Journal article
Maintenance Role of a Glutathionyl-Hydroquinone Lyase (PcpF) in Pentachlorophenol Degradation by Sphingobium chlorophenolicum ATCC 39723
Journal of bacteriology, Vol.190(23), pp.7595-7600
12/2008
Handle:
https://hdl.handle.net/2376/114434
PMCID: PMC2583618
PMID: 18820023
Abstract
Pentachlorophenol (PCP) is a toxic pollutant. Its biodegradation has been extensively studied in Sphingobium chlorophenolicum ATCC 39723. All enzymes required to convert PCP to a common metabolic intermediate before entering the tricarboxylic acid cycle have been characterized. One of the enzymes is tetrachloro- p -hydroquinone (TeCH) reductive dehalogenase (PcpC), which is a glutathione (GSH) S -transferase (GST). PcpC catalyzes the GSH-dependent conversion of TeCH to trichloro- p -hydroquinone (TriCH) and then to dichloro- p -hydroquinone (DiCH) in the PCP degradation pathway. PcpC is susceptible to oxidative damage, and the damaged PcpC produces glutathionyl (GS) conjugates, GS-TriCH and GS-DiCH, which cannot be further metabolized by PcpC. The fate and effect of GS-hydroquinone conjugates were unknown. A putative GST gene ( pcpF ) is located next to pcpC on the bacterial chromosome. The pcpF gene was cloned, and the recombinant PcpF was purified. The purified PcpF was able to convert GS-TriCH and GS-DiCH conjugates to TriCH and DiCH, respectively. The GS-hydroquinone lyase reactions catalyzed by PcpF are rather unusual for a GST. The disruption of pcpF in S. chlorophenolicum made the mutant lose the GS-hydroquinone lyase activities in the cell extracts. The mutant became more sensitive to PCP toxicity and had a significantly decreased PCP degradation rate, likely due to the accumulation of the GS-hydroquinone conjugates inside the cell. Thus, PcpF played a maintenance role in PCP degradation and converted the GS-hydroquinone conjugates back to the intermediates of the PCP degradation pathway.
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Details
- Title
- Maintenance Role of a Glutathionyl-Hydroquinone Lyase (PcpF) in Pentachlorophenol Degradation by Sphingobium chlorophenolicum ATCC 39723
- Creators
- Yan Huang - Washington State UniversityRandy Xun - School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4234Guanjun Chen - Shandong UniversityLuying Xun - School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4234
- Publication Details
- Journal of bacteriology, Vol.190(23), pp.7595-7600
- Academic Unit
- School of Molecular Biosciences
- Publisher
- American Society for Microbiology (ASM)
- Number of pages
- 6
- Identifiers
- 99900547841101842
- Language
- English
- Resource Type
- Journal article