Biochemistry, Biophysics, and Genetics of Microorganisms (BBGM), Institute of Life Sciences, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
Biochemistry, Biophysics, and Genetics of Microorganisms (BBGM), Institute of Life Sciences, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
Cell Rep. 2018 Feb 13;22(7):1627-1638. doi: 10.1016/j.celrep.2018.01.055.
Small distortions in transcriptional networks might lead to drastic phenotypical changes, especially in cellular developmental programs such as competence for natural transformation. Here, we report a pervasive circuitry rewiring for competence and predation interplay in commensal streptococci. Canonically, in streptococci paradigms such as Streptococcus pneumoniae and Streptococcus mutans, the pheromone-based two-component system BlpRH is a central node that orchestrates the production of antimicrobial compounds (bacteriocins) and incorporates signal from the competence activation cascade. However, the human commensal Streptococcus salivarius does not contain a functional BlpRH pair, while the competence signaling system ComRS directly couples bacteriocin production and competence commitment. This network shortcut might underlie an optimal adaptation against microbial competitors and explain the high prevalence of S. salivarius in the human digestive tract. Moreover, the broad spectrum of bacteriocin activity against pathogenic bacteria showcases the commensal and genetically tractable S. salivarius species as a user-friendly model for competence and bacterial predation.
转录网络的微小扭曲可能导致剧烈的表型变化，特别是在细胞发育程序中，如自然转化的能力。在这里，我们报告了共生链球菌中竞争和捕食相互作用的普遍电路重排。在典型的链球菌范例中，如肺炎链球菌和变异链球菌，基于信息素的双组分系统 BlpRH 是一个中央节点，它协调抗菌化合物（细菌素）的产生，并整合来自竞争激活级联的信号。然而，人类共生链球菌不包含功能正常的 BlpRH 对，而竞争信号系统 ComRS 直接将细菌素产生和竞争能力结合起来。这种网络捷径可能是对微生物竞争者的最佳适应，并解释了 S. salivarius 在人类消化道中高流行的原因。此外，广谱的细菌素活性对病原菌的作用展示了共生和遗传上易于处理的 S. salivarius 作为竞争和细菌捕食的用户友好模型。
