Hydrogen (H₂) is a promising future chemical energy carrier and feedstock with several renewable production options, including electrolyzers and biological/bioinspired systems. The top H₂ producers in nature are [FeFe]-hydrogenases, high turnover metalloenzymes with a complex maturation process that can be circumvented by artificial synthetic activation. Here, we report the expression and activation of group A and D [FeFe]-hydrogenases in a photosynthetic host organism, the unicellular cyanobacterium Synechocystis PCC 6803. The hydrogenase from Solobacterium moorei (group A) facilitates high in vivo H₂ production from purely photoautotrophically generated substrates and unmistakably links to the metabolism of the photosynthetic host. Cells harboring the non-native, semisynthetic enzyme retain their H₂ production capacity for several days after synthetic activation. This work expands both the number and the diversity of [FeFe]-hydrogenases examined in a photosynthetic background and provides important insights for future investigations into the development and understanding of biological and biohybrid H₂ production systems.

氢（H ₂）是一种有前途的未来化学能源载体和原料，具有多种可再生生产选择，包括电解槽和生物/生物启发系统。自然界中最主要的H ₂生产者是[FeFe]氢化酶，这是一种高周转的金属酶，具有复杂的成熟过程，可以通过人工合成激活来避免。在这里，我们报道在光合宿主生物单细胞蓝藻集胞藻PCC 6803中A和D组[FeFe]氢化酶的表达和激活。Moorei梭菌（A组）的氢化酶促进体内高H _{2的表达。}由纯光养自生的底物生产，并且毫无疑问地与光合宿主的新陈代谢联系在一起。带有非天然半合成酶的细胞在合成激活后可保留其H ₂生产能力数天。这项工作扩大了在光合作用背景下所研究的[FeFe]氢化酶的数量和多样性，并为进一步研究和发展生物和生物杂交H ₂生产系统提供了重要的见解。