Abstract
Cutinases are promising agents for poly(ethylene terephthalate) (PET) bio-recycling because of their ability to produce the PET monomer terephthalic acid with high efficiency under mild reaction conditions. In this study, we found that the low-crystallinity PET (lcPET) hydrolysis activity of thermostable cutinase from Thermobifida fusca (TfCut2), was increased by the addition of cationic surfactant that attracts enzymes near the lcPET film surface via electrostatic interactions. This approach was applicable to the mutant TfCut2 G62A/F209A, which was designed based on a sequence comparison with PETase from Ideonella sakaiensis. As a result, the degradation rate of the mutant in the presence of cationic surfactant increased to 31 ± 0.1 nmol min−1 cm−2, 12.7 times higher than that of wild-type TfCut2 in the absence of surfactant. The long-duration reaction showed that lcPET film (200 μm) was 97 ± 1.8% within 30 h, the fastest biodegradation rate of lcPET film thus far. We therefore believe that our approach would expand the possibility of enzyme utilization in industrial PET biodegradation.
Highlights
Cutinases are promising agents for poly(ethylene terephthalate) (PET) bio-recycling because of their ability to produce the PET monomer terephthalic acid with high efficiency under mild reaction conditions
We found that the low-crystallinity PET hydrolysis activity of thermostable cutinase from Thermobifida fusca (TfCut2), was increased by the addition of cationic surfactant that attracts enzymes near the lcPET film surface via electrostatic interactions
We previously showed that the hydrolysis reaction was inhibited if the reaction was performed with surfactants carrying the same charge as the enzyme surface[21], C12-OSO3− improved TfCut[2] activity 4.3-fold, perhaps because the cationic regions at the protein surface interact with the anionic surfactant
Summary
Cutinases are promising agents for poly(ethylene terephthalate) (PET) bio-recycling because of their ability to produce the PET monomer terephthalic acid with high efficiency under mild reaction conditions. We found that the low-crystallinity PET (lcPET) hydrolysis activity of thermostable cutinase from Thermobifida fusca (TfCut2), was increased by the addition of cationic surfactant that attracts enzymes near the lcPET film surface via electrostatic interactions. This approach was applicable to the mutant TfCut[2] G62A/F209A, which was designed based on a sequence comparison with PETase from Ideonella sakaiensis. A mutant TfCut[2] was designed to further improve catalytic activity (Fig. 1e)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have