Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography
The brain N-glycome is known to be crucial for many biological functions, including its involvement in neuronal diseases. Although large structural studies of brain N-glycans were recently carried out, a comprehensive isomer-specific structural analysis has still not been achieved, as indicated by t...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-01-01
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| Series: | Biomolecules |
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| Online Access: | https://www.mdpi.com/2218-273X/12/1/85 |
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| author | Johannes Helm Lena Hirtler Friedrich Altmann |
| author_facet | Johannes Helm Lena Hirtler Friedrich Altmann |
| author_sort | Johannes Helm |
| collection | DOAJ |
| description | The brain N-glycome is known to be crucial for many biological functions, including its involvement in neuronal diseases. Although large structural studies of brain N-glycans were recently carried out, a comprehensive isomer-specific structural analysis has still not been achieved, as indicated by the recent discovery of novel structures with galactosylated bisecting GlcNAc. Here, we present a detailed, isomer-specific analysis of the human brain N-glycome based on standardized porous graphitic carbon (PGC)-LC-MS/MS. To achieve this goal, we biosynthesized glycans with substitutions typically occurring in the brain N-glycome and acquired their normalized retention times. Comparison of these values with the standardized retention times of neutral and desialylated N-glycan fractions of the human brain led to unambiguous isomer specific assignment of most major peaks. Profound differences in the glycan structures between naturally neutral and desialylated glycans were found. The neutral and sialylated N-glycans derive from diverging biosynthetic pathways and are biosynthetically finished end products, rather than just partially processed intermediates. The focus on structural glycomics defined the structure of human brain N-glycans, amongst these are HNK-1 containing glycans, a bisecting sialyl-lactose and structures with fucose and <i>N</i>-acetylgalactosamine on the same arm, the so-called LDNF epitope often associated with parasitic worms. |
| first_indexed | 2024-03-10T01:49:47Z |
| format | Article |
| id | doaj.art-2679bb32eda149dd832403799969a3a3 |
| institution | Directory Open Access Journal |
| issn | 2218-273X |
| language | English |
| last_indexed | 2024-03-10T01:49:47Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biomolecules |
| spelling | doaj.art-2679bb32eda149dd832403799969a3a32023-11-23T13:06:50ZengMDPI AGBiomolecules2218-273X2022-01-011218510.3390/biom12010085Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon ChromatographyJohannes Helm0Lena Hirtler1Friedrich Altmann2Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, AustriaCenter for Anatomy and Cell Biology, Division of Anatomy, Medical University of Vienna, Währinger Straße 13, A-1090 Vienna, AustriaDepartment of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, AustriaThe brain N-glycome is known to be crucial for many biological functions, including its involvement in neuronal diseases. Although large structural studies of brain N-glycans were recently carried out, a comprehensive isomer-specific structural analysis has still not been achieved, as indicated by the recent discovery of novel structures with galactosylated bisecting GlcNAc. Here, we present a detailed, isomer-specific analysis of the human brain N-glycome based on standardized porous graphitic carbon (PGC)-LC-MS/MS. To achieve this goal, we biosynthesized glycans with substitutions typically occurring in the brain N-glycome and acquired their normalized retention times. Comparison of these values with the standardized retention times of neutral and desialylated N-glycan fractions of the human brain led to unambiguous isomer specific assignment of most major peaks. Profound differences in the glycan structures between naturally neutral and desialylated glycans were found. The neutral and sialylated N-glycans derive from diverging biosynthetic pathways and are biosynthetically finished end products, rather than just partially processed intermediates. The focus on structural glycomics defined the structure of human brain N-glycans, amongst these are HNK-1 containing glycans, a bisecting sialyl-lactose and structures with fucose and <i>N</i>-acetylgalactosamine on the same arm, the so-called LDNF epitope often associated with parasitic worms.https://www.mdpi.com/2218-273X/12/1/85brainN-glycansporous graphitic carbonbrain glycomicsnegative mode CID |
| spellingShingle | Johannes Helm Lena Hirtler Friedrich Altmann Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography Biomolecules brain N-glycans porous graphitic carbon brain glycomics negative mode CID |
| title | Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography |
| title_full | Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography |
| title_fullStr | Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography |
| title_full_unstemmed | Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography |
| title_short | Towards Mapping of the Human Brain N-Glycome with Standardized Graphitic Carbon Chromatography |
| title_sort | towards mapping of the human brain n glycome with standardized graphitic carbon chromatography |
| topic | brain N-glycans porous graphitic carbon brain glycomics negative mode CID |
| url | https://www.mdpi.com/2218-273X/12/1/85 |
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