Sandbox Reserved 325: Difference between revisions

Line 15:

Chorismate mutase is a homodimer which has an predominantly α-helical structure <ref name="pizza" />. There are 10 α-helices spread across the two monomers of chorismate mutase <ref name="pizza" />. Approximately 86% of the amino acid residues are in the α-helical formations <ref name="pizza" />. The α-helical structure of ''M. tuberculosis'' chorismate mustase similar to the chorismate mutases of ''S. cerevisae'' and ''E. coli'' <ref name="pizza" />. It holds its dimeric state in a protein concentration as low as 5 nM <ref name="pizza" />. There are no β-sheets present in chorismate mutase <ref name="CMArt2" />

Chorismate mutase is a homodimer which has a predominantly α-helical structure <ref name="pizza" />. There are 10 α-helices spread across the two monomers of chorismate mutase <ref name="pizza" />. Approximately 86% of the amino acid residues are in the α-helical formations <ref name="pizza" />. The α-helical structure of ''M. tuberculosis'' chorismate mustase similar to the chorismate mutases of ''S. cerevisae'' and ''E. coli'' <ref name="pizza" />. It holds its dimeric state in a protein concentration as low as 5 nM <ref name="pizza" />. There are no β-sheets present in chorismate mutase <ref name="CMArt2" />

Chorismate has an active site, which is used for the catalysis of the shikimate pathway <ref name="pizza" />. The <scene name='Sandbox_Reserved_325/Active_site/1'>active site</scene> is made of Arg 49,Lys 60, Arg 72, Thr 105, Glu 109, and Arg 134<ref name="pizza" />. This active site exists through electrostatic interactions with chorismate and hydrogen bonding between the amino acids <ref name="CMArt2" />. The active site forms within a single chain <ref name="pizza" />. The active site can form without any help from the second half of the dimer <ref name="pizza" />.

Line 29:

==Mechanism==

in Michaelis-Menten kinetics it has Km of 0.5 ± 0.05 mM and Kcat of 60 s-1 <ref name="pizza" />.

Chorismate mutase is an essential enzyme in the shikimate pathway <ref name="pizza"> PMID:17146044 </ref>. This pathway allows for the biosynthesis of aromatic amino acids tryptophan, tyrosine, and phenylalanine <ref name="pizza" />. The production of tyrosine and phenylalanine is achieved by what is called a Claisen rearrangement. ~~first~~ converting chorismate to prephenate. Prephenate then reacts with prephenate dehydratase and prephenate dehydrogenase which forms phenylpyruvate and hydroxyphenylpyruvate. After this occurs, aminotransferase converts hydroxy-phenylpyruvate and phenylpyruvate to phenylalanine and tyrosine. Chorismate mutase provides a 2x106 fold increase in the rate of reaction, in comparison to the uncatalyzed reaction <ref > P.D. Lyne, A.J. Mulholland, W.G. Richards. Insights into chorismate mutase catalysis from a combined qm/mm simulation of the enzyme reaction. Journal of the American Chemistry Society. 1995 117(45):11345-11350</ref>. It is the only example of an enzyme catalyzing a percyclic reaction <ref name="strat"> PMID:10960481 </ref>

Chorismate mutase is an essential enzyme in the shikimate pathway <ref name="pizza"> PMID:17146044 </ref>. This pathway allows for the biosynthesis of aromatic amino acids tryptophan, tyrosine, and phenylalanine <ref name="pizza" />. The production of tyrosine and phenylalanine is achieved by what is called a Claisen rearrangement<ref name="pizza" / >. First by converting chorismate to prephenate<ref name="pizza" />. Prephenate then reacts with prephenate dehydratase and prephenate dehydrogenase which forms phenylpyruvate and hydroxyphenylpyruvate<ref name="pizza" / >. After this occurs, aminotransferase converts hydroxy-phenylpyruvate and phenylpyruvate to phenylalanine and tyrosine <ref name="pizza" />. Chorismate mutase provides a 2x106 fold increase in the rate of reaction, in comparison to the uncatalyzed reaction <ref > P.D. Lyne, A.J. Mulholland, W.G. Richards. Insights into chorismate mutase catalysis from a combined qm/mm simulation of the enzyme reaction. Journal of the American Chemistry Society. 1995 117(45):11345-11350</ref>. It is the only example of an enzyme catalyzing a percyclic reaction <ref name="strat"> PMID:10960481 </ref>

Chorismate mutase has optimal performance at 37 degrees Celcius and at pH 7.5, but it can still optimally a pH range from pH 4.0 to 7.5 <ref name="pizza" />

