2oov: Difference between revisions

Revision as of 19:20, 21 February 2008

Crystal Structure of Hansenula polymorpha amine oxidase to 1.7 Angstroms

OverviewOverview

The accessibility of large substrates to buried enzymatic active sites is dependent upon the utilization of proteinaceous channels. The necessity of these channels in the case of small substrates is questionable because diffusion through the protein matrix is often assumed. Copper amine oxidases contain a buried protein-derived quinone cofactor and a mononuclear copper center that catalyze the conversion of two substrates, primary amines and molecular oxygen, to aldehydes and hydrogen peroxide, respectively. The nature of molecular oxygen migration to the active site in the enzyme from Hansenula polymorpha is explored using a combination of kinetic, x-ray crystallographic, and computational approaches. A crystal structure of H. polymorpha amine oxidase in complex with xenon gas, which serves as an experimental probe for molecular oxygen binding sites, reveals buried regions of the enzyme suitable for transient molecular oxygen occupation. Calculated O(2) free energy maps using copper amine oxidase crystal structures in the absence of xenon correspond well with later experimentally observed xenon sites in these systems, and allow the visualization of O(2) migration routes of differing probabilities within the protein matrix. Site-directed mutagenesis designed to block individual routes has little effect on overall k(cat)/K(m) (O(2)), supporting multiple dynamic pathways for molecular oxygen to reach the active site.

About this StructureAbout this Structure

2OOV is a Protein complex structure of sequences from Pichia angusta with , and as ligands. Active as Amine oxidase (copper-containing), with EC number 1.4.3.6 Full crystallographic information is available from OCA.

ReferenceReference

Exploring molecular oxygen pathways in Hansenula polymorpha copper-containing amine oxidase., Johnson BJ, Cohen J, Welford RW, Pearson AR, Schulten K, Klinman JP, Wilmot CM, J Biol Chem. 2007 Jun 15;282(24):17767-76. Epub 2007 Apr 4. PMID:17409383

Page seeded by OCA on Thu Feb 21 18:20:53 2008

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OCA

@@ Line 4: / Line 4: @@
 ==Overview==
-The accessibility of large substrates to buried enzymatic active sites is, dependent upon the utilization of proteinaceous channels. The necessity of, these channels in the case of small substrates is questionable because, diffusion through the protein matrix is often assumed. Copper amine, oxidases contain a buried protein-derived quinone cofactor and a, mononuclear copper center that catalyze the conversion of two substrates, primary amines and molecular oxygen, to aldehydes and hydrogen peroxide, respectively. The nature of molecular oxygen migration to the active site, in the enzyme from Hansenula polymorpha is explored using a combination of, kinetic, x-ray crystallographic, and computational approaches. A crystal, structure of H. polymorpha amine oxidase in complex with xenon gas, which, serves as an experimental probe for molecular oxygen binding sites, reveals buried regions of the enzyme suitable for transient molecular, oxygen occupation. Calculated O(2) free energy maps using copper amine, oxidase crystal structures in the absence of xenon correspond well with, later experimentally observed xenon sites in these systems, and allow the, visualization of O(2) migration routes of differing probabilities within, the protein matrix. Site-directed mutagenesis designed to block individual, routes has little effect on overall k(cat)/K(m) (O(2)), supporting, multiple dynamic pathways for molecular oxygen to reach the active site.
+The accessibility of large substrates to buried enzymatic active sites is dependent upon the utilization of proteinaceous channels. The necessity of these channels in the case of small substrates is questionable because diffusion through the protein matrix is often assumed. Copper amine oxidases contain a buried protein-derived quinone cofactor and a mononuclear copper center that catalyze the conversion of two substrates, primary amines and molecular oxygen, to aldehydes and hydrogen peroxide, respectively. The nature of molecular oxygen migration to the active site in the enzyme from Hansenula polymorpha is explored using a combination of kinetic, x-ray crystallographic, and computational approaches. A crystal structure of H. polymorpha amine oxidase in complex with xenon gas, which serves as an experimental probe for molecular oxygen binding sites, reveals buried regions of the enzyme suitable for transient molecular oxygen occupation. Calculated O(2) free energy maps using copper amine oxidase crystal structures in the absence of xenon correspond well with later experimentally observed xenon sites in these systems, and allow the visualization of O(2) migration routes of differing probabilities within the protein matrix. Site-directed mutagenesis designed to block individual routes has little effect on overall k(cat)/K(m) (O(2)), supporting multiple dynamic pathways for molecular oxygen to reach the active site.
 ==About this Structure==
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 [[Category: Pichia angusta]]
 [[Category: Protein complex]]
-[[Category: Johnson, B.J.]]
+[[Category: Johnson, B J.]]
-[[Category: Wilmot, C.M.]]
+[[Category: Wilmot, C M.]]
 [[Category: CU]]
 [[Category: GOL]]
@@ Line 23: / Line 23: @@
 [[Category: tpq]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jan 23 14:28:49 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:20:53 2008''