To carry out chemical reactions, life uses little energy and produces little waste, which is why green chemistry is seeking to draw inspiration from it to produce many molecules of industrial interest more efficiently and at lower cost.
To achieve this, laboratories are looking to exploit proteins, called metalloenzymes, which are catalysts capable of accelerating chemical reactions up to several million times. However, these metalloenzymes are not capable of catalyzing all the chemical reactions that lead to industrial products and they lack stability. That is why researchers have created artificial metalloenzymes by inserting a metallic inorganic catalyst into an inactive protein structure. The inorganic part then plays the role of the active site of the enzyme while its protein part provides the selectivity of the reaction.
Irig researchers have developed several metalloenzymes using a protein responsible for the transport of nickel in bacteria, to which they have anchored various inorganic complexes of iron, manganese or ruthenium. They then solidified these metalloenzymes using a special crystallization technique called "Cross Linking", which improved the stability of the catalytic site.
The crystalline metalloenzymes thus obtained were used to synthesize models of pharmaceutical industry molecules, such as sulfoxidation products of thioglycolamide derivatives, with an efficiency multiplied by 8 and in the presence of very small quantities of catalyst (0.1%). In addition, these metalloenzymes are capable of several cycles of catalysis under harsh conditions since the oxidant used, sodium hypochlorite, is very aggressive.
The contribution of these new crystalline metalloenzymes as bio-inspired catalysts are promising for the development of sustainable chemistry.