Mycobacterium smegmatis gewinnt Energie durch die Oxidation von Wasserstoff. Ein internationales Forschungsteam zeige, dass der dafür verwendeten Hydrogenase Huc sogar der nur in Spuren vorhandene Was...

The development of hydrogenases capable of operating under oxygenic photosynthetic conditions remains a key challenge for sustainable biohydrogen production. In this study, we developed a series of chimeric NAD+-reducing [NiFe]-hydrogenases (SH) combining structural elements from the O2-tolerant SH of Cupriavidus necator (CnSH) and the ferredoxin-interacting SH of Synechocystis sp. PCC6803 (SynSH). By engineering chimeric HoxU and HoxF subunits, we developed constructs─MixSH, Ch-HoxEFSyn+UCn, and Ch-HoxUswapCTD─that successfully couple the CnHoxYH hydrogenase module to the SynHoxEFU reductase module while retaining O2 tolerance and enhancing interaction with reduced ferredoxin. The lithoautotrophic growth of C. necator confirmed the tolerance of these variants to O2, while activity assays in Synechocystis demonstrated partial hydrogenase function, including H2 consumption and fermentative H2 production. Notably, Ch-HoxEFSyn+UCn retained ferredoxin interaction despite lacking the [4Fe4S]U4 cluster, showing [2Fe2S]F2 in HoxF as a functional ferredoxin-binding site. Moreover, we achieved the artificial integration of a [2Fe2S] cluster into CnHoxF and identified the CnHoxF N-terminal domain as structurally and functionally analogous to SynHoxE. Although electron transfer efficiency and activity in Synechocystis remained limited, this work validates the modular engineering of [NiFe]-hydrogenases, uniting O2-tolerance with ferredoxin interaction and offering a foundational step toward photosynthesis-coupled H2 production.

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Peer review is widely viewed as a critical aspect of biomedical communication. Ideally, it provides authors with feedback so they can improve manuscripts and gives readers, particularly nonspecialists...

H2 is an ideal energy vector, but catalysts for its clean production from water are inefficient or expensive. [FeFe]-hydrogenases are the most active H2-converting catalysts in nature, using a unique ...

The evolutionary role of adenosine monophosphate (AMP) in cofactors like NAD remains poorly understood. Here, the authors reveal that the AMP moiety protects NAD from overreduction in hydrothermal and...

The active-site iron of an H2-sensing [NiFe]-hydrogenase was selectively labeled with 57Fe, allowing the probing of all catalytic intermediates using synchrotron-based nuclear resonance vibrational sp...