Comparative study of the genetic and environmental factors involved in the Induction of lignocellulolytic activities in the white rot basidiomycetes Pleurotus ostreatus and Polyporus tenuiculus cultured on different substrates

L RAMIREZ, ; A. OMARINI, ; G. PEREZ; F. SAMTOYO; G. PISABARRO

Edinburgh

Congreso; 9th International Mycological Congress: the biology of fungi; 2010

British Mycological Society, International Mycological Society, ELSEVIER

Pleurotus ostreatus is a model white rot basidiomycete in which the enzymatic and genetic elements involved in the degradation of lignocellulose have been extensively studied, and whose genome has been sequenced recently by the DOE- Joint Genome Institute. Polyporus tenuiculus, on the other hand, is another white rot basidiomycete placed in a different taxonomic branch for which the genomic, genetic and molecular information is scarce. In this paper, we compare the  lignocellulolytic strategies of these two fungi cultivated both in defined media and on solid substrates digging into the lignin degrading enzymatic activities and into the gene expression induced by compounds extracted from their natural growth substrates. Moreover, we have also studied the genetic plasticity and the effect of the environmental (culture) conditions on the expression of the genotype (Genotype-Environment Interaction, GXE) controlling the performance of these two fungi on the degradation of lignin by measuring the lignicellulolytic enzymatic activities at different temperatures (20, 25 y 30ºC) on different substrates (wheat straw and poplar sawdust). These studies permit to differentiate the qualitative value of a trait into parts corresponding to the strains, substrate, growth temperature, and to the interaction among all these factors.