The microbial ecology of anaerobic cellulose degradation in municipal waste landfill sites: evidence of a role for fibrobacters.
The microbial ecology of anaerobic cellulose degradation in municipal waste landfill sites: evidence of a role for fibrobacters.
复制标题
DOI：
10.1111/j.1462-2920.2011.02688.x
复制
发表时间：
2012-04
影响因子：
5.1
通讯作者：
J. McDonald;James N. I. Houghton;D. J. Rooks;H. Allison;A. Mccarthy
中科院分区：
文献类型：
--
作者：
J. McDonald;James N. I. Houghton;D. J. Rooks;H. Allison;A. Mccarthy
纤维素被认为是生物圈中最丰富的有机聚合物，然而，尽管纤维素分解微生物在全球碳循环中发挥着重要作用，并作为生物技术的新型酶的潜在来源，但它们的身份和生态学尚未得到很好的确立。纤维素是填埋废物的主要成分，因此其降解是厌氧微生物分解过程的关键特征。在这里，我们通过PCR和定量PCR（qPCR）针对垃圾渗滤液中含有已知纤维素分解厌氧菌（纤维杆菌属细菌的成员，梭菌属I，III，IV和XIV的谱系，以及新美鞭菌的厌氧真菌）的一些分类群，并定殖纤维素“诱饵”。纤维杆菌属在几乎所有的渗滤液样品中均检测到梭菌群III、IV和XIV，其中梭菌群III和XIV的数量最多（分别占细菌16 S rRNA基因拷贝数的1-6%和1-17%）。构建了两个垃圾渗滤液微生态系统，以专门评估那些在原位定殖和降解纤维素基质的微生物群落。扫描电子显微镜（SEM）的殖民棉花揭示了广泛的纤维素降解的一个缩影，和纤维杆菌属。和梭菌簇III分别占生物膜中细菌16 S rRNA基因拷贝总数的29%和17%。在第二个微观世界中没有观察到可见的纤维素降解，这与梭菌簇III和纤维杆菌属的相对丰度可忽略不计相关。（≤ 0.1%），提供了最近在垃圾填埋场和其他非肠道环境中检测到的新型纤维杆菌原位定殖和降解纤维素底物的第一个证据。
Cellulose is reputedly the most abundant organic polymer in the biosphere, yet despite the fundamental role of cellulolytic microorganisms in global carbon cycling and as potential sources of novel enzymes for biotechnology, their identity and ecology is not well established. Cellulose is a major component of landfill waste and its degradation is therefore a key feature of the anaerobic microbial decomposition process. Here, we targeted a number of taxa containing known cellulolytic anaerobes (members of the bacterial genus Fibrobacter, lineages of Clostridium clusters I, III, IV and XIV, and anaerobic fungi of the Neocallimastigales) in landfill leachate and colonized cellulose 'baits' via PCR and quantitative PCR (qPCR). Fibrobacter spp. and Clostridium clusters III, IV and XIV were detected in almost all leachate samples and cluster III and XIV clostridia were the most abundant (1-6% and 1-17% of total bacterial 16S rRNA gene copies respectively). Two landfill leachate microcosms were constructed to specifically assess those microbial communities that colonize and degrade cellulose substrates in situ. Scanning electron microscopy (SEM) of colonized cotton revealed extensive cellulose degradation in one microcosm, and Fibrobacter spp. and Clostridium cluster III represented 29% and 17%, respectively, of total bacterial 16S rRNA gene copies in the biofilm. Visible cellulose degradation was not observed in the second microcosm, and this correlated with negligible relative abundances of Clostridium cluster III and Fibrobacter spp. (≤ 0.1%), providing the first evidence that the novel fibrobacters recently detected in landfill sites and other non-gut environments colonize and degrade cellulose substrates in situ.