β-Galactofuranose-containing structures present in the cell wall of the saprophytic fungus Cladosporium (Hormoconis) resinae

A peptidogalactomannan was isolated from mycelia of Cladosporium (Hormoconis) resinae and characterized using methylation fragmentation analysis, partial acid hydrolysis and H-1 and C-13-NMR spectroscopy The galactomannan component was a branched structure and consisted of a main chain containing (1 -> 6)-linked alpha-D-Manp residues substituted at O-2 by side chains containing (1 -> 2)-linked alpha-D-Manp residues. beta-D-Galf residues were present as side chains of 3-4 units that are (1 -> 5)-interlinked This structure is very similar to a pGM isolated from Aspergillus fumigatus and differs from that of Cladosporium wernecka (currently named Hortaea werneckit), with this pGM and other fungal galactomannans having single terminal (1 -> 6)-linked beta-Galf residues. The importance of the carbohydrate moiety of Cladosportum resinae pGM in immunoassays was also demonstrated. On FACS examination, a decrease (60%) in rabbit serum anti- C. resinae binding to C resinae conidia occurred when this serum had been previously incubated with pGMs from C resinae and A fumigatus or with mannoprotein from Candida parapsilosis, suggesting the presence of cross-reactive determinants in these fungi (C) 2010 Elsevier Masson SAS All rights reserved.