复合菌系降解纤维素过程中微生物群落结构的变化  

Change of bacterial community structure during cellulose degradation by the microbial consortium

作　　者：艾士奇 赵一全 孙志远 高亚梅 晏磊 唐鸿志[2] 王伟东 Shiqi Ai;Yiquan Zhao;Zhiyuan Sun;Yamei Gao;Lei Yan;Hongzhi Tang;Weidong Wang(Heilongjiang Provincial Engineering Technology Research Center of Straws Resources Utilization,Heilongjiang Provincial Key Laboratory of Environmental Microbiology and Recycling of Agro-Waste in Cold Region,College of Life Science and Biotechnology,Heilongjiang Bayi Agricultural University,Daqing 163319,Heilongiiang,China;State Key Laboratory of Microbial Metabolism,School of Life Sciences and Biotechnology,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]黑龙江八一农垦大学生命科学技术学院黑龙江省寒区环境微生物与农业废弃物资源化利用重点实验室黑龙江省秸秆资源化利用工程技术研究中心,黑龙江大庆163319 [2]上海交通大学生命科学技术学院微生物代谢国家重点实验室,上海200240

出　　处：《生物工程学报》2018年第11期1794-1808,共15页Chinese Journal of Biotechnology

基　　金：国家自然科学基金(No.31270536);中央财政引导地方科技发展专项(No.ZY16A06-02);黑龙江省自然科学基金(No.2D2018005);黑龙江省重点实验室开放基金(No.201703);黑龙江八一农垦大学研究生创新科研项目(No.YJSCX2017-Y70)资助~~

摘　　要：为明确高效纤维素降解复合菌系降解过程中微生物群落结构的变化规律及关键的降解功能菌,利用该复合菌系对滤纸和稻秆进行生物处理,通过底物降解、微生物生长量、发酵液pH的变化情况,选择不同降解时期复合菌系提取的总DNA进行细菌16S rRNA基因扩增子高通量测序。通过分解特性试验确定在接种后培养第12、72、168 h分别作为降解初期、高峰期、末期。该复合菌系分别主要由1个门、2个纲、2个目、7个科、11个属组成。随着降解的进行,短芽胞杆菌属Brevibacillus、喜热菌属Caloramator的相对丰度逐渐降低;梭菌属Clostridium、芽胞杆菌属Bacillus、地芽胞杆菌属Geobacillus、柯恩氏菌属Cohnella的相对丰度逐渐升高;解脲芽胞杆菌属Ureibacillus、泰氏菌属Tissierella、刺尾鱼菌属Epulopiscium在降解高峰期时相对丰度最高;各时期类芽胞杆菌属Paenibacillus、瘤胃球菌属Ruminococcus的相对丰度无明显变化。上述11个主要菌属均属于厚壁菌门,具有嗜热、耐热、适应广泛pH、降解纤维素或半纤维素的特性。好氧型细菌是降解初期的主要优势功能菌,到中后期厌氧型细菌逐渐增多,并逐步取代好氧型细菌成为降解纤维素的主要细菌。In order to clarify dynamic change of microbial community composition and to identify key functional bacteria in the cellulose degradation consortium, we studied several aspects of the biodegradation of filter papers and rice straws by the microbial consortium, the change of substrate degradation, microbial biomass and pH of fermentation broth. We extracted total DNA of the microbial consortium in different degradation stages for high-throughput sequencing of amplicons of bacterial 16S rRNA genes. Based on the decomposition characteristics test, we defined the 12th, 72nd and 168th hours after inoculation as the initial stage, peak stage and end stage of degradation, respectively. The microbial consortium was mainly composed of 1 phylum, 2 classes, 2 orders, 7 families and 11 genera. With cellulose degradation, bacteria in the consortium showed different growth trends. The relative abundance of Brevibacillus and Caloramator decreased gradually. The relative abundance of Clostridium, Bacillus, Geobacillus and Cohnella increased gradually. The relative abundance of Ureibacillus, Tissierella, Epulopiscium was the highest in peak stage. The relative abundance of Paenibacillus and Ruminococcus did not change obviously in each stage. Above-mentioned 11 main genera all belonged to Firmicutes, which are thermophilic, broad pH adaptable and cellulose or hemicellulose degradable. During cellulose degradation by the microbial consortium, aerobic bacteria were dominant functional bacteria in the initial stage. However, the relative abundance of anaerobic bacteria increased gradually in middle and end stage, and replaced aerobic bacteria to become main bacteria to degrade cellulose.

关 键 词：纤维素 复合菌系 降解 微生物多样性 

分 类 号：X172[环境科学与工程—环境科学]