A stepwise docking and molecular dynamics approach for enzymatic biolubricant production using Lipase Eversa® Transform as a biocatalyst

Biolubricants have gained a notable market share in the last decade due to the increased interest in replacing petroleum-based lubricants in various applications. Biolubricants are produced by using renewable raw materials such as vegetable oils, and enzymes such as lipases. The latter can be used as catalysts for biolubricant synthesis, which renders these processes environmentally friendly. Among the several innovations enabled by enzymatic engineering tools, the lipase Eversa® Transform 2.0 stands out as a genetically-modified and low-cost enzymatic formulation that has shown high activity in the production of biodiesel, fatty acids, and biolubricants. In addition to enzymatic engineering, advanced computational tools, such as docking and molecular dynamics, can also be powerful allies in the development of competitive products that impart low negative impact in the environment. These simulation tools enable the elucidation and understanding of reaction mechanisms, cut reagent costs, and inform choices regarding materials and conditions to be used in related industrial processes. Thus being, this work proposed the analysis and modeling of the synthesis reactions of biolubricants derived from oleic acid via the use of n-octanol and isoamyl alcohol, with lipase Eversa® Transform 2.0. Molecular dockings showed that the predominant interactions between the ligands and the amino acid residues that make up the active site of the enzyme and its surroundings were of Van der Waals and hydrophobic nature. Through simulations via molecular dynamics, it was found that these interactions were responsible for the stability of the lipase-ligand complex, given the low number of hydrogen bonds formed during the simulations. Furthermore, the low variation in the position of the lipase-ligand complexes comparatively to their initial conformations over the production stages attested that the chosen docking poses were adequate to describe the ligand conformations in the region of the active sites of the enzyme. These results also provide a structural view of the interactions between lipase Eversa® and the fatty esters used as lubricants, and confirm the potential in the use of these alcohols in this process. Finally, an in vitro validation showed improved results of esterification activity of the lipase with isoamyl alcohol. This hinted that the substrate that was in closer conformation and that showed shorter and more stable hydrogen bonds with the active sites of the enzyme demonstrated better use potential for the biolubricant production system that has been proposed.