Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oligosaccharides obtained from Saccharomyces cerevisiae mannoproteins by digestion with endo-N-acetyl-beta-D-glucosaminidase H were fractionated by anion-exchange chromatography, by elution with 50-100mM NaOH without or with a sodium-acetate gradient, and detected with a pulsed amperometric detector (PAD). The elution times of homologous oligosaccharides fell on a straight line having a slope characteristic of the structural type. The response of the PAD detector per mole of oligosaccharide increased about 2-fold going from Man3GlcNAc to Man13GlcNAc, and appeared to depend primarily on the oxidation of the reducing-end N-acetylglucosamine unit common to all the oligosaccharides. The digestion of a Man10GlcNAc with jack-bean alpha-mannosidase was monitored by injecting portions of the crude reaction mixture, and the intermediates were characterized by their elution positions and n.m.r. spectra in the anomeric proton region. One commercial jack-bean alpha-mannosidase preparation contained a novel endolytic activity that released N-acetylglucosamine from the reducing ends of the oligosaccharides and was shown to convert P----6 alpha Man----6 alpha Man----6 beta Man----4 alpha beta GlcNAc to P----6 alpha Man----6 alpha Man----6 alpha beta Man plus free N-acetylglucosamine. Another commercial jack-bean alpha-mannosidase converted the Man10GlcNAc to a Man3GlcNAc having the structure alpha Man----6 beta Man----4 alpha beta GlcNAc, [formula: see text] whereas the Oerskovia sp. alpha-mannosidase converted the same oligosaccharide to a Man4GlcNAc having the structure alpha Man----6 alpha Man----6 beta Man----4 alpha beta GlcNAc. [formula: see text]
 ...
PMID:Separation of yeast asparagine-linked oligosaccharides by high-performance anion-exchange chromatography. 222 97

Autolysis of isolated cell walls of Staphylococcus aureus strain Copenhagen was accompanied by the release of 1 mole of N-terminal alanine per mole of glutamic acid. No other N-terminal amino acids and no C-terminal amino acids were released. These observations indicated that complete hydrolysis of N-acetylmuramyl-l-alanine linkages ("amidase" action) had occurred. This was confirmed by fractionation and analysis of the products. Hydrolysis of 4-O-beta-N-acetylglucosaminyl-N-acetylmuramic acid linkages also occurred to a variable extent; on one occasion, complete degradation to disaccharides and hexosamine-free polypeptides (with intact pentaglycine cross-bridges) occurred. In one other instance, hydrolysis within pentaglycine bridges also occurred. Analyses of intact cell walls indicated that, in vivo, glycine endopeptidase activity was negligible and amidase activity was low, but that endo-beta-N-acetylglucosaminidase hydrolysed about 8% of the N-acetylglucosaminyl-N-acetylmuramic acid linkages. Autolysis of isolated cell walls was too slow for the enzymes isolated with them to have significant action during this isolation. The possible functions of these autolytic activities are discussed.
 ...
PMID:Mechanism of autolysis of isolated cell walls of Staphylococcus aureus. 577 31

Metabolic abnormalities in thyroid hormonogenesis cause congenital goiter. Here we studied a case of mild hypothyroidism caused by a novel missense mutation in the thyroglobulin (TG) gene. A female patient underwent thyroidectomy twice at the age of 27 and 43 years because of gradual enlargement of the thyroid. By RNase cleavage assay and PCR direct sequencing we identified a thymine to cytosine transition at nucleotide 3828 (from the transcription start site) which causes amino acid change from cysteine to arginine at codon 1263. A pedigree study suggested autosomal recessive inheritance due to consanguineous marriage of her parents. Immunohistochemical study suggested impaired intracellular transport of the mutant TG. Sensitivity to endoglycosidase H confirmed that the mutant TG failed to reach the Golgi compartment. Native polyacrylamide gel electrophoresis and Western blot analyses showed that formation of monomers and homodimers was defective with abundant high molecular-weight aggregates which are normally formed transiently after translation. To examine if the mutant TG is functionally defective, we separated thyroid tissue extract on a Biogel A5m column and measured T4 and T3 released from proteins in each fraction by treatment with proteinase K. Although thyroid hormones released per mole of the mutant TG protein did not decrease, those released per mg of total protein decreased. In conclusion, the missense mutation in the TG gene caused congenital goiter with mild hypothyroidism due to an altered protein structure which resulted in defective intracellular processing and premature degradation by "quality control" mechanisms. Although the tissue TG content was greatly reduced, the hypothyroidism was mild with slow progression of the goiter, because the mutant TG was a relatively good substrate for the synthesis of the thyroid hormones.
 ...
PMID:Missense mutation (C1263R) in the thyroglobulin gene causes congenital goiter with mild hypothyroidism by impaired intracellular transport. 979 Feb 65