Taxonomic group: fungi / Basidiomycota
(Phylum: Basidiomycota)
Host organism: Homo sapiens
Organ / tissue: cell wallAssociated disease: infection due to Cryptococcus neoformans [ICD11:
XN3EH 
]
The structure was elucidated in this paperNCBI PubMed ID: 11083830Publication DOI: 10.1128/IAI.68.12.7049-7060.2000Journal NLM ID: 0246127Publisher: American Society for Microbiology
Correspondence: immgceu
microbio.ufrj.br
Institutions: Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, Disciplina de Biologia Celular, Universidade Federal de San Paulo, San Paulo, Brazil
A major ceramide monohexoside (CMH) was purified from lipidic extracts of Cryptococcus neoformans. This molecule was analyzed by high-performance thin-layer chromatography (HPTLC), gas chromatography coupled with mass spectrometry, and fast atom bombardment-mass spectrometry. The cryptococcal CMH is a β-glucosylceramide, with the carbohydrate residue attached to 9-methyl-4,8-sphingadienine in amidic linkage to 2-hydroxyoctadecanoic acid. Sera from patients with cryptococcosis and a few other mycoses reacted with the cryptococcal CMH. Specific antibodies were purified from patients' sera by immunoadsorption on the purified glycolipid followed by protein G affinity chromatography. The purified antibodies to CMH (mainly immunoglobulin G1) bound to different strains and serological types of C. neoformans, as shown by flow cytofluorimetry and immunofluorescence labeling. Transmission electron microscopy of yeasts labeled with immunogold-antibodies to CMH and immunostaining of isolated cell wall lipid extracts separated by HPTLC showed that the cryptococcal CMH predominantly localizes to the fungal cell wall. Confocal microscopy revealed that the β-glucosylceramide accumulates mostly at the budding sites of dividing cells with a more disperse distribution at the cell surface of nondividing cells. The increased density of sphingolipid molecules seems to correlate with thickening of the cell wall, hence with its biosynthesis. The addition of human antibodies to CMH to cryptococcal cultures of both acapsular and encapsulated strains of C. neoformans inhibited cell budding and cell growth. This process was complement-independent and reversible upon removal of the antibodies. The present data suggest that the cryptococcal β-glucosylceramide is a fungal antigen that plays a role on the cell wall synthesis and yeast budding and that antibodies raised against this component are inhibitory in vitro.
glucosylceramide, antifungal antibodies, Fonsecaea pedrosoi
Structure type: monomer ; 754 [M-H]-
Location inside paper: p.7052, fig.3, GSL
Compound class: glycosphingolipid, cerebroside
Contained glycoepitopes: IEDB_137339,IEDB_142488,IEDB_146664,IEDB_983931,SB_192,SB_5
Methods: FAB-MS, GC-MS, sugar analysis, GLC, extraction, HPTLC, CC, transmission electron microscopy
Biological activity: reacted with sera from patients with cryptococcosis, histoplasmosis, aspergillosis and paracoccidioidomycosis
Related record ID(s): 40549, 40812, 40813, 40814, 42250, 42251, 42252, 42253, 42254, 42255, 42256, 42257, 42258, 42259, 42260, 42261, 42262, 42263, 42264, 42265, 42266, 42267, 42268, 42269, 42270, 42271, 42272, 42273, 42274, 42275, 42279, 42280, 42281, 42282, 42287, 42288, 43402, 43403, 43418, 43419, 43420, 43679, 43680
NCBI Taxonomy refs (TaxIDs): 5207
Show glycosyltransferases
There is only one chemically distinct structure:
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