ChIP‐seq and transcriptome analysis of the OmpR regulon of Salmonella enterica serovars Typhi and Typhimurium reveals accessory genes implicated in host colonization. Issue 3 (19th December 2012)

• Record Type: Journal Article
• Authors: Perkins, Timothy T.; Davies, Mark R.; Klemm, Elizabeth J.; Rowley, Gary; Wileman, Thomas; James, Keith; Keane, Thomas; Maskell, Duncan; Hinton, Jay C. D.; Dougan, Gordon; Kingsley, Robert A.
• Is Part Of: Molecular microbiology. Volume 87:Issue 3(2013)
• Page Start: 526
• Page End: 538
• Publication Date: 2012-12-19
• Subjects: Molecular microbiology -- Periodicals; 572.829
• DOI: 10.1111/mmi.12111
• Languages: English
• ISSNs: 0950-382X

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>OmpR is a multifunctional DNA binding regulator with orthologues in many enteric bacteria that exhibits classical regulator activity as well as nucleoid‐associated protein‐like characteristics. In the enteric pathogen <italic>Salmonella enterica</italic>, using chromatin immunoprecipitation of OmpR:FLAG and nucleotide sequencing, 43 putative OmpR binding sites were identified in <italic>S. enterica</italic> serovar Typhi, 22 of which were associated with OmpR‐regulated genes. Mutation of a sequence motif (TGTWACAW) that was associated with the putative OmpR binding sites abrogated binding of OmpR:6×His to the <italic>tviA</italic> upstream region. A core set of 31 orthologous genes were found to exhibit OmpR‐dependent expression in both <italic>S.</italic> Typhi and <italic>S.</italic> Typhimurium. <italic>S.</italic> Typhimurium‐encoded orthologues of two divergently transcribed OmpR‐regulated operons (SL1068–71 and SL1066–67) had a putative OmpR binding site in the inter‐operon region in <italic>S.</italic> Typhi, and were characterized using <italic>in vitro</italic> and <italic>in vivo</italic> assays. These operons are widely distributed within <italic>S. enterica</italic> but absent from the closely related <italic>Escherichia coli</italic>. SL1066 and SL1067 were required for growth on <italic>N</italic>‐acetylmuramic acid as a sole carbon source. SL1068–71 exhibited sequence similarity to sialic acid uptake systems and contributed to colonization of the ileum and caecum in the streptomycin‐pretreated mouse model of colitis.</p> </abstract>