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Requirements for Efficient Thiosulfate Oxidation in Bradyrhizobium diazoefficiens.

ABSTRACT: One of the many disparate lifestyles of Bradyrhizobium diazoefficiens is chemolithotrophic growth with thiosulfate as an electron donor for respiration. The employed carbon source may be CO? (autotrophy) or an organic compound such as succinate (mixotrophy). Here, we discovered three new facets of this capacity: (i) When thiosulfate and succinate were consumed concomitantly in conditions of mixotrophy, even a high molar excess of succinate did not exert efficient catabolite repression over the use of thiosulfate. (ii) Using appropriate cytochrome mutants, we found that electrons derived from thiosulfate during chemolithoautotrophic growth are preferentially channeled via cytochrome c₅₅₀ to the aa?-type heme-copper cytochrome oxidase. (iii) Three genetic regulators were identified to act at least partially in the expression control of genes for chemolithoautotrophic thiosulfate oxidation: RegR and CbbR as activators, and SoxR as a repressor.

SUBMITTER: Masuda S

PROVIDER: S-EPMC5748708 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Requirements for Efficient Thiosulfate Oxidation in Bradyrhizobium diazoefficiens.

Masuda Sachiko S Hennecke Hauke H Fischer Hans-Martin HM

Genes 20171215 12

One of the many disparate lifestyles of <i>Bradyrhizobium diazoefficiens</i> is chemolithotrophic growth with thiosulfate as an electron donor for respiration. The employed carbon source may be CO₂ (autotrophy) or an organic compound such as succinate (mixotrophy). Here, we discovered three new facets of this capacity: (i) When thiosulfate and succinate were consumed concomitantly in conditions of mixotrophy, even a high molar excess of succinate did not exert efficient catabolite repression ove ...[more]

PMID: 29244759

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Dataset Information

Requirements for Efficient Thiosulfate Oxidation in Bradyrhizobium diazoefficiens.

Publications

Requirements for Efficient Thiosulfate Oxidation in Bradyrhizobium diazoefficiens.

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