Magneto-aerotaxis in marine coccoid bacteria
Magneto-aerotaxis in marine coccoid bacteria
复制标题
DOI：
10.1016/s0006-3495(97)78132-3
复制
发表时间：
1997-08-01
影响因子：
3.4
通讯作者：
Taylor, BL
中科院分区：
文献类型：
--
作者：
Frankel, RB;Bazylinski, DA;Taylor, BL
趋磁球菌持续地沿着局部磁场线在一个优选的方向上游动，该方向对应于沿着沿着地磁场线向下迁移。最近，高细胞浓度的趋磁球菌已被发现在化学分层，海洋和半咸水栖息地的水柱，并不总是在沉积物中，如预期的持久性，向下迁移的细菌，在这里，我们报告的细胞的纯培养的海洋趋磁球菌，命名为菌株MC-1，在毛细管中形成微需氧带，并使用趋氧性以氧梯度迁移至优选的氧浓度。细胞能够沿着局部磁场沿着任一方向游动，并结合趋气性使用趋磁性，即，磁辅助趋氧性或磁趋氧性，以更有效地迁移到并保持在它们优选的氧浓度的位置，菌株MC-1的细胞具有一种新的趋氧性感觉机制，其似乎起双向开关的作用，而不是其他细菌，包括磁致趋氧菌（Magnetotacticum）在趋氧性中使用的时间感觉机制，这些细胞还表现出对短波长光（小于或等于1500 nm）的反应，这导致它们在光照期间持续平行于磁场游泳。
Magnetotactic cocci swim persistently along local magnetic field lines in a preferred direction that corresponds to downward migration along geomagnetic field lines. Recently, high cell concentrations of magnetotactic cocci have been found in the water columns of chemically stratified, marine and brackish habitats, and not always in the sediments, as would be expected for persistent, downward-migrating bacteria, Here we report that cells of a pure culture of a marine magnetotactic coccus, designated strain MC-1, formed microaerophilic bands in capillary tubes and used aerotaxis to migrate to a preferred oxygen concentration in an oxygen gradient. Cells were able to swim in either direction along the local magnetic field and used magnetotaxis in conjunction with aerotaxis, i.e., magnetically assisted aerotaxis, or magneto-aerotaxis, to more efficiently migrate to and maintain position at their preferred oxygen concentration, Cells of strain MC-I had a novel, aerotactic sensory mechanism that appeared to function as a two-way switch, rather than the temporal sensory mechanism used by other bacteria, including Magnetospirillum magnetotacticum, in aerotaxis, The cells also exhibited a response to short-wavelength light (less than or equal to 1500 nm), which caused them to swim persistently parallel to the magnetic field during illumination.