Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
J Biosci Bioeng. 2012 Dec;114(6):652-6. doi: 10.1016/j.jbiosc.2012.06.014. Epub 2012 Jul 29.
Motility is one of the most extensively studied cellular events conducted by bacteria, including Escherichia coli. A motility agar plate assay showed that deletion of the rpoS gene enhanced the apparent motility of the E. coli BW25113 strain, which inherently had negligible motility compared to wild-type E. coli strains, such as MG1655, with no effect on cell growth. This enhancement of motility was accompanied by drastic up-regulation of genes involved in the formation and rotation of flagella. Furthermore, an individual cell motility assay showed that the population of ΔrpoS cells had bimodal motility character, and that a minority of this population exhibited a much higher motility rate. These results support a view that a minority population contributes to increasing in apparent motility of the whole population of ΔrpoS cells.
运动性是细菌（包括大肠杆菌）进行的最广泛研究的细胞事件之一。运动性琼脂平板检测显示，rpoS 基因缺失增强了大肠杆菌 BW25113 株的明显运动性，与野生型大肠杆菌株（如 MG1655）相比，该株固有运动性可忽略不计，对细胞生长没有影响。这种运动性的增强伴随着与鞭毛形成和旋转相关的基因的急剧上调。此外，单细胞运动性检测表明，ΔrpoS 细胞群体具有双峰运动特征，其中少数细胞表现出更高的运动速度。这些结果支持这样一种观点，即少数群体有助于增加整个 ΔrpoS 细胞群体的表观运动性。
