Acesulfame-degrading bacteria isolated from wastewater treatment plants in Germany. undefined

The artificial sweetener acesulfame is a widespread micropollutant in rivers, lakes and even tap water due to its persistency and mobility in aquatic environments. It has long been considered recalcitrant to microbial attack, but recent studies indicated the emerging potential of acesulfame removal in biological wastewater treatment and suggested a catabolic process leading to complete mineralization. Here, we analyzed the genomes of eight acesulfame-degrading strains affiliated to the genera Bosea and Chelatococcus, which were isolated from municipal wastewater treatment plants in Germany after aerobic enrichment on acesulfame as sole carbon source. Additionally, we sequenced the genome of a degradation-defective mutant of one acesulfame-degrading Bosea strain, which had been obtained by multiple transfers in non-selective medium. Comparative genomics revealed first indications of the genetic background of the acesulfame degradation trait and its worldwide distribution by horizontal gene transfer.