Engineered yeast for the efficient hydrolysis of polylactic acid

Area of Science:

• Biotechnology
• Environmental Science
• Polymer Science

Background:

• Polylactic acid (PLA) is a widely used bioplastic, but its persistence in the environment poses waste management challenges.
• Current organic waste treatment methods are insufficient for complete PLA degradation, leading to environmental accumulation.
• Efficient enzymatic hydrolysis of PLA is crucial for developing sustainable and eco-friendly waste management strategies.

Purpose of the Study:

• To develop an effective and cost-efficient method for producing a polylactic acid (PLA)-degrading enzyme.
• To evaluate the potential of a recombinant fungal cutinase-like enzyme (CLE1) expressed in yeast for PLA hydrolysis.
• To optimize enzyme production and hydrolysis efficiency for practical PLA recycling applications.

Main Methods:

• Recombinant expression of a codon-optimized fungal cutinase-like enzyme (CLE1) in Saccharomyces cerevisiae.
• Utilized a crude supernatant from the engineered yeast strain for enzymatic hydrolysis experiments.
• Quantified lactic acid production and measured weight loss of PLA films to assess hydrolysis efficiency.

Main Results:

• The Y294[CLEns] yeast strain demonstrated superior enzyme production and PLA hydrolysis capabilities.
• The enzyme successfully degraded various polylactic acid materials, releasing up to 9.44 g/L lactic acid from 10 g/L PLA films.
• Achieved over 40% weight loss in PLA films, indicating significant hydrolytic activity.

Conclusions:

• Fungal hosts, such as yeast, can be effectively engineered for the production of potent PLA hydrolases.
• The developed enzymatic system shows significant promise for commercial applications in polylactic acid recycling.
• This research contributes to cleaner, more energy-efficient, and environmentally friendly bioplastic waste management solutions.