1gpu

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1gpu.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1gpu.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1gpu| PDB=1gpu | SCENE= }}
{{STRUCTURE_1gpu| PDB=1gpu | SCENE= }}
-
'''TRANSKETOLASE COMPLEX WITH REACTION INTERMEDIATE'''
+
===TRANSKETOLASE COMPLEX WITH REACTION INTERMEDIATE===
-
==Overview==
+
<!--
-
Kinetic and spectroscopic data indicated that addition of the donor substrate hydroxypyruvate to the thiamin diphosphate (ThDP)-dependent enzyme transketolase (TK) led to the accumulation of the alpha-carbanion/enamine of (alpha,beta-dihydroxyethyl) ThDP, the key reaction intermediate in enzymatic thiamin catalysis. The three-dimensional structure of this intermediate trapped in the active site of yeast TK was determined to 1.9-A resolution by using cryocrystallography. The electron density suggests a planar alpha-carbanion/enamine intermediate having the E-configuration. The reaction intermediate is firmly held in place through direct hydrogen bonds to His-103 and His-481 and an indirect hydrogen bond via a water molecule to His-69. The 4-NH(2) group of the amino-pyrimidine ring of ThDP is within 3 A distance to the alpha-hydroxy oxygen atom of the dihydroxyethyl moiety but at an angle unfavorable for a strong hydrogen bond. No structural changes occur in TK on formation of the reaction intermediate, suggesting that the active site is poised for catalysis and conformational changes during the enzyme reaction are not very likely. The intermediate is present with high occupancy in both active sites, arguing against previous proposals of half-of-the-sites reactivity in yeast TK.
+
The line below this paragraph, {{ABSTRACT_PUBMED_11773632}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 11773632 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_11773632}}
==About this Structure==
==About this Structure==
Line 28: Line 32:
[[Category: Schneider, G.]]
[[Category: Schneider, G.]]
[[Category: Thorell, S.]]
[[Category: Thorell, S.]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 17:52:13 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 1 05:42:52 2008''

Revision as of 02:43, 1 July 2008

Image:1gpu.png

Template:STRUCTURE 1gpu

TRANSKETOLASE COMPLEX WITH REACTION INTERMEDIATE

Template:ABSTRACT PUBMED 11773632

About this Structure

1GPU is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.

Reference

Snapshot of a key intermediate in enzymatic thiamin catalysis: crystal structure of the alpha-carbanion of (alpha,beta-dihydroxyethyl)-thiamin diphosphate in the active site of transketolase from Saccharomyces cerevisiae., Fiedler E, Thorell S, Sandalova T, Golbik R, Konig S, Schneider G, Proc Natl Acad Sci U S A. 2002 Jan 22;99(2):591-5. Epub 2002 Jan 2. PMID:11773632

Page seeded by OCA on Tue Jul 1 05:42:52 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1gpu"
Personal tools