biostudies-literatureUnknown11Steunou ASCadmium, 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 <i>Rubrivivax gelatinosus</i> strain with defective Cd^{2 +}-efflux system to identify targets of this metal. Exposure of the Δ<i>cadA</i> 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 <i>S</i>-adenosylmethionine and CxxxCxxC coordinated [4Fe-4S] containing enzyme. Cd^{2 +} exposure therefore results in a deficiency in heme and chlorophyll dependent proteins and metabolic patFrontiers in microbiology893https://www.ebi.ac.uk/biostudies/studies/S-EPMC7283390biostudies-literatureCadmium and Copper Cross-Tolerance. Cu⁺ Alleviates Cd^{2 +} Toxicity, and Both Cations Target Heme and Chlorophyll Biosynthesis Pathway in <i>Rubrivivax gelatinosus</i>.PMC7283390Ouchane SSteunou ASDurand ABourbon MLLiotenberg SBabot MTambosi RfalseCadmium and Copper Cross-Tolerance. Cu⁺ Alleviates Cd^{2 +} Toxicity, and Both Cations Target Heme and Chlorophyll Biosynthesis Pathway in <i>Rubrivivax gelatinosus</i>.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 <i>Rubrivivax gelatinosus</i> strain with defective Cd^{2 +}-efflux system to identify targets of this metal. Exposure of the Δ<i>cadA</i> 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 <i>S</i>-adenosylmethionine and CxxxCxxC coordinated [4Fe-4S] containing enzyme. Cd^{2 +} exposure therefore results in a deficiency in heme and chlorophyll dependent proteins and metabolic pat2020-01-01T00:00:00Z20202025-06-01T03:00:36.736Z2025-06-01T03:00:36.736ZS-EPMC72833903258204110.3389/fmicb.2020.00893