title: Screening the biosphere: the fungicolous fungus Trichoderma phellinicola, a prolific source of hypophellins, new 17-, 18-, 19-, and 20-residue peptaibiotics.
abstract: To investigate the significance of antibiotics for the producing organism(s) in the natural habitat, we screened a specimen of the fungicolous fungus Trichoderma phellinicola (syn. Hypocrea phellinicola) growing on its natural host Phellinus ferruginosus. Results revealed that a particular group of non-ribosomal antibiotic polypeptides, peptaibiotics, which contain the non-proteinogenic marker amino acid, α-aminoisobutyric acid, was biosynthesized in the natural habitat by the fungicolous producer and, consequently, released into the host. By means of liquid chromatography coupled to electrospray high-resolution time-of-flight mass spectrometry, we detected ten 20-residue peptaibols in the specimen. Sequences of peptaibiotics found in vivo were independently confirmed by analyzing the peptaibiome of an agar plate culture of T. phellinicola CBS 119283 (ex-type) grown under laboratory conditions. Notably, this strain could be identified as a potent producer of 39 new 17-, 18-, and 19-residue peptaibiotics, which display the same building scheme as the 20-residue peptaibols found in the specimen. Two of the 19-residue peptaibols are tentatively assigned to carry tyrosinol, a novel C-terminal residue, as deduced from high-resolution tandem mass-spectrometry data. For the new peptaibiotics produced by T. phellinicola, the name 'hypophellin(s)', based on the teleomorph name, is introduced.
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Bioresources Project Group, Winchesterstrasse 2, D-35394 Giessen. christian.roehrich@ime.fraunhofer.de
authors.forename: Christian René
authors.initials: CR
authors.lastname: Röhrich
authors.forename: Anita
authors.initials: A
authors.lastname: Iversen
authors.forename: Walter Michael
authors.initials: WM
authors.lastname: Jaklitsch
authors.forename: Hermann
authors.initials: H
authors.lastname: Voglmayr
authors.forename: Andreas
authors.initials: A
authors.lastname: Vilcinskas
authors.forename: Kristian Fog
authors.initials: KF
authors.lastname: Nielsen
authors.forename: Ulf
authors.initials: U
authors.lastname: Thrane
authors.forename: Hans
authors.initials: H
authors.lastname: von Döhren
authors.forename: Hans
authors.initials: H
authors.lastname: Brückner
authors.forename: Thomas
authors.initials: T
authors.lastname: Degenkolb
mesh_terms: D000595:Amino Acid Sequence; D000621:Aminoisobutyric Acids / Q000302:isolation & purification*; D002853:Chromatography, Liquid; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D054848:Peptaibols / Q000737:chemistry / Q000302:isolation & purification*; D014242:Trichoderma / Q000737:chemistry*
chemical_list: D000621:Aminoisobutyric Acids; D054848:Peptaibols