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J C Michalski

Publications and source records attributed to J C Michalski.

At least 91 records · Page 5Linked to original sources
PubMed1982

The structures of six urinary oligosaccharides that are characteristic for a patient with Morquio syndrome type B.

Morquio syndrome type B is an inherited, lysosomal storage disease characterised by a marked deficiency in acid beta-D-galactosidase, while the 2-acetamido-2-deoxy-beta-D-galactose 6-sulphate sulphatase activity is normal. Urinary oligosaccharides were studied in order to evaluate the effect of the diminished beta-D-galactosidase activity on the catabolism of glycoconjugates and to compare their structure with those excreted by patients with GM1-gangliosidosis. The following oligosaccharides were isolated: beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 6)-beta-D-Manp-(1 leads to 4)-D-GlcpNac(1), beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 6)-[alpha-D-Manp-(1 leads to 3)]-beta-D-Manp-(1 leads to 4)-D-GlcpNAc (2a), beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 3)-[alpha-D-Manp-(1 leads to 6)]-beta-D-Manp-(1 leads to 4)-D-GlcpNAc (2b), beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 3)-[beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 6)]-beta-D-Manp-(1 leads to 4)-D-GlcpNAc (3), beta-D-Galp-(1 leads to 4)-beta-D-Glcp-NAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 3)-(beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-[beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 6)]-alpha-D-Manp-(1 leads to 6))-beta-D-Manp-(1 leads to 4)-D-GlcpNAc (4), beta-D-Galp-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 3)-[beta-D-GlcpNAc-(1 leads to 4)]-[beta-D-Glap-(1 leads to 4)-beta-D-GlcpNAc-(1 leads to 2)-alpha-D-Manp-(1 leads to 6)]-beta-D-Manp-(1 leads to 4)-D-Glcp-NAc (5). Significant differences between Morquio syndrome type B and GM1- gangliosidosis have been observed, with regard to the excretion rate and the specific structures of urinary oligosaccharides. Compounds 2a, 2b, and 5 are novel members of the series of oligosaccharides isolated from the urine of patients with inherited lysosomal storage diseases.

Carbohydrate Conformation↗
PubMed1982

Solubilization and affinity chromatography of a sialidase from human liver.

A sialidase, acting on gangliosides and mucus glycoproteins (pH optimum 4.0-4.5) was solubilized by 1% Triton X-100 and short ultrasonication from a crude mitochondrial-lysosomal fraction isolated from human liver. The enzyme was enriched over 1000-fold with the aid of affinity chromatography on equine submandibular gland mucin bound to Sepharose and 20mM Tris/HCl buffer, pH 7.5, as eluent. The sialidase exhibited a molecular mass of about 200 000 Da on Sephadex G-200. On analytical gel electrophoresis, an enzymically active protein band of about 70 000 Da was observed. A sialidase acting on sialyllactose remained in the membrane fraction and could not be solubilized.

Chromatography, Affinity↗
PubMed1981

New chromatographic system for the rapid analysis and preparation of colostrum sialyloligosaccharides.

A new thin-layer chromatographic system on silica gel for the separation of sialyloligosaccharides is described. Calibration of the system with standard milk and colostrum sialyloligosaccharides is presented. The use of the system in monitoring different oligosaccharides is demonstrated for the purification of bovine colostrum sialyllactose isomers and a commercial sialyllactose product, and is discussed with respect to other biological fluids. The large-scale preparation of pure sialyllactose isomers from bovine colostrum is achieved using an improved ion-exchange separation on Dowex 1-X2 (less than 400 mesh) employing isomolar elution at 20 mM for monosialyloligosaccharides and 200 mM for disialyllactose. The purification of four major monosialyltrisaccharides, the 2-3 and 2-6 isomers of N-acetylneuraminyllactose, N-glycolylneuraminyl2-3lactose and N-acetylneuraminyl2-6-N-acetyllactosamine, and the disialyltetrasaccharide di-N-acetylneuraminyllactose is reported. The detection and partial purification of three new minor monosialyloligosaccharides is described.

Animals↗
PubMed1981

The release of N-acetyl- and N-glycolloyl-neuraminic acid from soluble complex carbohydrates and erythrocytes by bacterial, viral and mammalian sialidases.

A series of substrates, sialyl(2 leads to 6)GalNAc and ganglioside GM3, containing either N-acetylneuraminic acid (AcNeu) or N-glycolloylneuraminic acid (GcNeu), has been prepared. The trisaccharide GcNeu(2 leads to 3)lactose was preapred by ozonolysis of GcNeu-GM3, and the disaccharides AcNeu(2 leads to 6)GalNAc and GcNeu(2 leads to 6)GalNAc were isolated from bovine submandibular-gland mucin by alkali elimination. Sialidases from Newcastle-disease virus, fowl-plague virus, influenza virus A2, Clostridium perfringens, Vibrio cholerae, Arthrobacter ureafaciens and human liver lysosomes were studied with the above substrates and all showed poorer cleavage of GcNeu-containing substrates when compared with the corresponding AcNeu-containing compounds. This was reflected in the Km and Vmax. values of these sialidases. Differences between viral and bacterial sialidases could be detected on the basis of their kinetic constants and time curves of sialic acid release. Preferred release of AcNeu relative to GcNeu was also observed with bovine submandibular gland mucin and a mixture of human and porcine erythrocytes, macromolecular substrates containing both AcNeu and GcNeu. The significance of differential cleavage of AcNeu and GcNeu by sialidases is considered together with examples of the role of GcNeu in physiologicaL systems.

