## 5 Conclusions  
We identified a new esterase EstDR4 from extremophile \(D\). _radiodurans_. As a newly identified member of family IV esterases, EstDR4 contains typical motifs GDSAG and HGGG. It exhibited maximum catalytic activity at 30 \({}^{\circ}\)C and pH 8 and outstanding catalytic activity at cold conditions, even at 0 \({}^{\circ}\)C. EstDR4 also demonstrated good compatibility with detergent and versatile substrate preferences toward short and medium chain monoesters, phenyl ester, tertiary alcohol and triglyceride. In addition, EstDR4 was able to hydrolyze various insecticides. These identify EstDR4 for potential use in a wide range of industrial applications and warrants further research. **Supplementary Materials:** The following are available online at [[https://www.mdpi.com/2076-341](https://www.mdpi.com/2076-341)]([https://www.mdpi.com/2076-341](https://www.mdpi.com/2076-341)) 7/11/4/1864/s1. **Author Contributions:** Conceptualization, Y.Z., Z.L., M.L. and Z.Z. ; methodology, Y.Z. ; validation, Y.Z. ; formal analysis, Y.Z. ; investigation, Y.Z. ; writing--original draft preparation, Y.Z. ; writing--review and editing, Y.Z., W.L., Z.Z., W.Z., M.C., M.L., Z.L. and J.W. ; supervision, Z.L. and Z.Z. All authors have read and agreed to the published version of the manuscript. **Funding:** This work was supported by National Key R&D Program of China (No. 2019 XFA0901003), the National Transgenic Major Program of China (No. 2019 ZX08010-004), National Natural Science Foundation of China (No. 31930004 and 31500063) and Fundamental Research Fund for Central Non-Profit Scientific Institution (1610392019006). We also appreciate the support of the Agricultural Science and Technology Innovation Program of CAAS. **Data Availability Statement:** Not applicable. **Acknowledgments:** Special thanks go to [PERSON], [PERSON] and [PERSON] for their constructive suggestions on the revision of the article and other authors for their excellent technical support. **Conflicts of Interest:** The authors declare no conflict of interest. * [PERSON] and [PERSON] (2017) [PERSON]; [PERSON] Functional characterization of hormone sensitive-like lipase from Bacillus halodurans: Synthesis and recovery of pNP-laurate with high yields. _Extremophiles_**2017**, _21_, 871-889. [CrossRef]
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