AUTHOR=Liu Yu , Liu Chen , Liu Huan , Zeng Qi , Tian Xinpeng , Long Lijuan , Yang Jian 

TITLE=Catalytic Features and Thermal Adaptation Mechanisms of a Deep Sea Bacterial Cutinase-Type Poly(Ethylene Terephthalate) Hydrolase

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2022.865787

DOI=10.3389/fbioe.2022.865787

ISSN=2296-4185

ABSTRACT=<p>Poly (ethylene terephthalate) (PET) plastic is chemically inert and persistent. Massive quantities of PET waste end up in landfill sites and oceans, posing major global pollution concerns. PET degrading enzymes with high efficiency provide plastic recycling and bioremediation possibilities. Here, we report a novel cutinase, <italic>Mt</italic>Cut with distinct catalytic behaviors, derived from the deep sea <italic>Nocardiopsaceae</italic> family strain. Biochemical analyses showed <italic>Mt</italic>Cut efficiently hydrolyzed PET at ambient temperatures and in an exo-type manner. The activity and stability of <italic>Mt</italic>Cut were enhanced by the addition of calcium ions. Notably, no hydrolysis products inhibition was observed during PET depolymerization, suggesting <italic>Mt</italic>Cut is a better biocatalyst when compared to other PET hydrolases. In addition, structural components associated with thermal adaptation were investigated using molecular dynamic (MD) simulations, and key regions regulating <italic>Mt</italic>Cut thermostability were identified. Our biochemical and structural analyses of <italic>Mt</italic>Cut deepen the understanding of PET hydrolysis by cutinases, and provide invaluable insights on improvement and performance engineering strategies for PET-degrading biocatalysts.</p>