Resumo

MAYORGA-REYES, L. et al. Characterization and expression of the chitinase chit II gene from Lecanicillium lecanii in solid-state fermentation. Rev. Mex. Ing. Quím [online]. 2012, vol.11, n.1, pp.97-104. ISSN 1665-2738.

Hydrolytic enzymes like chitinase are key factors in entomopathogenic fungi infections of insects. Chitinolytic activity of Lecanicillium lecanii was detected when growing in chitin and in grasshopper cuticle (Sphenarium purpurascens) in solid-state fermentation (SSF); the highest levels were reached when the fungus grew in chitin. Expression levels of chitll gene in L. lecanii depend on the carbon source present in the medium, and an increment in chitll gene expression was observed through fermentation time. Among the carbon sources evaluated, chitin showed the highest levels of chitll gene expression. When grown in glucose, basal levels of expression of chitll gene were detected, suggesting that the L. lecanii chitinolytic system is subject to an induction/repression mechanism. Electrophoresis in SDS-PAGE of a partially purified extract obtained from the growth on chitin and S. purpurascens cuticle reveded a band of 23 kDa approximately with β-N-acetyi-glucosaminidase activity in a zymogram analysis.

Palavras-chave : chitinases; solid-state fermentation; RT-PCR; Lecanicillium lecanii; chitII gene.