Identification of iron-regulated genes of Helicobacter pylori by a modified Fur titration assay (FURTA-Hp)

The Escherichia coli-based Fur titration assay (FURTA), although a powerful tool for identification of genes regulated by the ferric uptake regulator (Fur), was unsuccessful for the gastric pathogen Helicobacter pylori. The F URTA was modified by construction of an E. coli indicator strain producing H. pylori Fur only. The promoter regions of the ferric citrate receptor hom olog fecA2 and the riboflavin synthesis gene ribBA were both positive in th e modified FURTA, but negative in;the original FURTA. Transcription of fecA 2 and ribBA was demonstrated to be iron-repressed in H. pylori. This type o f modification should allow FURTA analysis for bacteria with Fur binding se quences poorly recognized by E. coli Fur. (C) 2000 Federation of European,M icrobiological Societies. Published by Elsevier Science B.V. All rights res erved.