title: Cellular surface characteristics of Saccharomyces cerevisiae before and after Ag(I) biosorption.
abstract: The surface characteristics of Saccharomyces cerevisiae before and after Ag(I) biosorption were investigated by comprehensively using the scanning electron microscopy with the energy-dispersive X-ray analysis (SEM-EDX), the transmission electron microscopy with energy-dispersive X-ray analysis (TEM-EDX) and atomic force microscopy (AFM). The results showed that cell surface elements, surface topography and three-dimensional structures of S. cerevisiae changed after Ag(I) biosorption. SEM observation indicated that the appearances of Ag-adsorbed cells varied with initial Ag(I) concentration and contact time. TEM images observed Ag(I)-containing precipitates. AFM observation indicated that cells became smaller, and cell surface became smoother. The results of SEM-EDX, TEM-EDX, AFM and biosorption illustrated that Ag(I) was adsorbed onto the cell surface by covalent binding and ionic binding. P-, S- and O-containing groups on cell surface possibly contributed to the binding silver ions, and the N-containing components released from cells also probably contributed to Ag(I) biosorption.
authors: Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China.
authors: Can
authors: C
authors: Chen
authors: College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
authors: Donghui
authors: D
authors: Wen
authors: Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China; Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084, PR China. Electronic address: wangjl@tsinghua.edu.cn.
authors: Jianlong
authors: J
authors: Wang
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental / Q000187:drug effects; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure; D012834:Silver / Q000494:pharmacology*; D013052:Spectrometry, X-Ray Emission
chemical_list: D012834:Silver
keywords: Biosorption; Cellular surface; Saccharomyces cerevisiae; Silver