Degradation of PET plastic with engineered environmental bacteria is an exciting and important
innovation bacteria like Escherichia coli or Bacillus subtilis are genetically modified to produce PETase
(and sometimes MHETase), enzymes that break down PET into terephthalic acid and ethylene glycol.
These compounds can then be fully mineralized or upcycled into valuable chemicals, offering a
circular-economy approach (Brown et al., 2023).
In Tanzania, although no large-scale engineered PET-degrading bacteria have been deployed,
researchers have isolated native microbes (bacteria, fungi, actinomycetes) from Morogoro soils that
degrade polyethylene plastics in lab tests—clear zones up to 66 mm in diameter after two weeks (Nakei
et al., 2022). It suggests our soils already host organisms with bioremediation potential. However, PET (a
polyester) differs chemically from polyethylene; so far, Tanzanian isolates have not yet been tested on
PET specifically. Still, local adaptation of engineered consortia could be promising to the developing
countries like Tanzania
The environmental impact in our region could be positive such as the following expapined: fewer PET
bottles littering streets, waterways and farmland; slower microplastic contamination; reduced CO₂
emissions compared to incineration. But risks include release of genetically modified organisms into soil
or water systems: potential disruption of native microbial communities or gene transfer to non-target
species; careful containment and monitoring would be essential.
Next steps toward making this method common practice in Tanzania: first, pilot-scale studies in
controlled wastewater or compost facilities, using engineered consortia of B. subtilis secreting PETase
and MHETase alongside indigenous degraders (Ronda et al., 2019). Second, public-private partnerships
to integrate enzymatic PET recycling in local recycling centers. Finally, clear regulatory frameworks and
environmental risk assessments are needed before field release!
References
Nakei, M. D., Misinzo, G., Tindwa, H., & Semu, E. (2022). Degradation of polyethylene plastic bags and
bottles using microorganisms isolated from soils of Morogoro, Tanzania. Frontiers in Microbiology, 13,
1077588. https://doi.org/10.3389/fmicb.2022.1077588
innovation bacteria like Escherichia coli or Bacillus subtilis are genetically modified to produce PETase
(and sometimes MHETase), enzymes that break down PET into terephthalic acid and ethylene glycol.
These compounds can then be fully mineralized or upcycled into valuable chemicals, offering a
circular-economy approach (Brown et al., 2023).
In Tanzania, although no large-scale engineered PET-degrading bacteria have been deployed,
researchers have isolated native microbes (bacteria, fungi, actinomycetes) from Morogoro soils that
degrade polyethylene plastics in lab tests—clear zones up to 66 mm in diameter after two weeks (Nakei
et al., 2022). It suggests our soils already host organisms with bioremediation potential. However, PET (a
polyester) differs chemically from polyethylene; so far, Tanzanian isolates have not yet been tested on
PET specifically. Still, local adaptation of engineered consortia could be promising to the developing
countries like Tanzania
The environmental impact in our region could be positive such as the following expapined: fewer PET
bottles littering streets, waterways and farmland; slower microplastic contamination; reduced CO₂
emissions compared to incineration. But risks include release of genetically modified organisms into soil
or water systems: potential disruption of native microbial communities or gene transfer to non-target
species; careful containment and monitoring would be essential.
Next steps toward making this method common practice in Tanzania: first, pilot-scale studies in
controlled wastewater or compost facilities, using engineered consortia of B. subtilis secreting PETase
and MHETase alongside indigenous degraders (Ronda et al., 2019). Second, public-private partnerships
to integrate enzymatic PET recycling in local recycling centers. Finally, clear regulatory frameworks and
environmental risk assessments are needed before field release!
References
Nakei, M. D., Misinzo, G., Tindwa, H., & Semu, E. (2022). Degradation of polyethylene plastic bags and
bottles using microorganisms isolated from soils of Morogoro, Tanzania. Frontiers in Microbiology, 13,
1077588. https://doi.org/10.3389/fmicb.2022.1077588
