Yue Zonghao, Chen Yanjuan, Chen Can, Ma Keshi, Tian Erli, Wang Ying, Liu Hongzhan, Sun Zhongke
College of Life Sciences and Agronomy, Zhoukou Normal University, Zhoukou 466001, China.
School of Mechanical and Electrical Engineering, Zhoukou Normal University, Zhoukou 466001, China.
J Hazard Mater. 2021 Mar 5;405:124272. doi: 10.1016/j.jhazmat.2020.124272. Epub 2020 Oct 13.
Soil copper (Cu) pollution severely stunts crops growth and limits sustainable agri-food production. Many microbes are widely used for remediation of polluted soil, including Cu pollution. In this study, the potential of an endophytic Bacillus altitudinis WR10 to protect wheat from Cu stress and the molecular mechanisms were investigated using hydroponic model. The Cu resistance assay showed B. altitudinis WR10 can resist up to 2 mM Cu and remove about 74% Cu in medium after 24 h of fermentation. Co-culture study demonstrated WR10 increased roots length and dry weight in wheat seedlings under 50 μM Cu. These results indicated that WR10 was a Cu-resistant strain and reduced Cu toxicity in wheat. Transcriptome data and biochemical tests of wheat roots indicated that WR10 alleviated Cu toxicity through enhancing peroxidases (PODs) gene expression and activity to remove excess hydrogen peroxide (HO) and down-regulating glutathione S-transferases (GSTs) to increase glutathione (GSH) level. Moreover, enrichment and pathway analysis indicated WR10 regulated the expression of genes involved in phenylpropanoid biosynthesis, which may improve phenolic acids accumulation for protecting plant cells from Cu toxicity. Overall, this study revealed that B. altitudinis WR10 alleviated Cu toxicity in wheat via augmenting reactive oxygen species scavenging and phenylpropanoid biosynthesis.
土壤铜（Cu）污染严重阻碍作物生长，限制了农业食品的可持续生产。许多微生物被广泛用于污染土壤的修复，包括铜污染土壤的修复。在本研究中，利用水培模型研究了内生高海拔芽孢杆菌WR10保护小麦免受铜胁迫的潜力及其分子机制。铜抗性试验表明，高海拔芽孢杆菌WR10能够耐受高达2 mM的铜，发酵24小时后可去除培养基中约74%的铜。共培养研究表明，在50 μM铜胁迫下，WR10增加了小麦幼苗的根长和干重。这些结果表明，WR10是一种抗铜菌株，可降低小麦中的铜毒性。小麦根的转录组数据和生化测试表明，WR10通过增强过氧化物酶（PODs）基因表达和活性以去除过量的过氧化氢（HO），并下调谷胱甘肽S-转移酶（GSTs）以提高谷胱甘肽（GSH）水平，从而减轻铜毒性。此外，富集和通路分析表明，WR10调节了参与苯丙烷生物合成的基因表达，这可能会增加酚酸积累，从而保护植物细胞免受铜毒性。总体而言，本研究表明，高海拔芽孢杆菌WR10通过增强活性氧清除和苯丙烷生物合成来减轻小麦中的铜毒性。
