Sakka Kazuo, Kihira Masaki, Kuhara Wataru, Mochida Akihiro, Kimura Tetsuya, Sakka Makiko
Graduate School of Bioresources, Mie University, Tsu, Japan.
Iga Research Center, Mie University, Iga, Japan.
J Basic Microbiol. 2022 Dec;62(12):1475-1486. doi: 10.1002/jobm.202200445. Epub 2022 Oct 3.
Brevibacillus thermoruber strain Nabari was isolated from compost and identified based on 16 S rRNA gene sequencing and DNA-DNA hybridization using B. thermoruber DSM 7064 as the standard, despite some differences in their physiological and structural characteristics. When B. thermoruber Nabari was cultivated on various solid media containing 1.5% agar at 60°C, it rapidly propagated over the entire plate. In particular, on R2A-agar medium, it formed fine dendritic colonies. Macroscopic and microscopic observations of peripheral regions of the colonies indicated that the dendritic patterns were formed by bacterial swarming of some of the cells; large flows of bacterial cell populations were observed in the peripheral regions of the dendritic colonies. The cells were highly flagellated, but no extreme elongation of cells was observed. When B. thermoruber Nabari cells were cultivated at 37°C on R2A-agar plates, most colonies were nonmotile, but some colonies were motile. For example, a wandering colony moved on the plate and split into two, and then they collided to become one again. Additionally, a simple incubation system was devised to record the movement of colonies at high temperatures in this study while protecting the cameras from thermal damage.
热栖短芽孢杆菌纳巴里菌株是从堆肥中分离出来的，并通过16S rRNA基因测序和以热栖短芽孢杆菌DSM 7064为标准的DNA-DNA杂交进行鉴定，尽管它们在生理和结构特征上存在一些差异。当热栖短芽孢杆菌纳巴里菌株在含有1.5%琼脂的各种固体培养基上于60°C培养时，它会在整个平板上迅速繁殖。特别是在R2A琼脂培养基上，它形成了细小的树枝状菌落。对菌落周边区域的宏观和微观观察表明，树枝状图案是由一些细胞的群体游动形成的；在树枝状菌落的周边区域观察到大量的细菌细胞群体流动。细胞具有高度鞭毛，但未观察到细胞的极端伸长。当热栖短芽孢杆菌纳巴里菌株的细胞在R2A琼脂平板上于37°C培养时，大多数菌落不运动，但有些菌落是运动的。例如，一个游动的菌落会在平板上移动并分裂成两个，然后它们又碰撞合并成一个。此外，在本研究中设计了一个简单的培养系统来记录高温下菌落的运动，同时保护相机免受热损伤。
