Prospecção e caracterização de peptaibols produzidos porlinhagem de Trichodermaasperellum

• Autor(a) principal: Brito, João Paulo Cabral de
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/3985
• topic: Trichoderma asperellum; Peptaibols; Espectrometria de massa; Asperelinas; Trichotoxinas; CIENCIAS BIOLOGICAS::BIOLOGIA GERAL

Trichoderma genus corresponds to free-living filamentous fungi, including species able to act as biological control agents against pathogenic fungi. It is believed that this ability is due to the synergy of several mechanisms, including a wide variety of secondary metabolites produced by these organisms. Among them, there is the production of peptaibols, an antibiotic peptide group characterized by the presence of non-proteinogenic amino acids such as α-aminoisobutyrate (Aib), presence of N-terminal modifications and amino alcohols in the C-terminal region. These peptaibols have amphipathic nature, allowing the formation of ion channels in lipid membranes, which are believed to be related to its antimicrobial activity. This study aimed to draw a profile of production and identify of secreted peptaibols from Trichoderma asperellum TR356 strain. The fungi was grown in TLE with 0.3% glucose medium for 5 days, 120 rpm in the dark. Liquid medium filtrate was used as metabolites source. These extracts were subjected to high performance liquid chromatography (HPLC) and subsequent analysis by matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF). The results indicate the production of two classes of peptaibols for this T. asperellum strain. Primary structure of two Asperelines (A and E) and five Trichotoxins (T5D2, T5E, T5F, and T5G 1717A) has been elucidated. Most of these peptaibols had been previously described in T. viride and T. asperellum marine strains. This is the first report of some of these compounds being produced by a T. asperellumstrain from soil. Future analysis will be necessary to elucidate the three-dimensional structures and their activity against pathogens.