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Functional cooperation of the glycine synthase-reductase and Wood-Ljungdahl pathways for autotrophic growth of Clostridium drakei.

ABSTRACT: Among CO2-fixing metabolic pathways in nature, the linear Wood-Ljungdahl pathway (WLP) in phylogenetically diverse acetate-forming acetogens comprises the most energetically efficient pathway, requires the least number of reactions, and converts CO2 to formate and then into acetyl-CoA. Despite two genes encoding glycine synthase being well-conserved in WLP gene clusters, the functional role of glycine synthase under autotrophic growth conditions has remained uncertain. Here, using the reconstructed genome-scale metabolic model iSL771 based on the completed genome sequence, transcriptomics, 13C isotope-based metabolite-tracing experiments, biochemical assays, and heterologous expression of the pathway in another acetogen, we discovered that the WLP and the glycine synthase pathway are functionally interconnected to fix CO2, subsequently converting CO2 into acetyl-CoA, acetyl-phosphate, and serine. Moreover, the functional cooperation of the pathways enhances CO2 consumption and cellular growth rates via bypassing reducing power required reactions for cellular metabolism during autotrophic growth of acetogens.

SUBMITTER: Song Y

PROVIDER: S-EPMC7132306 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Functional cooperation of the glycine synthase-reductase and Wood-Ljungdahl pathways for autotrophic growth of Clostridium drakei.

Song Yoseb Y Lee Jin Soo JS Shin Jongoh J Lee Gyu Min GM Jin Sangrak S Kang Seulgi S Lee Jung-Kul JK Kim Dong Rip DR Lee Eun Yeol EY Kim Sun Chang SC Cho Suhyung S Kim Donghyuk D Cho Byung-Kwan BK

Proceedings of the National Academy of Sciences of the United States of America 20200313 13

Among CO2-fixing metabolic pathways in nature, the linear Wood-Ljungdahl pathway (WLP) in phylogenetically diverse acetate-forming acetogens comprises the most energetically efficient pathway, requires the least number of reactions, and converts CO2 to formate and then into acetyl-CoA. Despite two genes encoding glycine synthase being well-conserved in WLP gene clusters, the functional role of glycine synthase under autotrophic growth conditions has remained uncertain. Here ...[more]

PMID: 32170009

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Dataset Information

Functional cooperation of the glycine synthase-reductase and Wood-Ljungdahl pathways for autotrophic growth of Clostridium drakei.

Publications

Functional cooperation of the glycine synthase-reductase and Wood-Ljungdahl pathways for autotrophic growth of <i>Clostridium drakei</i>.

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