{
    "title": "Ideonella sakaiensis vs Polyester",
    "inventor_name": "Shosuke Yoshida et al.",
    "publication_year": 2016,
    "device_name": "Ideonella sakaiensis (bacterium)",
    "goal": "Biodegradation of PET plastic to mitigate environmental pollution and enable recycling.",
    "problem_addressed": "Accumulation of polyethylene terephthalate (PET) plastic waste in the environment and limited recycling rates.",
    "concept_summary": "The bacterium Ideonella sakaiensis uses two enzymes, PETase and MHETase, to hydrolyze PET into its monomers-terephthalic acid and ethylene glycol-which can then be assimilated for growth. This enzymatic pathway offers a biological route to PET depolymerisation and potential recycling.",
    "detailed_description": null,
    "principles": [
        "Enzymatic hydrolysis",
        "Microbial metabolism",
        "Biocatalysis"
    ],
    "scientific_domains": [
        "Microbiology",
        "Biochemistry",
        "Polymer Chemistry",
        "Environmental Science"
    ],
    "mechanisms_of_action": [
        "PETase catalyzes the hydrolysis of PET polymer chains into mono(2-hydroxyethyl) terephthalic acid (MHET).",
        "MHETase further hydrolyzes MHET into terephthalic acid and ethylene glycol.",
        "The bacterium assimilates the resulting monomers as carbon and energy sources."
    ],
    "materials": [
        "Polyethylene terephthalate (PET) plastic",
        "PETase enzyme",
        "MHETase enzyme"
    ],
    "energy_sources": [
        "PET (used as carbon/energy source by the bacterium)"
    ],
    "inputs": [
        "PET waste (film or low-quality plastic)",
        "Water",
        "Nutrients (growth medium)"
    ],
    "outputs": [
        "Terephthalic acid",
        "Ethylene glycol",
        "Carbon dioxide",
        "Water"
    ],
    "claimed_performance": "Low-quality PET film was almost completely degraded within six weeks under laboratory conditions.",
    "experimental_evidence": "Laboratory tests reported in Science (Vol. 351, 2016) showed Ideonella sakaiensis degrading PET films, with enzymatic assays confirming PETase and MHETase activity.",
    "replication_status": "Results reported in a peer-reviewed study; no independent large-scale replication documented.",
    "keywords": [
        "PET",
        "Ideonella sakaiensis",
        "PETase",
        "MHETase",
        "Biodegradation",
        "Plastic recycling",
        "Enzymatic hydrolysis"
    ],
    "related_technologies": [
        "Enzymatic PET recycling",
        "Bioremediation of plastic waste",
        "Genetic engineering of PET-hydrolases"
    ],
    "controversy_level": "low",
    "confidence_score": 0.9,
    "practicability_score": 0.6,
    "fringe_score": 0.2,
    "evidence_strength": 0.7,
    "risk_score": 0.1,
    "trl_estimate": 3,
    "source_urls": [
        "https://www.theguardian.com/environment/2016/mar/10/could-a-new-plastic-eating-bacteria-help-combat-this-pollution-scourge",
        "http://science.sciencemag.org/content/351/6278/1196",
        "https://www.ncbi.nlm.nih.gov/pubmed/26291558",
        "https://en.wikipedia.org/wiki/Ideonella_sakaiensis",
        "https://en.wikipedia.org/wiki/PETase"
    ],
    "organizations": [
        "Kyoto Institute of Technology",
        "Keio University",
        "National Renewable Energy Laboratory",
        "University of Portsmouth"
    ],
    "applications": [
        "Industrial PET recycling",
        "Environmental remediation of PET pollution",
        "Biocatalytic production of terephthalic acid and ethylene glycol"
    ],
    "limitations": [
        "Slow degradation of highly crystalline PET (e.g., bottle-grade material).",
        "Current enzyme activity insufficient for commercial throughput.",
        "Need for optimisation of bacterial growth conditions and enzyme stability."
    ],
    "open_questions": [
        "Can engineered PETase variants achieve industrially relevant rates?",
        "What are the economic trade-offs compared with chemical depolymerisation?",
        "How to handle additives and contaminants released during biodegradation?"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "\"The bacteria almost completely degraded low-quality plastic within six weeks.\"",
        "\"PETase and MHETase are required to enzymatically convert PET efficiently into its two environmentally benign monomers.\"",
        "\"Our research results are just the initiation for the application. We have to work on so many issues needed for various applications.\"",
        "\"The use of these microbes or enzymes could play a role in remediation of plastic in a controlled reactor.\"",
        "\"PET is 100% recyclable, I expect that a biodegradation system would require a similar engineering process to chemical depolymerisation and as such is unlikely to be economically viable.\""
    ],
    "category": "Chemistry & Chemical Processes"
}