Graduate School of Life Sciences, Toyo University, Oura-gun, Gunma 374-0193, Japan.
Faculty of Life and Environmental Sciences, and Microbiology Research Center for Sustainability (MiCS), University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Biomolecules. 2020 Apr 16;10(4):618. doi: 10.3390/biom10040618.
Motile sp. ME121 and non-motile sp. 32K were isolated from the same soil sample. Interestingly, ME121 was significantly more motile in the coculture of ME121 and 32K than in the monoculture of ME121. This advanced motility of ME121 was also observed in the 32K culture supernatant. A swimming acceleration factor, which we named the K factor, was identified in the 32K culture supernatant, purified, characterized as an extracellular polysaccharide (5-10 kDa), and precipitated with 70% ethanol. These results suggest the possibility that the K factor was directly or indirectly sensed by the flagellar stator, accelerating the flagellar rotation of ME121. To the best of our knowledge, no reports describing an acceleration in motility due to coculture with two or more types of bacteria have been published. We propose a mechanism by which the increase in rotational force of the ME121 flagellar motor is caused by the introduction of the additional stator into the motor by the K factor.
运动性 sp.ME121 和非运动性 sp.32K 是从同一土壤样本中分离得到的。有趣的是，与 ME121 的纯培养相比，在 ME121 和 32K 的共培养物中，ME121 的运动性显著增强。在 32K 培养上清液中也观察到 ME121 的这种先进的运动性。我们在 32K 培养上清液中鉴定出一种游动加速因子，命名为 K 因子，它被纯化并被鉴定为一种细胞外多糖（5-10 kDa），并可以用 70%乙醇沉淀。这些结果表明，K 因子可能直接或间接被鞭毛定子感知，从而加速 ME121 的鞭毛旋转。据我们所知，目前还没有报道描述由于与两种或更多类型的细菌共培养而导致运动性加速的情况。我们提出了一种机制，即通过 K 因子将额外的定子引入到电机中，从而导致 ME121 鞭毛电机的旋转力增加。
