Program Book - 27th Fungal Genetics Conference

FULL POSTER SESSION ABSTRACTSpasseckerianus gene silencing is being used to interfere with specific stages of biosynthesis, silenced transformed lines have been analysed bothchemically, to determine the impact of silencing on the metabolome of the organism, and via QRT-PCR, to determine the impact of silencing on thetranscription of the gene cluster. Heterologous expression of the entire gene cluster is being evaluated and analysed in the model basidiomyceteCoprinopsis cinerea. Engineered expression of the biosynthetic genes is being performed in the industrially relevant ascomycete Aspergillus oryzae to buildthe pathway in a stepwise manner. Progress in each of these areas will be presented.58. Improvement of Monascus pilosus for the production of functional foods by overexpression of the laeA gene. In H. Lee, Sang S. Lee, Jin H. Lee. Dept.of Advanced Fermentation Fusion Science & Technology, Kookmin Univ, Seoul, South Korea.Filamentous fungi Monascus species have been used to ferment rice producing red mold rice (RMR). They produce several bioactive compounds duringfermentation, however, they should have a potential to produce other bioactive compounds considering that most of fungi has many silent secondarymetabolite (SM) gene clusters. Therefore, we thought that Monascus species could be improved for functional food production by activation of such silentSM gene clusters. We overexpressed the laeA gene that is known to encode a global positive regulator of secondary metabolism under the alcA promoterin Monascus pilosus. An OE::laeA transformant produced more secondary metabolites including ones not detected under an uninduced condition. RMRfermented with the Monascus pilosus OE::laeA contained 7 times more monacolin K, a cholesterol lowering agent, than non-transformants increasing from2.45 to 15.59 mg/kg. In addition, the production of pigments was remarkably increased and antioxidant activity was increased as well. This study suggeststhat Monascus species that are important industrial fermentative fungi in Asia could be improved for the production of functional foods by overexpressionof the laeA gene.59. Molecular genetics studies on secondary metabolism in Chaetomium globosum reveal involvement of aureonitol and chaetoglobosins in generegulation and sexual reproduction. Takehito Nakazawa, kan'ichiro Ishiuchi, Satoru Sugimoto, Yasutaka Gotanda, Michio Sato, Hiroshi Noguchi, KenjiWatanabe. Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan.Chaetomium globosum has been reported to produce many natural products, secondary metabolites, with complex structures biosynthetic pathways ofwhich are very interesting to be elucidated such as aureonitol, chaetoglobosins, chaetocins and chaetoviridins. Recently, we developed molecular geneticssystems for understanding the secondary metabolism in this fungus: High frequency gene targeting by Cg.ligD disruption and the pyrG marker recycling.Then, we identified biosynthetic gene clusters for various natural products that had been isolated from C. globosum, and analyzed their biosyntheticmechanisms/pathways. We also obtained new natural products by changing an epigenetic regulation. During these studies, we found that some ofmutations in biosynthetic genes allowed us to obtain interesting phenotypes: drastic changes in secondary metabolism profiles and defects in productionof sexual spores. Here, we present that aureonitol and chaetoglobosins would play a critical role of controlling the productivity of secondary metabolitesand producting of sexual spores, respectively. A mutated gene of artH responsible for biosynthesizing aureonitol exhibits activating chaetoviridinsbiosynthesis and inactivating chaetoglocin A biosynthesis. A qRT-PCR analysis shows that transcriptional expressions of biosynthetic genes forchaetoviridins are activated, whereas those for chaetoglocins are inactivated by the mutated artH gene. Supplementation with aureonitol toDartH strain isobserved to inactivate chaetoviridins biosynthesis and transcriptional expression of their biosynthetic gene cluster. These results strongly suggest thataureonitol could be involved in transcriptional regulation of secondary metabolism in C. globosum. On the other hand, we also find chaetoglobosins isessential for production of sexual spores: Mutations in its biosynthetic genes clearly impair meiotic process. It is anticipated that chaetoglobosins areinvolved in meiotic process, because the mutants don’t affect formation of fruiting bodies (perithecia). Previously, chaetoglobosins were shown to inhibitactin polymerization in vitro. Therefore, chaetoglobosins would play a role of regulating actin or actin-related protein in C. globosum, which has beenreported to be associated with regulation of meiotic process as well as morphogenesis in fungi.60. Identification of T. asperellum CAZyme genes. Lasse Bech 1 , Morten Nedergaard Grell 1 , Peter Kamp Busk 1 , Hai Zhao 2 , Lene Lange 1 . 