Mota, Mariana GomesRego, Maria Cecília FarinhaCabanas, Andreia Sofia Pereira2014-02-062014-02-062013Cabanas, A.S.P. - Avaliação da atividade antifúngica de quitinases de macieira. Lisboa: ISA, 2013, 76 p.http://hdl.handle.net/10400.5/6474Mestrado em Engenharia Agronómica - Instituto Superior de AgronomiaThis work focused on the expression of cloned heterologous chitinase genes in order to produce the corresponding recombinant proteins. Constructs harbouring the three chitinase genes (C525, C209, C203) cloned in GS115 and KM71H strains were expressed in culture medium with methanol as carbon source at 30ºC. Culture growth and total soluble protein content were assessed periodically. The resulting secretomes were dialised, freeze-dried and used in assays of biological efficacy regarding inhibition of mycelial growth and spores germination of Botrytis cinerea. First assays were conducted at 20ºC with 1 mg of total protein in the initial solution. Both strains were analysed, varying also the temperature and the amount of protein assayed (to 2.5 mg). Secretome production was more efficient in the strain GS115H during 120 h and 144 h. The construct that showed higher efficacy in the biological assays was the C209 EN cloned in GS115. Assays with Ilyonectria macrodydima, Stemphylium sp. and Venturia inaequalis, were also conducted and showed some inhibition potential of construct C203EN towards Stemphylium sp.porchitinasefungicidebiological effectivenessBotrytis cinereaPichia pastorismaster thesis201845598