5w5a

Crystal structure of Mycobacterium tuberculosis CRP-FNR family transcription factor Cmr (Rv1675c)

spinqualitylabelsall models 5w5a, resolution 1.85Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5w5a is a 2 chain structure with sequence from Mycobacterium tuberculosis H37Rv. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.85Å Ligands: CL, MSE, SO4 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function CMR_MYCTU Positively regulates the expression of at least groEL2. Cyclic AMP does not affect transcription in vitro. Publication Abstract from PubMed Mycobacterium tuberculosis (Mtb) encodes two CRP/FNR family transcription factors (TF) that contribute to virulence, Cmr (Rv1675c) and CRPMt (Rv3676). Prior studies identified distinct chromosomal binding profiles for each TF despite their recognizing overlapping DNA motifs. The present study shows that Cmr binding specificity is determined by discriminator nucleotides at motif positions 4 and 13. X-ray crystallography and targeted mutational analyses identified an arginine-rich loop that expands Cmr's DNA interactions beyond the classical helix-turn-helix contacts common to all CRP/FNR family members and facilitates binding to imperfect DNA sequences. Cmr binding to DNA results in a pronounced asymmetric bending of the DNA and its high level of cooperativity is consistent with DNA-facilitated dimerization. A unique N-terminal extension inserts between the DNA binding and dimerization domains, partially occluding the site where the canonical cAMP binding pocket is found. However, an unstructured region of this N-terminus may help modulate Cmr activity in response to cellular signals. Cmr's multiple levels of DNA interaction likely enhance its ability to integrate diverse gene regulatory signals, while its novel structural features establish Cmr as an atypical CRP/FNR family member. Novel structural features drive DNA binding properties of Cmr, a CRP family protein in TB complex mycobacteria.,Ranganathan S, Cheung J, Cassidy M, Ginter C, Pata JD, McDonough KA Nucleic Acids Res. 2017 Nov 20. pii: 4641903. doi: 10.1093/nar/gkx1148. PMID:29165665 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA