Illuminating the Potential: Light Harvesting and Semiconducting Properties of Bacterial Microcompartment Shell Proteins

Bedi, S.; Rose, S. M.; Sinha, S.

doi:10.1101/2024.12.16.628711

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bioRxiv · 10.1101/2024.12.16.628711

Illuminating the Potential: Light Harvesting and Semiconducting Properties of Bacterial Microcompartment Shell Proteins

Bedi, S.·Rose, S. M.·Sinha, S.

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Abstract

Biomaterials with self-assembly, genetic tunability, self-healing, and biocompatibility hold promise for next-generation electronics. This study explores disc-like shell proteins from bacterial microcompartments as photovoltaic materials. These self-assembling proteins exhibit semiconducting properties, including a low work function and non-linear I-V behavior. Notably, under UV light, they generate significant photocurrent without external voltage, demonstrating efficient electron transfer. Electron conduction occurs via tunneling, enabled by distinct electron-rich surface regions. High responsivity and quantum efficiency outperform prior protein-based systems, emphasizing their potential in photocurrent and light-harvesting applications. Genetic mutations revealed a proton-coupled electron transfer (PCET) mechanism, where tyrosine residues strategically positioned near proton abstraction sites enhance photocurrent generation. This study highlights the innovative capabilities of shell proteins for energy-efficient devices and demonstrates how genetic engineering can further optimize biomaterial performance, paving the way for sustainable electronic applications.

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Bedi, S., Rose, S. M., Sinha, S.. 2024-12-20. Illuminating the Potential: Light Harvesting and Semiconducting Properties of Bacterial Microcompartment Shell Proteins. https://doi.org/10.1101/2024.12.16.628711

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