Metagenomics-guided analysis of microbial chemolithoautotrophic phosphite oxidation yields evidence of a seventh natural CO2 fixation pathway.
Proc Natl Acad Sci U S A
; 115(1): E92-E101, 2018 01 02.
Article
em En
| MEDLINE
| ID: mdl-29183985
ABSTRACT
Dissimilatory phosphite oxidation (DPO), a microbial metabolism by which phosphite (HPO32-) is oxidized to phosphate (PO43-), is the most energetically favorable chemotrophic electron-donating process known. Only one DPO organism has been described to date, and little is known about the environmental relevance of this metabolism. In this study, we used 16S rRNA gene community analysis and genome-resolved metagenomics to characterize anaerobic wastewater treatment sludge enrichments performing DPO coupled to CO2 reduction. We identified an uncultivated DPO bacterium, Candidatus Phosphitivorax (Ca. P.) anaerolimi strain Phox-21, that belongs to candidate order GW-28 within the Deltaproteobacteria, which has no known cultured isolates. Genes for phosphite oxidation and for CO2 reduction to formate were found in the genome of Ca. P. anaerolimi, but it appears to lack any of the known natural carbon fixation pathways. These observations led us to propose a metabolic model for autotrophic growth by Ca. P. anaerolimi whereby DPO drives CO2 reduction to formate, which is then assimilated into biomass via the reductive glycine pathway.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
2_ODS3
Base de dados:
MEDLINE
Assunto principal:
Esgotos
/
Microbiologia da Água
/
Dióxido de Carbono
/
Fosfitos
/
Deltaproteobacteria
/
Crescimento Quimioautotrófico
/
Metagenômica
/
Águas Residuárias
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2018
Tipo de documento:
Article