title: Amino acid residues in the Ler protein critical for derepression of the LEE5 promoter in enteropathogenic E. coli.
abstract: Enteropathogenic E. coli causes attaching and effacing (A/E) intestinal lesions. The genes involved in the formation of A/E lesions are encoded within a chromosomal island comprising of five major operons, LEE1-5. The global regulator H-NS represses the expression of these operons. Ler, a H-NS homologue, counteracts the H-NS-mediated repression. Using a novel genetic approach, we identified the amino acid residues in Ler that are involved in the interaction with H-NS: I20 and L23 in the C-terminal portion of α-helix 3, and I42 in the following unstructured linker region.
authors.affiliation: Department of Microbiology, Chonnam National University Medical School, Gwangju, 61186, Republic of Korea.
authors.forename: Su-Mi
authors.initials: SM
authors.lastname: Choi
authors.affiliation: Department of Microbiology, Chonnam National University Medical School, Gwangju, 61186, Republic of Korea.
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Jeong
authors.affiliation: Department of Microbiology, Chonnam National University Medical School, Gwangju, 61186, Republic of Korea. hyonchoy@jnu.ac.kr.
authors.forename: Hyon E
authors.initials: HE
authors.lastname: Choy
authors.affiliation: Department of Microbiology, Kyungpook National University School of Medicine, Daegu, 41944, Republic of Korea. shinms@knu.ac.kr.
authors.forename: Minsang
authors.initials: M
authors.lastname: Shin
mesh_terms: D020816:Amino Acid Motifs; D015536:Down-Regulation; D054308:Enteropathogenic Escherichia coli / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D009876:Operon; D010750:Phosphoproteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D015534:Trans-Activators / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; C457340:LEE protein, E coli; C465556:Ler protein, E coli; D010750:Phosphoproteins; D015534:Trans-Activators
keywords: H-NS; LEE; Ler; enteropathogenic E. coli (EPEC); transcription repression