PubMed:827331 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PubMed/sourceid/827331","sourcedb":"PubMed","sourceid":"827331","source_url":"http://www.ncbi.nlm.nih.gov/pubmed/827331","text":"Determination of the linkages in some methylated, sialic acid-containing, meningococcal polysaccharides by mass spectrometry.\nThe application of gas-liquid chromatography-mass spectrometric (g.l.c.-m.s.) analysis to a number of sialic acid-containing polysaccharides of meningococcal origin has been studied. Methylation of these polysacchardies by the Hakomori conditions resulted in both O- and N-methylation. Methanolysis of the methylated polysaccharides from serogroup C [(2 leads to 9)-linked], colominic acid [(2 leads to 8)-linked], and serogroups Y and W-135 [both (1 leads to 4)-linked], yielded the respective 4,7,8-, 4,7,9-, and 7,8,9-tri-O-methyl derivatives of methyl N-acetyl-N-methyl-beta-D-neuraminate methyl glycoside. As model compounds, methyl N-acetyl-4,7,8,9-tetra-O-methyl-alpha-D-neuraminate methyl glycoside and its N-methyl derivative were also synthesized. All of the methylated derivatives could be identified on the basis of their typical fragmentation-patterns, indicating that this method is applicable to the determination of the position of linkages to sialic acid residues in biopolymers.","tracks":[{"project":"sentences","denotations":[{"id":"TextSentencer_T1","span":{"begin":0,"end":125},"obj":"Sentence"},{"id":"TextSentencer_T2","span":{"begin":126,"end":308},"obj":"Sentence"},{"id":"TextSentencer_T3","span":{"begin":309,"end":411},"obj":"Sentence"},{"id":"TextSentencer_T4","span":{"begin":412,"end":736},"obj":"Sentence"},{"id":"TextSentencer_T5","span":{"begin":737,"end":883},"obj":"Sentence"},{"id":"TextSentencer_T6","span":{"begin":884,"end":1122},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":125},"obj":"Sentence"},{"id":"T2","span":{"begin":126,"end":308},"obj":"Sentence"},{"id":"T3","span":{"begin":309,"end":411},"obj":"Sentence"},{"id":"T4","span":{"begin":412,"end":736},"obj":"Sentence"},{"id":"T5","span":{"begin":737,"end":883},"obj":"Sentence"},{"id":"T6","span":{"begin":884,"end":1122},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"attributes":[{"subj":"TextSentencer_T1","pred":"source","obj":"sentences"},{"subj":"TextSentencer_T2","pred":"source","obj":"sentences"},{"subj":"TextSentencer_T3","pred":"source","obj":"sentences"},{"subj":"TextSentencer_T4","pred":"source","obj":"sentences"},{"subj":"TextSentencer_T5","pred":"source","obj":"sentences"},{"subj":"TextSentencer_T6","pred":"source","obj":"sentences"},{"subj":"T1","pred":"source","obj":"sentences"},{"subj":"T2","pred":"source","obj":"sentences"},{"subj":"T3","pred":"source","obj":"sentences"},{"subj":"T4","pred":"source","obj":"sentences"},{"subj":"T5","pred":"source","obj":"sentences"},{"subj":"T6","pred":"source","obj":"sentences"}]},{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":781,"end":788},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"100829"},{"subj":"T1","pred":"source","obj":"NCBITAXON"}]},{"project":"GlyCosmos6-Glycan-Motif-Structure","denotations":[{"id":"T1","span":{"begin":50,"end":61},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T2","span":{"begin":228,"end":239},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T3","span":{"begin":1086,"end":1097},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"}],"attributes":[{"subj":"T1","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Structure"},{"subj":"T2","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Structure"},{"subj":"T3","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Structure"}]},{"project":"GlyCosmos6-Glycan-Motif-Image","denotations":[{"id":"T1","span":{"begin":50,"end":61},"obj":"Glycan_Motif"},{"id":"T2","span":{"begin":228,"end":239},"obj":"Glycan_Motif"},{"id":"T3","span":{"begin":1086,"end":1097},"obj":"Glycan_Motif"}],"attributes":[{"id":"A1","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A2","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A3","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"subj":"T1","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Image"},{"subj":"T2","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Image"},{"subj":"T3","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Image"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"sentences","color":"#93adec","default":true},{"id":"NCBITAXON","color":"#c7ec93"},{"id":"GlyCosmos6-Glycan-Motif-Structure","color":"#ec93e1"},{"id":"GlyCosmos6-Glycan-Motif-Image","color":"#93ecdc"}]}]}}