MHETase

[1] This pair of enzymes, PETase and MHETase, enable the bacterium Ideonella sakaiensis to live on the plastic PET as sole carbon source.

MHETase hydrolyses the ester bond of MHET forming terephthalic acid and ethylene glycol.

Ferulate and gallate esters, substrates of the closest relatives in the tannase family, are not converted.

MHEI is a likely industrial PET degradation product due to the use of isophthalate comonomer.

According to the classification in the ESTHER database, MHETase belongs to the family of tannases within block X.

Enzymatic PET degradation by PETase and MHETase
MHETA bound to MHETase. Short distances between the non-hydrolyzable ligand MHETA (mono hydroxyethyl terephthalamide in green) and the catalytic residues Ser225, His528 and Asp492 (part of the hydrolase domain in brown) or ligand binding residues (part of the lid domain in blue) are shown as dashed lines. PDB: 6QGC