Identification of cellulolytic bacteria in soil by stable isotope probing
Identification of cellulolytic bacteria in soil by stable isotope probing
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DOI：
10.1111/j.1462-2920.2006.01182.x
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发表时间：
2007-03-01
影响因子：
5.1
通讯作者：
Berge, Odile
中科院分区：
文献类型：
--
作者：
Haichar, Feth el Zahar;Achouak, Wafa;Berge, Odile
植物残体是陆地生态系统中最大的有机碳物质，主要由纤维素组成。土壤微生物主要负责将这些碳转移到大气中，但它们的贡献并不准确。本研究的目的是确定积极参与纤维素降解的细菌种群，使用DNA稳定同位素探测（DNA-SIP）技术。C-13-纤维素由木醋杆菌产生，并在土壤中培养7、14、30和90天。从土壤中提取总DNA，C-13标记的（重）和未标记的（轻）DNA组分通过超离心分离，并通过细菌自动核糖体基因间间隔区分析（B-ARISA）和变性梯度凝胶电泳（DGGE）的特征分析活性细菌群落的结构。纤维素降解与重DNA产生的细菌群落结构的显着变化相关，导致新条带的出现和其他条带相对强度的增加，直到第30天。在第90天，大多数条带的相对强度降低。DGGE图谱中的10个条带的测序和系统发育分析表明，大多数序列与已知其降解纤维素的能力的生物或未培养的土壤细菌的序列密切相关。
Plant residues, mainly made up of cellulose, are the largest fraction of organic carbon material in terrestrial ecosystems. Soil microorganisms are mainly responsible for the transfer of this carbon to the atmosphere, but their contribution is not accurately known. The aim of the present study was to identify bacterial populations that are actively involved in cellulose degradation, using the DNA-stable isotope probing (DNA-SIP) technique. C-13-cellulose was produced by Acetobacter xylinus and incubated in soil for 7, 14, 30 and 90 days. Total DNA was extracted from the soil, the C-13-labelled (heavy) and unlabelled (light) DNA fractions were separated by ultracentrifugation, and the structure of active bacterial communities was analysed by bacterial-automated ribosomal intergenic spacer analysis (B-ARISA) and characterized with denaturing gradient gel electrophoresis (DGGE). Cellulose degradation was associated with significant changes in bacterial community structure issued from heavy DNA, leading to the appearance of new bands and increase in relative intensities of other bands until day 30. The majority of bands decreased in relative intensity at day 90. Sequencing and phylogenetic analysis of 10 of these bands in DGGE profiles indicated that most sequences were closely related to sequences from organisms known for their ability to degrade cellulose or to uncultured soil bacteria.