DNase is a powerful tool for a series of molecular biology applications. Developing a strategy for large-scale production of DNase with high purity and activity is critical for scientific research. In this study, a previously uncharacterized gene with nuclease activity was found in Trichogramma pretiosum genome. Pichia pastoris GS115 was preferred as the host to overcome the issues related to prokaryotic expression. Under the optimal conditions, the activity of T. pretiosum DNase (Tp-DNase) reached 1940 U/mL of culture supernatant in fed-batch fermentation. Using ion-exchange chromatography and adsorption chromatography, Tp-DNase was produced with a purity of >99% and molecular weight of 45 kDa. In vitro DNA degradation experiments showed that Tp-DNase could effectively degrade dsDNA, and its activity was slightly higher than that of bovine pancreas DNase I under the same conditions. Moreover, Tp-DNase can be used to eliminate nucleic acid contamination and improve the accuracy of nucleic acid detection.

DNase 是一系列分子生物学应用的强大工具。制定大规模生产高纯度和活性 DNase 的策略对于科学研究至关重要。在这项研究中，在Trichogramma pretiosum基因组中发现了一个以前未鉴定的具有核酸酶活性的基因。Pichia pastoris GS115 被优选作为宿主来克服与原核表达相关的问题。在最佳条件下，补料分批发酵培养上清液T. pretiosum DNase（Tp -DNase）的活性达到1940 U/mL。使用离子交换色谱和吸附色谱，Tp-生产的 DNase 纯度 >99%，分子量为 45 kDa。体外DNA降解实验表明，Tp- DNase能有效降解dsDNA，在相同条件下其活性略高于牛胰腺DNase I。此外，Tp -DNase可用于消除核酸污染，提高核酸检测的准确性。