rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Identification of structural changes associated with regulation of tyrosine hydroxylase
  name:
    name part: Wang, Shanzhi.
    role:
      role term: creator
  name:
    name part: Fitzpatrick, Paul F.
    role:
      role term: thesis advisor.
  name:
    name part: Reinhart, Gregory D.
    role:
      role term: thesis advisor.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2011
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: remote
    extent: 1 online resource.
  abstract: Tyrosine hydroxylase (TyrH) is the first and rate-limiting enzyme of catecholamine synthetic pathway, and its regulation is critical for controlling catecholamine synthesis. The well recognized regulatory mechanisms are inhibition by catecholamine binding and re-activation upon Ser40 phosphorylation. Catecholamines bind to TyrH tightly, while phosphorylation of TyrH at Ser40 decreases the binding affinity by several hundred-fold. Regulation of TyrH is accompanied by conformational changes of the protein. This study focuses on the identification of the conformational changes of TyrH upon dopamine binding and Ser40 phosphorylation, using hydrogen deuterium exchange mass spectrometry (HDMS) and fluorescence spectroscopy. HDMS identifies three peptides undergoing conformational changes upon dopamine binding, peptide 35-41, 42-71 and 295-299. Peptides 35-41 and 42-71 are on the regulatory domain, while peptide 295-299 is at the active site entrance. Upon dopamine binding, all three peptides are protected from exchange; phosphorylation of TyrH at Ser40 has opposite effects on the exchange kinetics of peptide 295-299, but peptides 35-41 and 42-71 could not be detected by MS after phosphorylation. This suggests that the structural effects of dopamine binding and Ser40 phosphorylation are opposite. The fluorescence spectroscopy of mutant enzymes containing a single tryptophan at position 14, 34 or 74 was performed before and after phosphorylation. F34W/F3W TyrH has a significant decrease in steady-state fluorescence anisotropy, an increase in the bimolecular quenching rate constant kq and dynamic anisotropy upon phosphorylation at Ser40, while F14W/F3W TyrH and F74W/F3W TyrH exhibit much smaller differences. This suggests that phosphorylation of TyrH at Ser40 increases the flexibility of the regulatory domain. The results are consistent with TyrH existing in two conformations, a closed conformation stabilized by dopamine in which the N-terminal regulator domain of TyrH cover…
  note: by Shanzhi Wang.
  note: "Major Subject: Biochemistry"
  note: Title from author supplied metadata (automated record created 2011-11-01 09:04:20).
  note: Electronic resource.
  note: Doctor of Philosophy Texas A&M University 2010 http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8208
  note: Includes bibliographical references.
  note: Text (Dissertation)
  subject:
    topic: Major biochemistry
  subject:
    topic: Conformational change
  subject:
    topic: Activation
  subject:
    topic: Enzyme
  subject:
    topic: Inhibition
  subject:
    topic: Tyrosine hydroxylase
  subject:
    topic: Catecholamine
  subject:
    topic: Regulation
  identifier: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8208
  record info:
    record content source: TXA
    record creation date: 111108
    record change date: 20151202144028.0
    record identifier: in00002736723