Sandbox Reserved 325: Difference between revisions

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools

@@ Line 15: / Line 15: @@
 <Structure load='2f6l' size='300' frame='true' align='left' caption='Chorismate Mutase' scene='Sandbox_Reserved_325/Chainbows/1' />
-Chorismate mutase is a homodimer which has an predominantly α-helical structure <ref name="pizza" />.  There are 10 α-helices spread across the two monomers of chorismate mutase <ref name="pizza" />.  Approximately 86% of the amino acid residues are in the α-helical formations <ref name="pizza" />.  The α-helical structure of ''M. tuberculosis'' chorismate mustase similar to the chorismate mutases of ''S. cerevisae'' and ''E. coli'' <ref name="pizza" />.  It holds its dimeric state in a protein concentration as low as 5 nM <ref name="pizza" />. There are no β-sheets present in chorismate mutase <ref name="CMArt2" />
+Chorismate mutase is a homodimer which has a predominantly α-helical structure <ref name="pizza" />.  There are 10 α-helices spread across the two monomers of chorismate mutase <ref name="pizza" />.  Approximately 86% of the amino acid residues are in the α-helical formations <ref name="pizza" />.  The α-helical structure of ''M. tuberculosis'' chorismate mustase similar to the chorismate mutases of ''S. cerevisae'' and ''E. coli'' <ref name="pizza" />.  It holds its dimeric state in a protein concentration as low as 5 nM <ref name="pizza" />. There are no β-sheets present in chorismate mutase <ref name="CMArt2" />
 Chorismate has an active site, which is used for the catalysis of the shikimate pathway <ref name="pizza" />.  The <scene name='Sandbox_Reserved_325/Active_site/1'>active site</scene> is made of Arg <sub>49</sub>,Lys <sub>60</sub>, Arg <sub>72</sub>, Thr <sub>105</sub>, Glu <sub>109</sub>, and Arg <sub>134</sub><ref name="pizza" />. This active site exists through electrostatic interactions with chorismate and hydrogen bonding between the amino acids <ref name="CMArt2" />.  The active site forms within a single chain <ref name="pizza" />.  The active site can form without any help from the second half of the dimer <ref name="pizza" />.
@@ Line 29: / Line 29: @@
 ==Mechanism==
 in Michaelis-Menten kinetics it has Km of 0.5 ± 0.05 mM and Kcat of 60 s<sup>-1 </sup> <ref name="pizza" />.
-Chorismate mutase is an essential enzyme in the shikimate pathway <ref name="pizza"> PMID:17146044 </ref>.  This pathway allows for the biosynthesis of aromatic amino acids tryptophan, tyrosine, and phenylalanine <ref name="pizza" />.  The production of tyrosine and phenylalanine is achieved by what is called a Claisen rearrangement. first converting chorismate to prephenate.  Prephenate then reacts with prephenate dehydratase and prephenate dehydrogenase which forms phenylpyruvate and hydroxyphenylpyruvate.  After this occurs, aminotransferase converts hydroxy-phenylpyruvate and phenylpyruvate to phenylalanine and tyrosine.  Chorismate mutase provides a 2x10<sup>6</sup> fold increase in the rate of reaction, in comparison to the uncatalyzed reaction <ref > P.D. Lyne, A.J. Mulholland, W.G. Richards. Insights into chorismate mutase catalysis from a combined qm/mm simulation of the enzyme reaction. Journal of the American Chemistry Society. 1995 117(45):11345-11350</ref>.  It is the only example of an enzyme catalyzing a percyclic reaction <ref name="strat"> PMID:10960481 </ref>
+Chorismate mutase is an essential enzyme in the shikimate pathway <ref name="pizza"> PMID:17146044 </ref>.  This pathway allows for the biosynthesis of aromatic amino acids tryptophan, tyrosine, and phenylalanine <ref name="pizza" />.  The production of tyrosine and phenylalanine is achieved by what is called a Claisen rearrangement<ref name="pizza" / >. First by converting chorismate to prephenate<ref name="pizza" />.  Prephenate then reacts with prephenate dehydratase and prephenate dehydrogenase which forms phenylpyruvate and hydroxyphenylpyruvate<ref name="pizza" / >.  After this occurs, aminotransferase converts hydroxy-phenylpyruvate and phenylpyruvate to phenylalanine and tyrosine <ref name="pizza" />.  Chorismate mutase provides a 2x10<sup>6</sup> fold increase in the rate of reaction, in comparison to the uncatalyzed reaction <ref > P.D. Lyne, A.J. Mulholland, W.G. Richards. Insights into chorismate mutase catalysis from a combined qm/mm simulation of the enzyme reaction. Journal of the American Chemistry Society. 1995 117(45):11345-11350</ref>.  It is the only example of an enzyme catalyzing a percyclic reaction <ref name="strat"> PMID:10960481 </ref>
 Chorismate mutase has optimal performance at 37 degrees Celcius and at pH 7.5, but it can still optimally a pH range from pH 4.0 to 7.5 <ref name="pizza" />