Effect of traditional Chinese medicine monomers interfering with quorum-sensing on virulence factors of extensively drug-resistant Acinetobacter baumannii

Abstract

The antimicrobial resistance of Acinetobacter baumannii (A. baumannii) clinical isolates has emerged as a great threat to public health. Quorum sensing (QS) is one of the resistance mechanisms for drug-resistant A. baumannii. Interfering with QS is a promising strategy to combat infections caused by drug-resistant bacteria. This study explored the QS inhibition ability of thirty-four traditional Chinese medicine monomers (TCMMs) and assessed the effect of QS inhibitors (QSIs) on the virulence factors of twelve extensively drug-resistant A. baumannii (XDRAB) strains. Nine traditional Chinese medicine monomers, such as caffeic acid, cinnamic acid, and myricetin, were found to be able to inhibit the bacterial QS. Then, at 1/8 of the minimal inhibitory concentration, we found that these QSIs inhibited extensively drug-resistant A. baumannii adhesion and biofilm formation and downregulated the expression levels of virulence-associated genes (abaI, abaR, csuE, pgaA, and bap). In conclusion, nine traditional Chinese medicine monomers have QS inhibitory activity and may downregulate QS genes to interfere with the QS system, which could inhibit the expression of extensively drug-resistant A. baumannii virulence factors. These results suggest that traditional Chinese medicine monomers could develop as novel anti-virulence compounds to control extensively drug-resistant A. baumannii infections.

Acinetobacter baumannii biofilm was inhibited by tryptanthrin through disrupting its different stages and genes expression

“…Nine traditional Chinese medicine monomers (TCMMs), such as caffeic acid, cinnamic acid, and vanillin, have exhibited QS inhibitory activity, thereby hindering biofilm formation and diminishing virulence. 43 In this study, treatment with tryptanthrin led to a reduction in the expression of the abaI/abaR gene. The two-component system (TCS) is a microbial signaling mechanism that enables the perception of and adaptation to changing environmental conditions.…”

Global Trends in and Hotspots of Bacterial Quorum Sensing: A Bibliometric Analysis for the Period 2012–2022

“…Unclear Inhibition of the QS system; the specific mechanism awaits further research Inhibition of adhesion and biofilm formation, and downregulation of the expression levels of virulence-associated genes [91] Traditional Chinese medicine Tanreqing (TRQ) formula Inhibition of upstream regulators of QS systems, including two-component systems GacS/GacA and PprA/PprB Inhibition of virulence factors [92] QSIs, quorum sensing inhibitors; AHL, acylated homoserine lactone; AI, autoinducer; AIP, autoinducing peptide; PQS, Pseudomonas quinolone signal.…”

Antimildew Effect of Three Phenolic Compounds and the Efficacy of Antimildew Sliced Bamboo Veneer

“…The components of Chinese herbal medicines are extremely complex, and the extraction and separation of their active antimicrobial ingredients can improve the efficiency of mildew inhibitors [ 13 , 14 , 15 , 16 ]. Some Chinese herbal medicines have identified antimicrobial monomers [ 17 , 18 , 19 ] and determined their chemical structures [ 20 , 21 , 22 , 23 ]. It has been reported that among Chinese herbal antimicrobial substances, phenolic compounds exhibit the strongest antimicrobial activity, followed by aldehydes, alcohols, ketones, esters, and hydrocarbons [ 24 ].…”