Short Genome CommunicationsWhole-genome de novo sequencing of wood rot fungus Fomitopsis palustris (ATCC62978) with both a cellulolytic and ligninolytic enzyme system

- Whole genome sequencing results presented that F. palustris (ATCC 62978) has both cellulolytic and ligninolytic enzyme system.
- Three types of endoglucanases as cellulolytic enzyme and laccase, aromatic compound dioxygenase, and aryl alcohol dehydrogenase as ligninolytic enzymes were expressed in F. palustris (ATCC 62978).
- Endo-1,4-beta-d-glucanase (EC 3.2.1.4) (indicated in PacBio sequencing results) was identified as endoglucanase with 732 bp and it was highly expressed after 7 days in all conditions.

Fomitopsis palustris is a model brown rot fungus causing destructive wood decay based on the cellulase system. Endoglucanase secreted by F. palustris hydrolyzes cellulose in both the crystalline and amorphous form. In this study, whole-genome sequencing was conducted to identify genes related to F. palustris cellulose degradation and their functions. We determined the 43-Mb complete draft genome of F. palustris (ATCC 62978), comprising 14,592 predicted gene models. Gene annotation provided crucial information about the location and function of protein-encoding genes. Three types of endoglucanases were expressed: endo-1,3-beta-glucanase, endo-1,4-beta-d-glucanase, and endoglucanase. In addition, various ligninolytic enzymes such as laccase, aromatic compound dioxygenase, and aryl alcohol dehydrogenase were expressed in F. palustris (ATCC 62978). Colony polymerase chain reaction (PCR) indicated that the endo-1,4-beta-d-glucanase gene comprises 732 bp. Optimization of the expression conditions of endoglucanase by real-time PCR revealed that endoglucanase was highly expressed after 7 days in all conditions, which was secreted during the secondary metabolism. Studies for large-scale cellulase production from this fungus and investigation of its ligninolytic system will promote its extensive use in various applications. The genomic information determined herein provides a basis for molecular genetics studies to understand the genome functions of F. palustris (ATCC 62978).