# Engineering a synthetic dual-organism system for hydrogen production.
> 水素生産を目的とした酵母と大腸菌の二生物系合成工学


## Abstract

This study investigated a two-organism synthetic system for biohydrogen production using renewable biomass. A formate-overproducing metabolic pathway was introduced into Saccharomyces cerevisiae by expressing pyruvate formate lyase, an anaerobic enzyme from Escherichia coli, enabling formate accumulation where wild-type yeast produced none. Co-expression of E. coli AdhE further increased formate output by 4.5-fold and improved growth rate and biomass yield. In a yeast strain with its formate degradation pathway deleted, an overall 18-fold elevation in formate production was achieved. As a proof-of-concept, E. coli was then used as a biocatalyst to convert the formate-rich medium into molecular hydrogen in a sequential two-step process. The findings suggest that S. cerevisiae could serve as a scalable platform for yeast-based biohydrogen generation with further optimization.

### Mechanism

Pyruvate formate lyase and AdhE expressed in yeast drive formate overproduction; E. coli formate hydrogen lyase then converts the accumulated formate into H2 and CO2 in a sequential catalytic step.

## Bibliographic

- **Authors**: Waks Z, Silver PA
- **Journal**: Appl Environ Microbiol
- **Year**: 2009
- **PMID**: [19201964](https://pubmed.ncbi.nlm.nih.gov/19201964/)
- **DOI**: [10.1128/AEM.02009-08](https://doi.org/10.1128/AEM.02009-08)
- **PMC**: [PMC2663214](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2663214/)
- **Study type**: other
- **Delivery route**: in vitro
- **Effect reported**: not assessed

## Delivery context

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 19201964. https://h2-papers.org/en/papers/19201964
> **Source**: PubMed PMID [19201964](https://pubmed.ncbi.nlm.nih.gov/19201964/)