  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.
