The Catalytic Mechanism of the Retaining Glycosyltransferase Mannosylglycerate Synthase.

To protect their intracellular proteins, extremophile microorganisms synthesize molecules called compatible solutes. These molecules are the result of the attachment of a small negatively charged molecule to a sugar molecule. It has been found that these molecules, not only protect the microorganism against osmotic stress but also against other extreme conditions. They can also confer protection against extreme conditions to isolated enzymes from different organisms making them an exciting prospect for potential biotechnological applications. One of the most widespread compatible solute in hyperthermophile organisms is the molecule 2-O-α-D-mannosyl-D-glycerate (MG). In addition to confer protection to proteins against extreme conditions, MG was found to prevent Alzheimer's β-amyloid aggregation and reduce α-synuclein fibril formation in Parkinson's disease. In this work we studied, using computational methods, the catalytic mechanism of the synthesis of MG by the enzyme mannosylglycerate synthase (MGS) from the thermophilic bacteria Rhodothermus marinus.