Selective stimulation in a natural community of methane oxidizing bacteria: Effects of copper on pmoA transcription and activity
Selective stimulation in a natural community of methane oxidizing bacteria: Effects of copper on pmoA transcription and activity
复制标题
DOI：
10.1016/j.soilbio.2013.05.027
复制
发表时间：
2013-10
影响因子：
9.7
通讯作者：
A. Ho;C. Lüke;Andreas Reim;P. Frenzel
中科院分区：
文献类型：
--
作者：
A. Ho;C. Lüke;Andreas Reim;P. Frenzel
铜是一种必需元素，但往往不易被微生物利用，可能导致原位铜限制。在大多数甲烷氧化细菌（甲烷氧化菌）中，含铜的膜结合甲烷单加氧酶（pMMO）催化甲烷氧化的第一步。本研究采用基因芯片技术，在DNA和mRNA水平上研究了稻田土壤中甲烷氧化活性对铜添加的响应，测定了稻田土壤中甲烷氧化速率和pmoA多样性（编码pMMO亚基的基因）的变化。使用转录本（mRNA）作为代表的分类特异性活动，我们发现了一个明确的分离整体（DNA）和活性（mRNA）社区，后者是由Ia型甲烷氧化菌为主。铜的添加瞬时刺激甲烷吸收。这种刺激与甲基八叠球菌相关转录物的变化相关，从甲基八叠球菌转变为尚未培养的甲基八叠球菌。总之，我们证明了土壤中铜的限制，但在一定程度上仍然允许pmoA表达。分类群特异性的反应表明甲烷营养菌之间的细尺度生态位分化，与Methylobacter和Methylosarcinare立即采取行动铜修正案。
Copper is an essential element, but often not readily available to microorganisms potentially causing copper limitationin situ. In most methane oxidizing bacteria (methanotrophs), the copper-containing membrane bound methane monooxygenase (pMMO) catalyzes the first step in methane oxidation. We focused on the response of methanotrophic activity to a copper amendment in a rice paddy soil, measuring methane oxidation rates and following changes ofpmoAdiversity (a gene encoding for a subunit of the pMMO) both at DNA and mRNA level with a diagnostic microarray. Using transcripts (mRNA) as a proxy for taxon-specific activity, we found a clear separation between overall (DNA) and active (mRNA) community, the latter being dominated by type Ia methanotrophs. Copper addition transiently stimulated methane uptake. This stimulation correlated to a change withinMethylosarcina-related transcripts shifting fromMethylosarcina quisquiliarumto a yet uncultivatedMethylosarcinasp. Overall, we demonstrate copper limitation in a soil, but to an extent that still allowedpmoAexpression. The taxon-specific response suggests a fine-scale niche differentiation between methanotrophs, withMethylobacterandMethylosarcinareacting immediately to a copper amendment.