title: Extracellular polymeric substances dependence of surface interactions of Bacillus subtilis with Cd2+and Pb2+: An investigation combined with surface plasmon resonance and infrared spectra.
abstract: Microbial extracellular polymeric substances (EPS) play an important role in resisting the shock load of toxic contaminants to microbial aggregates. In order to investigate the surface interaction process of bacteria with heavy metals, in this work, the kinetics and affinity of heavy metal (CdCl2and PbCl2) binding on Bacillus subtilis with EPS and without EPS were determined using in situ surface plasmon resonance. The binding mechanism between bacteria (with EPS and without EPS) and heavy metals was probed using Fourier-transform infrared spectra. The effect of heavy metals on aggregations of microbial cells with EPS and without EPS was investigated. The results showed that both the binding of Pb2+and Cd2+to bacteria with EPS had a similar kinetics process, however Pb2+bound to bacterial surface without EPS more firmly compared with Cd2+. From our results we theorized that heavy metals changed the protein secondary structures of bacteria without EPS protection, that EPS reduced the influence of heavy metals on microbial aggregation, and that Pb2+inhibited cell aggregation more easily compared with Cd2+in the absence of EPS.
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China. Electronic address: ypchen@cigit.ac.cn.
authors.forename: You-Peng
authors.initials: YP
authors.lastname: Chen
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China.
authors.forename: Meng-Wen
authors.initials: MW
authors.lastname: Peng
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
authors.forename: Jin-Song
authors.initials: JS
authors.lastname: Guo
authors.affiliation: Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China. Electronic address: shenyu@cigit.ac.cn.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yan
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China.
authors.forename: Qiu-Hong
authors.initials: QH
authors.lastname: Zhou
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
mesh_terms: D000327:Adsorption; D001412:Bacillus subtilis / Q000737:chemistry / Q000187:drug effects* / Q000254:growth & development; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D019256:Cadmium Chloride / Q000037:antagonists & inhibitors* / Q000633:toxicity; D002413:Cations, Divalent; D003470:Culture Media / Q000737:chemistry; D006812:Humic Substances / Q000032:analysis*; D007700:Kinetics; D007854:Lead / Q000633:toxicity; D011135:Polysaccharides, Bacterial / Q000302:isolation & purification / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D001426:Bacterial Proteins; D002413:Cations, Divalent; D003470:Culture Media; D006812:Humic Substances; D011135:Polysaccharides, Bacterial; D007854:Lead; C029891:lead chloride; D019256:Cadmium Chloride
keywords: Aggregation; Binding; Extracellular polymeric substances; Heavy metals; Surface plasmon resonance