title: Mechanism of H₂O₂-induced oxidative stress regulating viability and biocontrol ability of Rhodotorula glutinis.
abstract: The use of antagonistic yeasts to control postharvest pathogens is a promising alternative to fungicides. The effectiveness of the antagonists against fungal pathogens is greatly dependent on their viability, which is usually mediated by reactive oxygen species (ROS). Here, we investigated the effects of H₂O₂-induced oxidative stress on the viability and biocontrol efficacy of Rhodotorula glutinis and, using flow cytometric analysis, observed the changes of ROS accumulation and apoptosis in the yeast cells with or without H₂O₂ treatment. We found that the viability of R. glutinis decreased in a time- and dose-dependent manner under H₂O₂-induced oxidative stress. Compared to the control, yeast cells exposed to oxidative stress exhibited more accumulation of ROS and higher levels of protein oxidative damage, but showed lower efficacy for biocontrol of Penicillium expansum causing blue mold rot on peach fruit. The results indicate that apoptosis is a main cause of the cell viability loss in R. glutinis, which is attributed to ROS accumulation under oxidative stress. These findings offer a plausible explanation that oxidative stress affects biocontrol efficacy of R. glutinis via regulating its viability and cell apoptosis.
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Boqiang
authors.initials: B
authors.lastname: Li
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Guozheng
authors.initials: G
authors.lastname: Qin
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China. Electronic address: tsp@ibcas.ac.cn.
authors.forename: Shiping
authors.initials: S
authors.lastname: Tian
mesh_terms: D000898:Antibiosis / Q000187:drug effects; D017209:Apoptosis / Q000187:drug effects; D005516:Food Microbiology; D005659:Fungicides, Industrial / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D050296:Microbial Viability; D018384:Oxidative Stress / Q000187:drug effects*; D010407:Penicillium / Q000254:growth & development; D027861:Prunus / Q000382:microbiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012248:Rhodotorula / Q000187:drug effects* / Q000502:physiology*
chemical_list: D005659:Fungicides, Industrial; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide
keywords: Apoptosis; Biocontrol efficacy; Oxidative stress; ROS; Rhodotorula glutinis