The structure of Cryptococcus neoformans galactoxylomannan contains beta-D-glucuronic acid

Analytical Services/Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA.
Carbohydrate research (Impact Factor: 1.93). 04/2009; 344(7):915-20. DOI: 10.1016/j.carres.2009.03.003
Source: PubMed


The structure of galactoxylomannan, a capsular polysaccharide from the opportunistic yeast Cryptococcus neoformans, was re-examined by NMR spectroscopy and GC-MS. The residue that is 3-linked to the side chain galactose and was previously assigned as beta-D-xylose [Vaishnav, V. V.; Bacon, B. E.; O'Neill, M.; Cherniak, R. Carbohydr. Res.1998, 306, 315-330] was determined to be beta-D-glucuronic acid. A revised structure for this polymer is presented, along with a proposal that this compound be termed glucuronoxylomannogalactan (GXMGal).

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    • "Samples were precipitated with cold 70% ethanol for 2 h, centrifuged at 15 000 × g, pellet dried and frozen at –80˚C until analysis. Glycosyl composition (Santander et al., 2013) and linkage ('methylation') (Heiss et al., 2009) analysis were performed as described previously. For NMR, the samples (~20 mg each) were deuteriumexchanged twice from D 2 O (99.9% D, Sigma-Aldrich, "
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