基于原子力显微镜对黄单胞菌的表面形貌观察及超微剖析

Surface Morphological Analysis and Micro-dissection of Xanthomonas Cell Using Atomic Force Microscope

原子力显微镜是1986年发明的一种用于观察样品表面纳米级三维结构的显微技术。近年来,越来越多的生物研究中开始使用原子力显微镜对生物样品的微观结构进行研究。与光学显微镜和电子显微镜的成像原理不同,原子力显微镜的观察主要依靠纳米级的探针对样品表面进行接触式扫描,无需对样品进行染色、包被处理即可获得样品三维高分辨率图像,同时还可以利用纳米探针对样品进行力学以及其它微操作,从而提供更多的生物特性与信息。黄单胞菌属致病菌是一类有广泛寄主范围的致病菌,其侵染对象涵盖众多瓜果、蔬菜,甚至水稻、木薯等粮食作物,危害极大。对黄单胞菌的功能基因组研究方兴未艾,然而,对黄单胞菌突变体的高分辨率个体表型观察、菌体解剖研究一直是空白。本研究利用原子力显微镜成功地对十字花科黑腐病病菌Xcc 8004菌株进行了表面结构观察,并对戊二醛固定样本进行了表面超微解剖,为黄单胞菌的功能基因研究提供了新颖的表型观察和研究手段。

Atomic force microscope(AFM)is a microscopic technology that was invented in 1986.Its advantages in nanoscale surface three-dimensional observation has made it more and more commonly used on biological samples.Not like the conventional optical and electronic microscope,the imaging of AFM relies on the physical contact between the scanning probe and the sample surface,yielding high-resolution three-dimensional images and no samples pre-treatment such as coloration and embodiment are required.Furthermore,AFM can perform micro scale manipulations on the samples,which may reveal more biological characteristics and information.Xanthomonas is a species of phytopathogen that causes heavy loss in a wide range of agricultural crops,including melon,fruit,vegetable,rice,cassava,etc.Unfortunately,little study on nanoscale morphological analysis in functional genomic study of Xanthomonas has been accomplished so far.In this study,AFM was successfully used in morphological analysis of Xanthomonas campestris pv.campestris strain 8004 and its mutant affected in gumB,Moreover,the glutaraldehyde-fixed cell of the phytopathogen was successfully dissected using AFM,which provided a novel phenotypic observation and research means for the study of functional genes of Xanthomonas.