SALMONELLA-TYPHIMURIUM FIMBRIAL PHASE VARIATION AND FIMA EXPRESSION

Bacteria in a nonfimbriate phase because of continuous aeration of liq uid cultures produce FimA in amounts similar to those produced try fim briate bacteria. However, relatively low FimA production was observed in nonfimbriate-phase cultures obtained by growth on solid media or by anaerobic incubation. Regardless of the fimbrial phase of Salmonella typhimurium, the fimA promoter region was always oriented in the direc tion that might allow fimA transcription.