). Glucose was demonstrated to be the reducing end-group in both. Serological tests showed inhibition by the A 1 oligosaccharide in the A 1 anti-A system and by the B oligosaccharide in the B anti-B and O anti-H systems.

Isolation and characterization of a urinary oligosaccharide characteristic of blood group O(H)-secretors.

Abstract A blood group-characteristics obligosaccharide has been isolated from urine of human group O(H)-secretors. Its chemical composition and behaviour in paper chromatography strongly indicate that it is identical with lactodifucotetraose. Both substances have glucose in the reducing end group, and seem to give the same degradation products on partial acid hydrolysis. Lactodifucotetraose has previously been found only in pregnant and lactating women.

The relationship between different forms of human alpha-mannosidase

The tissue distribution and some properties of human alpha-mannosidase (alpha-D-mannoside mannohydrolase EC 3.2.1.24) have been studied. The acidic forms of the enzyme were fairly stable, whereas the neutral forms easily lost enzymic activity. The acidic forms were sensitive to neuraminidase but the neutral forms were unaffected. The experiments indicate that the acidic components are closely related to each other, differing only in sialic acid content and possibly conformation. The neutral forms of the enzyme are probably quite different from the acidic forms both in structure and cellular function.

Mannosidosis: Detection of the disease and of heterozygotes using serum and leucocytes

Abstract α-D-mannosidase activity in serum and leucocytes from normal individuals, patients with mannosidosis and their parents was measured at pH 4.4 and pH 6.0. When the results were expressed as total activity or specific activity at pH 4.4 in both tissues, or as a ratio of enzyme activity at the two pH conditions in serum, the disease could be diagnosed, but the heterozygotes could not be distinguished from the controls. However, all three groups could be recognised when acid α-mannosidase activity was related to total activity in serum and leucocytes. The distribution of α-mannosidases, as separated by ion-exchange chromatography was different in each tissue. The serum profile was unique, all components having substantial “neutral” activities which are unaltered in mannosidosis and carriers.

Excretion of oligosaccharides in the urine of secretors and non-secretors belonging to different blood groups

Abstract 1. 1. It was confirmed that secretors of blood-group substances have a higher urinary excretion of fucose than non-secretors. The difference was found to be more pronounced in non-starved individuals than in individuals who had starved for 12 h. 2. 2. Gel filtration of urinary ultrafiltrates of starved secretors revealed fucose patterns characteristic of each blood group, whereas non-secretors displayed the same pattern, irrespective of blood group. 3. 3. The fractions accounting for the main difference between the gel-filtration patterns of A1 and B secretors were further separated by paper chromatography. One main spot was found in each type, with a mobility characteristic of the blood group. Another gel-filtration fraction, characteristic of O secretors, showed three main spots not present in the corresponding fraction from A1, B or non-secretors.

Structure of two urinary oligosaccharides characteristic of blood group O(H)- and B-secretors

Abstract The structures of two blood group-specific oligosaccharides isolated from urine of human O(H)- and B-secretors have been investigated essentially by methylation analysis of the original oligosaccharides and of partially hydrolysed products. Structures of the oligosaccharides are presented as a result of these studies. The oligosaccharide characteristic of O(H)-secretors is identical with lactodifucotetraose. The B-secretor oligosaccharide is composed of galactose linked α (1 → 3) to the galactose in lactodifucotetraose.

Gel filtration of the low molecular weight carbohydrate components of normal urine

Abstract The ultrafilterable material of normal human male urine was fractionated by gel filtration on Sephadex G-25 fine (250–400 mesh). At least 6 reproducible anthrone-reacting carbohydrate fractions were obtained. All of them appeared to contain methylpentose and at least five of them seemed to contain uronic acid. The ninhydrin-reacting material showed at least two peaks. Hexosamine analyses have also given at least two maxima.

Mannosidosis in angus cattle: Partial characterization of two mannose containing oligosaccharides

In 1957 Whittem and Walker described a lethal nervous disease of Angus cattle that microscopically resembled the human lipidoses [1 ]. Being unable to demonstrate lipid within vacuolated neurones they referred to the condition as neuronopathy and pseudolipidosis. More recently it has been demonstrated that an oligosaccharide containing three mannose and one glucosamine residue could be isolated from lymph nodes of affected calves, but not from normal animals, and that affected calves had a severe deficiency of a-mannosidase in tissues [2]. The disease was inherited as an autosomal recessive and heterozygotes were shown to have less than half the normal level of ~t-mannosidase in plasma. This bovine condition was thus shown to be similar to human mannosidosis which is also associated with a deficiency of,v-mannosidase and accumulation of mannose containing oligosaccharides [3, 4] in tissues. The term mannosidosis of Angus cattle was suggested as being preferable to the name pseudolipidoses [2]. The purpose of the present investigation was to study the stored material in calf brain and the urinary exretion of mannose containing oligosaccharides. Two oligosaccharides were isolated from the calf brains. Chromatographic behavior and sugar analysis suggest that both are tetrasaccharides with two D-mannose and two N-acetyl-D-glucosamine residues. Neither of these tetrasaccharides are identical with oligosaccharides isolated from urines of human patients with mannosidosis.

Isolation of fucose-rich glycopeptides from normal urine

Abstract The non-ultrafilterable material from pooled human urine was submitted to block electrophoresis and two fractions relatively rich in fucose but poor in other sugars and in proteins were further fractionated by various means. The material proved to contain a considerable number of fucose-rich glycopeptides, some of which were obtained in a reasonably pure state. The molecular weight was determined in three instances, giving values in the range of 5 000–10 000. Two of the glycopeptides were chemically characterized. One of them had a chemical composition very close to that given for purified blood group antigens. It was serologically inactive.

Isolation and characterization of urinary A and B agglutinogen fractions

Abstract Urinary A and B agglutinogen fractions with high serological activity have been isolated. The presence of glucose was demonstrated in both fractions. In other respects, the chemical composition of A substance material was compatible with a glycoprotein structure similar to that of soluble blood group antigens.