Antibiotic resistance in gram-negative pathogens has become one of the most serious global public health threats.The role of the N-acyl homoserine lactone(AHL)-mediated signaling pathway,which is widespread in gram-ne...Antibiotic resistance in gram-negative pathogens has become one of the most serious global public health threats.The role of the N-acyl homoserine lactone(AHL)-mediated signaling pathway,which is widespread in gram-negative bacteria,in the bacterial resistance process should be studied in depth.Here,we report a degrading enzyme of AHLs,MomL,that inhibits the antibiotic resistance of Pseudomonas aeruginosa through a novel mechanism.The MomL-mediated reactivation of kanamycin is highly associated with the relA-mediated starvation stringent response.The degradation of AHLs by MomL results in the inability of LasR to activate relA,which,in turn,stops the activation of downstream rpoS.Further results show that rpoS directly regulates the type VI secretion system H2-T6SS.Under MomL treatment,inactivated RpoS fails to regulate H2-T6SS;therefore,the expression of effector phospholipase A is reduced,and the adaptability of bacteria to antibiotics is weakened.MomL in combination with kanamycin is effective against a wide range of gram-negative pathogenic bacteria.Therefore,this study reports a MomL-antibiotic treatment strategy on antibiotic-resistant bacteria and reveals its mechanism of action.展开更多
基金the National Natural Science Foundation of China(Nos.42176108 and 31870023)the Young Taishan Scholars Program of Shandong Province(No.tsqn202103029)+2 种基金the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0406-4)the Fundamental Research Funds for the Central Universities(No.201941009)the open research funds of the State Key Laboratory of Ophthalmology(No.303060202400368).
文摘Antibiotic resistance in gram-negative pathogens has become one of the most serious global public health threats.The role of the N-acyl homoserine lactone(AHL)-mediated signaling pathway,which is widespread in gram-negative bacteria,in the bacterial resistance process should be studied in depth.Here,we report a degrading enzyme of AHLs,MomL,that inhibits the antibiotic resistance of Pseudomonas aeruginosa through a novel mechanism.The MomL-mediated reactivation of kanamycin is highly associated with the relA-mediated starvation stringent response.The degradation of AHLs by MomL results in the inability of LasR to activate relA,which,in turn,stops the activation of downstream rpoS.Further results show that rpoS directly regulates the type VI secretion system H2-T6SS.Under MomL treatment,inactivated RpoS fails to regulate H2-T6SS;therefore,the expression of effector phospholipase A is reduced,and the adaptability of bacteria to antibiotics is weakened.MomL in combination with kanamycin is effective against a wide range of gram-negative pathogenic bacteria.Therefore,this study reports a MomL-antibiotic treatment strategy on antibiotic-resistant bacteria and reveals its mechanism of action.
