通过选择性抑制酸盐降解酶以生物安全的近位溶剂DMSO实现稳定部分脱
Zhi-Bin Wang1,2, Jinpeng Zhang1,3, Qinshu Miao1
1School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China.
Environmental science & technology
|November 19, 2024
概括
甲基二硫氧化物 (DMSO) 通过选择性抑制酸盐减少酶 (NIR) 来实现稳定的部分脱. 这一战略确保了对anammox细菌的一致的酸盐供应,这对于废水处理应用至关重要.
科学领域:
- 环境微生物学 环境微生物学
- 生物化学工程 生物化学工程
背景情况:
- 部分脱 (PD) 是一种有前途的方法,可以为anammox细菌提供酸盐.
- 在PD中实现稳定的酸盐积累是具有挑战性的,因为酸盐减少酶的活性高于酸盐减少酶 (NIR).
研究的目的:
- 使用二甲基硫氧化物 (DMSO) 开发一种高效稳定的PD工艺.
- 阐明DMSO选择性抑制NIR活动的机制.
主要方法:
- 研究了DMSO对PD过程稳定性和酸盐积累的影响.
- 分析了DMSO对酸盐减少酶 (NIR) 和酸盐减少酶 (NAR) 基因表达和酶活性的影响.
- 在NIR上确定了DMSO抑制的结合亲和力和机制.
主要成果:
- 添加DMSO有效抑制了NIR基因表达和酶活性,使PD稳定.
- 1%的DMSO显著抑制了NIR,而3.5%的DMSO几乎完全抑制了它的活性.
- DMSO对NIR (-3.1 kcal/mol) 的亲和力比NAR (-2.4 kcal/mol) 的亲和力更高,与酸盐结合到与酸盐相同的催化部位.
- DMSO对NAR活动的抑制是最小的.
结论:
- DMSO是一种安全有效的添加剂,可实现稳定的部分脱.
- DMSO对NIR的选择性抑制为优化生物废水处理中酸盐供应提供了一种新的策略.
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