From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:2bes.jpg|left|200px]] | + | {{Seed}} |
| | + | [[Image:2bes.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_2bes| PDB=2bes | SCENE= }} | | {{STRUCTURE_2bes| PDB=2bes | SCENE= }} |
| | | | |
| - | '''STRUCTURE OF MYCOBACTERIUM TUBERCULOSIS RIBOSE-5-PHOSPHATE ISOMERASE, RPIB, RV2465C, IN COMPLEX WITH 4-PHOSPHO-D-ERYTHRONOHYDROXAMIC ACID.'''
| + | ===STRUCTURE OF MYCOBACTERIUM TUBERCULOSIS RIBOSE-5-PHOSPHATE ISOMERASE, RPIB, RV2465C, IN COMPLEX WITH 4-PHOSPHO-D-ERYTHRONOHYDROXAMIC ACID.=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | Ribose-5-phosphate isomerase (Rpi), an important enzyme in the pentose phosphate pathway, catalyzes the interconversion of ribulose 5-phosphate and ribose 5-phosphate. Two unrelated isomerases have been identified, RpiA and RpiB, with different structures and active site residues. The reaction catalyzed by both enzymes is thought to proceed via a high energy enediolate intermediate, by analogy to other carbohydrate isomerases. Here we present studies of RpiB from Mycobacterium tuberculosis together with small molecules designed to resemble the enediolate intermediate. The relative affinities of these inhibitors for RpiB have a different pattern than that observed previously for the RpiA from spinach. X-ray structures of RpiB in complex with the inhibitors 4-phospho-d-erythronohydroxamic acid (K(m) 57 microm) and 4-phospho-d-erythronate (K(i) 1.7 mm) refined to resolutions of 2.1 and 2.2 A, respectively, allowed us to assign roles for most active site residues. These results, combined with docking of the substrates in the position of the most effective inhibitor, now allow us to outline the reaction mechanism for RpiBs. Both enzymes have residues that can catalyze opening of the furanose ring of the ribose 5-phosphate and so can improve the efficiency of the reaction. Both enzymes also have an acidic residue that acts as a base in the isomerization step. A lysine residue in RpiAs provides for more efficient stabilization of the intermediate than the corresponding uncharged groups of RpiBs; this same feature lies behind the more efficient binding of RpiA to 4-phospho-d-erythronate.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_15590681}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 15590681 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_15590681}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 31: |
Line 35: |
| | [[Category: Phosphopentosisomerase]] | | [[Category: Phosphopentosisomerase]] |
| | [[Category: Ribose 5-phosphate epimerase]] | | [[Category: Ribose 5-phosphate epimerase]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 20:11:35 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 15:10:06 2008'' |
Revision as of 12:10, 28 July 2008
Template:STRUCTURE 2bes
STRUCTURE OF MYCOBACTERIUM TUBERCULOSIS RIBOSE-5-PHOSPHATE ISOMERASE, RPIB, RV2465C, IN COMPLEX WITH 4-PHOSPHO-D-ERYTHRONOHYDROXAMIC ACID.
Template:ABSTRACT PUBMED 15590681
About this Structure
2BES is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
Reference
Competitive inhibitors of Mycobacterium tuberculosis ribose-5-phosphate isomerase B reveal new information about the reaction mechanism., Roos AK, Burgos E, Ericsson DJ, Salmon L, Mowbray SL, J Biol Chem. 2005 Feb 25;280(8):6416-22. Epub 2004 Dec 7. PMID:15590681
Page seeded by OCA on Mon Jul 28 15:10:06 2008
