Taxonomic group: fungi / Basidiomycota
(Phylum: Basidiomycota)
Organ / tissue: capsuleAssociated disease: infection due to Cryptococcus neoformans [ICD11:
XN3EH 
];
infection due to Cryptococcus gattii [ICD11:
XN0LE ]
The structure was elucidated in this paperNCBI PubMed ID: 1773425Publication DOI: 10.1016/0008-6215(91)84149-9Journal NLM ID: 0043535Publisher: Elsevier
Institutions: Department of Chemistry, Laboratory of Microbial and Biochemical Sciences, Georgia State University, Atlanta, USA
The major extracellular polysaccharide (glucuronoxylomannan, GXM) from six strains of Cryptococcus neoformans serotype B was characterized by gas-liquid chromatography (g.l.c.), g.l.c.-mass spectrometry (g.l.c.-m.s.), and nuclear magnetic resonance (n.m.r.) spectroscopy. Ultrasonic irradiation (u.i.) was used to reduce the mol.wt. of native GXM from 975000 to 115000 without apparent change in its composition (GXM-S). The Xylp:Manp:GlcpA molar ratio of the GXM and GXM-S from the six strains of C. neoformans serotype B is approximately 3.5:3.0:0.6. GXM-S was O-deacetylated (GXM-D) by treatment with NH4OH. The 13C-n.m.r. analysis of GXM-D gave spectra that served as characteristic fingerprints of the structure and also facilitated the assignment of the anomeric carbon resonances to specific structural moieties present in GXM-D. The GXM-D from each serotype B strain was found to be similar by 13C-n.m.r. spectroscopy. The structure contains a linear (1→3)-α-d-Manp backbone substituted with 2-O-β-GlcpA and 2-O-β-Xylp. β-Xylp is also O-4 linked to the Manp substituted with GlcpA. In addition, a model for the disposition of the Xylp and GlcpA side chain substituents along the mannopyranan backbone is proposed, based upon results from the combination of g.l.c.-m.s. and 13C-n.m.r. spectroscopy.
NMR, GLC-MS, Cryptococcus neoformans, Glucuronoxylomannan
Structure type: suggested polymer biological repeating unit
Location inside paper: p.114, GXM-D, table III, fig.3
Trivial name: glucuronoxylomannan (GXM), glucuronoxylomannan
Compound class: CPS, EPS, O-polysaccharide, O-antigen, cell wall polysaccharide, polysaccharide, glucuronoxylomannan, capsule polysaccharide
Contained glycoepitopes: IEDB_114701,IEDB_115136,IEDB_115576,IEDB_130701,IEDB_140116,IEDB_140630,IEDB_144983,IEDB_145668,IEDB_152206,IEDB_164174,IEDB_167188,IEDB_174332,IEDB_2270799,IEDB_423153,IEDB_76933,IEDB_983930,SB_197,SB_44,SB_67,SB_72
Methods: 13C NMR, 1H NMR, deacetylation, acid hydrolysis, GLC, GPC, ion-exchange chromatography, extraction, acetylation, reduction, ethanol precipitation, sonication, Blumenkrantz method, HETCOR
Comments, role: chemical repeating unit frame was shifted for compatibility with structures elucidated by MS [Eukaryotic Cell 2007, 6: 1464-1473]; published erroneous 13C NMR chemical shifts of #_aDManp C2 (72.12) and #3_aDManp C2 (72.12) were removed by the CSDB staff (the published spectrum indicated the presence of aDManp unsubstituted at C2). The published 13C NMR spectrum in DSS was shifted 1.6 ppm upfield by CSDB staff to accord to a TMS reference.
Related record ID(s): 40816, 42130, 43808, 43816, 43822, 43825, 43917, 44110, 44281, 44286, 44351
NCBI Taxonomy refs (TaxIDs): 37769Reference(s) to other database(s): GTC:G42955PN
Show glycosyltransferases
NMR conditions: in D2O / DSS; pH 7.6 at 343 K
[as TSV]
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6
3,3,2 bDGlcpA 102.39 73.73 75.55 72.73 77.70 178.37
3,3,4 bDXylp 105.10 73.75 76.73 70.36 66.20
3,3 aDManp 101.75 ? ? ? ? ?
3,2 bDXylp 105.95-106.09 73.75 76.73 70.36 66.20
3 aDManp 102.36-102.95 ? 79.60 ? ? 61.83
2 bDXylp 105.95-106.09 73.75 76.73 70.36 66.20
aDManp 102.36-102.95 ? 79.60 ? ? 61.83
1H NMR data: present in publication
|
13C NMR data:
| Linkage | Residue | C1 | C2 | C3 | C4 | C5 | C6 |
|---|
| 3,3,2 | bDGlcpA | 102.39 | 73.73 | 75.55 | 72.73 | 77.70 | 178.37 |
| 3,3,4 | bDXylp | 105.10 | 73.75 | 76.73 | 70.36 | 66.20 | |
| 3,3 | aDManp | 101.75 | ? | ? | ? | ? | ? |
| 3,2 | bDXylp | 105.95
106.09 | 73.75 | 76.73 | 70.36 | 66.20 | |
| 3 | aDManp | 102.36
102.95 | ? | 79.60 | ? | ? | 61.83 |
| 2 | bDXylp | 105.95
106.09 | 73.75 | 76.73 | 70.36 | 66.20 | |
| | aDManp | 102.36
102.95 | ? | 79.60 | ? | ? | 61.83 |
|
![](nmr_drawer.py?width=750&height=130&nucleus=C&rotate_labels=false&spectrum=[{"s":102.39,"l":"1","c":[0,0,225]},{"s":73.73,"l":"2","c":[0,0,225]},{"s":75.55,"l":"3","c":[0,0,225]},{"s":72.73,"l":"4","c":[0,0,225]},{"s":77.7,"l":"5","c":[0,0,225]},{"s":178.37,"l":"6","c":[0,0,225]},{"s":105.1,"l":"1","c":[230,0,30]},{"s":73.75,"l":"2","c":[230,0,30]},{"s":76.73,"l":"3","c":[230,0,30]},{"s":70.36,"l":"4","c":[230,0,30]},{"s":66.2,"l":"5","c":[230,0,30]},{"s":101.75,"l":"1","c":[0,165,0]},{"s":106.02,"l":"1","c":[120,0,225]},{"s":73.75,"l":"2","c":[120,0,225]},{"s":76.73,"l":"3","c":[120,0,225]},{"s":70.36,"l":"4","c":[120,0,225]},{"s":66.2,"l":"5","c":[120,0,225]},{"s":102.66,"l":"1","c":[0,192,255]},{"s":79.6,"l":"3","c":[0,192,255]},{"s":61.83,"l":"6","c":[0,192,255]},{"s":106.02,"l":"1","c":[220,0,180]},{"s":73.75,"l":"2","c":[220,0,180]},{"s":76.73,"l":"3","c":[220,0,180]},{"s":70.36,"l":"4","c":[220,0,180]},{"s":66.2,"l":"5","c":[220,0,180]},{"s":102.66,"l":"1","c":[100,160,0]},{"s":79.6,"l":"3","c":[100,160,0]},{"s":61.83,"l":"6","c":[100,160,0]}])
The spectrum also has 11 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: Cryptococcus gattii VGI B)