Lead sulfide nanoparticles increase cell wall chitin content and induce apoptosis in Saccharomyces cerevisiae.
Although there have been numerous studies on bacterial toxicity, the cytotoxicity of nanoparticles toward fungi remains poorly understood. We investigated the toxicity of various sizes of lead sulfide particles against the important model fungus, Saccharomyces cerevisiae. The smallest particle exerted the highest toxicity, inhibiting cell growth and decreasing cell viability, likely reflecting reduced sedimentation and persistent cell wall attack. In response to cell wall stress, S. cerevisiae showed an increase in the cell wall chitin content and the overexpression of FKS2 and PRM5, two genes of the cell wall integrity signaling pathway. Cell wall stress increased the concentration of intracellular reactive oxygen species, leading to mitochondrial dysfunction and cell apoptosis. The contribution of dissolved lead ions to the overall toxicity was negligible. These findings provide the first demonstration of the physiological protective response of a fungus toward nanoparticles, thereby contributing useful information to the assessment of the environmental impact of metal nanoparticles.
College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
Meiqing
M
Sun
Ministry of Education Key Laboratory of Molecular Microbiology and Technology, Department of Microbiology, College of Life Science, Nankai University, Tianjin 300071, China.
Qilin
Q
Yu
Affiliated High School of Nankai University, China.
Mengyuan
M
Hu
College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
Zhenwei
Z
Hao
College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address: zhangchengdong@nankai.edu.cn.
Chengdong
C
Zhang
Ministry of Education Key Laboratory of Molecular Microbiology and Technology, Department of Microbiology, College of Life Science, Nankai University, Tianjin 300071, China. Electronic address: nklimingchun@163.com.
Mingchun
M
Li
D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000235:genetics; D002473:Cell Wall / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D002686:Chitin / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D005964:Glucosyltransferases / Q000235:genetics; D007854:Lead / Q000633:toxicity*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008565:Membrane Proteins / Q000235:genetics; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D013440:Sulfides / Q000633:toxicity*
D008565:Membrane Proteins; D017382:Reactive Oxygen Species; D029701:Saccharomyces cerevisiae Proteins; D013440:Sulfides; D002686:Chitin; C018391:lead sulfide; D007854:Lead; D005964:Glucosyltransferases; C095724:GSC2 protein, S cerevisiae; D020169:Caspases; C456272:MCA1 protein, S cerevisiae
Apoptosis; Chitin; Lead sulfide nanoparticles; Toxicity; Yeast