Postdoctoral Fellow

During photosynthesis, plants turn water and carbon dioxide into oxygen and sugar. A key player in this process is the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) which catalyzes the conversion of atmospheric carbon dioxide to sugar molecules and amino acids that then serve as the building material for cells and tissues. The most abundant form (form I) of Rubisco, found in plants, algae, cyanobacteria and proteobacteria, has a hexadecameric structure consisting of eight large (RbcL) and eight small (RbcS) subunits. Recent investigations have shown that the RbcL subunit, after folding by the chaperonin system, requires auxiliary factors for assembly and functional maintenance. To date, a cyanobacterial Rubisco has been reconstituted, with some efficiency, using the E. coli chaperonin system, GroEL and GroES, and the recently discovered assembly chaperone RbcX. However, all attempts to reconstitute the plant Rubisco in vitro have failed so far. Using a broad range of methods, from the areas of structural biology, biochemistry, molecular and cell biology, this project aims to understand the mechanism by which RbcX and other auxiliary factors interact with the RbcL and/or RbcS subunits of Rubisco. The final goal would be to reconstitute the plant Rubisco in vitro using all purified components. Once the necessary components are defined, recombinant expression in bacteria should pave the way for detailed mutagenesis of Rubisco and possible engineering of more efficient enzymes.

The position is an MPIB fellowship for 1 year with the possibility to extend to a maximum of 4 years. The applicant is expected to be well versed in protein expression, purification and standard protein biochemistry. Experience with measuring photosynthetic parameters and plant tissue culture would be advantageous.