Flavin-Dependent NADH Dehydrogenase-Mimetic Materials Facilitating Bioinspired Electron Transfer Chain

Flavoenzymes play pivotal roles in biological electron transport chains, yet replicating their functions synthetically remains challenging. Here, we report the assembly of a flavin mononucleotide (FMN) with lysine-rich peptides to form a flavin-containing catalyst, which mimics the catalytic function of NADH dehydrogenase (NDH) by oxidizing NADH and undergoing FMN reduction. Lysine residues create a conducive microenvironment, promoting the proximity of FMN and NADH and their hydride transfer. The resulting FMNH – facilitates sequential cytochrome c and enzymatic oxygen reduction, while NADH regenerates from enzymatic glucose dehydrogenation, akin to specific cellular respiration steps. Thus, the synthetic flavoenzyme emulates protein complex I. Lysine peptides aid in spatially organizing FMN, cytochrome c, and glucose dehydrogenase. Stability experiments reveal the resilience of the catalyst to temperatures up to 85 °C with recyclability when immobilized on a polymer support. These findings inform the design of biomimetic catalytic materials for bioinspired processes, offering insights into prebiotic protein complex models.