Sandbox Reserved 642: Difference between revisions

From Proteopedia
Jump to navigationJump to search
No edit summary
No edit summary
Line 10: Line 10:
== '''Structure''' ==
== '''Structure''' ==
<Structure load='2PAH_tetramer3.pdb' size='500' frame='true' align='right' caption='This is a model of the pheylalanine hydroxylase dimer as found in humans. The green ball in within each subunit represents the iron ion in the catalytic domains.' scene='Insert optional scene name here' />  
<Structure load='2PAH_tetramer3.pdb' size='500' frame='true' align='right' caption='This is a model of the pheylalanine hydroxylase dimer as found in humans. The green ball in within each subunit represents the iron ion in the catalytic domains.' scene='Insert optional scene name here' />  
PheOH can exist as a dimer or tetramer with identical subunits. Each subunit is organized  to have a regulatory, catalytic and tetramerization domain. The native form of human PheOH has an estimated secondary structure composed 48% alpha-helices, 28% extended structures, 12% beta-turns, and 12% non-structured conformations. The more structured elements are usually concentrated in the catalytic C-terminal domain of the protein, while the more flexible and unstructured elements are grouped in the regulatory N-terminal domain.<ref> Chehin, R., M. Thorolfsson, PM. Knappskog, A. Martinez, T. Flatmark, JL. Arrondo, and A. Muga,Domain structure and stability of human phenylalanine hydroxylase inferred from infrared spectroscopy[http://www.ncbi.nlm.nih.gov/pubmed/9490012]</ref> The active site of PheOH can be found in the center of the catalytic domain and is characterized by a 13 Angstroms deep and 10 Angstroms wide hydrophobic pocket. Lining the active site are 3 glutamates, 2 histadines and 1 tyrosine residues. The center of each catalytic domain consists of an iron ion which is vital to the enzyme activity and binds to  histadine residues 285 and 290, 1 oxygen atom in glutamate 330. The PheOH model protein was generated via x-ray crystallography.<ref> Erlandsen H., DirSci; Marianne G. Patch, PhD; Alejandra Gamez, PhD; Mary Straub; and Raymond C. Stevens, PhD. Structural Studies on Phenylalanine Hydroxylase and Implications Toward Understanding and Treating Phenylketonuria [http://www.pkuworld.org/home/docs/literature/erlandsen_2003_p.pdf]</ref>  
PheOH can exist as a dimer or tetramer with identical subunits. Each subunit is organized  to have a regulatory, catalytic and tetramerization domain. The native form of human PheOH has an estimated secondary structure composed 48% alpha-helices, 28% extended structures, 12% beta-turns, and 12% non-structured conformations. The more structured elements are usually concentrated in the catalytic C-terminal domain of the protein, while the more flexible and unstructured elements are grouped in the regulatory N-terminal domain.<ref> Chehin, R., M. Thorolfsson, PM. Knappskog, A. Martinez, T. Flatmark, JL. Arrondo, and A. Muga,Domain structure and stability of human phenylalanine hydroxylase inferred from infrared spectroscopy[http://www.ncbi.nlm.nih.gov/pubmed/9490012]</ref> The active site of PheOH can be found in the center of the catalytic domain and is characterized by a 13 Angstroms deep and 10 Angstroms wide hydrophobic pocket. Lining the active site are 3 glutamates, 2 histadines and 1 tyrosine residues. The center of each catalytic domain consists of an iron ion which is vital to the enzyme activity and binds to  <scene name='Sandbox_Reserved_642/Iron_binding/2'>histadine residues 285 and 290, 1 oxygen atom in glutamate 330</scene>. The PheOH model protein was generated via x-ray crystallography.<ref> Erlandsen H., DirSci; Marianne G. Patch, PhD; Alejandra Gamez, PhD; Mary Straub; and Raymond C. Stevens, PhD. Structural Studies on Phenylalanine Hydroxylase and Implications Toward Understanding and Treating Phenylketonuria [http://www.pkuworld.org/home/docs/literature/erlandsen_2003_p.pdf]</ref>