From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1p3w.gif|left|200px]] | + | {{Seed}} |
| | + | [[Image:1p3w.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_1p3w| PDB=1p3w | SCENE= }} | | {{STRUCTURE_1p3w| PDB=1p3w | SCENE= }} |
| | | | |
| - | '''X-ray crystal structure of E. coli IscS'''
| + | ===X-ray crystal structure of E. coli IscS=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | IscS is a widely distributed cysteine desulfurase that catalyzes the pyridoxal phosphate-dependent desulfuration of L-cysteine and plays a central role in the delivery of sulfur to a variety of metabolic pathways. We report the crystal structure of Escherichia coli IscS to a resolution of 2.1A. The crystals belong to the space group P2(1)2(1)2(1) and have unit cell dimensions a=73.70A, b=101.97A, c=108.62A (alpha=beta=gamma=90 degrees ). Molecular replacement with the Thermotoga maritima NifS model was used to determine phasing, and the IscS model was refined to an R=20.6% (R(free)=23.6%) with two molecules per asymmetric unit. The structure of E.coli IscS is similar to that of T.maritima NifS with nearly identical secondary structure and an overall backbone r.m.s. difference of 1.4A. However, in contrast to NifS a peptide segment containing the catalytic cysteine residue (Cys328) is partially ordered in the IscS structure. This segment of IscS (residues 323-335) forms a surface loop directed away from the active site pocket. Cys328 is positioned greater than 17A from the pyridoxal phosphate cofactor, suggesting that a large conformational change must occur during catalysis in order for Cys328 to participate in nucleophilic attack of a pyridoxal phosphate-bound cysteine substrate. Modeling suggests that rotation of this loop may allow movement of Cys328 to within approximately 3A of the pyridoxal phosphate cofactor.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_12860127}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 12860127 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_12860127}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 28: |
Line 32: |
| | [[Category: Iron sulfur cluster]] | | [[Category: Iron sulfur cluster]] |
| | [[Category: Nif]] | | [[Category: Nif]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 04:39:15 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 23:00:57 2008'' |
Revision as of 20:01, 28 July 2008
Template:STRUCTURE 1p3w
X-ray crystal structure of E. coli IscS
Template:ABSTRACT PUBMED 12860127
About this Structure
1P3W is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of IscS, a cysteine desulfurase from Escherichia coli., Cupp-Vickery JR, Urbina H, Vickery LE, J Mol Biol. 2003 Jul 25;330(5):1049-59. PMID:12860127
Page seeded by OCA on Mon Jul 28 23:00:57 2008
