title: Understanding the host-adapted state of Citrobacter rodentium by transcriptomic analysis.
abstract: Citrobacter rodentium (Cr) is a mouse pathogen that mimics many aspects of enteropathogenic Escherichia coli infections including producing attaching and effacing (A/E) lesions. Host-adapted (HA) Cr cells that are shed at the peak of infection have been reported to be hyper-infective. The exact mechanism underlying this phenomenon has remained elusive since the pathogen loses its HA 'status' immediately upon subculturing in laboratory media. We sequenced the entire transcriptome of Cr directly from the feces of infected mice and analyzed the gene expression pattern. We observed that the entire transcriptional machinery as well as several transcriptional regulators to be differentially expressed when compared with the transcriptome of cells grown on laboratory media. Major adhesion and effector genes, tir and eae, were highly expressed in HA along with many genes located on all five loci of enterocyte effacement regions (LEE 1-5). Notable absent among the HA expressed genes were 19 fimbrial operons and non-fimbrial adhesions and several non-LEE encoded effectors. These results demonstrate that host-adapted Cr has a unique transcriptome that is associated with increased host transmission.
authors.affiliation: Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, USDA-ARS, 10300 Baltimore Ave., B307C, Rm. 228, BARC-E, Beltsville, MD, 20705, USA. allen.smith@ars.usda.gov.
authors.forename: Allen D
authors.initials: AD
authors.lastname: Smith
authors.affiliation: Environmental, Microbial, and Food Safety Laboratory, Beltsville Agriculture Research Center, USDA-ARS, Beltsville, MD, USA.
authors.forename: Xianghe
authors.initials: X
authors.lastname: Yan
authors.affiliation: Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, USDA-ARS, 10300 Baltimore Ave., B307C, Rm. 228, BARC-E, Beltsville, MD, 20705, USA.
authors.forename: Celine
authors.initials: C
authors.lastname: Chen
authors.affiliation: Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, USDA-ARS, 10300 Baltimore Ave., B307C, Rm. 228, BARC-E, Beltsville, MD, 20705, USA.
authors.forename: Harry D
authors.initials: HD
authors.lastname: Dawson
authors.affiliation: Environmental, Microbial, and Food Safety Laboratory, Beltsville Agriculture Research Center, USDA-ARS, Beltsville, MD, USA.
authors.forename: Arvind A
authors.initials: AA
authors.lastname: Bhagwat
mesh_terms: D000818:Animals; D001483:Base Sequence; D044082:Citrobacter rodentium / Q000235:genetics / Q000502:physiology*; D003470:Culture Media; D004756:Enterobacteriaceae Infections / Q000382:microbiology* / Q000635:transmission; D020869:Gene Expression Profiling; D005798:Genes, Bacterial / Q000235:genetics; D051379:Mice; D059467:Transcriptome
chemical_list: D003470:Culture Media
keywords: Attaching–effacing pathogens; Enteropathogens; Host-adaptation; RNA-seq analysis