Schenzle, Andreas.Andreas.SchenzleLenke, H.H.LenkeSpain, J.C.J.C.SpainKnackmuss, H.-J.H.-J.Knackmuss2022-03-032022-03-031999https://publica.fraunhofer.de/handle/publica/1944852-s2.0-0033012574Ralstonia eutropha JMP134 utilizes 2-chloro-5-nitrophenol as a sole source of nitrogen, carbon, and energy. The initial steps for degradation of 2-chloro-5-nitrophenol are analogous to those of 3-nitrophenol degradation in R. eutropha JMP134. 2-Chloro-5-nitrophenol is initially reduced to 2-chloro-5-hydroxylaminophenol, which is subject to an enzymatic Bamberger rearrangement yielding 2-amino-5-chlorohydroquinone. The chlorine of 2-amino-5-chlorohydroquinone is removed by a reductive mechanism, and aminohydroquinone is formed. 2-Chloro-5-nitrophenol and 3-nitrophenol induce the expression of 3-nitrophenol nitroreductase, of 3-hydroxylaminophenol mutase, and of the dechlorinating activity. 3-Nitrophenol nitroreductase catalyzes chemoselective reduction of aromatic nitro groups to hydroxylamino groups in the presence of NADPH. 3-Nitrophenol nitroreductase is active with a variety of mono-, di-, and trinitroaromatic compounds, demonstrating a relaxed substrate specificity of the enzyme. N itrosobenzene serves as a substrate for the enzyme and is converted faster than nitrobenzene.en2-chloro-5-nitrophenol degradationbiodegradationnitro group reductionRalstonia eutropha JMP134reductive dechlorination610620660579journal article