title: Novel neogala-series glycosphingolipids with terminal mannose and glucose residues from Hirsutella rhossiliensis, an aureobasidin A-resistant ascomycete fungus.
abstract: Hirsutella rhossiliensis, a nematophagous fungus belonging to the Ascomycota, is resistant to aureobasidin A (AbA). In this fungus, the biosynthetic pathway leading to mannosylinositolphosphoceramides, which is inhibited by AbA, was not detected. Instead, this fungus contains neutral complex glycosphingolipids (GSLs) and monoglycosylceramides. Except for monoglycosylceramides, neutral GSLs share a neogala-series core structure, Galbeta1-6Galbeta1-Cer. Among the GSLs of H. rhossiliensis, three novel GSLs with terminal Man and Glc residues on the sugar chain were elucidated. We analyzed GSL structure using compositional sugar, fatty acid, and sphingoid analyses, methylation analysis, matrix-assisted laser desorption ionization time-of-flight/mass spectrometry (MALDI-TOF MS), and (1)H nuclear magnetic resonance spectroscopy (NMR). The following structures were determined: Manalpha1-3Galbeta1-6Galbeta1-6Galbeta1-Cer; Glcalpha1-2Galbeta1-6Galbeta1-6Galbeta1-Cer; and Manalpha1-3Galbeta1-6(Glcalpha1-4)Galbeta1-6Galbeta1-Cer. In the ceramides, the fatty acids were predominantly saturated h24:0-acids and the sphingoids were predominately t18:0- or t18:1-sphingoids. In contrast, the ceramides of Glcbeta1-Cer contained d18:2- and d19:2-sphingoids. These findings indicate the presence of a novel biosynthetic pathway of neogala-series GSLs in fungi.
authors.affiliation: Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan. yasu-t@lif.kyoto-u.ac.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tani
authors.forename: Tori
authors.initials: T
authors.lastname: Funatsu
authors.forename: Hisashi
authors.initials: H
authors.lastname: Ashida
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ito
authors.forename: Saki
authors.initials: S
authors.lastname: Itonori
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Sugita
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D001203:Ascomycota / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry; D002518:Ceramides / Q000737:chemistry; D002849:Chromatography, Gas; D047630:Depsipeptides / Q000737:chemistry*; D005227:Fatty Acids / Q000737:chemistry; D005658:Fungi / Q000737:chemistry; D005947:Glucose / Q000737:chemistry*; D006028:Glycosphingolipids / Q000737:chemistry; D006801:Humans; D006999:Hypocreales; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008358:Mannose / Q000737:chemistry*; D013058:Mass Spectrometry; D020383:Neutral Glycosphingolipids / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D002241:Carbohydrates; D002518:Ceramides; D047630:Depsipeptides; D005227:Fatty Acids; D006028:Glycosphingolipids; D020383:Neutral Glycosphingolipids; C071398:aureobasidin A; D005947:Glucose; D008358:Mannose