一株高温兼性纤维素降解细菌的分离鉴定及特性分析  

Isolation and identification of a thermophilic cellulolytic facultative anaerobic bacterium and analysis of its properties

作　　者：田敏[1,2] 张庆华[1,2,3] 毛忠贵[1,2] 张建华[1,2] 

机构地区：[1]江南大学生物工程学院,江苏无锡214122 [2]工业生物技术教育部重点实验室,江苏无锡214122 [3]江西农业大学生物科学与工程学院,南昌330045

出　　处：《安全与环境学报》2013年第2期31-36,共6页Journal of Safety and Environment

基　　金：国家863项目(2008AA10Z338);江苏省科技支撑计划项目(BE2011623)

摘　　要：从一组高效的纤维素降解复合菌系中分离纤维素降解菌,并对分离菌的相关特性进行初步研究。以微晶纤维素和滤纸为唯一碳源对复合菌系进行连续富集培养,分离得到一株能够有效降解滤纸的高温兼性厌氧纤维素降解细菌FLJ1,通过16S rRNA基因序列分析、滤纸降解试验和酶谱分析对该菌的特性进行了研究。经形态观察、生理生化试验及系统发育进化树分析可知,FLJ1与Caloramatorsp.LSA2(AY770516)同源性最高,相似度为99%。滤纸降解试验显示,该菌能够单独有效地降解滤纸。该菌为革兰阴性菌,能够利用滤纸、微晶纤维素、羧甲基纤维素钠、秸秆、脱脂棉、木薯渣、木聚糖。此外,由酶谱分析可见,该菌能够大量地分泌胞外的木聚糖酶和羧甲基纤维素酶。其分泌的大量胞外木聚糖酶及羧甲基纤维素酶是该菌能够降解纤维素的主要原因。The paper is to introduce the results of our work in isolating a cellulolytic strain from a microbial consortium with highly efficient cellulolytic activity along with a brief preliminary analysis of its characteristic features. In our paper, we have adopted avicel and filter paper as the unique carbon source to enrich the cellulolytic microbes. We have thus isolated a thermophilic cellulolytic facultative anaerobic bacterium named FLJ1 with efficient filter paper degradation power. The cells of our isolated strain prove to be spore-forming bacterium in the straight shape with slightly curved rods in 0.2-0.4 μm×2-5 μm, with gram negative. Then we have made an analysis of its characteristic features with the help of 16S rRNA sequence, through the filter paper degradation test and zymogram test. The results of our morphological, biochemical and physiological assessment and phylogenetic tree construction indicate that the closest phylogenetic relative product is the Caloramator sp. LSA2 （AY770516） with 99% of sequential similarity. It has also been found that strain FLJ1 is an effective cellulolytic bacterium via the filter paper degradation test, in which the strain FLJ1 can help to degrade filter paper during the first three days and its degradation rate of the filter paper can be made to reach 46.25%. In addition, a large amount of sugar and volatile acid were likely to have resulted in the degradation process and tend to eventually inhibit it. Furthermore, the experimental results of ours demonstrate that strain FLJ1 can effectively degrade lignocellulosic substances, such as filter paper, avicel, carboxymethyl cellulose sodium, straw, absorbent cotton, cassava residues, and xylan. What is more, the zymogram analysis results also reveal that strain FLJ1 can secrete a large amount of extracellular xylanase and carboxymethyl cellulase（CMCase）. And, last of all, the isolated strain FLJ1 proves to belong to Caloramator sp. which is good at singly degrading the filter paper. The presence of extracellular f

关 键 词：微生物学 嗜热兼性厌氧菌 分离鉴定 滤纸降解 酶谱分析 

分 类 号：Q939.9[生物学—微生物学]