Cadmium and Copper Cross-Tolerance. Cu⁺ Alleviates Cd^{2 +} Toxicity, and Both Cations Target Heme and Chlorophyll Biosynthesis Pathway in Rubrivivax gelatinosus.

ABSTRACT: Cadmium, although not redox active is highly toxic. Yet, the underlying mechanisms driving toxicity are still to be characterized. In this study, we took advantage of the purple bacterium Rubrivivax gelatinosus strain with defective Cd^{2 +}-efflux system to identify targets of this metal. Exposure of the ΔcadA strain to Cd^{2 +} causes a decrease in the photosystem amount and in the activity of respiratory complexes. As in case of Cu⁺ toxicity, the data indicated that Cd^{2 +} targets the porphyrin biosynthesis pathway at the level of HemN, a S-adenosylmethionine and CxxxCxxC coordinated [4Fe-4S] containing enzyme. Cd^{2 +} exposure therefore results in a deficiency in heme and chlorophyll dependent proteins and metabolic pat

SUBMITTER: Steunou AS 

PROVIDER: S-EPMC7283390 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature