Mutations in the csgD Promoter Associated with Variations in Curli Expression in Certain Strains of Escherichia coli O157:H7

Authors

• Gaylen A. Uhlich, Roman L. Hruska U.S. Meat Animal Research Center, USDA-ARS, Clay Center, Nebraska
• James E. Keen, Roman L. Hruska U.S. Meat Animal Research Center, USDA-ARS, Clay Center, NebraskaFollow
• Robert O. Elder, Roman L. Hruska U.S. Meat Animal Research Center, USDA-ARS, Clay Center, Nebraska

Document Type

Article

Date of this Version

5-1-2001

Comments

Published in APPLIED AND ENVIRONMENTAL MICROBIOLOGY, May 2001, p. 2367–2370.

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.