This laboratory experiment describes the production and purification of plasmid DNA for undergraduate biochemistry and biotechnology courses. This experiment performed in a one‐week period includes the protocols for plasmid pVAX1‐LacZ production in Escherichia coli DH5α cells and subsequent purification of supercoiled pVAX1‐LacZ. Firstly, the students use a growth medium that favors the replication of the plasmid resulting in a higher plasmid production during exponential growth. Afterwards, alkaline lysis is done to disrupt the bacterial cells and recover pVAX1‐LacZ plasmid. Lastly, they perform the purification of pVAX1‐LacZ supercoiled isoform by L‐histidine chromatography, followed by agarose gel electrophoresis to characterize the separation of supercoiled isoform from contaminants. The proposed experiment provides an opportunity for students to acquire these skills that are routinely used in biochemistry and biotechnology laboratories. © 2019 International Union of Biochemistry and Molecular Biology, 47(6):638–643, 2019.

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质粒生产与纯化：一门基于实验的综合生物化学与生物技术实验室课程

本实验室实验描述了本科生化学和生物技术课程质粒 DNA 的生产和纯化。该实验为期一周，包括在大肠杆菌 DH5α 细胞中生产质粒 pVAX1-LacZ 和随后纯化超螺旋 pVAX1-LacZ 的方案。首先，学生使用有利于质粒复制的生长培养基，从而在指数生长期间产生更高的质粒产量。之后，进行碱裂解以破坏细菌细胞并回收 pVAX1-LacZ 质粒。最后，他们通过 L-组氨酸层析纯化 pVAX1-LacZ 超螺旋异构体，然后进行琼脂糖凝胶电泳以表征超螺旋异构体与污染物的分离。拟议的实验为学生提供了获得这些在生物化学和生物技术实验室中经常使用的技能的机会。© 2019 国际生物化学与分子生物学联盟，47(6):638–643，2019。