The Myxobacterium Myxococcus xanthus Can Sense and Respond to the Quorum Signals Secreted by Potential Prey Organisms
The Myxobacterium Myxococcus xanthus Can Sense and Respond to the Quorum Signals Secreted by Potential Prey Organisms
复制标题
DOI：
10.3389/fmicb.2017.00439
复制
发表时间：
2017-03-14
影响因子：
5.2
通讯作者：
Whitworth, David E.
中科院分区：
文献类型：
--
作者：
Lloyd, Daniel G.;Whitworth, David E.
黄色粘细菌是土壤微型动物中的一种捕食性成员，能够吞噬细菌(革兰氏阴性和革兰氏阳性)、古生菌和真菌。黄曲霉的许多潜在猎物之间使用酰基高丝氨酸内酯(AHLS)作为法定信号进行通信。黄花根结线虫本身不能产生AHL，但可以通过对近端猎物之间的信号传递过程中产生的外源AHL的反应而潜在地受益。4种不同侧链长度的AHL均能延缓黄花营养细胞的产孢量，促进粘孢子萌发，提高捕食性营养细胞在种群中的比例。黄曲霉种群的捕食活性和膨胀率也受到AHLS的刺激。热灭活的AHLS对黄花莲细胞没有影响，对AHLS的反应(非线性)依赖于AHL侧链的长度，表明AHLS的作用是通过黄花草体内的特定信号介导的，而不是AHLS的化学或物理性质的结果。因此，外源Quorum信号分子的存在似乎增强了黄曲霉的捕食活性。AHLS增加了能够捕食的种群比例，并刺激了营养细胞的运动和捕食活动。因此，我们认为在野外，黄曲霉使用AHL作为附近猎物的标记，潜在地窃听猎物有机体之间的对话。
The myxobacterium Myxococcus xanthus is a predatory member of the soil microfauna, able to consume bacteria (Gram-negative, Gram-positive), archaea, and fungi. Many potential prey of M. xanthus communicate amongst themselves using acyl homoserine lactones (AHLs) as quorum signals. M. xanthus cannot itself produce AHLs, but could potentially benefit by responding to exogenous AHLs produced during signaling between proximal prey. Four AHLs of different side chain length were tested and all found to delay sporulation of M. xanthus vegetative cells, and to stimulate germination of myxospores, increasing the proportion of predatory vegetative cells in the population. The predatory activity and expansion rates of M. xanthus colonies were also found to be stimulated by AHLs. Thermally inactivated AHLs had no effect on M. xanthus cells, and the response to AHLs depended (non-linearly) on the length of AHL side chain, suggesting that the effect of AHLs was mediated by specific signaling within M. xanthus, rather than being a consequence of the chemical or physical properties of AHLs. Therefore, it seems that the presence of xenic quorum signaling molecules enhances the predatory activity of M. xanthus. AHLs increase the proportion of the population capable of predation, and stimulate the motility and predatory activity of vegetative cells. We therefore propose that in the wild, M. xanthus uses AHLs as markers of nearby prey, potentially eavesdropping on the conversations between prey organisms.