Escherichia coli GyrA Tower Domain Interacts with QnrB1 Loop B and Plays an Important Role in QnrB1 Protection from Quinolone Inhibition.
Antimicrob Agents Chemother
; 65(7): e0040221, 2021 06 17.
Article
en En
| MEDLINE
| ID: mdl-33846132
ABSTRACT
The Qnr pentapeptide repeat proteins interact with DNA gyrase and protect it from quinolone inhibition. The two external loops, particularly the larger loop B, of Qnr proteins are essential for quinolone protection of DNA gyrase. The specific QnrB1 interaction sites on DNA gyrase are not known. In this study, we investigated the interaction between GyrA and QnrB1 using site-specific photo-cross-linking of QnrB1 loop B combined with mass spectrometry. We found that amino acid residues 286 to 298 on the tower domain of GyrA interact with QnrB1 and play a key role in QnrB1 protection of gyrase from quinolone inhibition. Alanine replacement of arginine at residue 293 and a small deletion of amino acids 286 to 289 of GyrA resulted in a decrease in the QnrB1-mediated increase in quinolone MICs and also abolished the QnrB1 protection of purified DNA gyrase from ciprofloxacin inhibition.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Quinolonas
/
Girasa de ADN
/
Proteínas de Escherichia coli
Idioma:
En
Revista:
Antimicrob Agents Chemother
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos