School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; Key Laboratory of Agro-Environment in the Tropics, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, PR China.
School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China.
Chemosphere. 2014 Aug;109:134-42. doi: 10.1016/j.chemosphere.2014.01.066. Epub 2014 Feb 18.
In an effort to explore the protective mechanism of growing Bacillus cereus RC-1 against the toxicity of different Cd(II) concentrations, bacterial growth, cadmium consumption, surface interactions and intra- and extra-cellular Cd(II) contents were examined. Cellular morphology and growth were evidently affected by the initial metal concentrations above 20 mg L(-1), according to the analysis of SEM, AFM, TEM and UV spectrophotometer. Surface complexation and electrostatic attraction played an important role in the different Cd(II) concentrations, as determined by the FTIR and Zeta potential analysis. Intracellular accumulation was the predominant mechanism in culture with lower metal concentrations (below 20 mg L(-1)), but was overshadowed by extracellular adsorption at higher concentrations. This suggested that the growing cells might employ one dominant mechanism at lower concentrations and then shift to another at higher concentrations. These results suggest options could be exploited for bioremediation of aqueous solution in which the Cd(II) concentration is less than 20 mg L(-1).
为了探索生长的蜡状芽孢杆菌 RC-1 对不同浓度 Cd(II)毒性的保护机制，研究了细菌生长、镉消耗、表面相互作用以及细胞内外 Cd(II)含量。根据 SEM、AFM、TEM 和紫外分光光度计的分析，当初始金属浓度高于 20 mg L(-1)时，细胞形态和生长明显受到影响。通过 FTIR 和 Zeta 电位分析表明，表面络合和静电吸引在不同 Cd(II)浓度下起着重要作用。在较低金属浓度（低于 20 mg L(-1))下，细胞内积累是主要的机制，但在较高浓度下，细胞外吸附占主导地位。这表明在较低浓度下，生长细胞可能采用一种主要的机制，而在较高浓度下则采用另一种机制。这些结果表明，可以利用这些方法来修复 Cd(II)浓度低于 20 mg L(-1)的水溶液。
