A PCL-degrading strain was isolated and identified as Pseudomonas sp. JQ-H3 through morphology observation and phylogenetic analysis. The strain showed the heterotrophic nitrification-aerobic denitrification (HN-AD) ability using PCL as a sole carbon source. About 93.11% of initial ammonium (102.41mg/L) was degraded within 36h with the maximum ammonium removal rate of 5.77mg/(L·h), while approximately 93.93% of initial nitrate (99.01mg/L) was removed within 48h with the maximum ammonium removal rate of 4.12mg/(L·h). 94.03% of PCL film with initial weight of 100mg was decomposed after 60days, and the extracellular lipases activity reached the maximum value of 9.18mU/mL at 30th days. In addition, the expression levels of amoA and nirS genes were promoted in the weak alkaline environment. The successful expression of napA, cnorB and nosZ genes further proved the HN-AD ability of the strain JQ-H3.
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