Predicting Rubisco:Linker Condensation from Titration in the Dilute Phase

Alex Payne-Dwyer; Gaurav Kumar; James Barrett; Laura K. Gherman; Michael Hodgkinson; Michael Plevin; Luke Mackinder; Mark C. Leake; Charley Schaefer

arXiv · 2301.05681

Predicting Rubisco:Linker Condensation from Titration in the Dilute Phase

Alex Payne-Dwyer·Gaurav Kumar·James Barrett·Laura K. Gherman·Michael Hodgkinson·Michael Plevin·Luke Mackinder·Mark C. Leake·Charley Schaefer

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Abstract

The condensation of Rubisco holoenzymes and linker proteins into 'pyrenoids', a crucial super-charger of photosynthesis in algae, is qualitatively understood in terms of 'sticker-and-spacer' theory. We derive semi-analytical partition sums for small Rubisco:linker aggregates, which enable the calculation of both dilute-phase titration curves and dimerisation diagrams. By fitting the titration curves to Surface Plasmon Resonance and Single-Molecule Fluorescence Microscopy data, we extract the molecular properties needed to predict dimerisation diagrams. We use these to estimate typical concentrations for condensation, and successfully compare these to microscopy observations.

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Alex Payne-Dwyer, Gaurav Kumar, James Barrett, Laura K. Gherman, Michael Hodgkinson, Michael Plevin, Luke Mackinder, Mark C. Leake, Charley Schaefer. 2023-01-13. Predicting Rubisco:Linker Condensation from Titration in the Dilute Phase. https://arxiv.org/abs/2301.05681

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