RRC ID 66201
著者 Steunou AS, Babot M, Bourbon ML, Tambosi R, Durand A, Liotenberg S, Krieger-Liszkay A, Yamaichi Y, Ouchane S.
タイトル Additive effects of metal excess and superoxide, a highly toxic mixture in bacteria.
ジャーナル Microb Biotechnol
Abstract Heavy metal contamination is a serious environmental problem. Understanding the toxicity mechanisms may allow to lower concentration of metals in the metal-based antimicrobial treatments of crops, and reduce metal content in soil and groundwater. Here, we investigate the interplay between metal efflux systems and the superoxide dismutase (SOD) in the purple bacterium Rubrivivax gelatinosus and other bacteria through analysis of the impact of metal accumulation. Exposure of the Cd2+ -efflux mutant ΔcadA to Cd2+ caused an increase in the amount and activity of the cytosolic Fe-Sod SodB, thereby suggesting a role of SodB in the protection against Cd2+ . In support of this conclusion, inactivation of sodB gene in the ΔcadA cells alleviated detoxification of superoxide and enhanced Cd2+ toxicity. Similar findings were described in the Cu+ -efflux mutant with Cu+ . Induction of the Mn-Sod or Fe-Sod in response to metals in other bacteria, including Escherichia coli, Pseudomonas aeruginosa, Pseudomonas putida, Vibrio cholera and Bacillus subtilis, was also shown. Both excess Cd2+ or Cu+ and superoxide can damage [4Fe-4S] clusters. The additive effect of metal and superoxide on the [4Fe-4S] could therefore explain the hypersensitive phenotype in mutants lacking SOD and the efflux ATPase. These findings underscore that ROS defence system becomes decisive for bacterial survival under metal excess.
巻・号 13(5)
ページ 1515-1529
公開日 2020-9-1
DOI 10.1111/1751-7915.13589
PMID 32558268
PMC PMC7415354
MeSH Burkholderiales* Metals, Heavy* Superoxide Dismutase / genetics Superoxides
IF 5.328
リソース情報
原核生物(大腸菌) Keio collection JW0473-KC JW3434-KC JW3879-GE JW1648-KC