Polyester hydrolysis is enhanced by a truncated esterase: Less is more

An esterase from Clostridium botulinum (Cbotu_EstA) previously reported to hydrolyze the biodegradable polyester poly(butylene adipate-co-terephthalate) was redesigned to improve the hydrolysis of synthetic polyesters. Increased activity was indeed observed for del71Cbotu_EstA variant, which performed activity on the widespread polyester polyethylene terephthalate, which was not able to be attacked by the wild-type enzyme Cbotu_EstA. Analysis of the 3D structure of the enzyme showed that removing 71 residues at the N-terminus of the enzyme exposed a hydrophobic patch on the surface and improved sorption of hydrophobic polyesters concomitantly facilitating the access of the polymer to the active site. These results show a new route for enhancing enzyme activity for hydrolysis and modification of polyesters.