Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC, 27402, USA.
Department of Biology, University of North Carolina at Greensboro, Greensboro, NC, 27402, USA.
Anal Bioanal Chem. 2018 Jul;410(18):4237-4245. doi: 10.1007/s00216-018-1071-1. Epub 2018 Apr 28.
Mass spectrometry has proven to be a useful technique for rapid identification of bacterial cells. Among various ionization techniques in mass spectrometry, matrix-assisted laser desorption/ionization (MALDI) has been commonly used for the identification of bacterial cells. Recently, MALDI mass spectrometry has also been utilized to distinguish cellular responses. Ambient ionization techniques do support whole bacterial cell analysis, which include desorption electrospray ionization (DESI). Nanospray DESI (nDESI) is a new variant of DESI, and its application to whole-cell mass spectrometry is limited. In this project, the use of nDESI mass spectrometry to measure probiotic Lactobacillus reuteri (LR) cells is explored. A unique and reproducible mass spectral pattern of untreated LR cells was obtained by using 50% methanol/water as nDESI solvent. The use of nDESI mass spectrometry is further extended to distinguish untreated LR cells from treated LR cells that have been exposed to low pH. These findings demonstrate the feasibility of using nDESI in whole-cell mass spectrometry. Graphical abstract ᅟ.
质谱已被证明是一种快速鉴定细菌细胞的有用技术。在质谱中的各种离子化技术中，基质辅助激光解吸/电离（MALDI）已被广泛用于鉴定细菌细胞。最近，MALDI 质谱也被用于区分细胞反应。环境电离技术确实支持整个细菌细胞分析，包括解吸电喷雾电离（DESI）。纳喷雾 DESI（nDESI）是 DESI 的一种新变体，其在全细胞质谱中的应用受到限制。在本项目中，探索了使用 nDESI 质谱测量益生菌罗伊氏乳杆菌（LR）细胞。通过使用 50%甲醇/水作为 nDESI 溶剂，获得了未经处理的 LR 细胞独特且可重复的质谱图谱。nDESI 质谱的使用进一步扩展到区分未处理的 LR 细胞和已暴露于低 pH 值的处理过的 LR 细胞。这些发现表明了使用 nDESI 进行全细胞质谱的可行性。
