title: Cerebrosides, extracellular glycolipids secreted by the selective lignin-degrading fungus Ceriporiopsis subvermispora.
abstract: Ceriporiopsis subvermispora is a selective white-rot fungus that degrades lignin at a site far from the hyphae and extracellular enzymes, without intensive damage to the cellulose. In selective ligninolysis, low molecular mass metabolites play a principal role and amphipathic substances are involved to control the degradation and transport of hydrophobic aromatic molecules, including lignin and lipids; however, secretion of the amphipathic substances by this fungus has not been well understood, except for alk(en)yl itaconates called ceriporic acids, which have a weak amphiphilicity. Herein, we report for the first time that the fungus secretes cerebrosides that are classified as glycosphingolipids. By using liquid chromatography electron spray ionization mass spectrometry (LC-ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy coupled with stable isotope feeding experiments with13C-glucose and15N-ammonium sulfate, the cerebrosides were determined to be N-hydroxyoctadecanoyl-1-O-β-d-glucopyranosyl-4E,8E-sphingadienine, N-hydroxyoctadecanoyl-1-O-β-d-glucopyranosyl-4E,8Z-sphingadienine, and N-hydroxyoctadecanoyl-1-O-β-d-glucopyranosyl-9-methyl-4E,8E-sphingadienine. The cerebrosides are strong amphipathic substances and potential metabolites for regulating difference and symbiosis within the microbial community.
authors.affiliation: Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto, Japan. Electronic address: hiroshi_nishimura@rish.kyoto-u.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishimura
authors.affiliation: Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamaguchi
authors.affiliation: Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D002554:Cerebrosides / Q000737:chemistry / Q000378:metabolism*; D055453:Coriolaceae / Q000378:metabolism*; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure
chemical_list: D002554:Cerebrosides; D008031:Lignin
keywords: Basidiomycete; Cerebroside; Glycolipid; White-rot fungi