Adhesion and internalization of functionalized polystyrene latex nanoparticles toward the yeast Saccharomyces cerevisiae

Abstract

a b s t r a c tThe toxicity and the internalization, adhesion, and dispersion behavior of manufactured polystyrene latex (PSL) nanoparticles (nominal diameter: 50 nm) with various functional groups toward the yeast Saccharomyces cerevisiae (which was applied as a model eukaryote) were examined using the colony count method, and microscopic observations. The colony count tests suggested that PSL nanoparticles with a negative surface charge showed little or no toxicity toward the yeast. In contrast, PSL nanoparticles with an amine functional group and a positive surface charge (p-Amine) displayed a high toxicity in 5 mM NaCl. However, the yeast cells were mostly unharmed by the p-Amine in 154 mM NaCl, results that were quite different from the toxicological effects observed when Escherichia coli was used as a model prokaryote. Confocal and atomic force microscopies indicated that in 5 mM NaCl, the p-Amine nanoparticles entirely covered the surface of the yeast, and cell death occurred; in contrast, in 154 mM NaCl, the pAmine nanoparticles were internalized via endocytosis, and cell death did not occur.

Cytotoxicity and behavior of polystyrene latex nanoparticles to budding yeast

“…1); similar results were reported in Ref. [16]. In an isotonic medium of 27.8 mM glucose aqueous solution, the yeast cells were covered with pA50 or pA100 NPs ( Fig.…”

“…Prescianotto-Baschong and Riezman mentioned that positively charged nanogold could be entrapped in yeast spheroplasts whose cell walls had been almost completely removed [14]. Interestingly, the authors [15,16] demonstrated that the uptake of endocytosis-like NPs by live budding yeast cells could be directly observed using confocal laser scanning microscopy (CLSM) in time-lapse mode when exposed to positively charged amine-modified polystyrene latex (PSL) NPs (diameter ≤100 nm) dispersed in physiological aqueous saline (154 mM NaCl). Conversely, in lower ionic strength aqueous NaCl solution, the NPs covered the budding yeast cell surface, consequently leading to cell death.…”

“…Yeast cells exposed to (A) pA50 and (B) pA100. The data in 5 and 154 mM NaCl were taken from Refs [15,16]…”

Microplastics as an emerging threat to terrestrial ecosystems

“… : Microplastics as trigger of combined physical or chemical‐like effects. Soil biogeochemistry related to agricultural mulching (Steinmetz et al., ), ingestion by terrestrial and continental birds (Gil‐Delgado et al., ; Holland et al., ; Zhao et al., ), reduction in growth of earthworms (Lwanga et al., ), lethal toxicity to fungi (Miyazaki et al., , ; Nomura et al., ), mammal lung inflammation (Hamoir et al., ; Oberdorster, ; Schmid & Stoeger, ) and broad cytotoxicity (Forte et al., ; Kato et al., ) of nanoplastics [Colour figure can be viewed at wileyonlinelibrary.com]…”

“…Nanoplastics externally adsorbed to cells might still cause toxicity by disrupting several membrane processes essential to the intracellular homeostasis of the exposed organism. Amino terminated polystyrene beads (50 nm) could strongly adhere to cells causing high toxicity at concentrations around 10 mg/L (Miyazaki et al., ). Conversely, carboxyl terminated polystyrene particles (50 nm) did not enter eukaryotic cells ( S. cerevisiae ), which had little effects on the growth rate at up to 80 mg/L after 1 h exposure (Miyazaki et al., ).…”