Animals↗
PubMed1980

Horse erythrocyte gangliosides: preparation of the major hematoside NeuNG1-Lac-Cer.

A simple method for the isolation of hematoside NeuNG1-Lac-Cer from horse erythrocytes is described. An aliquot of the crude ganglioside fraction was labeled by tritiated sodium borohydride after mild periodate oxidation. The compounds obtained were used as radioactive tracers in column chromatography. Gangliosides were applied onto a silicic acid column and eluted stepwise by solvents of steadily increasing polarity. The major ganglioside, NeuNG1-Lac-Cer, was eluted in a high yield by the solvent mixture chloroform/methanol/water (60:35:8, v/v/v).

Animals↗
PubMed1980

Macular cherry-red spot and myoclonus syndrome. Juvenile form of sialidosis.

Macular cherry-red spot, myoclonus and progressive mental deterioration are described in a man of 16 years. Morphological examination of the liver, bone marrow and fibroblasts showed numerous vacuoles containing storage material in the cytoplasm of the cells. Twelve different oligosaccharides were isolated from urine and their structures were determined. All have N-acetylglucosamine in a reducing end and (2--3) and 2--6) neuraminic acid in the terminal position. This abnormal urinary oligosaccharide excretion is due to absence of (2--6) neuraminidase which was not detected in fibroblast culture. This case is discussed in relationship to other cases with macular cherry-red spot, myoclonus and oligosaccharide urinary excretion.

Adolescent↗
PubMed1979

Sialidosis, a new type of inborn disease.

We describe the biochemical findings concerning five different types of mucolipidosis which have been defined as sialidosis on the basis of the specific enzyme deficiency and the nature of the storage material.

Adolescent↗
PubMed1978

360-MHz 1H nuclear-magnetic-resonance spectroscopy of sialyl-oligosaccharides from patients with sialidosis (mucolipidosis I and II).

360-MHz proton nuclear magnetic resonance spectra were recorded of 10 sialyl-oligosaccharides isolated from urine of sialidosis patients. Their structures are related to the complex asparagine-linked glycan chains of glycoproteins. By correlation of these spectra and comparison with spectra of reference glycopeptides and sialyl-lactose isomers it was possible to assign all signals belonging to anomeric, mannose H-2, sialic acid H-3 and N-acetyl protons. The number of the consituting monosaccharide residues of the oligomers can be obtained by integration of the above-mentioned signals. The chemical shifts of the anomeric and mannose H-2 protons give information about the type of glycan structure (mono-, bi-, triantennary) and the presence of terminal sialic acid at each of the antennas. The chemical shifts of sialic acid H-3 protons are typical for sialic acid residues in 2 leads to 3 or 2 leads to 6 linkage to galactose.

Carbohydrates↗
PubMed1978

[A new type of sialidosis with kidney disease: nephrosialidosis. I. Clinical, radiological and nosological study].

The term nephrosialidosis is proposed to describe a type of oligosaccharidosis in which a glomerular nephropathy develops early and causes death in the early years of life. The clinical and radiological features of the disease are dysmorphic facies, visceral storage disease, early and severe mental retardation and skeletal abnormalities of a type often described in this group of diseases. Foam cells were present in the marrow and, late in the illness, a cherry red spot was present on fundoscopy. The condition is inherited as an autosomal recessive. The leucocytes were deficient in alpha-(2-6) neuraminidase, an abnormality that has also been described in mucolipidosis type I and in other conditions quite distinct from nephrosialidosis. Thus the conditions characterised by this enzyme deficiency are definitely heterogeneous.

Eye Manifestations↗
PubMed1977

Sialidosis (mucolipidosis I).

The term "sialidosis" is suggested for the deficiency of alpha-neuraminidase activity in peripheral leukocytes and cultured fibroblasts which results in a considerable urinary excretion of sialyl-oligosaccharides. This defect was found in two siblings with a mild form of mucolipidosis I. 12 sialyl-acid rich oligosacharides have been isolated from the urine of the patients. The structure of ten of them has been determined. The studies of the patients show a remarkable variability of the clinical expression of this disease. The two siblings exhibited a progressive reduction of visual acuity, red-green blindness, a bilateral cherry red macular spot, punctate opacities of the lens, and minimal neurological symptoms. Morphologically, vacuolized lymphocytes, refringent inclusions in cultured fibroblasts, numerous cytoplasmatic inclusions containing a fine protein-like reticulum and some osmiophilic granules mainly in Kupffer's cells were found.

Adolescent↗
PubMed1976

Deficit in neuraminidase associated with mucolipidosis II (I-cell disease).

Using a tritiated sialyloligosaccharide as a substrate, the authors showed that mucolipidosis II is characterized by a lack of neuraminidase activity in leucocytes, while the other acidic hydrolases activities are normal. According to Ashwell, terminal galactose is the required signal for glycoproteins uptake by the cells. Thus, a neuraminidase deficit may explain the increase of sialylated hydrolases activities in the plasma and the non-recognition of these enzymes by cultured fibroblasts.

Humans↗