生成和比较广泛的宿主范围可诱导表达载体,用于包括ESKAPE病原体在内的グラム阴性细菌
Raj K Ginde1,2, Nicholas A Stella1, Rachel C Calvario1
1Charles T. Campbell Ophthalmic Microbiology Laboratory; Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA.
概括
这项研究比较了细菌中的碳水化合物诱导性促进剂,发现跨物种最有效的可诱导性促进剂 (P_rhaB) 是可诱导性促进剂. 它还确定了对Acinetobacter baumannii更好的诱导系统的需求.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物技术是生物技术.
背景情况:
- 诱导性促进体系统对于生物技术和研究中的受控基因表达至关重要.
- 在酵母 (Saccharomyces cerevisiae) 和广泛宿主范围的细菌载体的等离子体上,诱导性促进物的有限可用性阻碍了应用.
- 对各种细菌物种来说,开发多功能诱导性促进体是必不可少的.
研究的目的:
- 在关键细菌物种中对几种碳水化合物诱导性促进体进行受控比较.
- 为了生成和评估含有诱导性促进体和luxCDABE报告系统的穿载体.
- 评估促进剂在Acinetobacter baumannii,大肠杆菌,Klebsiella pneumoniae,Pseudomonas aeruginosa,Pseudomonas fluorescens和Serratia marcescens中的作用.
主要方法:
- 构建集成Saccharomyces cerevisiae和pBBR1广域宿主复制体的穿载体.
- 将从A. baumannii.中分离的四种可诱导碳水化合物的促进剂 (P_BAD,P_rhaB,P_T5,P_xut) 纳入.
- 利用敏感的luxCDABE报告员系统量化六种细菌物种的促进体活动.
主要成果:
- 在肠道细菌中,P_rhaB和P_BAD的诱导性高 (高达5,600倍).
- 在P. aeruginosa中,P_rhaB和P_xut的诱导能力最强 (分别为40倍和10倍).
- 促进剂在P. fluorescens中表现出有限的诱导性 (<10倍),在A. baumannii中无效,而是具有构成性的作用.
结论:
- 在大多数评估的细菌中,Rhamnose诱导促进剂 (P_rhaB) 在测试的碳水化合物诱导促进剂中表现优越.
- 这项研究强调了需要专门为Acinetobacter baumannii开发新的诱导性促进器系统的必要性.
- 产生的穿载体为研究广泛的格拉姆阴性细菌中的基因表达提供了宝贵的工具.
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