Open AccessPurification and characterization of 2,4‐dichlorophenol hydroxylase isolated from a bacterium of the α‐2 subgroup of the Proteobacteria
Author(s) -
Makdessi Kathrin,
Lechner Ute
Publication year - 1997
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1997.tb12758.x
Subject(s) - 2,4 dichlorophenol , enzyme , biochemistry , proteobacteria , bacteria , biology , peptide sequence , stereochemistry , chemistry , gene , 16s ribosomal rna , genetics
2,4‐Dichlorophenol hydroxylase (EC 1.14.13.20) was purified to apparent homogeneity from the bacterial strain S1, a member of the α‐2 subgroup of the Proteobacteria . The molecular masses of the native enzyme and the subunit were determined to be 256 and 64 kDa, respectively, suggesting a homotetrameric structure. The enzyme converted 2,4‐dichlorophenol to 3,5‐dichlorocatechol. The apparent K m values for 2,4‐dichlorophenol, NADPH and NADH were 3, 240 and 420 μM, respectively. The enzyme hydroxylated a broad range of halogenated phenols. 3‐Chloro‐, 2,6‐dichloro‐ and 2,4,6‐trichlorophenol acted as ‘non‐substrate' effectors. The N‐terminal sequence revealed 72% identity with the amino acid sequence deduced from the pJP4‐encoded tfdB gene.