Castañeda-Tamez Paulina, Ramírez-Peris Jimena, Pérez-Velázquez Judith, Kuttler Christina, Jalalimanesh Ammar, Saucedo-Mora Miguel Á, Jiménez-Cortés J Guillermo, Maeda Toshinari, González Yael, Tomás María, Wood Thomas K, García-Contreras Rodolfo
Department of Microbiology and Parasitology, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Mexico City, Mexico.
Front Microbiol. 2018 Jun 27;9:1348. doi: 10.3389/fmicb.2018.01348. eCollection 2018.
Quorum sensing (QS) in coordinates the expression of virulence factors, such as exoproteases and siderophores, that are public goods utilized by the whole population of bacteria, regardless of whether they invested or not in their production. These public goods can be used by QS defective mutants for growth, and since these mutants do not contribute to public goods production, they are considered social cheaters. Pyocyanin is a phenazine that is a toxic, QS-controlled metabolite produced by . It is a redox-active compound and promotes the generation of reactive oxygen species; it also possesses antibacterial properties and increases fitness in competition with other bacterial species. Since QS-deficient individuals are less able to tolerate oxidative stress, we hypothesized that the pyocyanin produced by the wild-type population could promote selection of functional QS systems in this bacterium. Here, we demonstrate, using competition experiments and mathematical models, that, indeed, pyocyanin increases the fitness of the cooperative QS-proficient individuals and restricts the appearance of social cheaters. In addition, we also show that pyocyanin is able to select QS in other bacteria such as .
群体感应（QS）在[具体细菌名称]中协调毒力因子的表达，如外蛋白酶和铁载体，这些是整个细菌群体都能利用的公共物品，无论它们是否参与了这些物质的产生。这些公共物品可被群体感应缺陷型突变体用于生长，由于这些突变体不参与公共物品的产生，它们被视为社会作弊者。绿脓菌素是一种吩嗪，是由[具体细菌名称]产生的一种受群体感应控制的有毒代谢产物。它是一种具有氧化还原活性的化合物，能促进活性氧的产生；它还具有抗菌特性，并在与其他细菌物种的竞争中提高适应性。由于群体感应缺陷型个体耐受氧化应激的能力较弱，我们推测野生型群体产生的绿脓菌素可能会促进该细菌中功能性群体感应系统的选择。在此，我们通过竞争实验和数学模型证明，事实上，绿脓菌素提高了具有群体感应能力的合作个体的适应性，并限制了社会作弊者的出现。此外，我们还表明绿脓菌素能够在其他细菌如[具体细菌名称]中选择群体感应。
