Summary information and primary citation
- PDB-id
- 5vfx; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- DNA binding protein-DNA
- Method
- X-ray (2.81 Å)
- Summary
- Structure of an accessory protein of the pcw3 relaxosome in complex with the origin of transfer (orit) DNA
- Reference
- Traore DAK, Wisniewski JA, Flanigan SF, Conroy PJ, Panjikar S, Mok YF, Lao C, Griffin MDW, Adams V, Rood JI, Whisstock JC (2018): "Crystal structure of TcpK in complex with oriT DNA of the antibiotic resistance plasmid pCW3." Nat Commun, 9, 3732. doi: 10.1038/s41467-018-06096-2.
- 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 β-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.
