Identification of the binding site of the sigma(54) hetero-oligomeric FleQ/FleT activator in the flagellar promoters of Rhodobacter sphaeroides
Por:
Pena-Sanchez, J, Poggio, S, Flores-Perez, U, Osorio, A, Domenzain, C, Dreyfus, G, Camarena, L
Publicada:
1 may 2009
Categoría:
Microbiology
Resumen:
Expression of the flagellar genes in Rhodobacter sphaeroides is dependent on one of the four sigma-54 factors present in this bacterium and on the enhancer binding proteins (EBPS) Flea and FIeT. These proteins, in contrast to other well-characterized EBPs, carry out activation as a hetero-oligomeric complex. To further characterize the molecular properties of this complex we mapped the binding sites or upstream activation sequences (UASs) of six different flagellar promoters. In most cases the UASs were identified at approximately 100 bp upstream from the promoter. However, the activity of the divergent promoters flhAp-flgAp, which are separated by only 53 bp, is mainly dependent on a UAS located approximately 200 bp downstream from each promoter. Interestingly, a significant amount of activation mediated by the upstream or contralateral UAS was also detected, suggesting that the architecture of this region is important for the correct regulation of these promoters. Sequence analysis o
Filiaciones:
Pena-Sanchez, J:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
Poggio, S:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
Flores-Perez, U:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
Osorio, A:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
Domenzain, C:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
Dreyfus, G:
Univ Nacl Autonoma Mexico, Inst Fisiol Celular, Mexico City 04510, DF, Mexico
Camarena, L:
Univ Nacl Autonoma Mexico, Inst Invest Biomed, Mexico City 04510, DF, Mexico
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