Sandbox Reserved 768: Difference between revisions

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The catalytic domain contains the active site of the enzyme. It is composed of 13 α-helices and 8 β-strands <ref name= "fusetti"/> and houses the binding sites for the nonheme iron atom, the cofactor, and substrate. The iron binds to two histidines (His285 and His290 in hPAH) and a glutamate (Glu330) in the deep cleft in the core of each monomer. <ref name= "flydal"/>.
The catalytic domain contains the active site of the enzyme. It is composed of 13 α-helices and 8 β-strands <ref name= "fusetti"/> and houses the binding sites for the nonheme iron atom, the cofactor, and substrate. The iron binds to two histidines (His285 and His290 in hPAH) and a glutamate (Glu330) in the deep cleft in the core of each monomer. <ref name= "flydal"/>.
<Structure load='1j8u' size='500' frame='true' align='right' caption='The assembly of PheOH might be described by a domain swapping mechanism in which secondary structural elements mutually switch their position to promote oligomerization' scene='Insert optional scene name here' />


The C-terminal oligomerization or tetramerization domain begins with an antiparallel-sheet
The C-terminal oligomerization or tetramerization domain begins with an antiparallel-sheet
(residues 411–414, 421–424)  
(residues 411–414, 421–424)  
and is formed by a C-terminal “arm” consisting of two β-strands, forming a β-ribbon, and a 40 Å long α-helix. This C-terminal arm extends over an adjacent monomer, thus bringing the four helices (one from each monomer) into a closely packed anti-parallel coiled-coil motif in the center of the structure (as can be seen in the tetramer structure above). <ref name= "fusetti"/>. The assembly of the enzyme occurs through a swapping mechanism in which the secondary structural elements mutually switch their position to promote oligomerization. <ref name= "fusetti"/>.
and is formed by a C-terminal “arm” consisting of two β-strands, forming a β-ribbon, and a 40 Å long α-helix. This C-terminal arm extends over an adjacent monomer, thus bringing the four helices (one from each monomer) into a closely packed anti-parallel coiled-coil motif in the center of the structure (as can be seen in the tetramer structure above). <ref name= "fusetti"/>. The assembly of the enzyme occurs through a swapping mechanism in which the secondary structural elements mutually switch their position to promote oligomerization. <ref name= "fusetti"/>.