title: Seasonal and genotypic changes in escherichia coli phylogenetic groups in the Yeongsan River basin of South Korea.
abstract: 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.
authors.affiliation: School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
authors.forename: Jeonghwan
authors.initials: J
authors.lastname: Jang
authors.affiliation: School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
authors.forename: Doris Y W
authors.initials: DY
authors.lastname: Di
authors.affiliation: School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
authors.forename: Anna
authors.initials: A
authors.lastname: Lee
authors.affiliation: College of Molecular Life Sciences, Jeju National University, Jeju, Republic of Korea.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Unno
authors.affiliation: Department of Soil, Water and Climate, University of Minnesota, St. Paul, Minnesota, United States of America; BioTechnology Institute, University of Minnesota, St. Paul, Minnesota, United States of America.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Sadowsky
authors.affiliation: School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea; International Environmental Analysis and Education Center, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
authors.forename: Hor-Gil
authors.initials: HG
authors.lastname: Hur
mesh_terms: D016172:DNA Fingerprinting; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D005838:Genotype; D010802:Phylogeny; D056910:Republic of Korea; D045483:Rivers / Q000382:microbiology*; D012621:Seasons; D054323:Shiga-Toxigenic Escherichia coli / Q000378:metabolism