Yount Taylor A, Murtha Andrew N, Cecere Andrew G, Miyashiro Tim I
Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA.
Isr J Chem. 2023 Jun;63(5-6). doi: 10.1002/ijch.202200061. Epub 2022 Nov 2.
Quorum sensing is an intercellular signaling mechanism that enables bacterial cells to coordinate population-level behaviors. How quorum sensing functions in natural habitats remains poorly understood. is a bacterial symbiont of the Hawaiian bobtail squid and depends on LuxI/LuxR quorum sensing to produce the symbiotic trait of bioluminescence. A previous study demonstrated that animals emit light when co-colonized by a Δ mutant, which lacks several genes within the operon that are necessary for bioluminescence production, and a LuxI mutant, which cannot synthesize the quorum signaling molecule -3-oxohexanoyl-homoserine lactone. Here, we build upon that observation and show that populations of LuxI feature elevated promoter activity for the operon. We find that population structures comprising of Δ and LuxI are attenuated within the squid, but a wild-type strain enables the LuxI strain type to be maintained . These experimental results support a model of interpopulation signaling, which provides basic insight into how quorum sensing functions within the natural habitats found within a host.
群体感应是一种细胞间信号传导机制，使细菌细胞能够协调群体水平的行为。群体感应在自然栖息地中的功能仍知之甚少。费氏弧菌是夏威夷短尾乌贼的一种细菌共生体，依赖LuxI/LuxR群体感应来产生生物发光的共生特性。先前的一项研究表明，当动物被一个Δ突变体（该突变体在发光操纵子内缺乏几个产生生物发光所必需的基因）和一个LuxI突变体（不能合成群体信号分子3-氧代己酰高丝氨酸内酯）共同定殖时，动物会发光。在此，我们基于该观察结果进一步研究，发现LuxI群体中发光操纵子的启动子活性升高。我们发现，由Δ突变体和LuxI突变体组成的群体结构在乌贼体内会减弱，但野生型菌株能够使LuxI菌株类型得以维持。这些实验结果支持了一种群体间信号传导模型，该模型为群体感应在宿主内自然栖息地中的功能提供了基本见解。
