4LBH: 5-chloro-2-hydroxyhydroquinone Dehydrochlorinase (tftg) From Burkholderia Phenoliruptrix Ac1100: Apo-form

TftG, 5-chloro-2-hydroxyhydroquinone (5-CHQ) dehydrochlorinase, is involved in the biodegradation of 2,4,5-trichlorophenoxyacetate by Burkholderia phenoliruptrix AC1100. It belongs to the YCII superfamily, a group of proteins with largely unknown function. In this work, we utilized structural and functional studies, including the apo-form and 2,5-dihydroxybenzoquinone binary complex crystal structures, computational analysis, and site-directed mutagenesis, to determine the dehydrochlorination mechanism. The His-Asp dyad, which initiates catalysis, is strongly conserved in YCII-like proteins. In addition, other catalytically important residues such as Pro-76, which orients the His-Asp catalytic dyad; Arg-17 and Ser-56, which form an oxyanion hole; and Asp-9, which stabilizes the oxyanion hole, are among the most highly conserved residues across the YCII superfamily members. The comprehensive characterization of TftG helps not only for identifying effective mechanisms for chloroaromatic dechlorination but also for understanding the functions of YCII superfamily members, which we propose to be lyases.
PDB ID: 4LBHDownload
MMDB ID: 113057
PDB Deposition Date: 2013/6/20
Updated in MMDB: 2013/10
Experimental Method:
x-ray diffraction
Resolution: 1.75  Å
Source Organism:
Similar Structures:
Biological Unit for 4LBH: tetrameric; determined by author and by software (PISA)
Molecular Components in 4LBH
Label Count Molecule
Proteins (4 molecules)
5-chloro-2-hydroxyhydroquinone Dehydrochlorinase (Tftg)
Molecule annotation
Chemicals (4 molecules)
* Click molecule labels to explore molecular sequence information.

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