1sjb
From Proteopedia
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| - | [[Image:1sjb.gif|left|200px]] | + | [[Image:1sjb.gif|left|200px]] |
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| - | '''X-ray structure of o-succinylbenzoate synthase complexed with o-succinylbenzoic acid''' | + | {{Structure |
| + | |PDB= 1sjb |SIZE=350|CAPTION= <scene name='initialview01'>1sjb</scene>, resolution 2.20Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene> and <scene name='pdbligand=OSB:2-SUCCINYLBENZOATE'>OSB</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= AAAR ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=37632 Amycolatopsis sp.]) | ||
| + | }} | ||
| + | |||
| + | '''X-ray structure of o-succinylbenzoate synthase complexed with o-succinylbenzoic acid''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1SJB is a [ | + | 1SJB is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Amycolatopsis_sp. Amycolatopsis sp.]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SJB OCA]. |
==Reference== | ==Reference== | ||
| - | Evolution of enzymatic activity in the enolase superfamily: structural studies of the promiscuous o-succinylbenzoate synthase from Amycolatopsis., Thoden JB, Taylor Ringia EA, Garrett JB, Gerlt JA, Holden HM, Rayment I, Biochemistry. 2004 May 18;43(19):5716-27. PMID:[http:// | + | Evolution of enzymatic activity in the enolase superfamily: structural studies of the promiscuous o-succinylbenzoate synthase from Amycolatopsis., Thoden JB, Taylor Ringia EA, Garrett JB, Gerlt JA, Holden HM, Rayment I, Biochemistry. 2004 May 18;43(19):5716-27. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15134446 15134446] |
[[Category: Amycolatopsis sp.]] | [[Category: Amycolatopsis sp.]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: racemase]] | [[Category: racemase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 14:05:40 2008'' |
Revision as of 12:05, 20 March 2008
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| , resolution 2.20Å | |||||||
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| Ligands: | and | ||||||
| Gene: | AAAR (Amycolatopsis sp.) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
X-ray structure of o-succinylbenzoate synthase complexed with o-succinylbenzoic acid
Overview
Divergent evolution of enzyme function is commonly explained by a gene duplication event followed by mutational changes that allow the protein encoded by the copy to acquire a new function. An alternate hypothesis is that this process is facilitated when the progenitor enzyme acquires a second function while maintaining the original activity. This phenomenon has been suggested to occur in the o-succinylbenzoate synthase (OSBS) from a species of Amycolatopsis that catalyzes not only the physiological syn-dehydration reaction of 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate but also an accidental racemization of N-acylamino acids [Palmer, D. R., Garrett, J. B., Sharma, V., Meganathan, R., Babbitt, P. C., and Gerlt, J. A. (1999) Biochemistry 38, 4252-4258]. To understand the molecular basis of this promiscuity, three-dimensional structures of liganded complexes of this enzyme have been determined, including the product of the OSBS reaction and three N-acylamino acid substrates for the N-acylamino acid racemase (NAAAR) reaction, N-acetylmethionine, N-succinylmethionine, and N-succinylphenylglycine, to 2.2, 2.3, 2.1, and 1.9 A resolution, respectively. These structures show how the active-site cavity can accommodate both the hydrophobic substrate for the OSBS reaction and the substrates for the accidental NAAAR reaction. As expected, the N-acylamino acid is sandwiched between lysines 163 and 263, which function as the catalytic bases for the abstraction of the alpha-proton in the (R)- and (S)-racemization reactions, respectively [Taylor Ringia, E. A., Garrett, J. B, Thoden, J. B., Holden, H. M., Rayment, I., and Gerlt, J. A. (2004) Biochemistry 42, 224-229]. Importantly, the protein forms specific favorable interactions with the hydrophobic amino acid side chain, alpha-carbon, carboxylate, and the polar components of the N-acyl linkage. Accommodation of the components of the N-acyl linkage appears to be the reason that this enzyme is capable of a racemization reaction on these substrates, whereas the orthologous OSBS from Escherichia coli lacks this functionality.
About this Structure
1SJB is a Single protein structure of sequence from Amycolatopsis sp.. Full crystallographic information is available from OCA.
Reference
Evolution of enzymatic activity in the enolase superfamily: structural studies of the promiscuous o-succinylbenzoate synthase from Amycolatopsis., Thoden JB, Taylor Ringia EA, Garrett JB, Gerlt JA, Holden HM, Rayment I, Biochemistry. 2004 May 18;43(19):5716-27. PMID:15134446
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