structural insight into catalytic mechanism of pet hydrolase - polyethylene terephthalate properties
PET hydrolase (PETase)
Hydrolysis of polybenzene diester (PET)
It provides an attractive way for the biological transformation of plastic.
Here we introduce the structure of a new PETase from PET
In the complex with substrate and product analogs, the microbial Ideonella sakaiensis was consumed.
Through structural analysis, mutation and activity measurement, substrate-
A binding model was proposed and several key features of catalysis were clarified.
High molecular weight polymer composed of ester bonds-
With polyethylene glycol acetate (TPA)
And ethylene glycol (EG).
The durability and other good physical properties of PET make it one of the most widely used plastics.
However, the large number of pets entering and accumulating in the ecosystem poses a huge challenge to the environment. PET-
The hydrolysis enzyme that breaks PET into its building blocks can provide ecology
Friendly solutions for pet accumulation in the environment.
It has been previously reported that the hydrolases, including ASE, lipase and cutinase, exhibit PET-
Activities of degrading personality
Cutinase, which belongs to the chalase family, explores the catalytic mechanism of cutinase by analyzing the complex structure of inhibitors and natural substrate analogs (
Cutin and sorta).
However, PET in the chemical structure and accurate PET-
The binding method and mechanism of PET hydrolysis are not clear.
A new type of bacteria 201-
F6 was separated using PET as energy and carbon source.
In particular, it is attached to the surface of the pet and produces a unique cutinase-
Like an enzyme that degrade pets.
Through the hydrolysis of PET, the enzyme produces a single(2-hydroxyethyl)
Diacid to benzene (MHET), TPA and bis-2(hydroxyethyl)TPA (BHET)(Fig. ).
It is worth noting that the enzyme has several PET-
Activity of hydrolysis but showed lower activitynitrophenol-
Chain ester (
, Is the preferred substrate for lipases and cutinases.
Instead, it shows 5. 5-to 120-
Compared with other enzymes, the activity of PET was higher.
The enzyme is named as a PET enzyme (PETase)
Because of its pet preference.
PETase has shown excellent performance in the hydrolysis of PET and has great potential in further applications.
In this study, in order to determine the mechanism of enzyme-promoting PET hydrolysis, we identified natural PETase and two ligand-Binding complexes