title: Structures of wall heterogalactomannans isolated from three genera of entomopathogenic fungi.
abstract: O-linked heterogalactomannans with similar structural features have been purified from the fungal walls of the entomopathogenic fungi Lecanicillium muscarium, Beauveria bassiana, Beauveriabrongniartii, and Cordyceps sphingum. Their composition and structure have been determined using acid hydrolysis, methylation analysis, gas-liquid chromatography-mass spectrometry (GC-MS) and Nuclear magnetic resonance spectroscopy (NMR). All structures have an α-(1→6)-mannose backbone, but one of the two strains of L. muscarium included in this study contained an acidic heterogalactomannan instead of the neutral polysaccharide isolated in the rest of the species analyzed. Sequence analysis of the internal transcribed spacer (ITS) region of this strain indicated that it belongs to the related genus Simplicillium, displaying low identity (83%) with the closest Lecanicillium species. This is a new demonstration of the structural diversity of fungal wall heteromannans and validates their interest as chemotaxonomic markers. The production of a pullulan-like extracellular polysaccharide in strain CBS 413.70C of L. muscarium is also reported.
authors.affiliation: Departamento de Química Orgánica Biológica, Instituto de Química Orgánica, CSIC, Juan de la Cierva, Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Bernabé
authors.forename: Davinia
authors.initials: D
authors.lastname: Salvachúa
authors.forename: Jesús
authors.initials: J
authors.lastname: Jiménez-Barbero
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Leal
authors.forename: Alicia
authors.initials: A
authors.lastname: Prieto
mesh_terms: D000818:Animals; D052982:Beauveria / Q000737:chemistry* / Q000378:metabolism; D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000737:chemistry* / Q000378:metabolism; D032661:Cordyceps / Q000737:chemistry* / Q000378:metabolism; D005690:Galactose / Q000031:analogs & derivatives; D008401:Gas Chromatography-Mass Spectrometry; D006999:Hypocreales / Q000737:chemistry* / Q000378:metabolism; D007313:Insecta / Q000382:microbiology; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D010572:Pest Control, Biological / Q000295:instrumentation
chemical_list: D008351:Mannans; C012990:galactomannan; D005690:Galactose