6OZX

Wild type GapR crystal structure 1 from C. crescentus

Summary for 6OZX

• Entry DOI: 10.2210/pdb6ozx/pdb
• Descriptor: UPF0335 protein CC_3319 (2 entities in total)
• Functional Keywords: dna-binding, cell-division, dna binding protein
• Biological source: Caulobacter vibrioides (strain ATCC 19089 / CB15)
• Total number of polymer chains: 1
• Total formula weight: 12911.60

Authors

Tarry, M.,Harmel, C.,Taylor, J.A.,Marczynski, G.T.,Schmeing, T.M. (deposition date: 2019-05-16, release date: 2019-11-27, Last modification date: 2024-03-13)

Primary citation

Tarry, M.J.,Harmel, C.,Taylor, J.A.,Marczynski, G.T.,Schmeing, T.M.
Structures of GapR reveal a central channel which could accommodate B-DNA.
Sci Rep, 9:16679-16679, 2019

PubMed Abstract: GapR is a nucleoid-associated protein required for the cell cycle of Caulobacter cresentus. We have determined new crystal structures of GapR to high resolution. As in a recently published structure, a GapR monomer folds into one long N-terminal α helix and two shorter α helices, and assembles into a tetrameric ring with a closed, positively charged, central channel. In contrast to the conclusions drawn from the published structures, we observe that the central channel of the tetramer presented here could freely accommodate B-DNA. Mutation of six conserved lysine residues lining the cavity and electrophoretic mobility gel shift experiments confirmed their role in DNA binding and the channel as the site of DNA binding. Although present in our crystals, DNA could not be observed in the electron density maps, suggesting that DNA binding is non-specific, which could be important for tetramer-ring translocation along the chromosome. In conjunction with previous GapR structures we propose a model for DNA binding and translocation that explains key published observations on GapR and its biological functions.

PubMed: 31723182
DOI: 10.1038/s41598-019-52964-2

Experimental method

X-RAY DIFFRACTION (1.851 Å)