Vaidyanathan Seetharaman, Fletcher John S, Goodacre Roy, Lockyer Nicholas P, Micklefield Jason, Vickerman John C
School of Chemical Engineering and Analytical Sciences, and School of Chemistry, Manchester Interdisciplinary Biocentre, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Anal Chem. 2008 Mar 15;80(6):1942-51. doi: 10.1021/ac701921e. Epub 2008 Feb 22.
Imaging using time-of-flight secondary ion mass spectrometry (TOF-SIMS) with buckministerfullerene (C(60)) primary ions offers the possibility of mapping the chemical distribution of molecular species from biological surfaces. Here we demonstrate the capability of the technique to provide biomolecular information from the cell surface as well as from within the surface, as illustrated with the distribution of two antibiotics in Streptomyces coelicolor (a mycelial bacterium). Differential production of the two pigmented antibiotics under salt-stressed and normal conditions in submerged cultivations could be detected from the TOF-SIMS spectra of the bacteria, demonstrating the potential of the technique in studying microbial physiology. Although both the antibiotics were detected on the cell surface, sputter etching with C(60)(+) revealed the spectral features of only one of the antibiotics within the cells. Exploratory analysis of the images using principal component analysis assisted in analyzing the spectral information with respect to peak contributions and their spatial distributions. The technique allows the study of not only lateral but also the depthwise distribution of biomolecules, uniquely enabling exploration of the processes within biological systems with minimal system intervention and with little a priori biochemical knowledge of relevance.
使用以巴基球（C₆₀）作为一次离子的飞行时间二次离子质谱（TOF-SIMS）成像技术，能够绘制生物表面分子种类的化学分布图。在此，我们展示了该技术从细胞表面以及表面内部获取生物分子信息的能力，以天蓝色链霉菌（一种丝状细菌）中两种抗生素的分布为例进行说明。从细菌的TOF-SIMS光谱中，可以检测到在液体培养中盐胁迫和正常条件下两种有色抗生素的差异产生情况，这表明该技术在研究微生物生理学方面具有潜力。尽管在细胞表面检测到了两种抗生素，但用C₆₀⁺进行溅射蚀刻后，仅揭示了细胞内其中一种抗生素的光谱特征。使用主成分分析对图像进行探索性分析，有助于分析光谱信息中峰的贡献及其空间分布。该技术不仅可以研究生物分子的横向分布，还能研究其深度分布，以最少的系统干预和几乎无需先验相关生化知识，独特地实现了对生物系统内部过程的探索。
