Effect of environmental and chemotactic stimuli on the activity of the Campylobacter jejuni flaA sigma(28) promoter

The effect of environmental and chemotactic stimuli was assessed using a fu sion between the Campylobacter jejuni flaA sigma (28) promoter and a promot erless luxCDABE cassette on pRYluxCDABE. Environmental stimuli relevant to the enteric environment were found to modulate flaA promoter activity. pH, bovine bile, deoxycholate, L-fucose and osmolarity up-regulated the flaA pr omoter while viscosity resulted in down-regulation. C. jejuni chemotactic e ffectors, including the amino acids aspartate and glutamate and the organic acids citrate, fumarate, alpha -ketoglutarate and succinate up-regulated t he flaA promoter. Proline, which does not elicit a chemotactic response, up -regulated the flaA promoter. (C) 2001 Federation of European Microbiologic al Societies. Published by Elsevier Science B.V. All rights reserved.