Abstract：
Quorum sensing (QS) is a cell-to-cell communication mechanism mediated by small diffusible signaling molecules. Previous studies showed that RpfR controls Burkholderia cenocepacia virulence as a cis-2-dodecenoic acid (BDSF) QS signal receptor. Here, we report that the fatty acyl-CoA ligase DsfR (BCAM2136), which efficiently catalyzes in vitro synthesis of lauryl-CoA and oleoyl-CoA from lauric acid and oleic acid, respectively, acts as a global transcriptional regulator to control B. cenocepacia virulence by sensing BDSF. We show that BDSF binds to DsfR with high affinity and enhances the binding of DsfR to the promoter DNA regions of target genes. Furthermore, we demonstrate that the homolog of DsfR in B. lata, RS02960, binds to the target gene promoter, and perception of BDSF enhances the binding activity of RS02960. Together, these results provide insights into the evolved unusual functions of DsfR that control bacterial virulence as a response regulator of QS signal.
摘要：
群体感应（QS）是由小的可扩散信号分子介导的细胞间通讯机制。先前的研究表明，RpfR作为顺式-2-十二碳烯酸（BDSF）QS信号受体控制伯克霍尔德氏菌的毒力。这里,我们报道了脂酰辅酶A连接酶DsfR（BCAM2136），有效催化月桂酸和油酸体外合成月桂酰辅酶A和油酰辅酶A，分别,作为一个全局转录调节因子，通过感知BDSF来控制黑斑芽孢杆菌的毒力。我们表明BDSF以高亲和力结合DsfR，并增强DsfR与靶基因启动子DNA区域的结合。此外，我们证明了B.lata中DsfR的同源物，RS02960，与靶基因启动子结合，和BDSF的感知增强RS02960的结合活性。一起,这些结果提供了对DsfR的进化异常功能的见解，这些功能控制作为QS信号的响应调节剂的细菌毒力。
