Characterization of copper-resistant bacteria and assessment of bacterial communities in rhizosphere soils of copper-tolerant plants

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• 作者：Lin Yan He ; Yan Feng Zhang ; Hai Yan Ma ; Le Ni Su ; Zhao Jin Chen ; Qing Ya Wang ; Meng Qian ; Xia Fang Sheng
• 关键词：Heavy metal-resistant rhizobacteria ; DGGE ; Bacterial community ; Copper-tolerant plants ; Copper mining wasteland
• 刊名：Applied Soil Ecology
• 出版年：2010
• 出版时间：January 2010
• 年：2010
• 卷：44
• 期：1
• 页码：49-55
• 全文大小：332 K

文摘

Thirteen copper-resistant bacteria were isolated from copper-tolerant plant species growing on a copper mine wasteland. The isolates were identified by 16S rRNA gene sequence analysis and characterized by their resistance to heavy metals and plant growth-promoting characteristics. The assessment of the bacterial communities in the rhizosphere soils of copper-tolerant plants was measured as bands in denaturing gradient gel electrophoresis (DGGE) obtained directly from rhizosphere soil DNA extracts. The isolates were found to exhibit different multiple heavy metal resistance characteristics. Strains SZY6, YJ7 and JYC17 were found to produce indole acetic acid (IAA), siderophore, 1-aminocyclopropane-1-carboxylate (ACC) deaminase or to solubilize phosphate. Root elongation assay conducted on rape under gnotobiotic conditions with strains MT16, JYC17, SZY6, GZC24, and YJ7 demonstrated increase (from 16 to 41 % ) in root elongation of inoculated rape seedlings compared to the control plants. In the rhizosphere soil samples the DGGE profiles of the direct DNA extracts were similar. The DGGE profiles indicated that there was no significant correlation between the concentration of available copper in the rhizosphere soils and the number of the visible bands in the DGGE pattern.