Taxonomic group: fungi / Ascomycota
(Phylum: Ascomycota)
Host organism: Homo sapiens
Organ / tissue: hypha,
eumycotic mycetomaAssociated disease: eumycetoma [ICD11:
1F29 
];
infection due to Pseudallescheria boydii [ICD11:
XN6BV ]
The structure was elucidated in this paperNCBI PubMed ID: 16766532Publication DOI: 10.1074/jbc.M511417200Journal NLM ID: 2985121RPublisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
Correspondence: Bozza MT <mbozza
micro.ufrj.br>; Barreto-Bergter E <eliana.bergter
micro.ufrj.br>
Institutions: Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, Departamento de Bioquímica, Universidade Federal do Paraná, Parańa, Brazil, National Institute for Biological Standards and Control, Hertfordshire, UK
The host response to fungi is in part dependent on activation of evolutionarily conserved receptors, including toll-like receptors and phagocytic receptors. However, the molecular nature of fungal ligands responsible for this activation is largely unknown. Herein, we describe the isolation and structural characterization of an α-glucan from Pseudallescheria boydii cell wall and evaluate its role in the induction of innate immune response. These analyses indicate that α-glucan of P. boydii is a glycogen-like polysaccharide consisting of linear 4-linked α-D-Glcp residues substituted at position 6 with α-D-Glcp branches. Soluble α-glucan, but not β-glucan, led to a dose-dependent inhibition of conidia phagocytosis. Furthermore, a significant decrease in the phagocytic index occurred when α-glucan from conidial surface was removed by enzymatic treatment with α- amyloglucosidase, thus indicating an essential role of α-glucan in P. boydii internalization by macrophages. α-Glucan stimulates the secretion of inflammatory cytokines by macrophages and dendritic cells; again this effect is abolished by treatment with α-amyloglucosidase. Finally, α-glucan induces cytokine secretion by cells of the innate immune system in a mechanism involving toll-like receptor 2, CD14, and MyD88. These results might have relevance in the context of infections with P. boydii and other fungi, and α-glucan could be a target for intervention during fungal infections.
phagocytosis, glucan, toll-like receptors, cytokine, Pseudallescheria boydii, CD14 antigen
Structure type: structural motif or average structure
Location inside paper: p. 22618, table 2, p. 22619, Fig. 2, B
Compound class: O-polysaccharide, O-glycoprotein, glucan
Contained glycoepitopes: IEDB_140629,IEDB_142488,IEDB_144998,IEDB_146664,IEDB_420417,IEDB_420418,IEDB_420419,IEDB_420421,IEDB_857742,IEDB_983931,SB_192
Methods: 13C NMR, 1H NMR, methylation, GC-MS, ELISA, acid hydrolysis, GC, biological assays, GPC, enzymatic digestion, extraction, acetylation, HPTLC, cytokine production, phenol-sulfuric acid assay, phagocytosis assay, Folin phenol reagent method
Biological activity: α-glucan induces TNF release by macrophages through TLR2 and CD14; the secretion of TNF induced by α-glucan was abolished from MyD88-/- macrophages; α-glucan participates in the phagocytosis of conidia and that TLR2 and CD14 are involved in the innate immune activation upon the recognition of α-glucan
Comments, role: the structure shown in fig.2 contains a terminal α-D-Glcp residue that contradicts polymeric structure; location of ''C'' mark seems to be erroneous. NMR data assigments were corrected by CSDB stuff (NMR data for residue C were assigned for branched -4,6)aDGlcp(1- residue; NMR data for residue A were assigned to residue marked C in the paper
Related record ID(s): 45019
NCBI Taxonomy refs (TaxIDs): 5597Reference(s) to other database(s): GTC:G65541PQ
Show glycosyltransferases
NMR conditions: in D2O / TSP at 333 K
[as TSV]
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6
4,4,4 aDGlcp 100.5 72.2 73.9 78.0 71.9 61.3
4,4,6,4 aDGlcp 100.5 72.5 73.6 70.1 73.4 61.3
4,4,6 aDGlcp 100.5 72.2 73.9 78.0 71.9 61.3
4,4 aDGlcp 99.2 ? ? 78.8 ? ?
4 aDGlcp 100.5 72.2 73.9 78.0 71.9 61.3
aDGlcp 100.5 72.2 73.9 78.0 71.9 61.3
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6
4,4,4 aDGlcp 5.39 3.66 3.96 3.66 3.88 3.87
4,4,6,4 aDGlcp 5.39 3.62 3.71 3.44 3.79 3.86
4,4,6 aDGlcp 5.39 3.66 3.96 3.66 3.88 3.87
4,4 aDGlcp 4.98 3.61 4.00 3.65 3.89 ?
