CNRS, UMR7621, Laboratoire d'Océanographie Biologique de Banyuls, Banyuls-sur-Mer, France.
FEMS Microbiol Lett. 2009 Oct;299(1):9-21. doi: 10.1111/j.1574-6968.2009.01694.x. Epub 2009 Jun 22.
The structure of the total and metabolically active communities of attached and free-living bacteria were analysed in the euphotic zone in the NW Mediterranean Sea with the use of DNA- and RNA-derived capillary electrophoresis single-strand conformation polymorphism fingerprinting. More than half (between 52% and 69%) of the DNA-derived operational taxonomic units (OTUs) were common in both attached and free-living fractions in the euphotic layer, suggesting an exchange or co-occurrence between them. However, analysis targeting 16S rRNA showed that only some of them were found in the dominant active bacterial pool. Especially at the deep chlorophyll maximum, less than half of the attached bacterial populations were found to be active, with regard to the high proportion of OTUs present at the DNA level, but not at the RNA level. These results suggest that even if colonization on and detachment of particles appear to be ubiquitous, most of the particulate organic carbon remineralization appeared to be mediated by a rather low number of dominant active OTUs specialized in exploiting such specific microenvironment.
利用 DNA 和 RNA 衍生的毛细管电泳单链构象多态性指纹分析，研究了西北地中海透光层中附着菌和自由生活菌的总群和代谢活性群的结构。超过一半（52%至 69%）的 DNA 衍生操作分类单元（OTU）在透光层的附着和自由生活部分中是共同的，表明它们之间存在交换或共存。然而，针对 16S rRNA 的分析表明，只有其中一些存在于优势活性细菌库中。特别是在深叶绿素最大值处，只有不到一半的附着细菌种群被发现具有活性，尽管 DNA 水平上存在大量 OTU，但在 RNA 水平上却没有。这些结果表明，即使在颗粒上的定植和脱落似乎无处不在的情况下，大部分颗粒有机碳的再矿化似乎是由少数专门利用这种特定微环境的优势活性 OTU 介导的。
