Crystal structure of TcpK in complex with oriT DNA of the antibiotic resistance plasmid pCW3.
Nat Commun
; 9(1): 3732, 2018 09 13.
Article
em En
| MEDLINE
| ID: mdl-30213934
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.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Plasmídeos
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Proteínas de Bactérias
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DNA Bacteriano
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Resistência Microbiana a Medicamentos
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Cristalografia por Raios X
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article