Nanoparticles can easily reach soil,water and foodstuffs. The zinc oxide nanoparticle (ZnONP), which is a type of nanoparticle with known antiviral/microbial properties used frequently in cosmetic UV protection products, can damage the cell membrane/wall complex in Saccharomyces cerevisiae after exposure. However, the capacity of hsp150, an o-mannosylated heat shock protein needed for the strength of the S. cerevisiae cell wall, to prevent ZnONP toxicity/genotoxicity has not been investigated before. In this study, HSP150 gene of S. cerevisiae cells was deleted and the effects on the toxicity caused by ZnONPs were investigated by MTT, cell wall/membrane damage analyses and zymolyase susceptibility test. In addition, the level of oxidative DNA damage was determined by 8-OHdG test in the HSP150 deficient cells (hsp150 Delta). IC50 values observed in hsp150 Delta cells were lower than the wild type cells. In addition, the lowest dose of ZnONPs (250 mu g/mL) was significant enough to damage the cellular integrity in hsp150 Delta cells and DNA damage levels observed in the hsp150 Delta cells exposed to the lowest dose of the nanoparticles were nearly 2.5 times higher than the wild type cells. Therefore, it can be concluded that the HSP150 gene is needed for the cellular protection against ZnONP toxicity and genotoxicity.

As a tetracycline antibiotic, the enrichment of doxycycline in soil seriously endangers agricultural cultivation and food security. Salvianolic acid B (SAB), as a natural product, has high antioxidant activity. We applied SAB and doxycycline (DOX) externally to Salvia miltiorrhiza seedlings, and measured the activities of total superoxide dismutase, peroxidase and catalase, as well as the accumulation of malondialdehyde, active oxygen and glutathione. It was found that SAB can participate in the DOX stress release of S. miltiorrhiza through the antioxidant system. We also analyzed the evolutionary relationship of multidrug and toxic compound extrusion (MATE) family proteins related to antibiotic transport in 50 representative evolutionary genomes, and revealed the potential binding ability of MATE and DOX through macromolecular docking. Finally, based on transcriptome and RT-qPCR analysis, we identified a novel gene SmMATE1, and found that it has a co-expression pattern with SmRAS and SmCYP98A14. Transgenic in tobacco, yeast and hairy root of S. miltiorrhiza revealed the important role of this new gene and SAB in synergistically releasing DOX stress damage, which provided a reference for natural product to alleviate the stress of antibiotics on plants, and also provided a theoretical basis for the development of new soil antibiotic sustained-release agents.