有机配体控制微生物吸收Hg(II):对Hg(II) 种类和细菌生理学的影响
Yuping Xiang1, Yueqian Chen2, Yingying Guo3
1Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, PR China; Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
Water research
|July 23, 2025
概括
有机配体显著影响 (Hg (II)) 对微生物的生物利用性. 氨酸和谷氨增强了Hg(II) 的吸收,而其他配体则抑制了它,揭示了超出简单结合强度的复杂相互作用.
科学领域:
- 环境微生物学 环境微生物学
- 生物地质化学生物地质化学
- 污染的水银污染情况
背景情况:
- 了解有机配体如何影响微生物 (Hg(II)) 的生物可用性,对于预测甲基的产生和生物积累至关重要.
- 有机配体,如乙二胺四酸 (EDTA),酸盐 (CTA),氨酸 (CYS),谷氨 (GSH),2,3-二次-1-硫酸盐 (DMPS) 和3-三次-1-硫酸盐 (MPS),具有多种功能组,可以改变Hg (II) 的特异化和运输.
研究的目的:
- 研究六种模型有机配体对Hg (II) 对大肠杆菌的生物可用性的影响.
- 阐明控制联体介导Hg(II) 吸收和生物可用性的机制,考虑Hg结合强度,细胞生理和硫化物特异性.
主要方法:
- 使用HgII特异性和构成性细菌生物传感器 (大肠杆菌PRL和大肠杆菌PJL) 来测量活跃的细胞HgII和细胞生理.
- 进行了Hg(II) 变异分析和热力学建模,以了解变异.
- 研究了环境氧气水平对Hg的生物可用性的影响.
主要成果:
- EDTA,CTA,DMPS和MPS抑制了Hg(II) 的吸收,但CYS和GSH增强了它,这表明除了简单的膜-连接体交换之外的机制.
- 生物可用性与Hg结合强度没有反向相关,这表明了复杂的相互作用.
- 由硫酸盐减少和CYS降解驱动的细菌细胞附近的硫化物形成促进了HgS纳米粒子或形成,通过被动扩散和细胞内溶解增强了CYS/GSH复合物的生物可用性.
- 无毒条件增强了Hg(II) -CYS的吸收,可能是由于细菌代谢和转运体表达的改变.
结论:
- 干特异性机制控制了Hg的生物可用性对微生物.
- Hg的生物可用性受到Hg结合强度,细菌生理学和硫化物驱动的物种化的组合的影响.
- 这些发现对于理解水银的生态化学循环和水生环境中甲基的形成至关重要.
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