Metabolic Performance and Fate of Electrons during Nitrate-Reducing Fe(II) Oxidation by the Autotrophic Enrichment Culture KS Grown at Different Initial Fe/N Ratios.

ABSTRACT: Autotrophic nitrate-reducing Fe(II)-oxidizing (NRFeOx) microorganisms fix CO₂ and oxidize Fe(II) coupled to denitrification, influencing carbon, iron, and nitrogen cycles in pH-neutral, anoxic environments. However, the distribution of electrons from Fe(II) oxidation to either biomass production (CO₂ fixation) or energy generation (nitrate reduction) in autotrophic NRFeOx microorganisms has not been quantified. We therefore cultivated the autotrophic NRFeOx culture KS at different initial Fe/N ratios, followed geochemical parameters, identified minerals, analyzed N isotopes, and applied numerical modeling. We found that at all initial Fe/N ratios, the ratios of Fe(II)_oxidized to nitrate_reduced were slightly higher (5.11 to 5.94 at Fe/N ratios of

SUBMITTER: Huang J 

PROVIDER: S-EPMC10057050 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature