Synthetic gas (syngas) is an alternative source of energy to paliate¬¬¬¬ the coming fossil fuel shortage. Syngas can be converted into synthetic fuels or commodity products, using the reaction of water gaz shift reaction. Some Hydrogenic carboxydotrophic bacteria e.g. Carboxydothermus hydrogenoformans are able to use CO as the sole energy source and provide Bio-WGSR. In this case, the reaction is catalyzed by a multienzyme complex: the oxidation of CO to CO2, catalyzed by a Nickel-dependent carbon monoxide dehydrogenase called CODH. In the case of ChCODH, little is known about the biogenesis of its catalytic site, except that nickel insertion is a key step in the enzyme activation. The crucial step of Ni atom insertion, known as CODH activation, requires two nickel-binding proteins: the nickel-dependent ATPase CooC and an additional nickel chaperones CooT. Our team is studying the maturation process of CODH for the optimization of bio-WGSR.