title: Microbial diversity of soil bacteria in agricultural field contaminated with heavy metals.
abstract: In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA directly extracted from the soil revealed 17 different bacterial types (genera and/or species). They included Polyangium spp., Sphingomonas spp., Variovorax spp., Hafina spp., Clostridia, Acidobacteria, the enterics and some uncultured strains. Microbes able to tolerate high concentrations of cadmium (500 micromol/L and above) were also isolated from the soil. These isolates included strains of Acinetobacter (strain CD06), Enterobacter sp. (strains CD01, CD03, CD04 and CD08) (similar strains also identified in culture-independent approach) and a strain of Stenotrophomonas sp. The results indicated that the species identified from direct analysis of 16S rDNA of the soil can be quite different from those strains obtained from enrichment cultures and the microbial activities for heavy metal resistance might be more appropriately addressed by the actual isolates.
authors.affiliation: Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Chung-Li, Taiwan 320, China. ccchien@saturn.yzu.edu.tw
authors.forename: Chihching
authors.initials: C
authors.lastname: Chien
authors.forename: Yumei
authors.initials: Y
authors.lastname: Kuo
authors.forename: Changchieh
authors.initials: C
authors.lastname: Chen
authors.forename: Chunwei
authors.initials: C
authors.lastname: Hung
authors.forename: Chihwei
authors.initials: C
authors.lastname: Yeh
authors.forename: Weijen
authors.initials: W
authors.lastname: Yeh
mesh_terms: D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D044822:Biodiversity; D002104:Cadmium / Q000032:analysis / Q000633:toxicity; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D008969:Molecular Sequence Data; D009231:Myxococcales / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D020578:Sphingomonas / Q000187:drug effects / Q000235:genetics / Q000254:growth & development
chemical_list: D004269:DNA, Bacterial; D019216:Metals, Heavy; D012336:RNA, Ribosomal, 16S; D012987:Soil; D002104:Cadmium