title: Metagenomic insights into evolution of a heavy metal-contaminated groundwater microbial community.
abstract: Understanding adaptation of biological communities to environmental change is a central issue in ecology and evolution. Metagenomic analysis of a stressed groundwater microbial community reveals that prolonged exposure to high concentrations of heavy metals, nitric acid and organic solvents ( approximately 50 years) has resulted in a massive decrease in species and allelic diversity as well as a significant loss of metabolic diversity. Although the surviving microbial community possesses all metabolic pathways necessary for survival and growth in such an extreme environment, its structure is very simple, primarily composed of clonal denitrifying gamma- and beta-proteobacterial populations. The resulting community is overabundant in key genes conferring resistance to specific stresses including nitrate, heavy metals and acetone. Evolutionary analysis indicates that lateral gene transfer could have a key function in rapid response and adaptation to environmental contamination. The results presented in this study have important implications in understanding, assessing and predicting the impacts of human-induced activities on microbial communities ranging from human health to agriculture to environmental management, and their responses to environmental changes.
authors.affiliation: Department of Botany and Microbiology, University of Oklahoma, Norman, OK, USA.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Hemme
authors.forename: Ye
authors.initials: Y
authors.lastname: Deng
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Gentry
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Fields
authors.forename: Liyou
authors.initials: L
authors.lastname: Wu
authors.forename: Soumitra
authors.initials: S
authors.lastname: Barua
authors.forename: Kerrie
authors.initials: K
authors.lastname: Barry
authors.forename: Susannah G
authors.initials: SG
authors.lastname: Tringe
authors.forename: David B
authors.initials: DB
authors.lastname: Watson
authors.forename: Zhili
authors.initials: Z
authors.lastname: He
authors.forename: Terry C
authors.initials: TC
authors.lastname: Hazen
authors.forename: James M
authors.initials: JM
authors.lastname: Tiedje
authors.forename: Edward M
authors.initials: EM
authors.lastname: Rubin
authors.forename: Jizhong
authors.initials: J
authors.lastname: Zhou
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D044822:Biodiversity; D005618:Fresh Water / Q000382:microbiology*; D006801:Humans; D056186:Metagenomics; D019216:Metals, Heavy / Q000633:toxicity; D017942:Nitric Acid / Q000633:toxicity; D009930:Organic Chemicals / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D019216:Metals, Heavy; D009930:Organic Chemicals; D014874:Water Pollutants, Chemical; D017942:Nitric Acid