隐秘的表型变异在碳烯酶的适应性进化过程中迅速出现
Laura Dabos1,2, Inssaf Nedjari3, Alejandro Couce4
1Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Madrid, Spain. dabos.laura@gmail.com.
Nature ecology & evolution
|July 31, 2025
概括
有益的突变可以通过不同的途径导致抗生素耐药性,隐藏的差异会影响酶的成功. 了解这些神秘的变异是预测长期抵抗演变的关键.
科学领域:
- 进化生物学 进化生物学
- 微生物学 微生物学
- 生物化学 生物化学
背景情况:
- 表观症,或有益突变之间的相互作用,强烈影响适应性途径.
- 替代进化解决方案可能表现出类似的初级适应性,但在二级环境中有所不同.
- 抗生素耐药性突变中的神秘的表型差异对附带敏感性和治疗策略有影响.
研究的目的:
- 描述Klebsiella pneumoniae carbapenemase-2 (KPC-2) 突变途径的多样性,进化为抗塞夫塔齐耐药性.
- 通过替代突变轨迹来研究表观体在指导适应中的作用.
- 为了探索KPC-2变异的表型分歧,具有类似的Ceftazidime耐药水平.
主要方法:
- 针对KPC-2的定向进化,以增强对Ceftazidime的活性.
- 鉴定和分析突变和突变轨迹.
- 进化KPC-2变种的表型特征,包括分子和宏观特征.
主要成果:
- 在18个不同的突变轨迹中确定了40个替代物,导致高Ceftazidime耐药性.
- 观察到强烈的表观,根据初始突变将轨迹分为四大组.
- 在表型特征 (稳定性,催化,生长,附带活性) 中表现出显著的差异,尽管存在类似的抗塞夫塔齐抗药性.
结论:
- 在适应过程中,在强有力的选择下,神秘的表型差异迅速积累.
- 表观性塑造了进化轨迹,导致了对抗性酶成功的不可预测的长期后果.
- 了解这些隐藏的变异对于预测抗生素耐药性的传播和影响至关重要.
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