Screening and genome analysis of a Pseudomonas stutzeri that degrades PET monomer terephthalate

Abstract:

[Objective] To screen and identify microorganisms capable of metabolizing polyethylene terephthalate monomer terephthalate and analyze the catabolic pathways.[Methods] Collected samples from Qingdao Xiaojianxi solid waste comprehensive disposal plant and screened strains capable of metabolizing terephthalate using the medium with terephthalate as the sole carbon source; 16S rRNA phylogenetic tree analysis was used to determine the taxonomic status of TPA3 strain; de novo sequencing was implemented using the second-generation and the third-generation high-throughput sequencing technologies; the terephthalate and ethylene glycol catabolic pathways and the related genes of TPA3 were analyzed through amino acid sequence alignment; the genetic manipulability of TPA3 was verified by the reported genetic manipulative techniques.[Results] TPA3 was identified as Pseudomonas stutzeri; it can metabolize 10.60 g/L terephthalate within 30 hours at 30℃. After culture and domestication, it could also catabolize ethylene glycol. The complete genome was composed of one chromosome and three plasmids for a total genome size of 4.55 Mb. It was speculated that TPA3 strain catabolized terephthalate in a classic way, and the ethylene glycol catabolic pathway should be similar to Pseudomonas putida KT2440. The genetic manipulation technology of Pseudomonas could be used for TPA3.[Conclusion] TPA3 strain could degrade polyethylene terephthalate monomers terephthalate and ethylene glycol, and could be genetically modified, showing potential application value in polyethylene terephthalate waste biological treatment technology.

Key words:plastic pollution;polyethylene terephthalate;de novo sequencing;metabolic pathway;genetic manipulation technique