摘要
【目的】探究1株植物促生菌洋葱伯克霍尔德菌菌株JLS17对Cd^(2+)的耐受与去除能力以及在Cd^(2+)胁迫下的代谢响应,以期为菌株在土壤镉污染修复的应用提供基础理论依据,并为阐明具有抗镉功能分子与代谢途径的挖掘及微生物Cd^(2+)耐受机制提供数据支撑。【方法】通过测定含不同Cd^(2+)浓度培养液的吸光度(OD600)值评价菌株对Cd^(2+)的耐受性,利用电感耦合等离子体质谱仪(ICP-MS)测定菌株对LB培养基中Cd^(2+)的去除效果,采用非靶向代谢组学技术(LC-MS)分析菌株在Cd^(2+)胁迫下的差异代谢物与代谢途径。【结果】1)不同程度的Cd^(2+)胁迫(50~800 mg·L^(−1))均对菌株JLS17的生长速率及生物量增长(OD600)有明显的抑制作用,且抑制作用随Cd^(2+)浓度的升高而不断加剧。2)菌株JLS17对LB培养基中Cd^(2+)的去除量随Cd^(2+)浓度的提高(10~100 mg·L^(−1))而增加,最高去除量可达55.90 mg·L^(−1),但去除率受Cd^(2+)浓度影响相对较小,维持在41.9%~66.0%。3)LC-MS分析结果表明,菌株JLS17在50 mg·L^(−1)和300 mg·L^(−1)的Cd^(2+)浓度胁迫处理下,共有147种差异代谢物表达趋势一致,其中92种共性上调,55种共性下调,主要涉及氨基酸及其衍生物、核苷酸及其衍生物、脂质、有机酸及其衍生物、萜类、酮类、生物碱等。KEGG富集分析结果表明,菌株JLS17在50 mg·L^(−1)和300 mg·L^(−1)的Cd^(2+)浓度胁迫处理下显著富集的共有代谢通路为嘧啶代谢、氨基苯甲酸酯降解、半胱氨酸和蛋氨酸代谢、色氨酸代谢、β-丙氨酸代谢、叶酸的生物合成与磷酸戊糖途径,其中嘧啶代谢、色氨酸代谢、磷酸戊糖途径共性下调,叶酸的生物合成共性上调。【结论】1)菌株JLS17对Cd^(2+)胁迫具有极强的适应性,并能有效去除LB培养基中的Cd^(2+),在镉污染修复中具有良好的应用潜力。2)菌株JLS17在Cd^(2+)胁迫下可通过氨基酸及其衍生物、核苷酸及其�
`【Objective】This study investigated the tolerance and removal ability of the plant growth-promoting bacterium Burkholderia contaminans JLS17 to Cd^(2+)and its metabolic response under Cd^(2+)stress,so as to provide a basic theoretical basis for the application of the strain in soil Cd pollution remediation,and to provide data support for exploring molecules and metabolic pathways with anti-cadmium function and the elucidation of the microbial Cd tolerance mechanism.【Method】The tolerance of the strain to Cd^(2+)was evaluated by measuring the OD600 values of cultures with different Cd^(2+)concentrations,the removal efficiency of Cd^(2+)from LB medium was determined using inductively coupled plasma mass spectrometry(ICP-MS),and the differential metabolites and metabolic pathways of the strain under Cd^(2+)stress were analyzed by untargeted metabolomics(LCMS).【Result】1)There was a significant inhibition of Cd^(2+)stress on the growth rate and biomass(OD600)of strain JLS17 with different levels of Cd^(2+)stress(50 mg·L^(−1)−800 mg·L^(−1)),and the inhibition increased with the increasing Cd^(2+)concentration.2)The removal quantity of Cd^(2+)from LB medium by strain JLS17 increased with the increasing Cd^(2+)concentration(10−100 mg·L^(−1))and the highest removal quantity was 55.90 mg·L^(−1).However,the removal rate was less affected by Cd^(2+)concentration and maintained at 41.9%−66.0%.3)The results of LC-MS analysis showed that strain JLS17 had the same expression trend,with 147 differential metabolites,under 50 mg·L^(−1)Cd^(2+)treatment and 300 mg·L^(−1)Cd^(2+)treatment,of which 92 metabolites were up-regulated and 55 metabolites were down-regulated,mainly covering amino acids and their derivatives,nucleotides and their derivatives,lipids,organic acids and their derivatives,terpenoids,ketones,alkaloids,etc.The results of KEGG enrichment analysis showed that strain JLS17 significantly enriched common metabolic pathways after 50 mg·L^(−1)Cd^(2+)treatment and 300 mg·L^(−1)Cd^(2+)
作者
李仰龙
魏书蒙
陈详腾
董玉红
厚凌宇
焦如珍
Li Yanglong;Wei Shumeng;Chen Xiangteng;Dong Yuhong;Hou Lingyu;Jiao Ruzhen(State Key Laboratory of Efficient Production of Forest Resources Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2024年第8期152-163,共12页
Scientia Silvae Sinicae
基金
“修复重金属污染土壤的高富集植物筛选与评估”(青岛斯坦德衡立环境技术研究院有限公司)。
关键词
镉污染
植物促生菌
耐受机理
重金属吸附
代谢组
cadmium pollution
plant growth-promoting bacterium
tolerance mechanism
heavy metal adsorption
metabolome
