Extremophilic Natrinema versiforme Against Pseudomonas aeruginosa Quorum Sensing and Biofilm

Abstract

Pseudomonas aeruginosa is an opportunistic pathogen that causes high morbidity and mortality rates due to its biofilm form. Biofilm formation is regulated via quorum sensing (QS) mechanism and provides up to 1000 times more resistance against conventional antibiotics. QS related genes are expressed according to bacterial population density via signal molecules. QS inhibitors (QSIs) from natural sources are widely studied evaluating various extracts from extreme environments. It is suggested that extremely halophilic Archaea may also produce QSI compounds. For this purpose, we tested QS inhibitory potentials of ethyl acetate extracts from cell free supernatants and cells of Natrinema versiforme against QS and biofilm formation of P. aeruginosa. To observe QS inhibition, all extracts were tested on P. aeruginosa lasB-gfp, rhlA-gfp, and pqsA-gfp biosensor strains and biofilm inhibition was studied using P. aeruginosa PAO1. According to our results, QS inhibition ratios of cell free supernatant extract (CFSE) were higher than cell extract (CE) on las system, whereas CE was more effective on rhl system. In addition, anti-biofilm effect of CFSE was higher than CE. Structural analysis revealed that the most abundant compound in the extracts was trans 4-(2-carboxy-vinyl) benzoic acid.

Natural Anti-biofilm Agents: Strategies to Control Biofilm-Forming Pathogens

“…The majority of these QQ molecules have been isolated from natural sources (LaSarre and Federle, 2013). The result of a recent study revealed QS inhibitory potentials of ethyl acetate extracts from cell-free supernatants and cells of Natrinemaversi forme against P. aeruginosa biofilm (Başaran et al, 2020). Many QS inhibitors from plant-based natural products have been identified (Caceres et al, 2020;Zhong et al, 2020) and proposed to be effective in future biofilm targeting strategies.…”

Titanium-Tantalum Alloy Surface Modification by Hydroxyapatite Layer on TiO2 Nanotubes: Effect on Microbial Activity

“…The Group 2 coating shown a circular hydroxyapatite shape with 4-6 µm diameter. Clearly, the nanoscale surface has strong antimicrobial efficacy by inhibiting the S epidermidis growth 46,[48][49][50][51][52][53] . In previous studies, it was investigated the behavior of gram positive and negative bacteria on TiO 2 nanotubes.…”

Research Progress and Hopeful Strategies of Application of Quorum Sensing in Food, Agriculture and Nanomedicine

“…Biofilm development, mainly in the sessile growth phase, is regulated by intracellular QS interaction [37]. This happens also in different pathogens, including, for example, Pseudomonas aeruginosa, which can colonize and then be transmitted also by food, establishing opportunistic infections with high mortality rates [38]. The potential role of QS in spoilage has recently attracted growing research interest.…”

“…The above-described strategies to counteract the food crisis in an eco-friendly manner are summarized in Table 1. [ [34][35][36][37][38][39][40][41] Moreover, standard laboratory settings are ideal and highly controlled, but cannot extensively represent realistic environments, in which chemical and physical conditions dynamically change. Consequently, further efforts are needed in the study of QS in microbial mixtures of species that mimic real habitat parameters [42].…”