Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), ES-08003 Barcelona, Catalunya, Spain.
Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), ES-08003 Barcelona, Catalunya, Spain.
Syst Appl Microbiol. 2014 Feb;37(1):68-78. doi: 10.1016/j.syapm.2013.08.006. Epub 2013 Nov 1.
The abundance and structure of Bacteroidetes populations at diverse temporal and spatial scales were investigated in the Northwestern Mediterranean Sea. At a temporal scale, their relative abundance exhibited a marked seasonality, since it was higher in spring and decreased in winter. Similarly, Bacteroidetes community structure encompassed three main groups (winter, spring and summer-fall), which mimicked global bacterioplankton seasonality. At the spatial scale, relative abundances were similar in all surface samples along an inshore-offshore transect, but they decreased with depth. Analysis of the community structure identified four markedly different groups mostly related to different depths. Interestingly, seasonal changes in abundance and community structure were not synchronized. Furthermore, richness was higher when Bacteroidetes were less abundant. The variability of Bacteroidetes contributions to community structure in the temporal and spatial scales was correlated with different environmental factors: day length was the most important factor at the temporal scale, and salinity at the spatial scale. The community composition in terms of phylotypes changed significantly over time and along the depth gradients, but season or depth-specific phylogenetic clusters were not identified. Delineation of coherent Bacteroidetes sub-clusters should help to uncover higher resolution patterns within Bacteroidetes, and explore associations with environmental and biological variables.
本研究调查了西北地中海海域不同时空尺度下拟杆菌门种群的丰度和结构。在时间尺度上，它们的相对丰度具有明显的季节性，春季较高，冬季较低。同样，拟杆菌门群落结构包含三个主要群体（冬季、春季和夏季-秋季），这与全球浮游细菌的季节性相似。在空间尺度上，沿岸-近海断面的所有表层样品中的相对丰度相似，但随深度降低。群落结构分析确定了四个明显不同的组，主要与不同的深度有关。有趣的是，丰度和群落结构的季节性变化不同步。此外，当拟杆菌门丰度较低时，丰富度更高。在时间和空间尺度上，拟杆菌门对群落结构的贡献的可变性与不同的环境因素有关：在时间尺度上，日长是最重要的因素，而在空间尺度上，盐度是最重要的因素。在时间和深度梯度上，以 phylotype 表示的群落组成发生了显著变化，但没有确定特定季节或深度的系统发育聚类。对一致的拟杆菌亚群进行描绘有助于揭示拟杆菌门内更高分辨率的模式，并探索与环境和生物变量的关联。
