RT Journal Article
T1 The expression of aminoglycoside resistance genes in integron cassettes is not controlled by riboswitches
A1 Hipólito, Alberto
A1 García Pastor, Lucía
A1 Trigo da Roza, Filipa
A1 Kieffer, Nicolas
A1 Vergara, Ester
A1 Jové, Thomas
A1 Escudero García-Calderón, José Antonio
A1 Blanco Torres, Paula
A1 Álvarez Sánchez, Julio
AB Regulation of gene expression is a key factor influencing the success of antimicrobial resistance determinants. A variety of determinants conferring resistance against aminoglycosides (Ag) are commonly found in clinically relevant bacteria, but whether their expression is regulated or not is controversial. The expression of several Ag resistance genes has been reported to be controlled by a riboswitch mechanism encoded in a conserved sequence. Yet this sequence corresponds to the integration site of an integron, a genetic platform that recruits genes of different functions, making the presence of such a riboswitch counterintuitive. We provide, for the first time, experimental evidence against the existence of such Ag-sensing riboswitch. We first tried to reproduce the induction of the well characterized aacA5 gene using its native genetic environment, but were unsuccessful. We then broadened our approach and analyzed the inducibility of all AgR genes encoded in integrons against a variety of antibiotics. We could not observe biologically relevant induction rates for any gene in the presence of several aminoglycosides. Instead, unrelated antibiotics produced mild but consistently higher increases in expression, that were the result of pleiotropic effects. Our findings rule out the riboswitch control of aminoglycoside resistance genes in integrons.
PB OUP
SN 0305-1048
YR 2022
FD 2022-08-26
LK https://hdl.handle.net/20.500.14352/94566
UL https://hdl.handle.net/20.500.14352/94566
LA eng
DS Docta Complutense
RD 12 oct 2024