0
Article Tier 2 Environmental Sources Policy & Risk Remediation Sign in to save

An absorbance method for analysis of enzymatic degradation kinetics of poly(ethylene terephthalate) films

Scientific Reports 2021 118 citations

AI summary Read the abstract

Researchers developed a fast absorbance-based method to assess PET-degrading enzyme (PETase) kinetics and used it to characterize a thermostable engineered variant (denaturation temperature 69.4°C), finding 5–7 fold improved catalytic rates compared to the wild-type enzyme.

Increased interest in poly(ethylene terephthalate) (PET)-degrading enzymes (PETases) have generated efforts to find mutants with improved catalytic activity and thermostability. Here, we present a simple and fast method to determine relative enzyme kinetics through bulk absorbance measurements of released products over time. A thermostable variant of PETase from Ideonella sakaiensis was engineered (R280A S121E D186H N233C S282C) with a denaturation temperature of 69.4 ± 0.3 °C. This was used to assess the method's ability to determine relative enzyme kinetics across variants and reveal structure-function relationships. Measurements at 24 and 72 h at 400 nM of enzyme suggest that the mutations improved catalytic rates 5- to 7-fold. On the contrary, kinetic analyses of the thermostable variant and wild-type reveal different reaction trajectories despite similar maximum catalytic rates, resulting in higher product accumulation from the thermostable variant over time. The results of the assay support the necessity for kinetic measurements to determine relationships between sequence and function for IsPETase and other PET hydrolases.

More Papers Like This

Article Tier 2

Evaluation of enzymatic degradation of petase against PBT and PEN nanoplastics using dye release assay

AI summary Read the abstract

Researchers expressed, purified, and tested wild-type and engineered variants of PETase enzyme against polyethylene naphthalate and polybutylene terephthalate nanoplastic substrates, developing a dye-release fluorescence assay that correlated with HPLC measurements to enable rapid, quantitative screening of enzymatic plastic degradation.

Article Tier 2

Determinants for an Efficient Enzymatic Catalysis in Poly(Ethylene Terephthalate) Degradation

AI summary Read the abstract

This review covers the current state of enzymatic PET degradation, examining which enzymes act on PET, how protein engineering has improved their activity, and what challenges remain before enzymatic recycling can be deployed at industrial scale.

Article

A new continuous assay for quantitative assessment of enzymatic degradation of poly(ethylene terephthalate) (PET)

AI summary Read the abstract

Researchers developed a novel continuous UV absorbance assay for measuring enzymatic degradation of PET plastic in real time, enabling faster and more robust kinetic characterization of PET-hydrolyzing enzymes compared to traditional manual sampling methods.

Article Tier 2

An Overview into Polyethylene Terephthalate (PET) Hydrolases and Efforts in Tailoring Enzymes for Improved Plastic Degradation

AI summary Read the abstract

This review examines the discovery and engineering of PET-degrading enzymes including PETase and cutinase variants, discussing protein engineering strategies to improve catalytic efficiency and thermostability for practical biodegradation of polyethylene terephthalate plastic waste.

Article Tier 2

A versatile assay platform for enzymatic poly(ethylene-terephthalate) degradation

AI summary Read the abstract

Researchers developed a fast, reliable assay platform for testing enzymes that break down PET plastic, a common component of bottles and packaging. Better enzyme-based recycling tools could help reduce PET accumulation in the environment and the microplastics it generates.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper