title: Identification and Characterization of Novel Compounds Blocking Shiga Toxin Expression inEscherichia coliO157:H7.
abstract: Infections caused by Shiga toxin (Stx)-producingE. colistrains constitute a health problem, as they are problematic to treat. Stx production is a key virulence factor associated with the pathogenicity of enterohaemorrhagicE. coli(EHEC) and can result in the development of haemolytic uremic syndrome in infected patients. The genes encoding Stx are located on temperate lysogenic phages integrated into the bacterial chromosome and expression of the toxin is generally coupled to phage induction through the SOS response. We aimed to find new compounds capable of blocking expression of Stx type 2 (Stx2) as this subtype of Stx is more strongly associated with human disease. High-throughput screening of a small-molecule library identified a lead compound that reduced Stx2 expression in a dose-dependent manner. We show that the optimized compound interferes with the SOS response by directly affecting the activity and oligomerization of RecA, thus limiting phage activation and Stx2 expression. Our work suggests that RecA is highly susceptible to inhibition and that targeting this protein is a viable approach to limiting production of Stx2 by EHEC. This type of approach has the potential to limit production and transfer of other phage induced and transduced determinants.
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Huerta-Uribe
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Zoe R
authors.initials: ZR
authors.lastname: Marjenberg
authors.affiliation: Division of Immunity and Infection, The Roslin Institute and R(D)SVS, The University of Edinburgh Edinburgh, UK.
authors.forename: Nao
authors.initials: N
authors.lastname: Yamaguchi
authors.affiliation: Division of Immunity and Infection, The Roslin Institute and R(D)SVS, The University of Edinburgh Edinburgh, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Fitzgerald
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: James P R
authors.initials: JP
authors.lastname: Connolly
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Nuria
authors.initials: N
authors.lastname: Carpena
authors.affiliation: Laboratories for Chemical Biology Umeå, Department of Chemistry, Umeå University Umeå, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Uvell
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Gillian
authors.initials: G
authors.lastname: Douce
authors.affiliation: Laboratories for Chemical Biology Umeå, Department of Chemistry, Umeå University Umeå, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Elofsson
authors.affiliation: School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Olwyn
authors.initials: O
authors.lastname: Byron
authors.affiliation: Department of Chemistry, Xi'an Jiaotong-Liverpool University Suzhou, China.
authors.forename: Rudi
authors.initials: R
authors.lastname: Marquez
authors.affiliation: Division of Immunity and Infection, The Roslin Institute and R(D)SVS, The University of Edinburgh Edinburgh, UK.
authors.forename: David L
authors.initials: DL
authors.lastname: Gally
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Roe
keywords: E. coli; RecA; Shiga toxin; expression; phage