Biodegradation of Phenoxyacetic Acid in Soil by 'Pseudomonas putida'PP0301(pR0103), a Constitutive Degrader of 2,4-Dichlorophenoxyacetate

摘要

The efficacy of using genetically engineered microbes (GEMs) to degraderecalcitrant environmental toxicants was demonstrated by the application of Pseudomonas putida PP0301(pR0103) to an Oregon agricultural soil amended with 500 microg/g of a model xenobiotic, phenoxyacetic acid (PAA). P. putida PP0301(pR0103) is a constitutive degrader of 2,4-dichlorophenoxyacetate (2,4-D) and is also active on the non-inducing substrate, PAA. In unamended soil, survival of the plasmid-free parental strain P. putida PP0301 was similar to the survival of the GEM strain P. putida PP0301(pR103). However, in PAA amended soil, survival of the parent strain was over 10,000-fold lower (<3 colony forming units per gram of soil) than survival of the GEM strain after 39 days.