两株降解纤维素真菌的分子鉴定及酶活分析

Identification of two cellulose degradation fungi and analysing its cellulose degradation enzyme activity

应用刚果红鉴定培养基,从土壤中筛选出两种分解纤维素能力较强的真菌,分别命名为NY01和NY02.滤纸条降解度分析显示,NY01的降解能力高于NY02.应用分子生物学手段,对两株菌rDNA的ITS区域序列分析显示,NY01与木霉的相似性高达99%,NY02与毛霉的相似性高达99%,暗示NY01可能是木霉的一个种,NY02可能是毛霉的一个种.培养基中碳氮比例对两株真菌纤维素降解酶活性的研究显示,在N/C比值较低和较高时,CMC酶和FPA酶活性都低,N/C比值在1∶8时酶活性最高,说明两株真菌降解纤维素的最佳N/C比值是1∶8.

Using congo red appraisal medium method, two fungi strains exhibiting strong cellulolytic ability, named NY01 and NY02, were screened from soil in this study. Filter paper was degradated more completely by NY01 than by NY02. Sequence analysing of fungi rDNA conservative domain amplified from NY01 and NY02 DNA using the primer pair of ITS1 and ITS4 showed that NY01 and NY02 had 99% similarity in nucleotide se- quence with Trichoderma and NY02 had 99% similarity in nucleotide sequence with Muco. The cellulose - en- zyme activity of the two cellulosedecomposing strains cultured on different glucose and （NH4）2SO4 content medi- um was analysised in this work. Results show that the CMC enzyme activity and FPA enzyme activity was highest when the C/N ratio was 1：8.