真菌对磺胺二甲氧嘧啶降解过程的转录组分析及差异表达基因的功能分析

Transcriptomic analysis and differentially expressed genes identification of fungi upon degradation of sulfadimethoxine

采用黄孢原毛平革菌降解磺胺二甲氧嘧啶(SDM),4 d后SDM的去除率达74%,降解速率达3.24 mg·L^(-1)·d^(-1).采用Illumina高通量测序平台对降解SDM后的菌株与对照组菌株进行测序,通过GO和KEGG富集分析,得到的差异表达基因能显著富集到与降解相关的"氧化还原酶活性"途径,及与应激反应有关的"ABC转运体"路径.通过对高表达高上调的差异表达基因的筛选与分析,得到了耐受和降解SDM的功能基因.水通道蛋白、ABC转运蛋白及甲基转运酶基因等在黄孢原毛平革菌对环境的耐受中起到重要的作用.乙醇氧化酶、细胞色素P450和糖苷水解酶等在黄孢原毛平革菌对SDM的降解中起着关键的作用.本文从转录组水平分析了SDM的降解机制,为黄孢原毛平革菌在环境修复中的应用提供一定的参考.

This study evaluated the fungal degradation of sulfamethazine(SDM) by white-rot Phanerochaete chrysosporium(P. chrysosporium). The removal rate of SMD reached 74% at day 4, and the degradation rate was 2.34 mg·L^(-1)·d^(-1). The transcriptome sequencing of P. chrysosporium was performed using the Illumina high-throughput sequencing platform to understand the degradation mechanism of SDM. Profiling and functional analysis of differentially expressed genes using Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) revealed that the degradation of SDM was related to "oxidoreductase activity" and "ABC transporters" were involved in the stress response to SDM. Further examination of upregulated genes upon exposure to SDM showed that ethanol oxidase, cytochrome P450 and glycoside hydrolase played key roles in the biodegradation process, and aquaporin, ABC transporters and methyltransferase genes were critical for the tolerance of the fungus to SDM. This research enhances our understanding of the degradation mechanism of SDM at the transcriptome level and suggestes a potential application of P. chrysosporium in environmental remediation.