Trottier Mylène C, de Oliveira Pereira Thays, Groleau Marie-Christine, Hoffman Lucas R, Dandekar Ajai A, Déziel Eric
Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada.
Departments of Pediatrics and Microbiology, University of Washington, Seattle, Washington, USA.
mBio. 2024 Mar 13;15(3):e0237623. doi: 10.1128/mbio.02376-23. Epub 2024 Feb 5.
, a bacterium causing infections in immunocompromised individuals, regulates several of its virulence functions using three interlinked quorum sensing (QS) systems (, , and ). Despite its presumed importance in regulating virulence, dysfunction of the system regulator LasR occurs frequently in strains isolated from various environments, including clinical infections. This newfound abundance of LasR-defective strains calls into question existing hypotheses regarding their selection. Indeed, current assumptions concerning factors driving the emergence of LasR-deficient isolates and the role of LasR in the QS hierarchy must be reconsidered. Here, we propose that LasR is not the primary master regulator of QS in all genetic backgrounds, even though it remains ecologically significant. We also revisit and complement current knowledge on the ecology of LasR-dependent QS in , discuss the hypotheses explaining the putative adaptive benefits of selecting against LasR function, and consider the implications of this renewed understanding.
一种在免疫功能低下个体中引起感染的细菌，利用三个相互关联的群体感应（QS）系统（LasI/LasR、RhlI/RhlR和IqsA）调节其多种毒力功能。尽管其在调节毒力方面可能很重要，但LasR系统调节因子LasR的功能障碍在从包括临床感染在内的各种环境中分离出的菌株中经常出现。这种新发现的大量LasR缺陷菌株使关于它们选择的现有假设受到质疑。事实上，目前关于驱动LasR缺陷分离株出现的因素以及LasR在QS层次结构中的作用的假设必须重新考虑。在这里，我们提出，即使LasR在生态学上仍然具有重要意义，但在所有铜绿假单胞菌遗传背景中，它并非QS的主要主调节因子。我们还重新审视并补充了当前关于铜绿假单胞菌中依赖LasR的QS生态学的知识，讨论了解释选择对抗LasR功能的假定适应性益处的假设，并考虑了这种新认识的影响。
