Biochemical and molecular analysis of laccase secreted by white rot fungi from Misiones (Argentina) for biotechnological application.

ZAPATA PD, VILLALBA LL, SHIMIZU E, VÉLEZ RUEDA JO, MARTINA PF

Madison - USA

Congreso; 10th International Congress on Biotechnology in the Pulp and Paper Industry.; 2007

ICBPPI

Abstract. Laccase is one of the most important oxidative enzymes secreted from white rot fungi. There is a biotechnological implication in the pulp and paper industry related to its secretion. To achieve enzyme overexpression it is necessary to complete biochemistry and genetic characterization. Degradation studies in solid cultures revealed the occurrence of oxidative enzymes secreted by Ganoderma applanatum, Pycnoporus sanguineus and Peniophora sp. From these findings, further studies in liquid culture were sketched to determine laccase secretion. Peniophora sp achieved the highest laccase activity of 293 U/L and Pycnoporus sanguineus 237 U/L, both at 10 days of cultivation, whilst G. applanatum yielded 20 U/L at 14 days of cultivation. Since G. applanatum laccase gene sequence is unknown we carried out bioinformatic studies from 7 complete sequences available for lac gene at NCBI database (GeneBank) to characterize the involved gene. High homology regions of laccase genes among all seven fungi were detected. These findings are in agreement with the DNA band of 200 bp by PCR analysis found in the three fungi tested.