Module II - Carbon Dioxide (CO₂) Fixation

Overview

RuBisCO

Carboxysome

Calvin-Cycle

Measurement

Outlook

The particular aim of the second module is to implement the carbon dioxide fiaxtion in E. coli. For this approach all items, like the sedoheptulose-1,7-bisphosphatase, the ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and the mechanism of carbon dioxide fixation were tested separetly in various approaches. For the optimization of the carbon dioxide fixation under aerobic growth conditions we investigate the anerobic microcompartment from Halothiobacillus neapolitanus, called the carboxysom.

Figure 1: Schematic representation of the Calvin cylce. The reactions shown in green can be catalyzed by enzymes that naturally exist in E. coli, while the red ones need to be expressed heterologous to enable the whole Calvin cycle in E. coli.

For this purpose we made different approaches. First of all we identified two RuBisCOs (from H. neapolitanus and from Synechococcus elongatus) as the most efficient and best fitting ones. There coding sequences were synthesized to remove illegal restriction sites and to optimize the codong usage for the heterologous expression in E. coli. These enzymes are known to function best inside a carboxysome. Therefore we started the construction of such a microcompartment in E. coli.
To achieve the carbon dioxide fixation by applying synthetic biology a bottom up approach was used. The isolated parts were characterized and combined to larger constructs afterwards.

Team:Bielefeld-CeBiTec/Results/CO2-fixation

From 2014.igem.org

Module II - Carbon Dioxide (CO2) Fixation

Module II - Carbon Dioxide (CO₂) Fixation