1yfb
From Proteopedia
The solution structure of the N-domain of the transcription factor abrB
Structural highlights
FunctionABRB_BACSU Ambiactive repressor and activator of the transcription of genes expressed during the transition state between vegetative growth and the onset of stationary phase and sporulation. It controls the expression of genes spovG and tycA. AbrB binds to the tycA promoter region at two A- and T-rich sites, it may be the sole repressor of tycA transcription.[1] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAbrB is a key transition-state regulator of Bacillus subtilis. Based on the conservation of a betaalphabeta structural unit, we proposed a beta barrel fold for its DNA binding domain, similar to, but topologically distinct from, double-psi beta barrels. However, the NMR structure revealed a novel fold, the "looped-hinge helix." To understand this discrepancy, we undertook a bioinformatics study of AbrB and its homologs; these form a large superfamily, which includes SpoVT, PrlF, MraZ, addiction module antidotes (PemI, MazE), plasmid maintenance proteins (VagC, VapB), and archaeal PhoU homologs. MazE and MraZ form swapped-hairpin beta barrels. We therefore reexamined the fold of AbrB by NMR spectroscopy and found that it also forms a swapped-hairpin barrel. The conservation of the core betaalphabeta element supports a common evolutionary origin for swapped-hairpin and double-psi barrels, which we group into a higher-order class, the cradle-loop barrels, based on the peculiar shape of their ligand binding site. AbrB-like transcription factors assume a swapped hairpin fold that is evolutionarily related to double-psi beta barrels.,Coles M, Djuranovic S, Soding J, Frickey T, Koretke K, Truffault V, Martin J, Lupas AN Structure. 2005 Jun;13(6):919-28. PMID:15939023[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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