Sandbox Reserved 1846: Difference between revisions
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== Function == | == Function == | ||
LCC catalyzes the hydrolysis of the ester bonds in PET polymers and breaks them down into their constituent monomers: terephthalic acid and ethylene glycol. The enzyme operates through a catalytic triad that consists of S165, D210, and H242. Using these residues, LCC can perform nucleophilic attacks on the carbonyl carbon atoms of the ester bonds in PET. During catalysis, the substrate binds in an elongated, predominantly hydrophobic groove present in the enzyme's structure. | LCC catalyzes the hydrolysis of the ester bonds in PET polymers and breaks them down into their constituent monomers: terephthalic acid and ethylene glycol. The enzyme operates through a catalytic triad that consists of S165, D210, and H242. Using these residues, LCC can perform nucleophilic attacks on the carbonyl carbon atoms of the ester bonds in PET. During catalysis, the substrate binds in an elongated, predominantly hydrophobic groove present in the enzyme's structure. | ||
LCC functions optimally at elevated temperatures (around 65-72°C), which approaches the [https://en.wikipedia.org/wiki/Glass_transition glass transition] temperature of PET. This temperature range maximizes PET chain mobility and makes the polymer more accessible to enzymatic action. The enzyme is remarkably thermostable compared to other PET hydrolases, with a melting temperature of 84.7°C. This property allows it to remain functional under these high-temperature conditions. Also unlike other PET hydrolases such as Is-PETase, BTA1, BTA2, and FsC, LCC | LCC functions optimally at elevated temperatures (around 65-72°C), which approaches the [https://en.wikipedia.org/wiki/Glass_transition glass transition] temperature of PET. This temperature range maximizes PET chain mobility and makes the polymer more accessible to enzymatic action. The enzyme is remarkably thermostable compared to other PET hydrolases, with a melting temperature of 84.7°C. This property allows it to remain functional under these high-temperature conditions. Also unlike other PET hydrolases such as Is-PETase, BTA1, BTA2, and FsC, LCC has substantially higher catalytic efficiency. Specifically, LCC has an initial PET-specific depolymerization rate of 93.2 mg TAeq. h⁻¹ mg⁻¹ enzyme at 65°C with amorphous PET. This means that it us at least 33 times more efficient than other tested enzymes.<ref name="Tournier">PMID:32269349</ref> | ||
LCC's function is limited by PET [https://en.wikipedia.org/wiki/Crystallization_of_polymers crystallinity], as the enzyme can more effectively hydrolyze amorphous regions of the polymer. As PET crystallinity increases during the depolymerization reaction (due to exposure to elevated temperatures), the enzyme's efficiency decreases. This limits complete depolymerization unless optimal conditions and enzyme variants are used. | LCC's function is limited by PET [https://en.wikipedia.org/wiki/Crystallization_of_polymers crystallinity], as the enzyme can more effectively hydrolyze amorphous regions of the polymer. As PET crystallinity increases during the depolymerization reaction (due to exposure to elevated temperatures), the enzyme's efficiency decreases. This limits complete depolymerization unless optimal conditions and enzyme variants are used. | ||