原位电离质谱技术在微生物菌株筛选中的应用进展

Advances and applications of ambient ionization mass spectrometry in screening of microbial strains

质谱是一种强大的分析工具,可提供分子量和化学结构信息。它具有高特异性、高灵敏度、快速、普适性、微量和非标记等优点。在合成生物学的“设计-构建-测试-学习”工程化策略中,质谱具有重要的应用潜力。随着质谱仪器及其方法体系的不断发展,质谱,特别是原位电离质谱技术,已经成为检测和筛选微生物菌株的重要工具。它能够获取完整的细胞代谢表型,用于合成生物学中的“测试”环节高通量筛选和成像。本文重点介绍了经典的基质辅助激光解吸/电离质谱技术和基于电喷雾、激光和等离子体的原位电离质谱技术的工作机制。此外,还综述了这些质谱技术可以在无需样品预处理的情况下直接检测完整的微生物细胞,以及在微生物突变文库的高通量筛选和活微生物菌落的质谱成像方面的研究进展。最后,总结了原位电离质谱技术在合成生物学中的应用。原位电离质谱技术具有微量、无标记、高通量、普适性、高灵敏度等特点,将在合成生物学“测试”环节的高通量筛选装备中发挥重要作用。

Mass spectrometry(MS)is a powerful analytical tool that provides information on the molecular weight and chemical structure of analytes.With the advantages of high specificity,sensitivity,speed,universality,minimal sample requirements,and label-free detection,MS holds great potential in the"Design-Build-Test-Learn"engineering strategy employed in synthetic biology.MS,particularly ambient ionization MS(AI-MS)technology,with the continuous development of MS instruments and their methodologies,enables the detection of intact cellular metabolic phenotypes of microbial cells.This makes it an essential tool for high-throughput screening and imaging in the"test"link.Matrix-assisted desorption/ionization MS(MALDI-MS)is a well-established platform for rapid screening of microbial strains,with a throughput of about one second per sample,by directly analyzing intact cells.AI-MS,a novel set of analytical techniques,allows for direct desorption and ionization of cellular metabolic phenotypes from intact cells under open atmospheric pressure without the need for sample preparation.Its real-time,surface,and in situ capabilities make AI-MS suitable for high-throughput analysis and imaging of microbial strains with a throughput of about ten seconds per sample.In this review,we first introduce the desorption and ionization mechanisms of MALDI MS and AI-MS based on electrospray,plasma,and laser,and illuminate these MS methods’analytical processes and their uniqueness for different intact microbial strains.We then summarize important research progresses of MALDI MS and AI-MS in high-throughput screening of microbial mutant libraries and in situ MS imaging of living microbial colonies.Finally,we outline the advantages and limitations of different AI-MS methods for screening microbial strains,and discuss the application of AI-MS in synthetic biology.Compared to time-consuming and labor-intensive liquid or gas chromatography-based cell phenotype detection methods,AI-MS offers low sample requirements,rapid analysis,in situ capabilities,and environmental friendliness,providing an efficient and cost-effective analytic biotechnology platform for strain engineering.MS will play an important role in the development of high-throughput screening equipment in the"test"phase of synthetic biology.