基质依赖的策略,以减轻硫酸盐抑制的微生物降解脱的多二二
Chen Chen1, Guofang Xu1, Jianzhong He1
1Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore.
Chemosphere
|September 6, 2023
概括
硫酸盐通过竞争电子捐赠者或产生有毒硫化物来抑制多二 (PCB) 脱. 铁盐和甲基生物可以减轻这种抑制,帮助PCB生物修复.
科学领域:
- 环境微生物学 环境微生物学
- 生物修复是一种生物修复.
- 环境化学环境化学
背景情况:
- 硫酸盐通常与多二 (PCB) 在地下环境中共存.
- 众所周知,硫酸盐阻碍了酸化溶剂的微生物降解.
- 硫酸盐对芳香PCB降解脱的影响及其机制尚不清楚.
研究的目的:
- 研究硫酸盐抑制在微生物减少性脱PCB的机制.
- 探索减轻硫酸盐抑制的基质依赖策略.
- 了解硫化物毒性和电子捐赠者竞争在PCB脱中的作用.
主要方法:
- 使用了Dehalococcoides mccartyi CG1和Desulfovibrio desulfuricans F1. 的共同培养物.
- 操纵硫酸盐和电子供体 (乳酸盐) 度.
- 测量了PCB脱率,硫化物度和还原性脱酶基因表达 (pcbA1).
主要成果:
- 低硫酸盐 (2mM) 通过电子捐赠者竞争抑制了PCB脱.
- 高硫酸盐 (5毫米) 导致硫化物产生 (∼5毫米),抑制脱化约78%.
- 硫化物直接抑制了pcbA1基因表达,但铁盐和甲素减轻了这种抑制.
结论:
- 硫酸盐抑制PCB脱是基质依赖的,涉及电子供体竞争和硫化物毒性.
- 铁盐和甲增强是硫化物抑制的有效缓解策略.
- 研究结果为在富含硫酸盐的条件下优化PCB污染现场的生物修复提供了洞察力.
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