[Donaldson Tan]

Yggdrasil:

Do you think it is possible to construct a RuBisCO-based CO₂ capturing system using an O₂ screen to prevent cross reaction with oxygen? Any chance that the gene that produces the RuBisCO enzyme can be engineered to be heat resistant? After-all, we do have heat resistant enzymes. What is the stoichiometeric ratio between RuBisCO enzyme and CO₂?

[wereworm73]

There's also the matter of continuously supplying the enzyme with ribulose-1,5-bisphosphate.  The enzyme breaks it down into 3-phosphoglycerate, and there's a whole bunch of steps in the Calvin-Benson cycle before it's converted back into ribulose-1,5-bisphosphate again.   Given the harsh industrial conditions, is there any economically feasible way of converting the 3-phosphoglycerate product back into ribulose-1,5-bisphosphate? 

[Yggdrasil]

Yggdrasil:

Do you think it is possible to construct a RuBisCO-based CO₂ capturing system using an O₂ screem to prevent cross reaction with oxygen? Any chance that the gene that produces the RuBisCO enzyme can be engineered to be heat resistant? After-all, we do have heat resistant enzymes. What is the stoichiometeric ratio between RuBisCO enzyme and CO_2?

A paper came out recently stating that the apparently wasteful oxygenation by most Rubisco enzymes is a result of their attempts to balance catalytic efficiency against affinity for carbon dioxide over oxygen.

"We assert that all Rubiscos may be nearly perfectly adapted to the differing CO2, O2, and thermal conditions in their subcellular environments, optimizing this compromise between CO2/O2 specificity and the maximum rate of catalytic turnover."

See Tcherkez et al. (2006) PNAS 103: 7246-7251. 
http://www.pnas.org/cgi/content/full/103/19/7246  (subscription required)

I'm not too knowledgable about protein engineering, but I'm not sure whether heat resistant enzymes have been engineered.  There are heat resistant enzymes (e.g. Taq polymerase), but these enzymes were isolated from thermophilic bacteria.