The P-type ATPase PA1429 Regulates Quorum-sensing Systems And Bacterial Virulence In Pseudomonas Aeruginosa

Pseudomonas aeruginosa is an important opportunistic pathogen that can cause urinary system and respiratory system infections.It displays universal antibiotic resistance and environmental adaptability.Therefore,controlling and prevention of P.aeruginosa become a very important project in the field of pathogenic microorganisms.In P.aeruginosa,quorum-sensing(QS)system controls an array of virulence genes expression and plays a key role in the pathogenic process.The P.aeruginosa QS system consists of a complex regulatory networks.There are at least three QS systems,including Las,Rhl and PQS systems.Although much studies have focused on their functions,the regulatory mechanism is not yet fully elucidated.In this study,we constructed a transposon mutagenesis library and identified 11 genes that affects the expression of pqsH,a gene required for PQS synthesis.Among them,we focus on investigating the function of PA1429.We engineered a PA1429 deletion mutant and found that the expression of pqsH was drastically increased in PA1429 mutant compared to the wild-type PAO1.Consistently,PA1429 also represses the activity of Las and Rhl-related genes.In addition,deletion of PA1429 mutant influences bacterial motility,biofilm formation,and pathogenicity in the acute lung infection model.Furthermore,mutation of PA1429 displays more sensitive to oxidative stress,and this sensitivity is mediated by PqsH.In summary,we describes a new protein that controls QS and virulence factor expression and investigates its regulatory mechanism.These results expand our understanding of the complex regulatory networks of QS system,which will provides insight into controlling P.aeruginosa infection.