Centre of Advanced Studies of Blanes, CEAB-CSIC, Spanish Council for Scientific Research, Accés Cala St. Francesc 14, E-17300, Blanes, Spain.
Environ Microbiol Rep. 2014 Apr;6(2):145-51. doi: 10.1111/1758-2229.12142. Epub 2014 Jan 19.
The phylogenetic composition of freshwater anoxygenic photoheterotrophs (APs) has been poorly investigated as compared with their marine counterparts. In this study, we explored a set of ultraoligotrophic cold high mountain lakes (Central Pyrenees, Spain) by both pufM gene denaturing gradient gel electrophoresis fingerprinting, and cloning and sequencing of selected lakes samples. Different ranges of limnological and physico-chemical values were explored as environmental drivers of APs richness and composition. We did not observe significant relationships between richness/diversity of pufM and any of the limnological characteristics measured or trophic status, but a negative correlation with ammonia concentration. Conductivity, pH and nitrate concentration were significantly related to changes in APs community composition, whereas lake area, altitude, temperature and trophic status did not. Most of the sequences (> 85%) had the pufM sequences of Limnohabitans (Betaproteobacteria) as the closest relative in databases, whereas less abundant clones were more closely related to Rhodobacter, Sulfitobacter and Brevundimonas (Alphaproteobacteria), in agreement with 16S rRNA gene sequences previously found in the area. Congregibacter-like Gammaproteobacteria were not detected. Comparison with available studies in inland waters showed taxonomic partitioning along salinity gradients, and Congregibacter-like sequences restricted to high saline conditions in continental water bodies.
与海洋相比，淡水乏氧光合作用细菌（APs）的系统发育组成研究甚少。本研究通过 pufM 基因变性梯度凝胶电泳指纹图谱分析和选定湖泊样本的克隆和测序，对一组超寡营养冷高山湖泊（西班牙比利牛斯山脉中部）进行了研究。探讨了不同范围的湖泊学和物理化学值作为 APs 丰富度和组成的环境驱动因素。我们没有观察到 pufM 的丰富度/多样性与任何测量的湖泊特征或营养状态之间存在显著关系，但与氨浓度呈负相关。电导率、pH 值和硝酸盐浓度与 APs 群落组成的变化显著相关，而湖泊面积、海拔、温度和营养状态则没有。大多数序列（>85%）与数据库中 Limnohabitans（β变形菌）的 pufM 序列最接近，而较少的克隆与 Rhodobacter、Sulfitobacter 和 Brevundimonas（α变形菌）的 pufM 序列更接近，这与该地区先前发现的 16S rRNA 基因序列一致。未检测到类似 Congregibacter 的γ变形菌。与内陆水域的现有研究相比，显示出沿盐度梯度的分类分区，而类似 Congregibacter 的序列仅限于大陆水体的高盐条件。