1) Section forSustainable Biotechnology, Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University Copenhagen, Denmark; 2)Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, PR China.To understand the complexity of enzymatic hydrolysis of plant cell walls and to discover new enzymes, one approach is to analyze cell wall degradingenzymes (CWDEs) in the transcriptome of plant degrading fungi like species of the genus Trichoderma. The Trichoderma spp. are ubiquitous colonizers ofcellulosic materials and are often be found where decaying plant material is available as well as in the rhizosphere of plants. Trichoderma spp. aresuccessful colonizers of their habitats, which is shown both by their efficient utilization of the biomass as well as their secretion capacity for antibioticmetabolites and enzymes. This study shows the transcriptome of Trichoderma asperellum isolated from duckweed. Duckweed is an aquatic plant that hasbeen shown to clean eutrophic water reservoirs for the production of biomass, which can be used as feed, fertilizer and fuel through the biorefineryplatform. The fungus was optimized for the production of CWDEs, where more than 200 glucoside hydrolases from 47 different families were identified.Several group members exhibited novel traits such as larger residue differences in active site and substrate binding site, hence making them interestingsubject for expression and further characterization. This data was compared with the hydrolysis of duckweed by enzyme blend from T. asperellum. Theenzyme blend showed a promising degree of hydrolysis of duckweed indicating that T. asperellum is a candidate for on-site enzyme production for theenzymatic hydrolysis of certain duckweed species. The transcriptome data can further be used to map the expression of CWDEs under different conditionsthereby coming closer to understanding the relationship between CWDEs and the plant cell wall.61. Identification of a lactose permease of Trichoderma reesei that is required for cellulase gene expression. Christa Ivanova 1 , Jenny Bååth 2 , BernhardSeiboth 1,3 , Christian Kubicek 1,3 . 1) Institute of Chemical Engineering, University of Technology of Vienna, 1060 Vienna, Austria; 2) Lund University, SE-22100 Lund, Sweden; 3) Austrian Institute of Industrial Biotechnology (ACIB) GmBH c/o Institute of Chemical Engineering, University of Technology of Vienna,1060 Vienna, Austria.The disaccharide lactose has been shown to be a potent inducer of cellulases in T. reesei, and it is virtually the only soluble waste product that can beused for commercial enzyme production. To understand the complex regulatory mechanisms underlying cellulase induction by lactose, we performedcomparative transcriptomic analysis using oligonuclotide arrays. Among the 410 genes that were upregulated over four-fold on lactose, were all cellulases,cellulase-enhancing proteins, major hemicellulases and also 63 MFS- (major facilitator superfamily) -permeases. The MFS permeases are characterized by12-transmembrane helices and a well conserved motif between TMS (transmembrane segment) 2 and 9. In order to investigate the function of thesetransporters, we generated deletion strains in T. reesei. For this, the 14 most-upregulated transporter encoding genes were chosen. One of thesedisruptant strains showed strongly impaired growth on lactose and was therefore chosen for further analysis. The strain showed impaired growth onlactose, whereas growth on glucose, glycerol and cellobiose remained unaltered, suggesting that the transporter is required for lactose uptake. The strainwas devoid of cellulase gene expression during cultivation on lactose, whereas it formed cellulases upon incubation with sophorose suggesting that it is136