Phylogeny of the bacterial superfamily of Crp-Fnr transcription regulators: exploiting the metabolic spectrum by controlling alternative gene programs
- Universitat Karlsruhe
- BATTELLE (PACIFIC NW LAB)
The Crp-Fnr regulators, named after the first two identified members, are DNA-binding proteins which predominantly function as positive transcription factors, though roles of repressors are also important. Among over 1200 proteins with an N-terminally-located nucleotide-binding domain similar to the cAMP receptor protein, the distinctive additional trait of the Crp-Fnr superfamily is a C-terminally-located helix-turn-helix motif for DNA binding. From a curated database of 369 family members exhibiting both features, we provide a protein tree of Crp-Fnr proteins according to their phylogenetic relationships. This results in the assembly of the regulators ArcR, CooA, CprK, Crp, Dnr, FixK, Flp, Fnr, FnrBac, FnrN, MalR, NnrR, NtcA, PrfA, and YeiL and their homologues in distinct clusters. Lead members and representatives of these groups are described, placing emphasis on the less well known regulators and target processes. Several more groups consist of sequence-derived proteins of unknown physiological role; some of them are tight clusters of highly similar members. The Crp-Fnr regulators stand out in responding to a broad spectrum of intracellular and exogenous signals such as cyclic AMP, anoxia, the redox state, oxidative and nitrosative stress, nitric oxide (NO), carbon monoxide (CO), 2-oxoglutarate, or temperature. To accomplish their roles Crp-Fnr members have intrinsic sensory modules allowing the binding of allosteric effector molecules, or have prosthetic groups for the interaction with the signal. The regulatory adaptability and structural flexibility represented in the Crp-Fnr scaffold has led to the evolution of an important group of physiologically versatile transcription factors.
- Research Organization:
- Pacific Northwest National Lab., Richland, WA (US) (US)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 15006019
- Report Number(s):
- PNNL-SA-38845; KJ0101030; TRN: US200402%%310
- Journal Information:
- FEMS Microbiology Reviews, Vol. 27, Issue 5; Other Information: PBD: 30 Dec 2003
- Country of Publication:
- United States
- Language:
- English
Similar Records
Dissimilatory Metabolism of Nitrogen Oxides in Bacteria:Comparative Reconstruction of Transcriptional Networks
Crystallization and preliminary X-ray crystallographic studies of Mycobacterium tuberculosis CRP/FNR family transcription regulator