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Updated: Dec 31, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Exploring Chloride Selectivity and Halogenase Regioselectivity of the SalL Enzyme through Quantum
Paulo R M Pereira1, Jéssica de O Araújo1, José Rogério A Silva1
1Laboratório de Planejamento e Desenvolvimento de Fármacos, Instituto de Ciências Exatas e Naturais , Universidade Federal do Pará , 66075-110 , Belém , PA , Brasil.
Abstract:
The catalytic mechanism of SalL chlorinase has been investigated by combining quantum mechanical/molecular mechanical (QM/MM) techniques and umbrella sampling simulations to compute free energy profiles. Our results shed light on the interesting fact that the substitution of chloride with fluorine in SalL chlorinase leads to a loss of halogenase activity. The potential of mean force based on DFTB3/MM analysis shows that fluorination corresponds to a barrier 13.5 kcal·mol-1 higher than chlorination. Additionally, our results present a molecular description of SalL acting as a chlorinase instead of a methyl-halide transferase.
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