纤维素降解菌烟曲霉HZ1的基因组测序及生物信息学分析

Genome sequencing and bioinformatics analysis of cellulolytic fungus Aspergillus fumigatus HZ1

摘要:

[目的] 烟曲霉Aspergillus fumigatus作为一类具有纤维素降解能力的真菌，对其基因组的研究，将有利于从A.fumigatus中挖掘和开发利用与纤维素降解相关的酶资源。[方法] 利用CMC选择培养基和刚果红染色法从长足大竹象肠道中分离和筛选出纤维素降解菌A.fumigatus HZ1，同时采用Illumina PE150平台进行基因组测序，随后进行了相关的生物信息学分析，此外还利用了DNS法测定了其纤维素酶活。[结果] 纤维素降解菌A.fumigatus HZ1基因组大小为27.45 Mb，GC含量为49.43%；通过NR、KOG、GO、Swissprot、eggNOG、KEGG和Pfam数据库注释结果表明基因组包含9473个基因；同时碳水化合物活性酶（CAZyme）注释结果表明基因组含有534个CAZyme基因，并与其他4种A.fumigatus基因组CAZyme分布无显著差异；本研究还鉴定出多种与木质纤维素降解相关的纤维素酶基因、半纤维素酶基因和木质素酶基因；此外纤维素酶活结果表明，在CMC培养基中其酶活呈上升趋势且具有较高活性。[结论] 本研究首次对A.fumigatus HZ1基因组进行了测序和分析，探讨了其纤维素降解的遗传基础，并通过酶活验证了其纤维素降解潜力，为该菌的实际应用提供了理论基础。

关键词:烟曲霉HZ1;长足大竹象;基因组测序;生物信息学分析;纤维素酶;纤维素降解真菌

Abstract:

[Objective] Aspergillus fumigatus is a cellulolytic fungus. The research of its genome will facilitate the mining and development of enzyme resources associated with cellulose degradation. [Methods] A. fumigatus HZ1 was isolated from the gut of Cyrtotrachelus buqueti by CMC selective medium and Congo red staining method. Illumina PE50 platform was used to conduct genome sequence and the relative bioinformatics analysis was performed subsequently. Furthermore, the cellulase activities of this strain were determined by DNS method. [Results] The genome size of A. fumigatus HZ1 was 27.45 Mb with a GC content of 49.43%. The results from NR, KOG, GO, Swissprot, eggNOG, KEGG and Pfam database annotations reveal that the genome contained 9473 genes, and the carbohydrate active enzyme (CAZyme) annotation shows that the genome contained 534 CAZyme genes and coincided with the distribution of CAZyme in the other four A. fumigatus genomes. A variety of cellulase genes, hemicellulase genes and ligninase genes related to lignocellulose degradation were identified. In addition, cellulase activity showed an increasing trend and high activity in CMC medium. [Conclusion] Our findings provide reference for the application of A. fumigatus.

Key words:Aspergillus fumigatus HZ1;Cyrtotrachelus buqueti;genome sequence;bioinformatics analysis;cellulase;cellulolytic fungus