Abstract

Pseudomonas aeruginosa is one of the most common biofilm-producing bacteria, often leading to long-term and chronic infections. The LasR regulator protein acts as the central regulator of the quorum sensing (QS) system and coordinates the expression of some virulence and biofilm genes. In this study, novel peptides (WSF, FASK, YDVD) were designed for binding to the domain of the transcriptional activator of the LasR protein and interfere with LasR in the QS system of P. aeruginosa. The effects of these peptides on biofilm production, expression of biofilm-related genes (AlgC, PslA, PelA), and growth of planktonic P. aeruginosa were investigated. All three peptides inhibited the growth of P. aeruginosa planktonic cells at 1600 µg ml⁻¹ and exhibited anti-biofilm effects at sub-inhibitory concentrations (800 µg ml⁻¹). Measurements of the mRNA levels of biofilm-related genes at sub-inhibitory concentrations of the designed peptides showed a significant decrease.

摘要

铜绿假单胞菌是最常见的产生生物膜的细菌之一，通常会导致长期和慢性感染。LasR 调节蛋白充当群体感应 (QS) 系统的中央调节器，并协调一些毒力和生物膜基因的表达。在这项研究中，设计了新的肽（WSF、FASK、YDVD）用于与 LasR 蛋白转录激活因子的结构域结合并干扰铜绿假单胞菌QS 系统中的 LasR 。研究了这些肽对生物膜产生、生物膜相关基因（AlgC、PslA、PelA ）的表达和浮游铜绿假单胞菌生长的影响。这三种肽都抑制了P. aeruginosa浮游细胞在 1600  µg ml ^-1 下，在亚抑制浓度 (800 µg ml ^-1 )下表现出抗生物膜作用。在设计肽的亚抑制浓度下对生物膜相关基因的 mRNA 水平的测量显示显着降低。