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1k8z
From Proteopedia
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|PDB= 1k8z |SIZE=350|CAPTION= <scene name='initialview01'>1k8z</scene>, resolution 1.70Å | |PDB= 1k8z |SIZE=350|CAPTION= <scene name='initialview01'>1k8z</scene>, resolution 1.70Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= | + | |LIGAND= <scene name='pdbligand=IAG:N-[1H-INDOL-3-YL-ACETYL]GLYCINE+ACID'>IAG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5'-PHOSPHATE'>PLP</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Tryptophan_synthase Tryptophan synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.20 4.2.1.20] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Tryptophan_synthase Tryptophan synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.20 4.2.1.20] </span> |
|GENE= TRPA/TRPB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=602 Salmonella typhimurium]) | |GENE= TRPA/TRPB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=602 Salmonella typhimurium]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1k7x|1K7X]], [[1k8y|1K8Y]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1k8z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1k8z OCA], [http://www.ebi.ac.uk/pdbsum/1k8z PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1k8z RCSB]</span> | ||
}} | }} | ||
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[[Category: Schlichting, I.]] | [[Category: Schlichting, I.]] | ||
[[Category: Weyand, M.]] | [[Category: Weyand, M.]] | ||
| - | [[Category: IAG]] | ||
| - | [[Category: NA]] | ||
| - | [[Category: PLP]] | ||
[[Category: carbon-oxygen lyase]] | [[Category: carbon-oxygen lyase]] | ||
[[Category: pyridoxal phosphate]] | [[Category: pyridoxal phosphate]] | ||
[[Category: tryptophan biosynthesis]] | [[Category: tryptophan biosynthesis]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:45:02 2008'' |
Revision as of 18:45, 30 March 2008
| |||||||
| , resolution 1.70Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Gene: | TRPA/TRPB (Salmonella typhimurium) | ||||||
| Activity: | Tryptophan synthase, with EC number 4.2.1.20 | ||||||
| Related: | 1K7X, 1K8Y
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE TRYPTOPHAN SYNTHASE BETA-SER178PRO MUTANT COMPLEXED WITH N-[1H-INDOL-3-YL-ACETYL]GLYCINE ACID
Overview
The catalytic activity of the pyridoxal 5'-phosphate-dependent tryptophan synthase alpha(2)beta(2) complex is allosterically regulated. The hydrogen bond between the helix betaH6 residue betaSer(178) and the loop alphaL6 residue Gly(181) was shown to be critical in ligand-induced intersubunit signaling, with the alpha-beta communication being completely lost in the mutant betaSer(178) --> Pro (Marabotti, A., De Biase, D., Tramonti, A., Bettati, S., and Mozzarelli, A. (2001) J. Biol. Chem. 276, 17747-17753). The structural basis of the impaired allosteric regulation was investigated by determining the crystal structures of the mutant betaSer(178) --> Pro in the absence and presence of the alpha-subunit ligands indole-3-acetylglycine and glycerol 3-phosphate. The mutation causes local and distant conformational changes especially in the beta-subunit. The ligand-free structure exhibits larger differences at the N-terminal part of helix betaH6, whereas the enzyme ligand complexes show differences at the C-terminal side. In contrast to the wild-type enzyme loop alphaL6 remains in an open conformation even in the presence of alpha-ligands. This effects the equilibrium between active and inactive conformations of the alpha-active site, altering k(cat) and K(m), and forms the structural basis for the missing allosteric communication between the alpha- and beta-subunits.
About this Structure
1K8Z is a Protein complex structure of sequences from Salmonella typhimurium. Full crystallographic information is available from OCA.
Reference
Crystal structure of the beta Ser178--> Pro mutant of tryptophan synthase. A "knock-out" allosteric enzyme., Weyand M, Schlichting I, Herde P, Marabotti A, Mozzarelli A, J Biol Chem. 2002 Mar 22;277(12):10653-60. Epub 2001 Dec 26. PMID:11756454
Page seeded by OCA on Sun Mar 30 21:45:02 2008
