一株降解纖維素木霉的分離與鑒定
      
       
摘要：從湖南科技大學(xué)溢香園中一株木棉樹腐敗的根部分離篩選得到1株產(chǎn)纖維素酶較好的木霉菌株cx004。酶活力實(shí)驗(yàn)表明菌株經(jīng)發(fā)酵培養(yǎng)5d，產(chǎn)酶酶活達(dá)到最高；活性在pH4-7內(nèi)穩(wěn)定；pH值為6時(shí)酶活最高，50℃處理1h活性穩(wěn)定。采用傳統(tǒng)的分類學(xué)方法和鏡檢觀察，結(jié)果表明該菌株與綠木霉(Trichoderma virens)菌到表現(xiàn)特征非常相似。為了進(jìn)一步確定cx004的分類學(xué)地位，測(cè)定了其ITS序列，分析了相關(guān)木霉相應(yīng)序列的同源性，構(gòu)建了分子系統(tǒng)發(fā)育樹，結(jié)果表明菌株cx004與綠木霉菌(Trichoderma virens)的親緣關(guān)系最近。綜合上述結(jié)果，菌株cx004可鑒定為綠木霉菌（T. virens ）

關(guān)鍵詞：纖維素酶；綠木霉菌；ITS序列；酶活性

Isolation and identification of a cellulose-degrading strain of Trichoderma
     
Technology　　
Abstract: ＡTrichoderma strain cx004 showing efficient cellulose-biodegrading ability was isolated and purified from a rotten Ceiba in Yixiangyuan park of Hunan University of Science and Technology（HNUST）. The metabolites showed strong cellulase activity after cultured for 5 days.This activity remained stable at 50°C from pH 4 to 7. The cellulase ability reached the highest at pH 6. The results of traditional taxology methods and microscope observation showed that the strain is very similar to Trichoderma virens in most of the phenotypes in tradional physiological and biochemical aspects, as well as in molucular phylogenetic dendrogram built from relatively ITS gene sequences, with which the related strains were compared. Therefore, strain cx004 was identificed as Trichoderma virens.
Key words:  cellulase; Trichoderma virens; ITS sequence; enzyme activity.