We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
The Action of Plastic Degrading Enzyme is Accelerated Mainly Due to an Increase in Thermal Stability Rather Than by Inherent Catalytic Effect
AI summary Read the abstract
Researchers used computational simulations to investigate why the engineered FAST-PETase enzyme breaks down PET plastic more efficiently than its wild-type counterpart, finding that enhanced thermal stability — rather than direct catalytic improvements — is the primary driver of its superior performance at elevated temperatures.
Polyethylene terephthalate (PET) hydrolases offer a promising enzymatic route to plastic waste degradation under mild conditions. Among these, the engineered FAST-PETase variant exhibits superior catalytic efficiency and thermostability compared to the wild-type IsPETase, yet the molecular origins of these enhancements remain debated. In this work, we employ empirical valence bond (EVB) simulations in conjunction with semi-macroscopic PDLD/S-LRA calculations to investigate the rate-determining acylation step in PET dimer hydrolysis catalyzed by both wild-type and FAST-PETase. Our results successfully reproduce the experimentally observed trend in catalytic rate enhancement between the two systems. While prior interpretations attributing the improved activity to a strengthened hydrogen-bond network involving Asp106 and His237, we demonstrate that the distal N233K mutation in FAST-PETase induces long-range electrostatic changes that enhance catalytic efficiency by modulating the active site dipolar environment. More importantly, we show that the elevated performance of FAST-PETase at higher temperatures is not due to reduced flexibility in the mutant region but arises from enhanced thermal stability, which allows the enzyme to operate effectively at elevated temperatures and thus accelerate reaction rates. These findings underscore the central role of electrostatics and stability in enzyme engineering and suggest that data-driven methods, such as maximum entropy models, may enable the rational identification of further stability-enhancing mutations for improved PET depolymerization.
More Papers Like This
Insights into the Enhancement of the Poly(ethylene terephthalate) Degradation by FAST-PETase from Computational Modeling
AI summary Read the abstract
"Researchers used classical and quantum mechanical/molecular mechanics simulations to reveal why the engineered enzyme FAST-PETase degrades PET plastic far more efficiently than its parent enzyme PETase, tracing the enhancement to a single N233K mutation that increases the basicity of a catalytic residue and lowers the energy barrier for the rate-limiting acylation step by over 4 kcal/mol. These findings provide molecular-level design principles for engineering even more effective plastic-degrading enzymes."
Molecular dynamics simulations of temperature-dependent PET binding in PETase, ThermoPETase, and FAST-PETase
AI summary Read the abstract
Molecular dynamics simulations comparing wild-type IsPETase with two engineered variants (ThermoPETase and FAST-PETase) showed that FAST-PETase exhibited the highest thermal stability and preserved PET binding at elevated temperatures where the wild-type enzyme lost substrate contact. Engineering thermostable PET-degrading enzymes is a promising strategy for biological treatment of PET microplastic pollution at industrial scales.
On the Role of Temperature in the Depolymerization of PET by FAST‐PETase: An Atomistic Point of View on Possible Active Site Pre‐Organization and Substrate‐Destabilization Effects
AI summary Read the abstract
Researchers used molecular simulations to understand why the plastic-degrading enzyme FAST-PETase works better at 50°C than at lower temperatures when breaking down PET plastic. They found that at the optimal temperature the enzyme's active site pre-organizes itself to bind PET more efficiently, and the enzyme forces the plastic into a more reactive shape. Understanding these mechanisms can guide the engineering of even more effective enzymes for breaking down PET microplastics and plastic waste at practical scales.
Temperature-Dependent Reorganization of Conformational Dynamics and Interaction Networks Underlies Thermostability in PET-Degrading Enzymes
AI summary Read the abstract
Scientists are studying how to engineer sturdier enzymes that can break down plastic bottles (PET) into reusable materials, since natural plastic-eating enzymes tend to fall apart at the high temperatures needed for efficient recycling. By using computer simulations to compare a natural enzyme with two engineered, heat-resistant versions, researchers pinpointed exactly what structural features let the improved enzymes stay stable and functional under heat. This matters because better plastic-recycling enzymes could help reduce the massive amount of plastic waste that breaks down into microplastics — tiny particles increasingly found in our food
Dynamic shift of internal electric field accelerates enzymatic polyethylene terephthalate depolymerization
AI summary Read the abstract
Quantum mechanics/molecular mechanics simulations reveal that PET depolymerization by the hydrolase LCCICCG is controlled by a dynamically shifting internal electric field that stabilizes transition states, lowering the rate-determining energy barrier to 20.4 kcal/mol. These mechanistic insights into how enzyme internal electric fields drive plastic hydrolysis provide a rational engineering framework for designing more efficient PET-degrading enzymes, directly advancing enzymatic approaches to eliminating PET microplastic pollution.
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.