Open AccessAnalysis of the C‐terminal domain of Burkholderia sp. strain LB400 BphK reveals a conserved motif that affects catalytic activity
Author(s) -
Gilmartin Niamh,
Ryan David,
Dowling David N.
Publication year - 2005
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 - 10.1016/j.femsle.2005.05.056
Subject(s) - operon , transferase , biochemistry , conserved sequence , biology , enzyme , glutathione s transferase , mutagenesis , gene , catalytic triad , genetics , chemistry , glutathione , peptide sequence , mutation , mutant
The bphK gene encoding glutathione S‐transferase (GST) is located in the bph operon (PCB co‐metabolism) in Burkholderia sp. strain LB400 and the enzyme has recently been shown to have dechlorination activity in relation to 4‐chlorobenzoate (4‐CBA). Alignments using other glutathione S‐transferase sequences found in PCB degradation operons identified a highly conserved region in the C‐terminal domain of these enzymes that included a conserved motif implicated in protein folding in eukaryotic GSTs. Site‐directed mutagenesis indicated that the region is indirectly involved in the catalytic activity and substrate specificity of BphK. Predicted hydrogen bond interactions involving Asp155 play an important role in the enzymatic properties of this glutathione S‐transferase.