The second module we aim to use a carboxysome of cyanobacteria or purple sulfurbacteria. With this we want to create a Calvin-Benson cycle in E.coli. In addition we would like to compare the efficiency of the carboxysome with a free RuBisCO (Ribulose-1,5-bisphosphate-carboxylase-oxygenase), the 3-Hydroxypropionate cycle or other types of carboxysomes. The product of the fixation will be pyruvate which can be used for production of different metabolites like for example Isobutanol.