abstract
Enzymatic synthesis of polymeric materials is a powerful approach to make these processes greener, more economical, and safer for scale-up. Herein, we characterized new variants of the hyperthermophilic carboxylesterase from the archaeon Archaeoglobus fulgidus with quantum mechanics/molecular mechanics molecular dynamics simulations. The designed variants were expressed and tested for the synthesis of poly(e-caprolactone) and triblock poly(e-caprolactone)-poly(ethylene glycol), two important biomaterials. The reactant complexes of the best variants formed stronger hydrogen bonds with the nucleophilic oxygen and the subsequent tetrahedral intermediates formed stronger hydrogen bonds with the leaving lactone oxygen, reflecting the best active site preorganization for stabilization of the two consecutive transition states that involve the same active site machinery. Our findings set the underpinning ground to redesign other enzymes for polyesterification reactions.
keywords
RING-OPENING POLYMERIZATION; ARCHAEON ARCHAEOGLOBUS-FULGIDUS; ANTARCTICA LIPASE B; THERMOPHILIC ESTERASE; EPSILON-CAPROLACTONE; ALIPHATIC POLYESTERS; CRYSTAL-STRUCTURE; PCL; DYNAMICS; SYSTEM
subject category
Chemistry
authors
Almeida, BC; Figueiredo, PR; Dourado, DFAR; Paul, S; Sousa, AF; Silvestre, AJD; Quinn, DJ; Moody, TS; Carvalho, ATP
our authors
Andreia Fernandes de Sousa
Principal Researcher
Armando Jorge Domingues Silvestre
Full professor
Pedro R. Figueiredo
PhD Studentacknowledgements
The authors acknowledge the computing resources made available by the Minerva HPC from the Coimbra Institute of Engineering (ISEC) and by the National Distributed Computing Infrastructure (INCD), funded by FCT and FEDER under the project 01/SAICT/2016 no. 022153.