Publications by authors named "Sonia F G Santos"

Lignin, a complex plant cell wall component, holds promise as a renewable aromatic carbon feedstock. p-Vanillin is a key product of lignin depolymerization and a precursor of protocatechuic acid (PCA) that has tremendous potential for biofuel production. While the GcoAB enzyme, native to sp.

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A recently discovered heme-dependent enzyme tyrosine hydroxylase (TyrH) offers a green approach for functionalizing the high-strength C-H and C-F bonds in aromatic compounds. However, there is ambiguity regarding the nature of the oxidant (compound 0 or compound I) involved in activating these bonds. Herein, using comprehensive molecular dynamics (MD) simulations and hybrid quantum mechanical/molecular mechanical calculations, we reveal that it is compound I (Cpd I) that acts as the primary oxidant involved in the functionalization of both C-F and C-H bonds.

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Cytochrome P450 is an enzyme that catalyzes the guaiacol unit of lignin during the lignin breakdown via an aryl--demethylation reaction. This reaction is intriguing and is of commercial importance for its potential applications in the production of biofuel and plastic from biomass feedstock. Recently, the F169A mutation in P450 elicits a promiscuous activity for syringol while maintaining the native activity for guaiacol.

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The development of plant-based synthetic rennets is of high commercial interest, due to the current great consumer demand for animal product alternatives. A previously developed recombinant form of the aspartic protease cardosin B with a three-glycine linker showed great potential due to its good performance in milk coagulation. This enzyme was found to be more specific and less proteolytically active than the native form for milk clotting, but the underlying structural causes for these activity changes were not completely clear.

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