2012; Röhrich et al 2013a, b; Chen et al 2013; Panizel et al 2

2012; Röhrich et al. 2013a, b; Chen et al. 2013; Panizel et al. 2013; Ren et al. 2013; Stoppacher et al. 2013), about 950 #LOXO-101 in vivo randurls[1|1|,|CHEM1|]# have been obtained from Trichoderma/Hypocrea species, thus confirming the genus as the most prolific source of this group of non-ribosomal peptide antibiotics (Brückner et al. 1991; Degenkolb and Brückner 2008; Brückner

et al. 2009). Both the taxonomic and metabolic diversity of Trichoderma/Hypocrea are hypothesised to originate from mycoparasitism or hyperparasitism, which may represent the ancestral life style of this genus (Kubicek et al. 2011). The unique bioactivities of peptaibiotics, resulting from their amphipathicity and helicity, make them ideal candidates to support the parasitic life style of their fungal producers: Under in vitro-conditions, the parallel formation of peptaibiotics such

as the 19-residue trichorzianins2 and of hydrolytic enzymes, above all chitinases and β-1,3-glucanases (Schirmböck et al. 1994), could be demonstrated. This observation led to a widely accepted model describing the synergistic interaction of peptaibiotics and hydrolases in the course of mycoparasitism of Trichoderma atroviride towards Botrytis cinerea (Lorito et al. 1996). Despite this, reports on in vivo-detection of peptaibiotics have scarcely been published in the past. MLN2238 Examples include the isolation of hypelcins A and B obtained from ca. 2 kg of dried, crushed stromata of the mycoparasite Hypocrea peltata (Fujita et al. 1984; Matsuura et al. 1993, 1994)3 as well as the detection of antiamoebins in herbivore dung, which have been produced by the coprophilous Stilbella fimetaria (syn. S. erythrocephala) (Lehr others et al. 2006). In order to close this gap, we initiated a screening

project aimed at resolving the question as to whether peptaibiotic production in vivo is a common adaptation strategy of Trichoderma/Hypocrea species for colonising and defending ecological niches: Several Hypocrea specimens were freshly collected in the natural habitat and analysed for the presence of peptaibiotics. Sequences of peptaibiotics found were independently confirmed by analysing the peptaibiome4 of pure agar cultures obtained by single-ascospore isolation from the specimens. Using liquid chromatography coupled to electrospray high resolution mass spectrometry we succeeded in detecting 28 peptaibiotics from the polyporicolous Hypocrea pulvinata (Röhrich et al. 2012). Another 49 peptaibiotics were sequenced in Hypocrea phellinicola, a parasite of Phellinus sp., especially Ph. ferruginosus (Röhrich et al. 2013a). Due to these encouraging results, our screening programme was extended to another nine specimens belonging to seven hitherto uninvestigated mycoparasitic or saprotrophic Trichoderma/Hypocrea species, respectively (Table 2).

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