Navegando por Palavras-chave "galactofuranose"

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    Analysis of glycosylinositol phosphorylceramides expressed by the opportunistic mycopathogen Aspergillus fumigatus
    (Amer Soc Biochemistry Molecular Biology Inc, 2007-08-01) Toledo, Marcos S. [UNIFESP]; Levery, Steven B.; Bennion, Beau; Guimaraes, Luciana L. [UNIFESP]; Castle, Sherry A.; Lindsey, Rebecca; Momany, Michelle; Park, Chaeho; Straus, Anita Hilda [UNIFESP]; Takahashi, Helio Kiyoshi [UNIFESP]; Univ New Hampshire; Universidade Federal de São Paulo (UNIFESP); Univ Georgia
    Acidic glycosphingolipid components were extracted from the opportunistic mycopathogen Aspergillus fumigatus and identified as inositol phosphorylceramide and glycosylinositol phosphorylceramides (GIPCs). Using nuclear magnetic resonance sppectroscopy, mass spectrometry, and other techniques, the structures of six major components were elucidated as Ins-P-Cer (Af-0), Manp (alpha 1 -> 3) Manp(alpha 1 -> 2) Ins-P-Cer (Af-2), Manp(a1 -> 2) Manp (alpha 1 -> 3) Manp(alpha 1 -> 2) Ins-P-Cer (Af-3a), Manp(a1 -> 3) [Galf(beta 1 -> 6)] Manp(alpha 1 -> 2)-Ins-P-Cer (Af-3b), Manp (alpha 1 -> 2)-Manp(alpha 1 -> 3)[ Galf(beta 1 -> 6)] Manp(beta 1 -> 2) Ins-P-Cer (Af-4), and Manp(alpha 1 -> 3) Manp(alpha 1 -> 6) GlcpN(alpha 1 -> 2) Ins-P-Cer (Af-3c) ( where Ins 5 myo-inositol and P = phosphodiester). A minor A. fumigatus GIPC was also identified as the N-acetylated version of Af-3c (Af-3c*), which suggests that formation of the GlcN alpha 1 -> 2Ins linkage may proceed by a two-step process, similar to the GlcN alpha 1 -> 2Ins linkage in glycosylphosphatidylinositol (GPI) anchors (transfer of GlcNAc, followed by enzymatic de-N-acetylation). the glycosylinositol of Af-3b, which bears a distinctive branching Galf (b1Y6) residue, is identical to that of a GIPC isolated previously from the dimorphic mycopathogen Paracoccidioides brasiliensis (designated Pb-3), but components Af-3a and Af-4 have novel structures. Overlay immunostaining of A. fumigatus GIPCs separated on thinlayer chromatograms was used to assess their reactivity against sera from a patient with aspergillosis and against a murine monoclonal antibody (MEST-1) shown previously to react with the Galf (beta 1 -> 6) residue in Pb-3. These results are discussed in relation to pathogenicity and potential approaches to the immunodiagnosis of A. fumigatus.
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    A monoclonal antibody directed to terminal residue of beta-galactofuranose of a glycolipid antigen isolated from Paracoccidioides brasiliensis; Cross-reactivity with Leishmania major and Trypanosoma cruzi
    (Oxford Univ Press, 1997-06-01) Suzuki, Erika [UNIFESP]; Toledo, Marcos Sergio de [UNIFESP]; Takahashi, Helio Kiyoshi [UNIFESP]; Straus, Anita Hilda [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    A mouse monoclonal antibody, MEST-1, was produced against Band 1 glycolipid antigen of Paracoccidioides brasiliensis, the glycan structure of Band 1 antigen was recently elucidated and the monosaccharides sequence was defined as: Galf beta 1-->6(Manp alpha 1-->3)Manp beta 1-->2Ins. the reactivity of MEST-1 MAb was determined by solid-phase radioimmunoassay and high performance thin layer chromatography immunostaining. Selective oxidation of galactofuranose residues and inhibition assays with different methyl-glycosides, revealed that MAb MEST-1 is directed against the terminal residue of beta-D-gaiactofuranose of Band 1, a phosphoglyceroglycolipid antigen of P.brasiliensis. By indirect immunofluorescence, it was observed that the epitope recognized by MEST-1 is accessible to the antibody in yeast forms of this fungus. Reactivity of MEST-1 with parasites known to express galactofuranose containing glycoconjugates was also analyzed by indirect immunofluorescence. A positive fluorescence was observed with promastigotes of Leishmania major and epimastigotes of Trypanosoma cruzi, GIPL-1 was identified as the antigen recognized by MEST-1 in Leishmania major, indicating that the MAb MEST-1 recognizes terminal galactofuranose residue in either beta 1-->6 or beta 1-->3 linkage to the mannose.