Author(s): CORREA, K. C. S.; FACCHINATO, W. M.; HABITZREUTER, F. B.; RIBEIRO, G. H.; RODRIGUES, L. G.; MICOCCI, K. C.; CAMPANA-FILHO, S. P.; COLNAGO, L. A.; SOUZA, D. H. F.

Summary: Abstract: This study evaluates the activity of a recombinant chitinase from the leaf-cutting ant Atta sexdens (AsChtII-C4B1) against colloidal and solid ?- and ?-chitin substrates. 1H NMR analyses of the reaction media showed the formation of N-acetylglucosamine (GlcNAc) as the hydrolysis product. Viscometry analyses revealed a reduction in the viscosity of chitin solutions, indicating that the enzyme decreases their molecular masses. Both solid state 13C NMR and XRD analyses showed minor differences in chitin crystallinity pre- and post-reaction, indicative of partial hydrolysis under the studied conditions, resulting in the formation of GlcNAc and a reduction in molecular mass. However, the enzyme was unable to completely degrade the chitin samples, as they retained most of their solid-state structure. It was also observed that the enzyme acts progressively and with a greater activity on ?-chitin than on ?-chitin. AsChtII-C4B1 significantly changed the hyphae of the phytopathogenic fungus Lasiodiplodia theobromae, hindering its growth in both solid and liquid media and reducing its dry biomass by approximately 61%. The results demonstrate that AsChtIIC4B1 could be applied as an agent for the bioproduction of chitin derivatives and as a potential antifungal agent.

Publication year: 2024

Types of publication: Journal article

Unit: Embrapa Instrumentation

Keywords: Fungicide, Insect chitinase