Chlamydomonas mutant hpm91 lacking PGR5 is a scalable and valuable strain for algal hydrogen (H2) production

Liu, P.; Ye, D.-M.; Chen, M.; Zhang, J.; Huang, X.-H.; Shen, L.-L.; Xia, K.-K.; Xu, X.-J.; Xu, Y.-C.; Guo, Y.-L.; Wang, Y.-C.; Huang, F.

doi:10.1101/2022.02.23.481610

bioRxiv · 10.1101/2022.02.23.481610

Chlamydomonas mutant hpm91 lacking PGR5 is a scalable and valuable strain for algal hydrogen (H2) production

Liu, P.·Ye, D.-M.·Chen, M.·Zhang, J.·Huang, X.-H.·Shen, L.-L.·Xia, K.-K.·Xu, X.-J.·Xu, Y.-C.·Guo, Y.-L.·Wang, Y.-C.·Huang, F.

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Abstract

Clean and sustainable H2 production is essential toward a carbon-neutral world. H2 generation by Chlamydomonas reinhardtii is an attractive approach for solar-H2 from H2O. However, it is currently not scalable because of lacking ideal strains. Here, we explore hpm91, a previously reported PGR5-deletion mutant with remarkable H2 production, that possesses numerous valuable attributes towards large-scale application and in-depth study issues. We show that hpm91 is at least 100-fold scalable (upto 10 liter) with H2 collection sustained for averagely 26 days and 7287 ml H2/10L-HPBR. Also, hpm91 is robust and active over the period of sulfur-deprived H2 production, most likely due to decreased intracellular ROS relative to wild type. Moreover, quantitative proteomic analysis revealed its features in photosynthetic antenna, primary metabolic pathways and anti-ROS responses. Together with success of new high-H2-production strains derived from hpm91, we highlight that hpm91 is a potent strain toward basic and applied research of algal-H2 photoproduction.

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Liu, P., Ye, D.-M., Chen, M., Zhang, J., Huang, X.-H., Shen, L.-L., Xia, K.-K., Xu, X.-J., Xu, Y.-C., Guo, Y.-L., Wang, Y.-C., Huang, F.. 2022-02-24. Chlamydomonas mutant hpm91 lacking PGR5 is a scalable and valuable strain for algal hydrogen (H2) production. https://doi.org/10.1101/2022.02.23.481610

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