Evolutionary and Functional Analysis of SlyA in Salmonella typhimurium

Slya;gel shift;Salmonella

Boutt, Elizabeth Ann ; Stephen J. Libby, Committee Chair,Boutt, Elizabeth Ann ; Stephen J. Libby ; Committee Chair

University:North Carolina State University

关键词: Slya;    gel shift;    Salmonella;   

Others  :  https://repository.lib.ncsu.edu/bitstream/handle/1840.16/2245/etd.pdf?sequence=1&isAllowed=y

美国|英语

来源: null

【 摘 要 】

Salmonella species cause a variety of infections in humans and domestic animals, ranging from mild food poisoning-gastroenteritis Salmonella typhimurium to severe systemic disease Salmonella typhi.Salmonella is used as a paradigm to understand how intracellular pathogens withstand the onslaught of the host innate immune system, namely the professional macrophage.SlyA is a global transcriptional regulator that is necessary for the virulence of Salmonella typhimurium. In a mouse model system, a slyA mutant is profoundly attenuated for virulence and is unable to survive in macrophages.To understand the evolutionary history of SlyA in Eubacteria, a phylogenetic analysis was performed.Several alignments of amino acid sequences were constructed with MarR and also with known SlyA homologues.Searches for other SlyA homologues were undertaken using databases of unfinished and finished microbial genomes and more than 50 putative homologues were found.SlyA has been classified as a MarR-like transcriptional regulator by homology.This classification may not be appropriate given the differences in function.Therefore it is suggested that a new class of SlyA-like regulators be formed incorporating all of the homologues found in this study.In order to determine the extent of the SlyA regulon, studies were conducted to analyze the DNA-binding properties of SlyA.The target promoters from this study included genes that were shown to be either activated or repressed by SlyA by utilizing a Salmonella genomic DNA microarray.SlyA was shown to bind specifically to the promoters of clyA, pagC, pagK and mig-14.The approximate Kd values appear to be similar between each of the promoters indicating a similar propensity for SlyA to bind.