4LBI

5-chloro-2-hydroxyhydroquinone dehydrochlorinase (TftG) from Burkholderia phenoliruptrix AC1100: Selenomethionyl Apo-form

Summary for 4LBI

• Entry DOI: 10.2210/pdb4lbi/pdb
• Related: 4LBH 4LBP
• Descriptor: 5-chloro-2-hydroxyhydroquinone dehydrochlorinase (TftG) (2 entities in total)
• Functional Keywords: lyase
• Biological source: Burkholderia cepacia
• Total number of polymer chains: 4
• Total formula weight: 45289.40

Authors

Hayes, R.P.,Lewis, K.M.,Xun, L.,Kang, C. (deposition date: 2013-06-20, release date: 2013-08-28, Last modification date: 2013-10-23)

Primary citation

Hayes, R.P.,Lewis, K.M.,Xun, L.,Kang, C.
Catalytic Mechanism of 5-Chlorohydroxyhydroquinone Dehydrochlorinase from the YCII Superfamily of Largely Unknown Function.
J.Biol.Chem., 288:28447-28456, 2013

PubMed Abstract: 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.

PubMed: 23955343
DOI: 10.1074/jbc.M113.499368

Experimental method

X-RAY DIFFRACTION (2.21 Å)