Sandbox Reserved 1068: Difference between revisions

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==Molecular Mechanism==

'''Magnesium cation effect'''

[[Image:Screen Shot 2015-04-25 at 11.08.58 PM.png‎ |300 px|left|thumb|'''Table 1:''' pKa values of active site residues of MbtI with and without Magnesium. Ferrer 2-11.]] The presence of the [http://en.wikipedia.org/wiki/Magnesium_in_biology magnesium ion] induces <scene name='69/694235/Mg_coordination/1'>changes in the structure</scene> of the active site and in the substrate, as well as causes significant pKa shifts in some of the key residues involved in the catalytic activity(Table 1) . The coordination shell of the magnesium cation in the active site of MbtI is composed of two water molecules, Glu434, Glu294, and the two oxygen atoms of the C1 carboxylate group of chorismate <ref name= "8a">PMID:22307014</ref>. In the presence of the magnesium ion, the positively charged Lys295 is displaced from the active site and the negatively charged Glu297 is faced toward the active site. Magnesium cation also orients the C1 carboxylate group coplanar to the ring of chorismate, reducing the electron density on the C2 center and favoring nucleophilic attack.

[[Image:Screen Shot 2015-04-25 at 11.08.58 PM.png‎ |300 px|left|thumb|'''Table 1:''' pKa values of active site residues of MbtI with and without Magnesium. Ferrer 2-11.]] The presence of the [http://en.wikipedia.org/wiki/Magnesium_in_biology magnesium ion] induces <scene name='69/694235/Mg_coordination/1'>changes in the structure</scene> of the active site and in the substrate, as well as causes significant pKa shifts in some of the key residues involved in the catalytic activity(Table 1) . The <scene name='69/694235/3rv6_mg_shell/3'>coordination shell</scene> of the magnesium cation in the active site of MbtI is composed of two water molecules, Glu434, Glu294, and the two oxygen atoms of the C1 carboxylate group of chorismate <ref name= "8a">PMID:22307014</ref>. In the presence of the magnesium ion, the positively charged Lys295 is displaced from the active site and the negatively charged Glu297 is faced toward the active site. Magnesium cation also orients the C1 carboxylate group coplanar to the ring of chorismate, reducing the electron density on the C2 center and favoring nucleophilic attack.

'''Isochorismate pyruvate lyase (IPL)'''

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@@ Line 25: / Line 25: @@
 ==Molecular Mechanism==
 '''Magnesium cation effect'''
-[[Image:Screen Shot 2015-04-25 at 11.08.58 PM.png‎ |300 px|left|thumb|'''Table 1:''' pKa values of active site residues of MbtI with and without Magnesium.  Ferrer 2-11.]] The presence of the [http://en.wikipedia.org/wiki/Magnesium_in_biology magnesium ion] induces <scene name='69/694235/Mg_coordination/1'>changes in the structure</scene> of the active site and in the substrate, as well as causes significant pKa shifts in some of the key residues involved in the catalytic activity(Table 1) . The coordination shell of the magnesium cation in the active site of MbtI is composed of two water molecules, Glu434, Glu294, and the two oxygen atoms of the C1 carboxylate group of chorismate <ref name= "8a">PMID:22307014</ref>. In the presence of the magnesium ion, the positively charged Lys295 is displaced from the active site and the negatively charged Glu297 is faced toward the active site. Magnesium cation also orients the C1 carboxylate group coplanar to the ring of chorismate, reducing the electron density on the C2 center and favoring nucleophilic attack.
+[[Image:Screen Shot 2015-04-25 at 11.08.58 PM.png‎ |300 px|left|thumb|'''Table 1:''' pKa values of active site residues of MbtI with and without Magnesium.  Ferrer 2-11.]] The presence of the [http://en.wikipedia.org/wiki/Magnesium_in_biology magnesium ion] induces <scene name='69/694235/Mg_coordination/1'>changes in the structure</scene> of the active site and in the substrate, as well as causes significant pKa shifts in some of the key residues involved in the catalytic activity(Table 1) . The <scene name='69/694235/3rv6_mg_shell/3'>coordination shell</scene> of the magnesium cation in the active site of MbtI is composed of two water molecules, Glu434, Glu294, and the two oxygen atoms of the C1 carboxylate group of chorismate <ref name= "8a">PMID:22307014</ref>. In the presence of the magnesium ion, the positively charged Lys295 is displaced from the active site and the negatively charged Glu297 is faced toward the active site. Magnesium cation also orients the C1 carboxylate group coplanar to the ring of chorismate, reducing the electron density on the C2 center and favoring nucleophilic attack.
 '''Isochorismate pyruvate lyase (IPL)'''