ENTEROBACTIN: A FENTON-SAFE SIDEROPHORE

PERALTA D; ADLER, C.; CORBALAN , N.; PAZ GARCÍA EC; POMARES, M.F.; VINCENT ,P A.

Córdoba

Congreso; 52 th Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

There is increasing evidence that siderophores may play alternative roles, aside of providing cells with the necessary iron. Wepreviously reported that the catechol siderophore enterobactin, is crucial forEscherichia colicolony development in culture conditionsthat increased the oxidative stress. In this work, we demonstrated that enterobactin confers protection against various sources ofoxidative stress such us H2O2, paraquat and copper, independently of its ability to facilitate iron uptake. Protection against oxidativestress occurs in the cell cytoplasm through ROS scavenging and requires prior hydrolysis of the enterobactin molecule. Interestingly,both the sensitivity to stressors and the colony development arrest phenotype were enhanced when cells harbored theentE mutationalong with eithersodAorkatG. Confirming the link between enterobactin and oxidative stress, we found that enterobactin transcriptionalexpression and production was induced by oxidative stressors even in the presence of iron. Furthermore, preliminary data indicatesthat enterobactin transcription would be regulated by oxidative stress through the global regulator SoxS. These results strongly supportthe involvement of enterobactin as part of the oxidative stress response ofE. coli.