Waters M S, Sturm C A, El-Naggar M Y, Luttge A, Udwadia F E, Cvitkovitch D G, Goodman S D, Nealson K H
Department of Molecular Biology, University of Southern California, Los Angeles, CA, USA.
Geobiology. 2008 Jun;6(3):254-62. doi: 10.1111/j.1472-4669.2008.00161.x. Epub 2008 May 6.
To understand the development of biofilms on metal surfaces, analysis of initial bacterial attachment to surfaces is crucial. Here we present the results of a study, using Shewanella oneidensis MR-1 as a model organism, in which vertical scanning interferometry (VSI) was used to investigate the initial stages of cell attachment to glass, steel and aluminium surfaces. It was found that while VSI gave unambiguous results with opaque surfaces, when reflective surfaces were used, an artifact sometimes appeared, with the bacteria appearing as rod-shaped pits rather than as cells on the surface. When the bacteria were altered to increase opacity, this artifact disappeared, and upon further investigation, it was found that the observational artifact was the result of a conflict between light reflected from the bacteria and the light reflected from the bacteria-metal interface. These results suggest that not only can bacteria be measured on surfaces using VSI, but with some modifications to the analytical software, there may be a unique window for studying the bacterial/substrate interface that can be used for quantitative observations. Imaging and characterization of the bacteria-substrate interface in vivo (previously invisible) will provide new insights into the interactions that occur at this important juncture.
为了解生物膜在金属表面的形成过程，分析细菌对表面的初始附着情况至关重要。在此，我们展示了一项以嗜冷栖热袍菌MR-1作为模式生物的研究结果，该研究中使用垂直扫描干涉测量法（VSI）来探究细胞附着于玻璃、钢和铝表面的初始阶段。研究发现，虽然VSI在不透明表面上能给出明确的结果，但当使用反射性表面时，有时会出现一种假象，细菌呈现为棒状凹坑而非表面上的细胞。当改变细菌以增加不透明度时，这种假象消失了，进一步研究发现，这种观察假象是细菌反射的光与细菌 - 金属界面反射的光之间冲突的结果。这些结果表明，不仅可以使用VSI测量表面上的细菌，而且对分析软件进行一些修改后，可能会有一个用于研究细菌/底物界面的独特窗口，可用于定量观察。对体内（以前不可见）细菌 - 底物界面进行成像和表征，将为在这个重要节点发生的相互作用提供新的见解。
