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bioRxiv · 10.1101/2023.05.03.539223

Chlamydomonas reinhardtii and Microbacterium fakhimi sp. nov., a mutualistic association that favor sustainable hydrogen production.

Fakhimi, N.·Dubini, A.·Torres, M. J.·Fernandez, E.·Galvan, A.·Gonzalez-Ballester, D.
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Abstract

A multispecies bacterial community including Microbacterium forte sp. nov., Stenotrophomonas goyi sp. nov., and Bacillus cereus greatly promoted sustained hydrogen production by the microalga Chlamydomonas reinhardtii when cocultivated in mannitol- and yeast extract-containing medium (up to 313 mL{middle dot}L-1). Alga viability was also largely prolonged in the cocultures (>45 days) without any nutrient supplementation. Among the bacterial community, Microbacterium forte sp. nov. was the main responsible for the hydrogen production improvement. Nonetheless, the use of the entire bacterial community allowed a better growth of the alga during hydrogen production. Chlamydomonas reinhardtii and Microbacterium forte sp. nov. established a mutualistic association, based on the release of ammonium and acetic acid from the bacterium, while the alga provided sulfur-containing metabolites and complemented the bacterial auxotrophy for biotin and thiamine. This study uncovers the potential of the Chlamydomonas-bacteria consortia for durable and stable H2 production while allowing the simultaneous production of biomass.

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Fakhimi, N., Dubini, A., Torres, M. J., Fernandez, E., Galvan, A., Gonzalez-Ballester, D.. 2023-05-03. Chlamydomonas reinhardtii and Microbacterium fakhimi sp. nov., a mutualistic association that favor sustainable hydrogen production.. https://doi.org/10.1101/2023.05.03.539223

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