Characterization of a ferric uptake regulator (Fur)-mutant of the cyanotrophic bacterium Pseudomonas pseudoalcaligenes CECT5344.

•The fur mutant accumulates more iron than the wild type strain of Pseudomonas pseudoalcaligenes CECT5344.•Pseudomonas pseudoalcaligenes CECT5344 does not produce siderophores detectable by the CAS-agar method.•The presence of cyanide generates an intracellular signal equivalent to iron deprivation.•The fur mutant is extremely susceptible to cyanide toxicity in LB medium.•The fur mutant is impaired in defense mechanism against ROS, as shown by an increased sensitivity to paraquat and menadione.