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.


1y6f

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1y6f.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1y6f.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1y6f| PDB=1y6f | SCENE= }}
{{STRUCTURE_1y6f| PDB=1y6f | SCENE= }}
-
'''alpha-glucosyltransferase in complex with UDP-glucose and DNA containing an abasic site'''
+
===alpha-glucosyltransferase in complex with UDP-glucose and DNA containing an abasic site===
-
==Overview==
+
<!--
-
The Escherichia coli T4 bacteriophage uses two glycosyltransferases to glucosylate and thus protect its DNA: the retaining alpha-glucosyltransferase (AGT) and the inverting beta-glucosyltransferase (BGT). They glucosylate 5-hydroxymethyl cytosine (5-HMC) bases of duplex DNA using UDP-glucose as the sugar donor to form an alpha-glucosidic linkage and a beta-glucosidic linkage, respectively. Five structures of AGT have been determined: a binary complex with the UDP product and four ternary complexes with UDP or UDP-glucose and oligonucleotides containing an A:G, HMU:G (hydroxymethyl uracyl) or AP:G (apurinic/apyrimidinic) mismatch at the target base-pair. AGT adopts the GT-B fold, one of the two folds known for GTs. However, while the sugar donor binding mode is classical for a GT-B enzyme, the sugar acceptor binding mode is unexpected and breaks the established consensus: AGT is the first GT-B enzyme that predominantly binds both the sugar donor and acceptor to the C-terminal domain. Its active site pocket is highly similar to four retaining GT-B glycosyltransferases (trehalose-6-phosphate synthase, glycogen synthase, glycogen and maltodextrin phosphorylases) strongly suggesting a common evolutionary origin and catalytic mechanism for these enzymes. Structure-guided mutagenesis and kinetic analysis do not permit identification of a nucleophile residue responsible for a glycosyl-enzyme intermediate for the classical double displacement mechanism. Interestingly, the DNA structures reveal partially flipped-out bases. They provide evidence for a passive role of AGT in the base-flipping mechanism and for its specific recognition of the acceptor base.
+
The line below this paragraph, {{ABSTRACT_PUBMED_16081100}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 16081100 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_16081100}}
==About this Structure==
==About this Structure==
Line 27: Line 31:
[[Category: Sommer, N.]]
[[Category: Sommer, N.]]
[[Category: Transferase]]
[[Category: Transferase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 15:55:39 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Jul 27 23:08:13 2008''

Revision as of 20:08, 27 July 2008

Template:STRUCTURE 1y6f

alpha-glucosyltransferase in complex with UDP-glucose and DNA containing an abasic site

Template:ABSTRACT PUBMED 16081100

About this Structure

1Y6F is a Single protein structure of sequence from Enterobacteria phage t4. Full crystallographic information is available from OCA.

Reference

Structural evidence of a passive base-flipping mechanism for AGT, an unusual GT-B glycosyltransferase., Lariviere L, Sommer N, Morera S, J Mol Biol. 2005 Sep 9;352(1):139-50. PMID:16081100

Page seeded by OCA on Sun Jul 27 23:08:13 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools