ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1
    facet.materialart.
    Unknown
    In-depth N-glycome profiling of paired colorectal cancer and non-tumorigenic tissues reveals cancer-, stage- and EGFR-specific protein N-glycosylation (2015)
    Oxford University Press
    Details
    Publication Date: 2015-08-28
    Description: Glycomics may assist in uncovering the structure–function relationships of protein glycosylation and identify glycoprotein markers in colorectal cancer (CRC) research. Herein, we performed label-free quantitative glycomics on a carbon-liquid chromatography–tandem mass spectrometry-based analytical platform to accurately profile the N-glycosylation changes associated with CRC malignancy. N -Glycome profiling was performed on isolated membrane proteomes of paired tumorigenic and adjacent non-tumorigenic colon tissues from a cohort of five males (62.6 ± 13.1 y.o.) suffering from colorectal adenocarcinoma. The CRC tissues were typed according to their epidermal growth factor receptor (EGFR) status by western blotting and immunohistochemistry. Detailed N -glycan characterization and relative quantitation identified an extensive structural heterogeneity with a total of 91 N -glycans. CRC-specific N-glycosylation phenotypes were observed including an overrepresentation of high mannose, hybrid and paucimannosidic type N -glycans and an under-representation of complex N -glycans ( P 〈 0.05). Sialylation, in particular α2,6-sialylation, was significantly higher in CRC tumors relative to non-tumorigenic tissues, whereas α2,3-sialylation was down-regulated ( P 〈 0.05). CRC stage-specific N-glycosylation was detected by high α2,3-sialylation and low bisecting β1,4-GlcNAcylation and Lewis-type fucosylation in mid-late relative to early stage CRC. Interestingly, a novel link between the EGFR status and the N-glycosylation was identified using hierarchical clustering of the N -glycome profiles. EGFR-specific N -glycan signatures included high bisecting β1,4-GlcNAcylation and low α2,3-sialylation (both P 〈 0.05) relative to EGFR-negative CRC tissues. This is the first study to correlate CRC stage and EGFR status with specific N -glycan features, thus advancing our understanding of the mechanisms causing the biomolecular deregulation associated with CRC.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Glycomic characterization of basal tears and changes with diabetes and diabetic retinopathy (2015)
    Oxford University Press
    Details
    Publication Date: 2015-01-30
    Description: As a secreted fluid, the state of tear glycosylation is particularly important in the role of immunity of the ocular surface. Tears are a valuable source of non-invasive biomarkers for disease and there are continued efforts to characterize their components thoroughly. In this study, a small volume of basal tears (5 μL) was collected from healthy controls, patients with diabetes without retinopathy and patients with diabetes and retinopathy. The detailed N- and O-linked tear protein glycome was characterized and the relative abundance of each structure determined. Of the 50 N-linked glycans found, 89% were complex with 50% containing a bisecting N- acetylglucosamine, 65% containing a core fucose whilst 33% were sialylated. Of the 8 O-linked glycans detected, 3 were of cores 1 and 5 of core 2 type, with a majority of them being sialylated (90%). Additionally, these glycan structures were profiled across the three diabetic disease groups. Whilst the higher abundant structures did not alter across the three groups, only five low abundance N-linked glycans and 1 O-linked glycan did alter with the onset of diabetes mellitus and diabetic retinopathy (DR). These results suggest the conservation of glycan types on basal tear proteins between individuals and point to only small changes in glycan expression on the proteins in tears with the development of diabetes and DR.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    The Third ACGG-DB Meeting Report: Towards an international collaborative infrastructure for glycobioinformatics (2012)
    Oxford University Press
    Details
    Publication Date: 2012-12-28
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Sweating the small stuff: Glycoproteins in human sweat and their unexplored potential for microbial adhesion (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: There is increasing evidence that secretory fluids such as tears, saliva and milk play an important role in protecting the human body from infection via a washing mechanism involving glycan-mediated adhesion of potential pathogens to secretory glycoproteins. Interaction of sweat with bacteria is well established as the cause of sweat-associated malodor. However, the role of sweat glycoproteins in microbial attachment has received little, if any, research interest in the past. In this review, we demonstrate how recent published studies involving high-throughput proteomic analysis have inadvertently, and fortuitously, exposed an abundance of glycoproteins in sweat, many of which have also been identified in other secretory fluids. We bring together research demonstrating microbial adhesion to these secretory glycoproteins in tears, saliva and milk and suggest a similar role of the sweat glycoproteins in mediating microbial attachment to sweat and/or skin. The contribution of glycan-mediated microbial adhesion to sweat glycoproteins, and the associated impact on sweat derived malodor and pathogenic skin infections are unchartered new research areas that we are beginning to explore.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Cystic fibrosis and bacterial colonization define the sputum N-glycosylation phenotype (2014)
    Oxford University Press
    Details
    Publication Date: 2014-11-28
    Description: Although mucin O-glycosylation of sputum from individuals suffering from cystic fibrosis (CF) is known to be altered relative to their unaffected counterparts, protein N-glycosylation of CF sputum remains structurally and functionally under-characterized. We report the first N -glycome of soluble proteins in sputum derived from five CF patients, two pathogen-free and two pathogen-infected/colonized non-CF individuals suffering from other pulmonary conditions. N -Glycans were profiled using porous graphitized carbon-liquid chromatography-negative ion-tandem mass spectrometry following enzymatic release from sputum proteins. The composition, topology and linkage isomers of 68 N -glycans were characterized and relatively quantified. Recurring structural features in all sputum N -glycomes were terminal α2,6-sialylation, α1,6-core fucosylation, β1,4-bisecting GlcNAcylation and compositions indicating paucimannosylation. Despite covering different genotypes, age, gender and microbial flora, the sputum N -glycomes showed little interpatient and longitudinal variation within CF patients. Comparative N -glycome analysis between inter-patient group revealed that lung infection/colonization, in general, extensively enriches the CF sputum N-glycosylation phenotype with paucimannose with simultaneous over-sialylation/fucosylation and under-bisecting GlcNAcylation of complex/hybrid N -glycans. In contrast, the sputum from CF patients had only slightly increased abundance of paucimannose N -glycans relative to pathogen-infected/colonized non-CF individuals. Similar to mucin O-glycosylation, protein N-glycosylation appears to be regulated primarily as a secondary effect of bacterial infection and inflammation rather than the CF pathogenesis in sputum. This study provides new structural N- glycan information to help understand the complex cellular and molecular environment of the CF affected respiratory tract.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    GlycoDigest: a tool for the targeted use of exoglycosidase digestions in glycan structure determination (2014)
    Oxford University Press
    Details
    Publication Date: 2014-10-18
    Description: : Sequencing oligosaccharides by exoglycosidases, either sequentially or in an array format, is a powerful tool to unambiguously determine the structure of complex N- and O- link glycans. Here, we introduce GlycoDigest, a tool that simulates exoglycosidase digestion, based on controlled rules acquired from expert knowledge and experimental evidence available in GlycoBase. The tool allows the targeted design of glycosidase enzyme mixtures by allowing researchers to model the action of exoglycosidases, thereby validating and improving the efficiency and accuracy of glycan analysis. Availability and implementation: http://www.glycodigest.org . Contact: matthew.campbell@mq.edu.au or frederique.lisacek@isb-sib.ch
    Print ISSN: 1367-4803
    Electronic ISSN: 1460-2059
    Topics: Biology , Computer Science , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Site-specific glycoproteomics confirms that protein structure dictates formation of N-glycan type, core fucosylation and branching (2012)
    Oxford University Press
    Details
    Publication Date: 2012-10-27
    Description: Growing evidence indicates that the individualized and highly reproducible N -glycan repertoires on each protein glycosylation site modulate function. Relationships between protein structures and the resulting N -glycoforms have previously been observed, but remain to be quantitatively confirmed and examined in detail to define the responsible mechanisms in the conserved mammalian glycosylation machinery. Here, we investigate this relationship by manually extracting and analyzing quantitative and qualitative site-specific glycoprofiling data from 117 research papers. Specifically, N -glycan structural motifs were correlated with the structure of the protein carriers, focusing on the solvent accessibility of the individual glycosylation sites and the physicochemical properties of the surrounding polypeptide chains. In total, 474 glycosylation sites from 169 mammalian N -glycoproteins originating from different tissues/body fluids were investigated. It was confirmed statistically that the N -glycan type, degree of core fucosylation and branching are strongly influenced by the glycosylation site accessibility. For these three N -glycan features, glycosylation sites carrying highly processed glycans were significantly more solvent-accessible than those carrying less processed counterparts. The glycosylation site accessibilities could be linked to molecular signatures at the primary and secondary protein levels, most notably to the glycoprotein size and the proportion of glycosylation sites located in accessible β-turns. In addition, the subcellular location of the glycoproteins influenced the formation of the N -glycan structures. These data confirm that protein structures dictate site-specific formation of several features of N -glycan structures by affecting the biosynthetic pathway. Mammals have, as such, evolved mechanisms enabling proteins to influence the N -glycans they present to the extracellular environment.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    MIRAGE: The minimum information required for a glycomics experiment (2014)
    Oxford University Press
    Details
    Publication Date: 2014-04-05
