This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


2ou4

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:2ou4.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:2ou4.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2ou4| PDB=2ou4 | SCENE= }}
{{STRUCTURE_2ou4| PDB=2ou4 | SCENE= }}
-
'''Crystal structure of D-tagatose 3-epimerase from Pseudomonas cichorii'''
+
===Crystal structure of D-tagatose 3-epimerase from Pseudomonas cichorii===
-
==Overview==
+
<!--
-
Pseudomonas cichoriiid-tagatose 3-epimerase (P. cichoriid-TE) can efficiently catalyze the epimerization of not only d-tagatose to d-sorbose, but also d-fructose to d-psicose, and is used for the production of d-psicose from d-fructose. The crystal structures of P. cichoriid-TE alone and in complexes with d-tagatose and d-fructose were determined at resolutions of 1.79, 2.28, and 2.06 A, respectively. A subunit of P. cichoriid-TE adopts a (beta/alpha)(8) barrel structure, and a metal ion (Mn(2+)) found in the active site is coordinated by Glu152, Asp185, His211, and Glu246 at the end of the beta-barrel. P. cichoriid-TE forms a stable dimer to give a favorable accessible surface for substrate binding on the front side of the dimer. The simulated omit map indicates that O2 and O3 of d-tagatose and/or d-fructose coordinate Mn(2+), and that C3-O3 is located between carboxyl groups of Glu152 and Glu246, supporting the previously proposed mechanism of deprotonation/protonation at C3 by two Glu residues. Although the electron density is poor at the 4-, 5-, and 6-positions of the substrates, substrate-enzyme interactions can be deduced from the significant electron density at O6. The O6 possibly interacts with Cys66 via hydrogen bonding, whereas O4 and O5 in d-tagatose and O4 in d-fructose do not undergo hydrogen bonding to the enzyme and are in a hydrophobic environment created by Phe7, Trp15, Trp113, and Phe248. Due to the lack of specific interactions between the enzyme and its substrates at the 4- and 5-positions, P. cichoriid-TE loosely recognizes substrates in this region, allowing it to efficiently catalyze the epimerization of d-tagatose and d-fructose (C4 epimer of d-tagatose) as well. Furthermore, a C3-O3 proton-exchange mechanism for P. cichoriid-TE is suggested by X-ray structural analysis, providing a clear explanation for the regulation of the ionization state of Glu152 and Glu246.
+
The line below this paragraph, {{ABSTRACT_PUBMED_17936787}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 17936787 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_17936787}}
==About this Structure==
==About this Structure==
Line 30: Line 34:
[[Category: Beta/alpha barrel]]
[[Category: Beta/alpha barrel]]
[[Category: Isomerase]]
[[Category: Isomerase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 11:39:28 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 09:22:15 2008''

Revision as of 06:22, 28 July 2008

Image:2ou4.png

Template:STRUCTURE 2ou4

Crystal structure of D-tagatose 3-epimerase from Pseudomonas cichorii

Template:ABSTRACT PUBMED 17936787

About this Structure

2OU4 is a Single protein structure of sequence from Pseudomonas cichorii. Full crystallographic information is available from OCA.

Reference

Crystal structures of D-tagatose 3-epimerase from Pseudomonas cichorii and its complexes with D-tagatose and D-fructose., Yoshida H, Yamada M, Nishitani T, Takada G, Izumori K, Kamitori S, J Mol Biol. 2007 Nov 23;374(2):443-53. Epub 2007 Sep 19. PMID:17936787

Page seeded by OCA on Mon Jul 28 09:22:15 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2ou4"
Personal tools