Structural analysis of novel trehalose-based oligosaccharides from extremely stress-tolerant ascospores of Neosartorya fischeri (Aspergillus fischeri)

摘要

Different fungi, including the genera Neosartorya, Byssochlamys and Talaromyces, produce (asco)spores that survive pasteurization treatments and are regarded as the most stress-resistant eukaryotic cells. Here, the NMR analysis of a series of trehalose-based oligosaccharides, being compatible solutes that are accumulated to high levels in ascospores of the fungus Neosartorya fischeri, is presented. These oligosaccharides consist of an alpha,alpha-trehalose backbone, extended with one [alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 <-> 1)-alpha-D-Glcp; isobemisiose], two [alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 -> 1)-alpha-D-Glcp] or three [alpha-DGlcp-(1 -> 6)-alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 -> 1)-alpha-D-Glcp] glucose units. The tetra-and pentasaccharide, dubbed neosartose and fischerose, respectively, have not been reported before to occur in nature. (C) 2015 Elsevier Ltd. All rights reserved.