A strategy for in situ sustainable PET degradation in soil by genetically engineered bacteria constructed from...

The persistent nature of polyethylene terephthalate (PET) has led to increasingly severe environmental pollution of soils. In this study, we propose and evaluate a generalizable strategy that employs genetically engineered bacteria (GEB) derived from soil for in situ PET degradation in soil. We applied a broadly applicable delivery approach, which combines electroporation with a transposon system, to integrate the FAST-PETase gene into the genomes of six distinct soil-isolated bacterial strains, thereby constructing six GEBs with an efficient PET-degrading capability. These GEBs expressed and secreted PETase extracellularly, leading to detectable degradation of PET fragments under laboratory conditions. When introduced into the soil environment, they stably colonized the soil for at least four months, with the FAST-PETase gene remaining detectable and transcriptionally active, and induced corrosive effects on the PET fragments. Supplementation with these GEBs did not significantly alter the taxonomic composition or functional diversity of the native soil microbial community, suggesting minimal ecological disturbance and providing a novel pathway for carbon source utilization in soil. Overall, this study established the long-term survival and functional stability of GEBs in the soil environment, offering a potential strategy for the bioremediation of PET-contaminated soils, as well as a generalizable methodology for the in situ remediation of other environmental pollutants.