title: The two enantiospecific dichlorprop/alpha-ketoglutarate-dioxygenases from Delftia acidovorans MC1--protein and sequence data of RdpA and SdpA.
abstract: Two alpha-ketoglutarate-dependent dioxygenases carrying enantiospecific activity for the etherolytic cleavage of racemic phenoxypropionate herbicides [(RS)-2-(2,4-dichlorophenoxy)propionate and (RS)-2-(4-chloro-2-methylphenoxy)propionate] from Delftia acidovorans MC1 were characterized with respect to protein and sequence data. The (S)-phenoxypropionate/alpha-ketoglutarate-dioxygenase (SdpA) appeared as a monomeric enzyme with a molecular weight of 32 kDa in the presence of SDS. N-terminal sequences revealed relationship to alpha-ketoglutarate-dependent taurine dioxygenase (TauD) and to 2,4-dichlorophenoxyacetate/alpha-ketoglutarate-dioxygenase (TfdA). The (R)-phenoxypropionate/alpha-ketoglutarate-dioxygenase (RdpA) referred to 36 kDa in the presence of SDS and to 108 kDa under native conditions. Internal sequences of fragments obtained after digestion made evident relationship to TfdA and TauD. Two-dimensional electrophoretic separation resulted in the resolution of up to 3 individual spots with almost identical molecular weights but different isoelectric points with both RdpA and SdpA. The structural differences of these isoenzyme forms are not yet clear.
authors.affiliation: UFZ Centre for Environmental Research, Department of Environmental Microbiology, Permoserstr. 15, D-04318 Leipzig, Germany. annewest@umb.ufz.de
authors.forename: Anne
authors.initials: A
authors.lastname: Westendorf
authors.forename: Dirk
authors.initials: D
authors.lastname: Benndorf
authors.forename: Roland H
authors.initials: RH
authors.lastname: Müller
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Babel
mesh_terms: D000595:Amino Acid Sequence; D006899:Mixed Function Oxygenases / Q000737:chemistry*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020560:Proteobacteria / Q000201:enzymology*; D013237:Stereoisomerism
chemical_list: D006899:Mixed Function Oxygenases; C084087:2,4-dichlorophenoxyacetate-alpha-ketoglutarate dioxygenase