Zhao Kelei, Du Lianming, Lin Jiafu, Yuan Yang, Wang Xiwei, Yue Bisong, Wang Xinrong, Guo Yidong, Chu Yiwen, Zhou Yingshun
Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China.
Institute for Advanced Study, Chengdu University, Chengdu, China.
Front Microbiol. 2018 Oct 11;9:2287. doi: 10.3389/fmicb.2018.02287. eCollection 2018.
It is reported that a wide range of bacterial infections are polymicrobial, and the members in a local microcommunity can influence the growth of neighbors through physical and chemical interactions. is an important opportunistic pathogen that normally causes a variety of acute and chronic infections, and clinical evidences suggest that can be frequently coisolated with other pathogens from the patients with chronic infections. However, the interspecific interaction and the coexisting mechanism of with coinfecting bacterial species during evolution still remain largely unclear. In this study, the relationships of with other Gram-positive () and Gram-negative () are investigated by using a series of on-plate proximity assay, coevolution assay, and RNA-sequencing. We find that although the development of a quorum-sensing system contributes a significant growth advantage to compete with and , the quorum-sensing regulation of will be decreased during evolution and thus provides a basis for the formation of interspecific coexistence. The results of comparative transcriptomic analyses suggest that the persistent survival of in the microcommunity has no significant effect on the intracellular transcriptional pattern of , while a more detailed competition happens between and . Specifically, the population of with decreased quorum-sensing regulation can still restrict the proportion increase of by enhancing the type VI secretion system-elicited cell aggressivity during further coevolution. These findings provide a general explanation for the formation of a dynamic stable microcommunity consisting of more than two bacterial species, and may contribute to the development of population biology and clinical therapy.
据报道，多种细菌感染是多微生物性的，局部微生物群落中的成员可通过物理和化学相互作用影响邻近菌的生长。[病原体名称]是一种重要的机会致病菌，通常会引发各种急慢性感染，临床证据表明，在慢性感染患者中，[病原体名称]经常与其他病原体共同分离出来。然而，在进化过程中，[病原体名称]与共感染细菌物种之间的种间相互作用和共存机制仍 largely不清楚。在本研究中，通过一系列平板邻近试验、[病原体名称]共进化试验和RNA测序，研究了[病原体名称]与其他革兰氏阳性（[革兰氏阳性菌名称]）和革兰氏阴性（[革兰氏阴性菌名称]）菌的关系。我们发现，尽管群体感应系统的发育为[病原体名称]与[革兰氏阳性菌名称]和[革兰氏阴性菌名称]竞争提供了显著的生长优势，但在进化过程中，[病原体名称]的群体感应调节会降低，从而为种间共存的形成提供了基础。比较转录组分析结果表明，[病原体名称]在微生物群落中的持续存活对[革兰氏阳性菌名称]的细胞内转录模式没有显著影响，而[病原体名称]与[革兰氏阳性菌名称]之间发生了更详细的竞争。具体而言，群体感应调节降低的[病原体名称]群体在进一步共进化过程中，仍可通过增强VI型分泌系统引发的细胞攻击性来限制[革兰氏阳性菌名称]比例的增加。这些发现为包含两种以上细菌物种的动态稳定微生物群落的形成提供了一般性解释，并可能有助于群体生物学和临床治疗的发展。
