  Accumulation of plastic waste is a major environmental problem. Enzymes,
particularly esterases, play an important role in the biodegradation of
polyesters. These enzymes are usually only active on aliphatic polyesters, but
a few have showed catalytic activity for semi-aromatic polyesters. Due to the
importance of these processes, an atomic level characterization of how common
polyesters are degraded by esterases is necessary. Hereby, we present a
Molecular dynamics (MD) and Quantum Mechanics/Molecular Mechanics (QM/MM) MD
study of the hydrolysis of a model of polycaprolactone (PCL), one of the most
widely used biomaterials, by the thermophilic esterase from the archaeon
Archaeoglobus fulgidus (AfEST). This enzyme is particularly interesting because
it can withstand temperatures well above the glass transition of many
polyesters. Our insights about the reaction mechanism are important for the
design of customized enzymes able to degrade different synthetic polyesters.
