title: sodC genes expression in Escherichia coli O157:H7 strains.
abstract: BACKGROUND
  E. coli O157:H7 has three sodC genes encoding for Cu,Zn superoxide dismutase. We evaluated the expression of chromosomal sodC in distinct phases of growth in different strains, and we examined the mutual capability of chromosomal and prophagic genes to influence their expression.
  
  
  METHODS
  We used One Step real-time RT-PCR technology to study the expression of sodC genes in several E. coli strains.
  
  
  RESULTS
  In three of four analysed E. coli O157:H7 strains the chromosomal sodC gene was more expressed in exponential phase than in stationary phase, unlike it occurs in the E. coli K12 strain. The expression of the chromosomal gene was always higher than that of the prophagic copies. Deletion of prophagic or chromosomal sodC genes had no effect on the expression of the residual gene.
  
  
  CONCLUSIONS
  Our study highlights an inherent variability in number and level of expression of sodC genes in E. coli O157:H7 strain.
authors.affiliation: Servizio Biologico per la Gestione della Sperimentazione Animale, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Scotti
authors.affiliation: Servizio Biologico per la Gestione della Sperimentazione Animale, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Nicolini
authors.affiliation: Servizio Biologico per la Gestione della Sperimentazione Animale, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Gabbianelli
mesh_terms: D019453:Escherichia coli O157 / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D014644:Genetic Variation; D016133:Polymerase Chain Reaction; D012329:RNA, Bacterial / Q000235:genetics; D013482:Superoxide Dismutase / Q000235:genetics*; D000072105:Superoxide Dismutase-1 / Q000235:genetics*
chemical_list: D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; C116114:sodC protein, E coli