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.


1lrj

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1lrj.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1lrj.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1lrj| PDB=1lrj | SCENE= }}
{{STRUCTURE_1lrj| PDB=1lrj | SCENE= }}
-
'''Crystal Structure of E. coli UDP-Galactose 4-Epimerase Complexed with UDP-N-Acetylglucosamine'''
+
===Crystal Structure of E. coli UDP-Galactose 4-Epimerase Complexed with UDP-N-Acetylglucosamine===
-
==Overview==
+
<!--
-
UDP-galactose 4-epimerase catalyzes the interconversion of UDP-Gal and UDP-Glc during normal galactose metabolism. The mammalian form of the enzyme, unlike its Escherichia coli counterpart, can also interconvert UDP-GalNAc and UDP-GlcNAc. One key feature of the epimerase reaction mechanism is the rotation of a 4-ketopyranose intermediate in the active site. By comparing the high resolution x-ray structures of both the bacterial and human forms of the enzyme, it was previously postulated that the additional activity in the human epimerase was due to replacement of the structural equivalent of Tyr-299 in the E. coli enzyme with a cysteine residue, thereby leading to a larger active site volume. To test this hypothesis, the Y299C mutant form of the E. coli enzyme was prepared and its three-dimensional structure solved as described here. Additionally, the Y299C mutant protein was assayed for activity against both UDP-Gal and UDP-GalNAc. These studies have revealed that, indeed, this simple mutation did confer UDP-GalNAc/UDP-GlcNAc converting activity to the bacterial enzyme with minimal changes in its three-dimensional structure. Specifically, although the Y299C mutation in the bacterial enzyme resulted in a loss of epimerase activity with regard to UDP-Gal by almost 5-fold, it resulted in a gain of activity against UDP-GalNAc by more than 230-fold.
+
The line below this paragraph, {{ABSTRACT_PUBMED_12019271}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 12019271 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_12019271}}
==About this Structure==
==About this Structure==
Line 30: Line 34:
[[Category: Galactosemia]]
[[Category: Galactosemia]]
[[Category: Short chain dehydrogenase]]
[[Category: Short chain dehydrogenase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 00:12:47 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 2 21:53:11 2008''

Revision as of 18:53, 2 July 2008

Image:1lrj.png

Template:STRUCTURE 1lrj

Crystal Structure of E. coli UDP-Galactose 4-Epimerase Complexed with UDP-N-Acetylglucosamine

Template:ABSTRACT PUBMED 12019271

About this Structure

1LRJ is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

Reference

Structural analysis of the Y299C mutant of Escherichia coli UDP-galactose 4-epimerase. Teaching an old dog new tricks., Thoden JB, Henderson JM, Fridovich-Keil JL, Holden HM, J Biol Chem. 2002 Jul 26;277(30):27528-34. Epub 2002 May 17. PMID:12019271

Page seeded by OCA on Wed Jul 2 21:53:11 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

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