A conditional upper-bound design map for rhodopsin-augmented electro microbial CO2-to-biomass conversion
- 1University of Oxford
Abstract
The value of rhodopsin proton pumps as light harvesters in electro-microbial CO2-to-biomass conversion depends on molecular photophysics, pathway energetics and reactor light delivery. We couple these scales for Cupriavidus necator, comparing Calvin-Benson-Bassham (CBB) and reductive glycine (rGlyP) assimilation. The model predicts a 17.9% dark rGlyP yield advantage, close to 16.5% measured in chemostats. At 568 nm, 100 PPFD and 45% membrane occupancy, light-derived ATP raises yield by 17% for rGlyP and 14% for CBB. Charging CO2 capture and formate electrosynthesis, a retinal-only reactor reaches 3.29% efficiency versus 2.56% in the dark. A carotenoid antenna raises this to 3.52% at the model-derived 70% transfer estimate and helps in 93.2% of uncertainty samples, but lowers efficiency at the thermodynamic limit by diverting photons from photovoltaics. Point-source CO2 cuts the relative light benefit from 38% to 8%. Rhodopsin is therefore most useful when upstream formate is energy-intensive, not as a general efficiency boost.
Related
- Effects of Alternating Polarity Frequency on the Assembly of Electro-Methanogenic Microbial Communities
- Enhancing Carbon Conversion Efficiency and Product Yield Through Systematic Biocatalyst Design for Microbial Electrosynthesis
- One-step microbial conversion of waste molasses into bioactive fulvic-like acid fertilizer for sustainable soil quality improvement and agricultural waste valorization
- Mechanistic Insights into MYO1C-Mediated Rhodopsin Trafficking and Rod Photoreceptor Homeostasis.
- A Tandem Fluorescent Rh1::eGFP mCherry Reporter Reveals Rhodopsin 1 Trafficking and Turnover In Vivo in Drosophila Photoreceptors
BibTeX
@misc{saeed2026conditional,
title = {{A conditional upper-bound design map for rhodopsin-augmented electro microbial CO2-to-biomass conversion}},
author = {H. Saeed and W. Huang and A. Yang},
howpublished = {bioRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.09.758023},
url = {https://www.biorxiv.org/content/10.64898/2026.10.09.758023v1},
note = {CC BY-NC},
}
RIS
TY - UNPB
TI - A conditional upper-bound design map for rhodopsin-augmented electro microbial CO2-to-biomass conversion
AU - H. Saeed
AU - W. Huang
AU - A. Yang
PY - 2026
DA - 2026/10/09
PB - bioRxiv
DO - 10.64898/2026.10.09.758023
UR - https://www.biorxiv.org/content/10.64898/2026.10.09.758023v1
AB - The value of rhodopsin proton pumps as light harvesters in electro-microbial CO2-to-biomass conversion depends on molecular photophysics, pathway energetics and reactor light delivery. We couple these scales for Cupriavidus necator, comparing Calvin-Benson-Bassham (CBB) and reductive glycine (rGlyP) assimilation. The model predicts a 17.9% dark rGlyP yield advantage, close to 16.5% measured in chemostats. At 568 nm, 100 PPFD and 45% membrane occupancy, light-derived ATP raises yield by 17% for rGlyP and 14% for CBB. Charging CO2 capture and formate electrosynthesis, a retinal-only reactor reaches 3.29% efficiency versus 2.56% in the dark. A carotenoid antenna raises this to 3.52% at the model-derived 70% transfer estimate and helps in 93.2% of uncertainty samples, but lowers efficiency at the thermodynamic limit by diverting photons from photovoltaics. Point-source CO2 cuts the relative light benefit from 38% to 8%. Rhodopsin is therefore most useful when upstream formate is energy-intensive, not as a general efficiency boost.
ER -