PRESENCE, PROLIFERATION AND DISTRIBUTION OF BACTERIAL METALDEHYDE-DEGRADING GENES IN SOILS FROM NORTHERN ENGLAND

The first cluster of metaldehyde-degrading genes has been recently described. A sensitive probe-based qPCR assay for degrading gene cluster detection was developed and the technique was successfully used in different soils. Higher number of gene copies correlated with periods of metaldehyde removal for half of the soils. The gene cluster was not detected in the other half of the soils indicating that other biological degrading pathways are also important. It was confirmed that the metaldehyde-degrading population proliferates in response to the pesticide.Third generation sequencing was used to obtain a reference genome for the model degrader Acinetobacter calcoaceticus E1. IS91 and IS6-family insertion sequences were found surrounding the degrading gene cluster. They were hypothesised to be responsible for degrading gene dissemination to different taxa. A plasmid denominated pAME76 was found to harbour the degrading operon and bioinformatic analyses suggested that the genes are also located in plasmids in most of the other isolates.