Analysis ofcepAand otherBacteroides fragilisgenes reveals a unique promoter structure

• DOI: 10.1111/j.1574-6968.2000.tb09417.x
• Publication Date: 2006-01-10T07:35:29Z
• Authors: Douglas P Bayley; Edson R Rocha; C.Jeffrey Smith
• Keywords: Chloramphenicol O-Acetyltransferase; DNA, Bacterial; 0303 health sciences; Base Sequence; Molecular Sequence Data; beta-Lactamases; Artificial Gene Fusion; 3. Good health; Bacteroides fragilis; 03 medical and health sciences; Genes, Bacterial; Mutation; Cloning, Molecular; Promoter Regions, Genetic; Sequence Alignment

There is little known about the sequences that mediate the initiation of transcription in Bacteroides fragilis, thus transcriptional start sites for 13 new genes were determined and a total of 23 promoter regions upstream of the start sites were aligned and similarities were noted. A region at about -7 contained a consensus sequence of TAnnTTTG and upstream in the region centered at about -33, another TTTG motif was found in the majority of promoters examined. Canonical, Escherichia coli, -10 and -35 consensus sequences were not readily apparent. Mutations within the -7 motif indicated the TTTG residues were essential since changes in this sequence reduced the promoter activity to that of a no promoter control in a chloramphenicol acetyl transferase transcriptional fusion model system. Additional fusion studies indicated that the -33 region was also necessary for full activity.