Hypoionic Shock Potentiates Aminoglycoside Antibiotics To Rapidly Kill Multiple Persisters And Aquatic Pathogens Bacteria

Since the use of antibiotic therapy in clinical and breeding industry in the last century to treat bacterial infections,with the widespread use and even abuse of antibiotics,bacteria graduall y develop resistance to antibacterial drugs in order to adapt to the environment.Persister are phenotypic variants that exhibit transient ant ibiotic tolerance and play a leading role in chronic infections and the development of antibiotic resistance.Deter mining the mechanism that underlies persister formation and developing new antipersister strategies,therefore,will be of great significance to the clinical and breeding industry.When bacteria run out of nutrients to grow,a drop in metabolic flux can cause it to enter a dormant or slow-growing state,making it more resistant to antibiotics.Here,we report that bacteria can be induced to fo rm persister by nutrient shift or starvation induced,that is,Escherichia coli and Staphylococcus aureus will be highl y resistant to antibiotics after the induction of culture with fumarate acid or inorganic salt solution.Further research indicates that hypoionic shock（e.g.,the absence of ions）facilitates aminogl ycoside antibiotics killing nutrient shift-or starvation-induced Escherichia coli but not for Staphylococcus aureus persister cells,which is achieved by suspending the persisters in a minogl ycoside antibiotics-containing pure water and incubate them for 3 min.Mechanistically,hypoionic shock dramatically enhances a minoglycoside uptake by nutrient shift-and starvation-induced Escherichia coli persisters,Whereas,such potentiation can be abo lished by adding inhibitors of the electron transport chain（e.g.,Na N ₃）or uncoupler（e.g.,CCCP）to reduce ATP or proton motive force.Based on these results,it indicates that this potentiates is dependent on bacterial respiration.However,hypoionic sh ock cannot be used to kill both nutrient shift-and starvation-induced Staphylococcus aureus by enhancing the uptake of a minogl ycoside antibiotics,which seems to indicate that hypoionic shock is onl y effective against gram-negative bacteria.Additionally,further research shows that hypoionic shock also facilitates the eradication of aquatic pathogens bacteria（e.g.,Aeromonas hydrophila）by aminogl ycoside antibiotics,and that such potentiation can also be significantly suppressed by CCCP or FCCP.Similar ly,hypoionic shock therapy can effectively elimate Aeromonas hydrophila attached to wounds on the surface of zebrafish and thus reduce its mortality,which indicates that the therapy can effectively and rapidl y kill the aquatic pathogens bacteria,and due to short contact with antibiotics,also can reduce its residue in organisms,to avoid pollution to the environment.In addition,hypoionic shock can promote gentamicin to rapidl y kill biofilm-like bacteria（e.g.,Pseudomonas aeruginosa）attached to urina ry catheters.Results of this study indicates that fumarate play a vital role in the formation of bacterial persister and that hypoionic shock facilitates aminogl ycoside antibiotics killing multiple bacterial persisters in a short time,which may open up n ew avenues to use aminogl ycoside antibiotics to eliminate persister.