LAUSR

To investigate the diversity of gastrointestinal microflora and lignocellulose-degrading enzymes in wild Asian elephants, three wild Asian elephants living in the same group were selected for study from the Wild Elephant Valley in Xishuangbanna nature reserve of Yunnan Province, China. The fresh fecal samples from the three wild Asian elephants were analyzed by metagenomic sequencing to study the diversity of their gastrointestinal microbes and cellulolytic enzymes. There were a high abundance of Firmicutes and a higher abundance of hemicellulose-degrading hydrolases than cellulose-degrading hydrolases in the wild Asian elephants. Furthermore, there were high abundance and rich diversity of carbohydrate active enzymes (CAZymes) obtained from the gene set annotation of the three samples, the majority of them showed low identity with the CAZy database entry. About half of the CAZymes had no species source at the phylum and genus level. These indicated that the wild Asian elephants might possess greater ability to digest hemicellulose than cellulose to provide energy, and the gastrointestinal tract of wild Asian elephants might be a potential source of novel efficient lignocellulose-degrading enzymes. Therefore, the exploitation and utilization of these enzyme resources would help us to alleviate the current energy crisis and ensure food security.