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Mutations in the csgD promoter associated with variations in curli expression in certain strains of Escherichia coli O157:H7.

ABSTRACT: Single-base-pair csgD promoter mutations in human outbreak Escherichia coli O157:H7 strains ATCC 43894 and ATCC 43895 coincided with differential Congo red dye binding from curli fiber expression. Red phenotype csgD::lacZ promoter fusions had fourfold-greater expression than white promoter fusions. Cloning the red variant csgDEFG operon into white variants induced the red phenotype. Substrate utilization differed between red and white variants.

SUBMITTER: Uhlich GA

PROVIDER: S-EPMC92880 | biostudies-literature | 2001 May

REPOSITORIES: biostudies-literature

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Mutations in the csgD promoter associated with variations in curli expression in certain strains of Escherichia coli O157:H7.

Uhlich G A GA Keen J E JE Elder R O RO

Applied and environmental microbiology 20010501 5

Single-base-pair csgD promoter mutations in human outbreak Escherichia coli O157:H7 strains ATCC 43894 and ATCC 43895 coincided with differential Congo red dye binding from curli fiber expression. Red phenotype csgD::lacZ promoter fusions had fourfold-greater expression than white promoter fusions. Cloning the red variant csgDEFG operon into white variants induced the red phenotype. Substrate utilization differed between red and white variants. ...[more]

PMID: 11319125

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