在KPC-2β-乳酸酶中N170在基质辅助脱中的结构性作用
Diksha Parwana1, Jing Gu1, Shuang Chen1
1UCL School of Pharmacy, London, UK.
Angewandte Chemie (International ed. in English)
|January 16, 2024
概括
在Klebsiella pneumoniae carbapenemase 2 (KPC-2) 中氨基酸的变化导致对ceftazidime-avibactam的耐药性. 模拟揭示了特定突变,特别是D179如何破坏酶.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- 克莱布西拉肺炎卡巴酶2 (KPC-2) 是一种关键的酶,可以对β-lactam抗生素产生耐药性.
- 塞法胺-阿维巴克坦是一种关键的治疗KPC产生格拉姆阴性细菌引起的感染.
- 在KPC-2中发生的临床突变,特别是在欧米茄循环中,与对Ceftazidime-avibactam的敏感性降低有关.
研究的目的:
- 调查KPC-2变体通过哪些结构机制对Ceftazidime-avibactam产生抗性.
- 阐明特定氨基酸替代物 (R164,D179) 在欧米茄循环中对酶结构和功能的作用.
- 了解这些突变对药物结合和催化活性的影响.
主要方法:
- 采用了加速罕见事件采样和高温度元动力学模拟.
- 对R164和D179变体进行了详细的结构分析.
- 研究了N170构成在药物相互作用和催化作用中的作用.
主要成果:
- D179替代物诱导显著的欧米茄循环障碍,比R164突变更重要.
- 发现N170的构成对药物结合和脱来说至关重要.
- KPC-2 D179变种可能使用基质辅助催化,涉及氨基醇环以增强水解.
- 野生类型的N170形状变化有助于减少脱和改变酶活性.
结论:
- 特定的KPC-2欧米茄循环突变,特别是D179,导致结构变化,从而赋予了Ceftazidime-avibactam耐药性.
- 在KPC-2与阿维巴克坦的相互作用及其催化效率中,N170残留物起着至关重要的,以前被低估的作用.
- 了解这些结构动态,可以了解抗生素耐药性机制和潜在的治疗策略.
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