Characterization of the propanil biodegradation pathway in Sphingomonas sp. Y57 and cloning of the propanil hydrolase gene prpH

► Sphingomonas sp. Y57 was able to degrade both propanil and 3,4-DCA. ► N-acylation and N-deacylation occurred in the 3,4-DCA degradation process. ► N-propionylation of 3,4-DCA was found for the first time. ► Sphingomonas sp. Y57 was able to convert 3,4-DCA to 4,5-dichlorocatechol. ► The first bacterial propanil hydrolase gene prpH was cloned from Y57.