一株纤维素降解菌株的分离鉴定及产酶特征研究  

Isolation,Identification of a Cellulose-producing Strain and Characterization of Cellulose-producing Capability

作　　者：尹礎[1,2] 夏乐先[1] 柳建设[1] 张维新 吴发登[1] 邱冠周[1] 

机构地区：[1]中南大学资源加工与生物工程学院,湖南长沙410083 [2]东莞市环保局麻涌分局,广东东莞523142

出　　处：《环境科学与技术》2009年第3期50-53,共4页Environmental Science & Technology

摘　　要：利用纤维素为唯一碳源的选择性培养基,通过平板分离法,从造纸废水处理池中分离出一株产纤维素酶菌株。经菌落及菌的形态观察,生理生化实验和16SrDNA鉴定,判断其为一株荧光假单胞菌,被命名为Pseudomonas fluorescens sp.strainYL。通过其生长曲线和产酶动力学研究,对数期比生长速率约为0.125h-1。纤维素酶的产生与细菌的生长紧密相关联。该菌在摇瓶培养中以微晶纤维素唯一碳源时,粗酶液的最高CMC酶活出现在培养78h,达到17.12U/mL。然而以微晶纤维素和葡萄糖作为复合碳源时产酶活性最高,70h左右达92.3U/mL,而以蔗糖作为碳源时活性很小。这些结果表明:仅具有还原性基团的低聚糖才可诱导产纤维素酶,大分子纤维素对酶的诱导表达效果不及小分子还原糖,其酶的诱导生成可能是通过小分子还原糖间接实现的。A cellulose-producing strain was isolated from reactor cell for pulp and papermaking wastewater by plate isolation, which was incubated in medium containing cellulose as only carbon source. The strain was named as YL and was identified as Pseudomonas fluorescens based on its biochemical and physiological property and analysis on 16S rDNA sequence. The growth rate was 0.125h^-1 in log growth phase. The crude enzymatic activity（CMC） was 17.12U/mL when grown in medium containing microcrystalline and incubated for 78h in flask. The generation of cellulose was closely correlated to its growth rate. However, the crude enzymatic activity was 92.3U/mL when glucose and microcrystalline were used as complex carbon source for bacterial growth. The crude enzymatic activity was small with sucrose as carbon source. Results indicated that only reduced-sugar with low molecular weight could induce the generation of cellulose. The induction by cellulose could be performed through low molecular weight reduced sugars which were the production of degraded cellulose.

关 键 词：纤维素酶 分离 菌 16S RDNA 荧光假单胞菌 

分 类 号：X172[环境科学与工程—环境科学]