氧化诱导细菌的形态变化
Huan K Nguyen1, Samantha L Picciotti1, Magdalena M Duke1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
ACS infectious diseases
|October 13, 2023
概括
氧化 (NO) 捐赠者损害了阴性细菌的细胞壁,而缓释捐赠者会造成更大的伤害. 需要带正电荷的树枝状体才能穿透格拉姆阳性细菌的细胞壁.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 材料科学 材料科学 材料科学
背景情况:
- 抗菌素耐药性是一个全球性的健康危机,需要新的治疗策略.
- 氧化 (NO) 在病原体反应中发挥作用,并具有潜在的抗菌应用.
- 外源的NO捐赠者为开发新的抗感染治疗提供了一个有希望的途径.
研究的目的:
- 为了研究由各种外源性捐赠者输送的氧化 (NO) 对细菌细胞包裹的影响.
- 评估NO供体架构如何影响格兰阴性和格兰阳性病原体中的细菌壁退化.
- 评估不同NO输送系统对抗抗生素耐药菌株的疗效.
主要方法:
- 使用基于显微镜和光的技术,在NO处理后检查细菌细胞包裹.
- 传输电子显微镜 (TEM) 可视化了细菌细胞壁和膜的结构变化.
- 脱极化试验测量了细胞壁透率作为对NO捐赠者的反应.
主要成果:
- 没有捐赠者导致显著的膜损伤和细胞壁破坏在格拉姆阴性细菌 (Klebsiella pneumoniae,Pseudomonas aeruginosa).
- 从小分子中缓慢释放的NO (t1/2 = 120分钟) 与快速释放 (t1/2 = 24分钟) 相比,导致格拉姆阴性细菌受到更大的损害.
- 无治疗没有显著改变格拉姆阳性细菌 (黄金葡萄球菌,菌菌) 形态,但QA修饰的树状体穿透了它们的细胞壁.
结论:
- 无氧化物供体的结构显著影响它们对细菌细胞包裹的有效性.
- 缓慢释放的NO捐赠者在降解格拉姆阴性细菌细胞壁方面更有效.
- 带正电荷的NO释放型树枝状体具有独特的潜入格兰正细菌的糖层的能力,为治疗这些感染提供了潜在的策略.
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