摘要：
伞菌目Agaricales隶属于担子菌门Basidiomycota、伞菌亚门Aga rico mycotina,是担子菌门中最大的一个类群,能够以腐生、寄生以及共生的模式在自然环境中生存,生存范围广,对于维持生态环境的平衡具有重要的作用.本研究基于51株伞菌目真菌基因组大数据挖掘降解木质纤维素相关的碳水化合物活性酶(carbohydrate-active enzymes,CAZymes)和氧化还原酶(oxidoreductases),同时比较白腐菌、褐腐菌、腐生菌、菌根菌、植物致病菌、兼性寄生菌、动物共生菌和不明生态型真菌降解机制的差异.结果显示白腐菌和褐腐菌等木腐菌、菌根菌、兼性寄生菌、其他腐生菌、植物致病菌以及共生菌的CAZymes家族平均数目为134个、93个、101个、127个、61个和32个,而CAZymes同源的基因平均数目为398个、240个、463个、407个、418个、131个和38个,木腐菌的CAZymes家族最为丰富,但是兼性寄生菌基因数目最多;同时具有木质纤维素降解酶活性的26个家族中,基因数目分别为86个、32个、101个、86个、104个、36个和10个.在木腐菌(白腐菌和褐腐菌)、菌根菌、兼性寄生菌、腐生菌、不明生态型、植物致病菌和动物共生菌中氧化还原酶相关的基因数目为44个、35个、48个、53个、59个、6个和29个,其中不明生态型真菌的基因数目最多达到了59个,植物致病菌的数量最少.CAZymes和氧化还原酶在不同的真菌中数量和种类差别很大,与其生态类型的关系不明显,此研究丰富了木质纤维素降解机制的多样性,但是需要进一步的实验设计对其生物活性进行验证以及进行蛋白家族进化分析.%Order Agaricales belonging to Basidiomycota,Agaricomycotina is the most abundant group in fungal kingdom.Fungi belonging to Agaricales could be highly effective saprophytes and parasites or symbionts of other plants or animals,which play important roles in maintaining environmental balance.The compositions of carbohydrate-active enzymes (CAZymes) and oxidoreductases in 51 fungal strains were revealed based on 51 fungal genomes and the differences of degradation mechanism of white-rot (WR),brown-rot (BR),saprobic (S),mycorrihizal (M),plant-pathogenic (PP),facultatively parasitic (FP),and animal-symbiotic (AS) fungi and other fungi of unknown ecological (N) and nutritive types were compared.The results revealed the average numbers of CAZymes families detected were 134,93,101,127,93,61 and 32,and the numbers of the genes belonging to different CAZymes families was 398,240,463,407,418,131 and 38 in wood-decaying (white-rot and brown-rot),saprobic,mycorrihizal,facultatively parasitic,other unknown ecological type,plant-pathogenic and animal-symbiotic fungi,respectively.Wood-decaying fungi covered the most abundant CAZymes families and parasitic and saprobic fungi had the highest number of genes homologous to CAZymes.The average number of genes related to lignocellulose degradation was 86,32,101,86,104,36 and 10 in WD (wood decaying),M,FP,S,N,PP and AS respectively.The average number of oxidoreductases in the fungi above-mentioned was 44,35,48,53,59,6 and 29.CAZymes and oxidoreductases in Agaricales varied significantly and the diversity of them was very high.There was no obvious relationship between enzymes related CAZymes and oxidoreductases and ecological types.This research enriched the diversity of mechanisms of degradation of lignocellulose,however,the activities of enzymes need experimental designs for verification and further evolution analyses of protein family.
