Transcriptome analysis of Termitomyces albuminosus reveals the biodegradation of lignocellulose.
OBJECTIVE
To study whether Termitomyces albuminosus can degrade lignocelluloses and to understand the symbiotic relationship between termite mushroom and fungus-growing termite.


METHODS
cDNA library of T. albuminosus was sequenced by the Roche 454 GS FLX Titanium platform, and the diverse enzymes relevant to degradation of cellulose and lignin of symbiotic fungus T. albuminosus were analyzed.


RESULTS
Eighth sequencing run resulted in a total of 82386 reads (express sequence tags, EST). After removing the vector and primer sequences, the remained 54410 reads were assembled into 3301 contigs and 3193 singletons. Comparing sequence similarity with known proteins, these sequences, representing approximately 2681 unique genes, were successfully annotated using BLAST searches (E-value < or = 1e(-10)) against the Nr, SwissProt and CDD databases. The T. albuminosus transcripts included 33 enzymes putatively involved in cellulose and hemicelluloses biodegradation. 5 enzymes could hydrolyze cellulose and others had catalytic activities for degradation of hemicelluloses, starch and glycogen and chitin. Moreover, four genes encoding laccases and a single aryl-alcohol oxidase which could degrade lignin were also identified. These results revealed symbiosis fungus T. albuminosus had many laccases and possibly decomposed phenolic compounds from plant litter.


CONCLUSIONS
Data presented in this study indicated that T. albuminosus had the ability to degrade lignin, which made cellulose more easily degraded by the cellulase produced by fungus-growing termite.
School of Life Sciences, Yunnan Normal University, Kunming 650500, China. fangyang09@163.com
Fang
F
Yang
Bo
B
Xu
Junjun
J
Li
Zunxi
Z
Huang
D000595:Amino Acid Sequence; D001673:Biodegradation, Environmental; D020869:Gene Expression Profiling; D008031:Lignin / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D055434:Termitomyces / Q000145:classification / Q000378:metabolism*
C036909:lignocellulose; D008031:Lignin