MULTIPLE FACTORS UNDERLYING THE MAXIMUM MOTILITY OF ESCHERICHIA-COLI AS CULTURES ENTER POSTEXPONENTIAL GROWTH
MULTIPLE FACTORS UNDERLYING THE MAXIMUM MOTILITY OF ESCHERICHIA-COLI AS CULTURES ENTER POSTEXPONENTIAL GROWTH
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DOI：
10.1128/jb.175.19.6238-6244.1993
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发表时间：
1993-10-01
影响因子：
3.2
通讯作者：
MATSUMURA, P
中科院分区：
文献类型：
--
作者：
AMSLER, CD;CHO, MS;MATSUMURA, P
运动性和趋化性允许细胞远离压力微环境。大肠杆菌在分批培养中的运动性，如通过细胞游泳速度所测量的，在早期指数期细胞中是低的，当细胞进入指数后期时达到峰值，并且下降到早期稳定期。转录从flhB操纵子和鞭毛蛋白的合成同样达到峰值，在指数后期和指数后早期阶段，分别。指数早期和指数后阶段之间的游泳速度的增加与每细胞体积的鞭毛长度和鞭毛密度的两倍增加相关。鞭毛的这种增加的投资可能反映了在不利环境中运动性的适应价值的增加。指数后和稳定期之间的速度下降与鞭毛电机产生的扭矩减少三倍，大概反映了质子动力减少，可用于静止期细胞。
Motility and chemotaxis allow cells to move away from stressful microenvironments. Motility of Escherichia coli in batch cultures, as measured by cell swimming speed, was low in early-exponential-phase cells, peaked as the cells entered post-exponential phase, and declined into early stationary phase. Transcription from the flhB operon and synthesis of flagellin protein similarly peaked in late exponential and early post-exponential phases, respectively. The increase in swimming speed between early-exponential and post-exponential phases was correlated with twofold increases in both flagellar length and flagellar density per cell volume. This increased investment in flagella probably reflects the increased adaptive value of motility in less favorable environments. The decrease in speed between post-exponential and stationary phases was correlated with a threefold decrease in torque produced by the flagellar motors and presumably reflects decreased proton motive force available to stationary-phase cells.