School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
College of Molecular Life Sciences, Jeju National University, Jeju, Republic of Korea.
PLoS One. 2014 Jul 7;9(7):e100585. doi: 10.1371/journal.pone.0100585. eCollection 2014.
With 3,480 E. coli strains isolated from the Yeongsan River basin, South Korea, correlations between phylogenetic groups and horizontal fluorophore enhanced rep-PCR (HFERP) genotypes were examined, and environmental factors affecting E. coli phylogenetic groups in the river water were determined. Interestingly, multidimentional scaling (MDS) analyses based on HFERP DNA fingerprint data indicated that E. coli in phylogenetic groups A and B1 were uniquely clustered. Results of self-organized maps (SOMs) analyses also indicated that E. coli phylogenetic groups were seasonally affected by water temperature, with greater occurrences of phylogenetic groups A and B1 in low and high temperature seasons, respectively. The presence of E. coli in phylogenetic groups A and B1 were inversely related. Furthermore, redundancy analysis (RDA) revealed that phylogenetic group B1 correlated positively with temperature, strain diversity, and biochemical oxygen demand (BOD) but negatively with phylogenetic group A. Results of this study indicated that while E. coli strains could be clustered based on their genotypes and environment conditions, their phylogenetic groups did not change in relation to the same conditions. The distributional differences of phylogenetic groups among E. coli populations in different environments may be caused by different genomic adaptability and plasticity of E. coli strains belonging to each phylogenetic group. Although several previous studies have reported different E. coli ecological structures depending on their origins, this study is a first description of the specific environmental factors affecting E. coli phylogenetic groups in river water.
从韩国的梁山流域分离出 3480 株大肠杆菌菌株，研究了它们的进化群与水平荧光增强重复聚合酶链反应（HFERP）基因型之间的相关性，并确定了影响河水大肠杆菌进化群的环境因素。有趣的是，基于 HFERP DNA 指纹数据的多维尺度分析（MDS）表明，进化群 A 和 B1 的大肠杆菌独特地聚集在一起。自组织映射（SOM）分析的结果也表明，大肠杆菌进化群受水温的季节性影响，分别在低温和高温季节出现更多的进化群 A 和 B1。进化群 A 和 B1 中的大肠杆菌呈负相关。此外，冗余分析（RDA）表明，进化群 B1 与温度、菌株多样性和生化需氧量（BOD）呈正相关，但与进化群 A 呈负相关。本研究表明，虽然大肠杆菌菌株可以根据其基因型和环境条件进行聚类，但它们的进化群不会因相同的条件而发生变化。不同环境中大肠杆菌种群的进化群分布差异可能是由于属于每个进化群的大肠杆菌菌株具有不同的基因组适应性和可塑性所致。尽管以前的几项研究报告了不同的大肠杆菌生态结构取决于其起源，但本研究首次描述了影响河水中大肠杆菌进化群的具体环境因素。
