Overview mechanisms of bacterial antimonite resistance and oxidation. (A) A hypothetical model of IscR's regulation of bacterial Sb(III) oxidation. (i) Sb(III) induced the production of H 2 O 2 via the bacterial oxidative stress response and subsequently H 2 O 2 oxidized Sb(III) to Sb(V). (ii) H 2 O 2 was partially consumed by catalase KatA. (iii) Sb(III) induced the expression of [Fe-S] assembly transcription factor IscR, which could positively contribute to GSH formation. Then, H 2 O 2 was partially consumed by GSH. (B) Cellular events are represented on this model according to the published literature. Sb(III) is taken up through glycerol channel and extruded from the cell by Acr3 and ArsAB, and transportation of Sb(V) remains unknown. Bacteria obtained Sb(III) resistance by the ars operon. In addition, Sb(III) oxidation, Sb(V) reduction, and Sb(III) methylation were also involved in bacterial Sb detoxification. For energy generation, Sb(III) could induce activation of the TCA cycle and produce energy to against the toxicity of Sb.  

Overview mechanisms of bacterial antimonite resistance and oxidation. (A) A hypothetical model of IscR's regulation of bacterial Sb(III) oxidation. (i) Sb(III) induced the production of H 2 O 2 via the bacterial oxidative stress response and subsequently H 2 O 2 oxidized Sb(III) to Sb(V). (ii) H 2 O 2 was partially consumed by catalase KatA. (iii) Sb(III) induced the expression of [Fe-S] assembly transcription factor IscR, which could positively contribute to GSH formation. Then, H 2 O 2 was partially consumed by GSH. (B) Cellular events are represented on this model according to the published literature. Sb(III) is taken up through glycerol channel and extruded from the cell by Acr3 and ArsAB, and transportation of Sb(V) remains unknown. Bacteria obtained Sb(III) resistance by the ars operon. In addition, Sb(III) oxidation, Sb(V) reduction, and Sb(III) methylation were also involved in bacterial Sb detoxification. For energy generation, Sb(III) could induce activation of the TCA cycle and produce energy to against the toxicity of Sb.  

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Antimony (Sb) is a toxic metalloid that occurs widely at trace concentrations in soil, aquatic systems, and the atmosphere. Nowadays, with the development of its new industrial applications and the corresponding expansion of antimony mining activities, the phenomenon of antimony pollution has become an increasingly serious concern. In recent years,...

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... (i) Sb(III) can induce the bacterial oxidative stress response, leading to the pro- duction of H 2 O 2 ; (ii) the induced H 2 O 2 oxidizes Sb(III) to Sb(V) under alkaline conditions; and (iii) IscR is involved in the regula- tion of GSH formation. Then, H 2 O 2 is consumed by KatA and GSH, which might also affect bacterial Sb(III) oxidation (Fig. 4A). Although there are other regulators of the bacterial oxidative re- sponse, such as the Mer-like redox sensor SoxR and the LysR regulator OxyR (131), their function(s) with respect to Sb(III) oxidation has not been ...
Context 2
... review highlights the recent advances in our understanding of microbial Sb transformations (Fig. 4B). Due to the similar chemical characteristics between As and Sb, the biochemical path- ways of Sb(III) oxidation as well as the pathway for dissimilatory Sb(V) reduction were predicted to be shared with As(III) and As(V). However, based on recent literature and our published work, we propose that microbial Sb transformation proceeds by ...

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