The system of Strep-Tactin and StrepII tag-SSB proteins binding (ST-SSB) was established to isolate the purified single-stranded DNA in a single step with low cost and high efficiency. We demonstrate that in the presence of large amounts of dsDNA, the ssDNA binding specificity of Escherichia coli (E. coli) single stranded DNA binding (EcSSB) protein was stronger than gene-5-protein (g5p). ST-SSB system relies on the affinity between Strep-Tactin, StrepII tag-SSB protein and ssDNA in binding buffer. Here, we successfully isolated the purified ssDNA from mixed DNA (ds- and ss-DNA form) samples and asymmetric polymerase chain reaction (aPCR) products. This system can purify ssDNA in a single tube within 1 h, and the recovery efficiency of purified ssDNA was around 60%. The ST-SSB system has obvious advantages of high efficiency and one-step purification to recycle any ssDNA.

中文翻译：

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单链DNA分离系统的构建

建立了Strep-Tactin和StrepII tag-SSB结合系统（ST-SSB），以低成本、高效率一步分离纯化的单链DNA。我们证明在存在大量 dsDNA 的情况下，大肠杆菌 (E.coli) 单链 DNA 结合 (EcSSB) 蛋白的 ssDNA 结合特异性强于基因 5-蛋白 (g5p)。ST-SSB 系统依赖于结合缓冲液中 Strep-Tactin、StrepII 标签-SSB 蛋白和 ssDNA 之间的亲和力。在这里，我们成功地从混合 DNA（ds-和 ss-DNA 形式）样本和不对称聚合酶链反应 (aPCR) 产物中分离出纯化的 ssDNA。该系统可在单管内1h内纯化ssDNA，纯化后ssDNA的回收率在60%左右。