    Description: The MIRAGE (minimum information required for a glycomics experiment) initiative was founded in Seattle, WA, in November 2011 in order to develop guidelines for reporting the qualitative and quantitative results obtained by diverse types of glycomics analyses, including the conditions and techniques that were applied to prepare the glycans for analysis and generate the primary data along with the tools and parameters that were used to process and annotate this data. These guidelines must address a broad range of issues, as glycomics data are inherently complex and are generated using diverse methods, including mass spectrometry (MS), chromatography, glycan array-binding assays, nuclear magnetic resonance (NMR) and other rapidly developing technologies. The acceptance of these guidelines by scientists conducting research on biological systems in which glycans have a significant role will facilitate the evaluation and reproduction of glycomics experiments and data that is reported in scientific journals and uploaded to glycomics databases. As a first step, MIRAGE guidelines for glycan analysis by MS have been recently published (Kolarich D, Rapp E, Struwe WB, Haslam SM, Zaia J., et al. 2013. The minimum information required for a glycomics experiment (MIRAGE) project – Improving the standards for reporting mass spectrometry-based glycoanalytic data. Mol. Cell Proteomics. 12:991–995), allowing them to be implemented and evaluated in the context of real-world glycobiology research. In this paper, we set out the historical context, organization structure and overarching objectives of the MIRAGE initiative.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    FUT1 genetic variants impact protein glycosylation of porcine intestinal mucosa (2016)
    Oxford University Press
    Details
    Publication Date: 2016-04-28
    Description: A massive use of antibiotics in industrial pig production is a major cause of the rapidly rising bacterial resistance to antibiotics. An enhanced understanding of infectious diseases and of host–microbe interactions has the potential to explore alternative ways to improve pig health and reduce the need for antibiotics. Host–microbe interactions depend on host-expressed glycans and microbe-carrying lectins. In this study, a G 〉 A (nucleotide 307) missense mutation in the porcine α1,2fucosyltransferase 1 gene ( FUT1 ), which has been reported to prevent infections by the common porcine enteric pathogen F18 fimbriated Escherichia coli , provided a unique opportunity to study glycan structures potentially involved in intestinal infections. N- and O-Linked glycans of the intestinal mucosa proteins were characterized in detail using LC–MS/MS. Relative abundances of all glycans were determined and compared between four heterozygous pigs ( FUT1-307 A/G ) and four age-matched homozygous pigs from the same 2 litters carrying the missense FUT1 gene constellation ( FUT1-307 A/A ). None of the characterized 48 N - linked glycans was found to be regulated by the FUT1 missense mutation, while 11 of the O - linked glycans showed significantly altered abundances between the two genotypes. The overall abundance of H-antigen carrying structures was decreased fivefold, while H-antigen precursors and sialylated structures were relatively more abundant in pigs with the FUT1 missense mutation. These results provide insight into the role of FUT1 on intestinal glycosylation, improve our understanding of how variation in FUT1 can modulate host–microbe interactions, and suggest that the FUT1 genetic variant may help to improve pig gut health.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Comparative structural analysis of the glycosylation of salivary and buccal cell proteins: innate protection against infection by Candida albicans (2012)
    Oxford University Press
    Details
    Publication Date: 2012-10-27
    Description: Mucosal epithelial surfaces, such as line the oral cavity, are common sites of microbial colonization by bacteria, yeast and fungi. The microbial interactions involve adherence between the glycans on the host cells and the carbohydrate-binding proteins of the pathogen. Saliva constantly bathes the buccal cells of the epithelial surface of the mouth and we postulate that the sugars on the salivary glycoproteins provide an innate host immune mechanism against infection by competitively inhibiting pathogen binding to the cell membranes. The structures of the N - and O -linked oligosaccharides on the glycoproteins of saliva and buccal cell membranes were analyzed using capillary carbon liquid chromatography-electrospray ionization MS/MS. The 190 glycan structures that were characterized were qualitatively similar, but differed quantitatively, between saliva and epithelial buccal cell membrane proteins. The similar relative abundance of the terminal glycan epitope structures (e.g. ABO(H) blood group, sialylation and Lewis-type antigens) on saliva and buccal cell membrane glycoproteins indicated that the terminal N - and O -linked glycan substructures in saliva could be acting as decoy-binding receptors to competitively inhibit the attachment of pathogens to the surface of the oral mucosa. A flow cytometry-based binding assay quantified the interaction between buccal cells and the commensal oral pathogen Candida albicans . Whole saliva and released glycans from salivary proteins inhibited the interaction of C. albicans with buccal epithelial cells, confirming the protective role of the glycans on salivary glycoproteins against pathogen infection.
    Print ISSN: 0959-6658
    Electronic ISSN: 1460-2423
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...