The Mechanism And Function Of SlyA Transcription Factor Of MarR Family In Pseudomonas Fluorescein 2P24

The MarR family is an ancient and important transcriptional regulator widely expressed in archaea.And MarR is responsible for the regulation of gene expression under stress conditions.SlyA protein is a transcription factor belonging to the MarR family,which regulates the viability and virulence factor expression of a variety of pathogenic bacteria in host.Pseudomonas fluorescens is an important biocontrol bacterium,however,the regulation mechanism and function of SlyA protein have been rarely reported.Considering the Cofitness between SlyA and emhR,a transcription factors regulating the efflux pumps EmhABC,we explored SlyA regulation mechanism and function of fluorescent Pseudomonas 2P24.We found SlyA adjust the expression of emhABC gene,and the resistance to some antibiotics of slyA knockout fluorescent Pseudomonas 2P24 strains reduced.Moreover,SlyA negatively regulates its own gene expression.SlyA activates or inhibits the expression of its downstream genes by binding to the promoters of these genes.The general formula of recognition binding DNA sequence of SlyA is a pseudo-palindromic sequence TTA-N₆-TAA.In this paper,the promoter region of pseudomonas fluorescens 2P24genome contains TTA-N₆-TAA,which is a candidate gene for SlyA regulation.Mass spectrometry data analysis showed that?slyA strain and?phoP strain had high parallel protein expression differences.Both strains showed enhanced biofilm forming ability,and?slyA strain biofilm formation ability was slightly stronger than?phoP strain.In addition,the swimming and swarming ability of?slyA strain was greatly enhanced.Before discovering the identity of SlyA,we also searched for the small molecular ligand of SlyA,but failed.At the end of the paper,we summarized the reports on SlyA regulation pathway and drew a summary diagram of SlyA regulation mechanism.We hope this conclusion can serve as a blueprint for the future direction of the study.There are two research directions in this paper in the future.One is to find the upstream and downstream signals of SlyA,confirm whether the upstream signal is PhoQ-PhoP,and use molecular biological methods to find the downstream genes regulated by SlyA.The second is to explore which genes directly regulate these traits based on phenotype,and confirm the relationship between these genes and SlyA in bacteria.These two directions lead to the same conclusion,and finally a complete signal pathway network about SlyA protein is drawn.