Skip to main content

Research Repository

Advanced Search

Crystal structure of TcpK in complex with oriT DNA of the antibiotic resistance plasmid pCW3

Crystal structure of TcpK in complex with oriT DNA of the antibiotic resistance plasmid pCW3 Thumbnail


Abstract

Conjugation is fundamental for the acquisition of new genetic traits and the development of antibiotic resistance in pathogenic organisms. Here, we show that a hypothetical Clostridium perfringens protein, TcpK, which is encoded by the tetracycline resistance plasmid pCW3, is essential for efficient conjugative DNA transfer. Our studies reveal that TcpK is a member of the winged helix-turn-helix (wHTH) transcription factor superfamily and that it forms a dimer in solution. Furthermore, TcpK specifically binds to a nine-nucleotide sequence that is present as tandem repeats within the pCW3 origin of transfer (oriT). The X-ray crystal structure of the TcpK–TcpK box complex reveals a binding mode centered on and around the ß-wing, which is different from what has been previously shown for other wHTH proteins. Structure-guided mutagenesis experiments validate the specific interaction between TcpK and the DNA molecule. Additional studies highlight that the TcpK dimer is important for specific DNA binding.

Acceptance Date Jun 15, 2018
Publication Date Sep 13, 2018
Publicly Available Date Mar 28, 2024
Journal Nature Communications
Print ISSN 2041-1723
DOI https://doi.org/10.1038/s41467-018-06096-2
Publisher URL https://www.nature.com/articles/s41467-018-06096-2#Abs1

Files




Downloadable Citations