INVESTIGADORES
ADLER Conrado
congresos y reuniones científicas
Título:
ENTEROBACTIN PROTECTS Escherichia coli FROM THE ROS-MEDIATED TOXIC EFFECTS OF PYOCHELIN
Autor/es:
ADLER CONRADO; PERALTA, DAIANA; MICHAVILA, GABRIELA; POMARES FERNANDA; CORBALAN NATALIA; DE CRISTOBAL RE; VINCENT, PAULA
Lugar:
San Luis
Reunión:
Congreso; SAIB; 2011
Resumen:
Many bacteria produce the uptake systems for siderophores thatthey do not synthesize, allowing them to benefit from resourcesproduced by other bacteria. Under iron-limited conditions,Escherichia coli K-12 produces the catecholate siderophoreenterobactin in addition to the transport systems for a variety ofother siderophores. However, it is not known whether there is anuptake system for pyochelin, a pseudomonad siderophore. In thisreport, we analyzed the moderate toxicity we observed forpyochelin on E. coli. An E. coli enterobactin mutant (DentE) showedelevated sensitivity to pyochelin and this was reversed by additionof enterobactin. Surprisingly, iron supplementation did not have asimilar protective effect, ruling out iron starvation as an inhibitorymechanism. Addition of pyochelin to entE E. coli increased levels ofreactive oxygen species (ROS), which were lowered in the presenceof exogenous enterobactin and ascorbic acid. In addition, weobserved that copper, but not iron or zinc, also reversed pyochelintoxicity. This reversal was not observed in a cueO background, thusimplicating the multicopper oxidase CueO in protection frompyochelin. Together, these results suggest that siderophores may beused by bacteria to exert physiological and environmental rolesother than iron acquisition