Skip to main content
Home Whitman College Penrose Library | Arminda Collections

Main menu

  • Home
  • Browse Collections
  • About
  • Login
  1. Home
  2. Honors Theses
  3. Enzymes for applications in bioremedation : a site-directed mutagenesis study of second coordination sphere residues in PcpA
Title

Enzymes for applications in bioremedation : a site-directed mutagenesis study of second coordination sphere residues in PcpA

    Item Description
    Limited Access
    The author(s) chose to restrict access to this thesis to current Whitman students, faculty, and staff. Please log in to view it.
    Linked Agent
    Creator (cre): DaRosa, Paul A.
    Advisor (adv): Machonkin, Tim
    Department (dpt): Whitman College. Chemistry Department
    Date
    May 10, 2010
    Graduation Year
    2010
    Abstract

    Chlorinated xenobiotic compounds such as pentachlorophenol are destructive to the environment and are toxic to most organisms. The removal of these chemicals is difficult due to their intrinsic properties. The stability and limited biodegradability of chlorinated aromatic compounds make these chemicals particularly challenging targets for bioremediation. Degradation pathways of chlorinated arenes tend to be inefficient due to dead end metabolites and bottlenecks. To increase the rate of biodegradation and remove bottlenecks, creation of hybrid strains through patchwork assembly, pathway engineering, or protein engineering may be necessary. This can only be achieved if the enzymes in these pathways are well characterized. In this study, site-directed mutagenesis was performed on Sphingobium chlorophenolicum 2,6-dichlorohydroquinone 1,2-dioxygenase (PcpA). PcpA is a nonheme Fe(II)-containing enzyme that oxidatively cleaves 2,6-dichlorohydroquinone in the degradation pathway of pentachlorophenol and has potential applications in bioremediation. The second coordination sphere residues, H49 and R259, were mutated to various amino acids to study the role of these residues in the enzymes’ structure and catalysis. R259 is proposed to have an important structural role in pcpA, while H49 is proposed to have an acid/base role in the oxidative ring cleavage of 2,6-dichlorohydroquinone by PcpA. The information obtained from these mutations offers a starting point for further studies of substrate specificity and the catalytic mechanism of PcpA. This information may be critical to PcpA’s possible bioremediation applications.

    Subject
    Xenobiotics -- Structure-activity relationships
    Hydroquinone -- 2,6-Dichlorohydroquinone 1,2-dioxygenase (PcpA)
    Enzymes
    DNA
    Polymerase chain reaction
    Mutations
    Mutagenesis
    Pentachlorophenol
    Xenobiotics
    Science
    Academic theses
    Whitman College 2010 -- Dissertation collection -- Chemistry Department
    Genre
    Theses
    Extent
    65 pages
    Permanent URL
    http://works.whitman.edu/63
    Rights
    http://rightsstatements.org/vocab/InC/1.0/
    Contact Us

    If you have questions about permitted uses of this content, please contact the Arminda administrator: http://works.whitman.edu/contact-arminda

    7843920
    Home Whitman College Penrose Library | Arminda Collections

    Footer menu

    • About
    • Author FAQ
    • Contact Us
    • List of Collections
    • Policies
    • Terms of Use