Gene expression in secondary metabolism and metabolic switching phase of Phanerochaete chrysosporium.

Ligninolytic enzymes are well-known to play the crucial roles in lignin biodegradation and have potential applications in industrial processes. The filamentous white-rot fungus, Phanerochaete chrysosporium, has been widely used as a model organism for studying these ligninolytic enzymes that are able to degrade the lignin during the secondary metabolism. To study the gene expression in secondary metabolism and metabolic switching phase of P. chrysosporium, we constructed a metabolic-switching phase suppression subtractive hybridization (SSH) cDNA library and a secondary metabolic phase SSH cDNA library to compare their mRNA expression profiles. We isolated the genes that are specially expressed and subsequently identified four genes that specially expressed during metabolic-switching phase while 22 genes in secondary metabolic phase. Accordingly, these specially expressed genes might play key roles in different metabolic stages, which would offer more new insights into the shift from nitrogen to lignin metabolism.