W. M. Keck Science Department of Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, California 91711, United States.
Biochemistry. 2020 Aug 11;59(31):2833-2841. doi: 10.1021/acs.biochem.0c00494. Epub 2020 Jul 27.
DNA is a foundational tool in biotechnology and synthetic biology but is limited by sensitivity to DNA-modifying enzymes. Recently, researchers have identified DNA polymerases that can enzymatically synthesize long oligonucleotides of modified DNA (M-DNA) that are resistant to DNA-modifying enzymes. Most applications require M-DNA to be reverse transcribed, typically using a RNA reverse transcriptase, back into natural DNA for sequence analysis or further manipulation. Here, we tested commercially available DNA-dependent DNA polymerases for their ability to reverse transcribe and amplify M-DNA in a one-pot reaction. Three of the six polymerases chosen (Phusion, Q5, and Deep Vent) could reverse transcribe and amplify synthetic 2'F M-DNA in a single reaction with <5 × 10 error per base pair. We further used Q5 DNA polymerase to reverse transcribe and amplify M-DNA synthesized by two candidate M-DNA polymerases (SFP1 and SFM4-6), allowing for quantification of the frequency, types, and locations of errors made during M-DNA synthesis. From these studies, we identify SFP1 as one of the most accurate M-DNA polymerases identified to date. Collectively, these studies establish a simple, robust method for the conversion of 2'F M-DNA to DNA in <1 h using commercially available materials, significantly improving the ease of use of M-DNA.
DNA 是生物技术和合成生物学的基础工具,但它对 DNA 修饰酶的敏感性有限。最近,研究人员已经鉴定出能够酶促合成对 DNA 修饰酶具有抗性的长链修饰 DNA(M-DNA)寡核苷酸的 DNA 聚合酶。大多数应用都需要将 M-DNA 反转录为天然 DNA,通常使用 RNA 反转录酶,以便进行序列分析或进一步操作。在这里,我们测试了六种市售的 DNA 依赖性 DNA 聚合酶,以评估它们在一锅反应中反转录和扩增 M-DNA 的能力。选择的六种聚合酶中的三种(Phusion、Q5 和 Deep Vent)可以在单个反应中反转录和扩增合成的 2'F M-DNA,每个碱基的错误率<5×10。我们进一步使用 Q5 DNA 聚合酶反转录和扩增由两种候选 M-DNA 聚合酶(SFP1 和 SFM4-6)合成的 M-DNA,从而能够定量分析 M-DNA 合成过程中出现的错误的频率、类型和位置。通过这些研究,我们确定 SFP1 是迄今为止鉴定出的最准确的 M-DNA 聚合酶之一。总的来说,这些研究建立了一种简单、稳健的方法,可在<1 小时内使用市售材料将 2'F M-DNA 转化为 DNA,显著提高了 M-DNA 的易用性。