|
type |
Journal Article |
authors |
Rigali, S.; Derouaux, A.; Giannotta, F.; Dusart, J. |
title |
Subdivision of the helix-turn-helix GntR family of bacterial regulators in the FadR, HutC, MocR, and YtrA subfamilies |
journal |
J Biol Chem |
Activity |
mocr |
sel |
selected |
ui |
11756427 |
year |
(2002) |
volume |
277 |
number |
15 |
pages |
12507-15 |
| |
abstract |
Haydon and Guest (Haydon, D. J, and Guest, J. R. (1991) FEMS Microbiol. Lett. 63, 291-295) first described the helix-turn-helix GntR family of bacterial regulators. They presented them as transcription factors sharing a similar N-terminal DNA-binding (d-b) domain, but they observed near-maximal divergence in the C-terminal effector-binding and oligomerization (E-b/O) domain. To elucidate this C-terminal heterogeneity, structural, phylogenetic, and functional analyses were performed on a family that now comprises about 270 members. Our comparative study first focused on the C-terminal E-b/O domains and next on DNA-binding domains and palindromic operator sequences, has classified the GntR members into four subfamilies that we called FadR, HutC, MocR, and YtrA. Among these subfamilies a degree of similarity of about 55% was observed throughout the entire sequence. Structure/function associations were highlighted although they were not absolutely stringent. The consensus sequences deduced for the DNA-binding domain were slightly different for each subfamily, suggesting that fusion between the D-b and E-b/O domains have occurred separately, with each subfamily having its own D-b domain ancestor. Moreover, the compilation of the known or predicted palindromic cis-acting elements has highlighted different operator sequences according to our subfamily subdivision. The observed C-terminal E-b/O domain heterogeneity was therefore reflected on the DNA-binding domain and on the cis-acting elements, suggesting the existence of a tight link between the three regions involved in the regulating process. |
last changed |
2009/07/09 15:31 |
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