State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Lab Chip. 2017 Dec 19;18(1):190-196. doi: 10.1039/c7lc00993c.
Lipases are ubiquitous enzymes of great physiological significance that have been used extensively in multiple industries. Environmental microorganisms are a major source for the discovery of novel lipases with high catalytic efficiency and selectivity. However, current plate-based screening of lipase-producing strains is time consuming, labour intensive and inefficient. In this study, we developed an ultra-high throughput screening pipeline for lipase-producing strains based on fluorescence-activated droplet sorting (FADS) using a compact optical system that could be easily set up in an alignment-free manner. The pipeline includes droplet generation, droplet incubation, picoinjection of the fluorescence probe, and sorting of droplets with a throughput of 2 × 10 drops per h. We applied the pipeline to screen samples collected from different locations, including sediments from a hot spring in Tibet, soils from the Zoige wetland, contaminated soils from an abandoned oilfield, and a Chinese Daqu starter. In total, we obtained 47 lipase-producing bacterial strains belonging to seven genera, including Staphylococcus, Bacillus, Enterobacter, Serratia, Prolinoborus, Acinetobacter, and Leclercia. We believe that this FADS-based pipeline could be extended to screen various enzymes from the environment, and may find wide applications in breeding of industrial microorganisms.
脂肪酶是具有重要生理意义的广泛存在的酶，已广泛应用于多个行业。环境微生物是发现具有高催化效率和选择性的新型脂肪酶的主要来源。然而，目前基于平板的产脂肪酶菌株筛选既耗时、费力又效率低下。在本研究中，我们开发了一种基于荧光激活液滴分选（FADS）的超高通量产脂肪酶菌株筛选流水线，该流水线使用了一个紧凑的光学系统，可以以无需对准的方式轻松搭建。该流水线包括液滴生成、液滴孵育、荧光探针的皮升级注射，以及每小时 2×10 滴的液滴分选通量。我们应用该流水线筛选了来自不同地点的样品，包括西藏温泉沉积物、若尔盖湿地土壤、废弃油田污染土壤和中国大曲 starter。总共获得了 47 株属于 7 个属的产脂肪酶细菌菌株，包括葡萄球菌、芽孢杆菌、肠杆菌、沙雷氏菌、普林诺伯氏菌、不动杆菌和勒克氏菌。我们相信，这种基于 FADS 的流水线可以扩展到筛选环境中的各种酶，并且可能在工业微生物的选育中得到广泛应用。
