Evolution of chemotactic hitchhiking-猫眼课题宝

趋化搭便车的进化

DOI：

10.1111/jeb.13695

发表时间：

2020

期刊：

Journal of Evolutionary Biology

影响因子：

2.1

通讯作者：

中科院分区：

生物学3区

文献类型：

作者：

Uppal, Gurdip;Hu, Weiyi;Vural, Dervis Can

细菌通常存在于具有各种化学梯度的异质环境中，其中运动细胞可以获得优于非运动细胞的优势。由于运动是能量消耗，细胞必须优化它们的游泳速度和行为，以最大限度地提高它们的适应性。在这里，我们研究如何作弊策略可能演变缓慢或不动的微生物利用更快的粘在一起，搭便车。从物理和生物的第一原则，我们计算研究的影响，坚持在受控恒化器环境中的运动的演变。我们发现，粘性允许缓慢的骗子占主导地位时，化学引诱物分散在中间距离。在这种情况下，慢的微生物会利用快的微生物，直到它们消耗掉整个种群，导致公地悲剧。在长距离比赛中，慢的微生物确实从粘着中获得了最初的优势，但最终会落后。在这里，快速微生物更有可能粘附到其他快速微生物上，并合作增加自己的种群。因此，我们得出结论，搭便车的相互作用的性质是寄生的或互利的，取决于chemoattractant distribution.AbstractWe模拟一个乐队的微生物执行运行和翻滚趋化性在一个通道中与线性chemoattractant梯度（黄色）。碰撞的微生物粘在一起，直到下一次翻滚。粘着可能是有益的，因为对经历较小的阻力。然而，另一方面，慢的微生物也可以利用快的微生物。我们研究了运行速度分布的存在和不存在粘附的演变，对于不同的通道长度。

Bacteria typically reside in heterogeneous environments with various chemogradients where motile cells can gain an advantage over nonmotile cells. Since motility is energetically costly, cells must optimize their swimming speed and behaviour to maximize their fitness. Here, we investigate how cheating strategies might evolve where slow or nonmotile microbes exploit faster ones by sticking together and hitching a ride. Starting with physical and biological first principles, we computationally study the effects of sticking on the evolution of motility in a controlled chemostat environment. We find that stickiness allows for slow cheaters to dominate when chemoattractants are dispersed at intermediate distances. In this case, slow microbes exploit faster ones until they consume the population, leading to a tragedy of commons. For long races, slow microbes do gain an initial advantage from sticking, but eventually fall behind. Here, fast microbes are more likely to stick to other fast microbes and co‐operate to increase their own population. We therefore conclude that whether the nature of the hitchhiking interaction is parasitic or mutualistic, depends on the chemoattractant distribution.AbstractWe simulate a band of microbes performing run‐and‐tumble chemotaxis in a channel with linear chemoattractant gradient (yellow). Colliding microbes stick together until the next tumble. Sticking can be beneficial, since pairs experience less drag force. However on the flip side, slow microbes can also exploit fast ones. We study the evolution of run speed distribution in the presence and absence of sticking, for different channel lengths.