1beu: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1beu.gif|left|200px]] | [[Image:1beu.gif|left|200px]] | ||
'''TRP SYNTHASE (D60N-IPP-SER) WITH K+''' | {{Structure | ||
|PDB= 1beu |SIZE=350|CAPTION= <scene name='initialview01'>1beu</scene>, resolution 1.9Å | |||
|SITE= <scene name='pdbsite=NUA:Substrate+Analog+Bound+To+The+Alpha+Active+Site'>NUA</scene> and <scene name='pdbsite=NUB:Reaction+Intermediate+Bound+To+The+Beta+Active+Site'>NUB</scene> | |||
|LIGAND= <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=IPL:INDOLE-3-PROPANOL+PHOSPHATE'>IPL</scene> and <scene name='pdbligand=PLS:[3-HYDROXY-2-METHYL-5-PHOSPHONOOXYMETHYL-PYRIDIN-4-YLMETHYL]-SERINE'>PLS</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] | |||
|GENE= TRPA/TRPB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=602 Salmonella typhimurium]) | |||
}} | |||
'''TRP SYNTHASE (D60N-IPP-SER) WITH K+''' | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
1BEU is a [ | 1BEU is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Salmonella_typhimurium Salmonella typhimurium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BEU OCA]. | ||
==Reference== | ==Reference== | ||
Cryocrystallography and microspectrophotometry of a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex reveals allosteric roles of alpha Asp60., Rhee S, Miles EW, Mozzarelli A, Davies DR, Biochemistry. 1998 Jul 28;37(30):10653-9. PMID:[http:// | Cryocrystallography and microspectrophotometry of a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex reveals allosteric roles of alpha Asp60., Rhee S, Miles EW, Mozzarelli A, Davies DR, Biochemistry. 1998 Jul 28;37(30):10653-9. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/9692955 9692955] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Salmonella typhimurium]] | [[Category: Salmonella typhimurium]] | ||
| Line 26: | Line 35: | ||
[[Category: mutation d60n in a-subunit]] | [[Category: mutation d60n in a-subunit]] | ||
''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 10:10:04 2008'' | ||
Revision as of 11:10, 20 March 2008
| |||||||
| , resolution 1.9Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | and | ||||||
| Ligands: | , and | ||||||
| Gene: | TRPA/TRPB (Salmonella typhimurium) | ||||||
| Activity: | Tryptophan synthase, with EC number 4.2.1.20 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
TRP SYNTHASE (D60N-IPP-SER) WITH K+
OverviewOverview
We have investigated the role of Asp60 of the alpha-subunit in allosteric communication between the tryptophan synthase alpha- and beta-subunits. Crystallographic and microspectrophotometric studies have been carried out on a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex which has no observable alpha-activity, but has substantial beta-activity. Single-crystal polarized absorption spectra indicate that the external aldimine is the predominant L-serine intermediate and that the amount of the intermediate formed is independent of pH, monovalent cations, and allosteric effectors. The three-dimensional structure is reported for this mutant enzyme complexed with indole 3-propanol phosphate bound to the alpha-site and L-serine bound to the beta-site (alpha D60N-IPP-Ser), and this structure is compared with that of the unliganded mutant enzyme (alpha D60N). In the complex, L-serine forms a stable external aldimine with the pyridoxal phosphate coenzyme at the active site of the beta-subunit. The conformation of the unliganded mutant is almost identical to that of the wild type enzyme. However, the structure of the mutant complexed with IPP and serine exhibits ligand-induced conformational changes much smaller than those observed previously for another mutant enzyme in the presence of the same ligands (beta K87T-IPP-Ser) [Rhee, S., Parris, K. D., Hyde, C. C., Ahmed, S. A., Miles, E. W., and Davies, D. R. (1997) Biochemistry 36, 7664-7680]. The alpha D60N-IPP-Ser alpha 2 beta 2 complex does not undergo the following ligand-induced conformational changes: (1) the closure of the alpha-subunit loop 6 (residues 178-191), (2) the movement of the mobile subdomain (residues 93-189) of the beta-subunit, and (3) the rotation of the alpha-subunit relative to the beta-subunit. These observations show that alpha Asp60 plays important roles in the closure of loop 6 and in allosteric communication between the alpha- and beta-subunits.
About this StructureAbout this Structure
1BEU is a Protein complex structure of sequences from Salmonella typhimurium. Full crystallographic information is available from OCA.
ReferenceReference
Cryocrystallography and microspectrophotometry of a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex reveals allosteric roles of alpha Asp60., Rhee S, Miles EW, Mozzarelli A, Davies DR, Biochemistry. 1998 Jul 28;37(30):10653-9. PMID:9692955
Page seeded by OCA on Thu Mar 20 10:10:04 2008