From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
Line 1: |
Line 1: |
- | [[Image:1h5r.gif|left|200px]] | + | {{Seed}} |
| + | [[Image:1h5r.png|left|200px]] |
| | | |
| <!-- | | <!-- |
Line 9: |
Line 10: |
| {{STRUCTURE_1h5r| PDB=1h5r | SCENE= }} | | {{STRUCTURE_1h5r| PDB=1h5r | SCENE= }} |
| | | |
- | '''THYMIDYLYLTRANSFERASE COMPLEXED WITH THIMIDINE AND GLUCOSE-1-PHOSPATE'''
| + | ===THYMIDYLYLTRANSFERASE COMPLEXED WITH THIMIDINE AND GLUCOSE-1-PHOSPATE=== |
| | | |
| | | |
- | ==Overview==
| + | <!-- |
- | Glucose-1-phosphate thymidylyltransferase is the first enzyme in the biosynthesis of dTDP-l-rhamnose, the precursor of l-rhamnose, an essential component of surface antigens, such as the O-lipopolysaccharide, mediating virulence and adhesion to host tissues in many microorganisms. The enzyme catalyses the formation of dTDP-glucose, from dTTP and glucose 1-phosphate, as well as its pyrophosphorolysis. To shed more light on the catalytic properties of glucose-1-phosphate thymidylyltransferase from Escherichia coli, specifically distinguishing between ping pong and sequential ordered bi bi reaction mechanisms, the enzyme kinetic properties have been analysed in the presence of different substrates and inhibitors. Moreover, three different complexes of glucose-1-phosphate thymidylyltransferase (co-crystallized with dTDP, with dTMP and glucose-1-phosphate, with d-thymidine and glucose-1-phosphate) have been analysed by X-ray crystallography, in the 1.9-2.3 A resolution range (R-factors of 17.3-17.5 %). The homotetrameric enzyme shows strongly conserved substrate/inhibitor binding modes in a surface cavity next to the topological switch-point of a quasi-Rossmann fold. Inspection of the subunit tertiary structure reveals relationships to other enzymes involved in the biosynthesis of nucleotide-sugars, including distant proteins such as the molybdenum cofactor biosynthesis protein MobA. The precise location of the substrate relative to putative reactive residues in the catalytic center suggests that, in keeping with the results of the kinetic measurements, both catalysed reactions, i.e. dTDP-glucose biosynthesis and pyrophosphorolysis, follow a sequential ordered bi bi catalytic mechanism.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_11697907}}, adds the Publication Abstract to the page |
| + | (as it appears on PubMed at http://www.pubmed.gov), where 11697907 is the PubMed ID number. |
| + | --> |
| + | {{ABSTRACT_PUBMED_11697907}} |
| | | |
| ==About this Structure== | | ==About this Structure== |
Line 28: |
Line 32: |
| [[Category: Pyrophosphatase]] | | [[Category: Pyrophosphatase]] |
| [[Category: Transferase]] | | [[Category: Transferase]] |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 18:28:03 2008'' | + | |
| + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 1 06:40:20 2008'' |
Revision as of 03:40, 1 July 2008
Template:STRUCTURE 1h5r
THYMIDYLYLTRANSFERASE COMPLEXED WITH THIMIDINE AND GLUCOSE-1-PHOSPATE
Template:ABSTRACT PUBMED 11697907
About this Structure
1H5R is a Protein complex structure. Full crystallographic information is available from OCA.
Reference
Kinetic and crystallographic analyses support a sequential-ordered bi bi catalytic mechanism for Escherichia coli glucose-1-phosphate thymidylyltransferase., Zuccotti S, Zanardi D, Rosano C, Sturla L, Tonetti M, Bolognesi M, J Mol Biol. 2001 Nov 2;313(4):831-43. PMID:11697907
Page seeded by OCA on Tue Jul 1 06:40:20 2008