4 aDGlcp 5.39 3.66 3.96 3.66 3.88 3.87
aDGlcp 5.39 3.66 3.96 3.66 3.88 3.87
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6
4,4,4 aDGlcp 100.5/5.39 72.2/3.66 73.9/3.96 78.0/3.66 71.9/3.88 61.3/3.87
4,4,6,4 aDGlcp 100.5/5.39 72.5/3.62 73.6/3.71 70.1/3.44 73.4/3.79 61.3/3.86
4,4,6 aDGlcp 100.5/5.39 72.2/3.66 73.9/3.96 78.0/3.66 71.9/3.88 61.3/3.87
4,4 aDGlcp 99.2/4.98 ?/3.61 ?/4.00 78.8/3.65 ?/3.89 ?/?
4 aDGlcp 100.5/5.39 72.2/3.66 73.9/3.96 78.0/3.66 71.9/3.88 61.3/3.87
aDGlcp 100.5/5.39 72.2/3.66 73.9/3.96 78.0/3.66 71.9/3.88 61.3/3.87
1H NMR data:
| Linkage | Residue | H1 | H2 | H3 | H4 | H5 | H6 |
|---|
| 4,4,4 | aDGlcp | 5.39 | 3.66 | 3.96 | 3.66 | 3.88 | 3.87 |
| 4,4,6,4 | aDGlcp | 5.39 | 3.62 | 3.71 | 3.44 | 3.79 | 3.86 |
| 4,4,6 | aDGlcp | 5.39 | 3.66 | 3.96 | 3.66 | 3.88 | 3.87 |
| 4,4 | aDGlcp | 4.98 | 3.61 | 4.00 | 3.65 | 3.89 | ? |
| 4 | aDGlcp | 5.39 | 3.66 | 3.96 | 3.66 | 3.88 | 3.87 |
| | aDGlcp | 5.39 | 3.66 | 3.96 | 3.66 | 3.88 | 3.87 |
|
13C NMR data:
| Linkage | Residue | C1 | C2 | C3 | C4 | C5 | C6 |
|---|
| 4,4,4 | aDGlcp | 100.5 | 72.2 | 73.9 | 78.0 | 71.9 | 61.3 |
| 4,4,6,4 | aDGlcp | 100.5 | 72.5 | 73.6 | 70.1 | 73.4 | 61.3 |
| 4,4,6 | aDGlcp | 100.5 | 72.2 | 73.9 | 78.0 | 71.9 | 61.3 |
| 4,4 | aDGlcp | 99.2 | ? | ? | 78.8 | ? | ? |
| 4 | aDGlcp | 100.5 | 72.2 | 73.9 | 78.0 | 71.9 | 61.3 |
| | aDGlcp | 100.5 | 72.2 | 73.9 | 78.0 | 71.9 | 61.3 |
|
![](nmr_drawer.py?width=750&height=130&nucleus=C&rotate_labels=false&spectrum=[{"s":100.5,"l":"1","c":[0,0,225]},{"s":72.2,"l":"2","c":[0,0,225]},{"s":73.9,"l":"3","c":[0,0,225]},{"s":78,"l":"4","c":[0,0,225]},{"s":71.9,"l":"5","c":[0,0,225]},{"s":61.3,"l":"6","c":[0,0,225]},{"s":100.5,"l":"1","c":[230,0,30]},{"s":72.5,"l":"2","c":[230,0,30]},{"s":73.6,"l":"3","c":[230,0,30]},{"s":70.1,"l":"4","c":[230,0,30]},{"s":73.4,"l":"5","c":[230,0,30]},{"s":61.3,"l":"6","c":[230,0,30]},{"s":100.5,"l":"1","c":[0,165,0]},{"s":72.2,"l":"2","c":[0,165,0]},{"s":73.9,"l":"3","c":[0,165,0]},{"s":78,"l":"4","c":[0,165,0]},{"s":71.9,"l":"5","c":[0,165,0]},{"s":61.3,"l":"6","c":[0,165,0]},{"s":99.2,"l":"1","c":[120,0,225]},{"s":78.8,"l":"4","c":[120,0,225]},{"s":100.5,"l":"1","c":[0,192,255]},{"s":72.2,"l":"2","c":[0,192,255]},{"s":73.9,"l":"3","c":[0,192,255]},{"s":78,"l":"4","c":[0,192,255]},{"s":71.9,"l":"5","c":[0,192,255]},{"s":61.3,"l":"6","c":[0,192,255]},{"s":100.5,"l":"1","c":[220,0,180]},{"s":72.2,"l":"2","c":[220,0,180]},{"s":73.9,"l":"3","c":[220,0,180]},{"s":78,"l":"4","c":[220,0,180]},{"s":71.9,"l":"5","c":[220,0,180]},{"s":61.3,"l":"6","c":[220,0,180]}])
The spectrum also has 4 signals at unknown positions (not plotted). |
There is only one chemically distinct structure:
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Found 1 record.
Displayed record 1
(later renamed to: Scedosporium boydii)