Guo Shanshan, Yao Yuan, Zuo Lei, Shi Wenjin, Gao Ni, Xu Heng
Key Laboratory of Bio-Resources and Eco-Environment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, Sichuan, China.
J Basic Microbiol. 2016 Jan;56(1):36-43. doi: 10.1002/jobm.201500451. Epub 2015 Sep 28.
Nitric oxide (NO) is considered as a signaling molecule involved in regulation of diverse physiological processes and stress responses in animals and plants. However, whether NO regulates fungal, particularly edible fungi, response to heavy metal stresses, is unknown. This study investigated the effect of nitric oxide on biological responses of mycelia of Ganoderma lucidum to cadmium (Cd) toxicity. Exposure of Ganoderma lucidum to Cd (400 µM) triggered production of H2O2 and O2(-) in the mycelia and further induced lipid peroxidation as well as sharply decrease of fresh biomass. However, such an effect can be reversed by exogenous supply of NO. Mycelia treated with 100 µM SNP accumulated less H2O2, O2(-), thiobarbituric acid reactive substances (TBARS), and fresh biomass of this treatment was improved. Treatment with SNP significantly increased activities of antioxidant enzyme (peroxidase and catalase) to resist Cd stress. Meanwhile, NO-mediated alleviation of Cd toxicity was closely related to the accumulated proline as well as reduced Cd accumulation. These results suggested that NO plays a crucial role in preventing the mycelia of Ganoderma lucidum from Cd toxicity.
一氧化氮（NO）被认为是一种信号分子，参与调节动植物的多种生理过程和应激反应。然而，NO是否调节真菌，特别是食用菌对重金属胁迫的反应尚不清楚。本研究调查了一氧化氮对灵芝菌丝体对镉（Cd）毒性的生物学反应的影响。灵芝暴露于Cd（400 µM）会引发菌丝体中H2O2和O2(-)的产生，并进一步诱导脂质过氧化以及鲜重急剧下降。然而，这种影响可以通过外源供应NO来逆转。用100 µM SNP处理的菌丝体积累的H2O2、O2(-)、硫代巴比妥酸反应性物质（TBARS）较少，并且该处理的鲜重有所改善。用SNP处理显著提高了抗氧化酶（过氧化物酶和过氧化氢酶）的活性以抵抗Cd胁迫。同时，NO介导的Cd毒性缓解与脯氨酸积累以及Cd积累减少密切相关。这些结果表明，NO在防止灵芝菌丝体受到Cd毒性方面起着关键作用。
