Genome amplification and promoter mutation expand the range of csgD-dependent biofilm responses in an STEC population.
Microbiology (Reading)
; 163(4): 611-621, 2017 04.
Article
em En
| MEDLINE
| ID: mdl-28406080
ABSTRACT
Expression of the major biofilm components of E. coli, curli fimbriae and cellulose, requires the CsgD transcription factor. A complex regulatory network allows environmental control of csgD transcription and biofilm formation. However, most clinical serotype O157ââH7 strains contain prophage insertions in the csgD regulator, mlrA, or mutations in other regulators that restrict csgD expression. These barriers can be circumvented by certain compensating mutations that restore higher csgD expression. One mechanism is via csgD promoter mutations that switch sigma factor utilization. Biofilm-forming variants utilizing RpoD rather than RpoS have been identified in glycerol freezer stocks of the non-biofilm-forming food-borne outbreak strain, ATCC 43894. In this study we used whole genome sequencing and RNA-seq to study genotypic and transcriptomic differences between those strains. In addition to defining the consequences of the csgD promoter switch and identifying new csgD-controlled genes, we discovered a region of genome amplification in our laboratory stock of 43894 (designated 43894OW) that contributed to the regulation of csgD-dependent properties.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fator sigma
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Proteínas de Bactérias
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RNA Polimerases Dirigidas por DNA
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Regulação Bacteriana da Expressão Gênica
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Transativadores
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Biofilmes
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Escherichia coli O157
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Proteínas de Escherichia coli
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Microbiology (Reading)
Assunto da revista:
MICROBIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Estados Unidos