Sakaguchi Shoutaro, Taoka Azuma, Fukumori Yoshihiro
Department of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Japan.
Biosci Biotechnol Biochem. 2013;77(5):940-7. doi: 10.1271/bbb.120880. Epub 2013 May 7.
Prokaryotic organelles called magnetosomes allow magnetotactic bacteria to navigate along geomagnetic field lines. In this study, we modified a swimming assay commonly used to assess bacterial motility to develop a new method of assessing magnetotactic motility. By this method, the swimming assay was performed in an artificial magnetic field. Magnetotactic bacteria formed a wedge-shaped swimming halo that elongated parallel to the magnetic field. Magnetotactic motility was qualitatively assessed by comparing halo shapes. We termed this method the magnetic swimming assay. On the magnetic swimming assay, the mamK deletion strain formed a shorter halo than the wild type, indicating that the assay sensitively detects differences in magnetotactic motility. Moreover, we isolated two spontaneous magnetotactic motility mutants using magnetic swimming plates. Our findings indicate that the magnetic swimming assay is a useful method for the sensitive analysis of magnetotaxis phenotypes and mutant screening.
被称为磁小体的原核细胞器使趋磁细菌能够沿着地磁场线导航。在本研究中，我们改进了一种常用于评估细菌运动性的游动试验，以开发一种评估趋磁运动性的新方法。通过这种方法，游动试验在人工磁场中进行。趋磁细菌形成了一个楔形游动晕圈，该晕圈平行于磁场拉长。通过比较晕圈形状对趋磁运动性进行定性评估。我们将这种方法称为磁游动试验。在磁游动试验中，mamK缺失菌株形成的晕圈比野生型短，这表明该试验能灵敏地检测趋磁运动性的差异。此外，我们使用磁游动平板分离出了两个自发的趋磁运动性突变体。我们的研究结果表明，磁游动试验是一种用于灵敏分析趋磁表型和突变体筛选的有用方法。
