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.


2nli

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:2nli.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:2nli.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2nli| PDB=2nli | SCENE= }}
{{STRUCTURE_2nli| PDB=2nli | SCENE= }}
-
'''Crystal Structure of the complex between L-lactate oxidase and a substrate analogue at 1.59 angstrom resolution'''
+
===Crystal Structure of the complex between L-lactate oxidase and a substrate analogue at 1.59 angstrom resolution===
-
==Overview==
+
<!--
-
L-Lactate oxidase (LOX) belongs to a family of flavin mononucleotide (FMN)-dependent alpha-hydroxy acid-oxidizing enzymes. Previously, the crystal structure of LOX (pH 8.0) from Aerococcus viridans was solved, revealing that the active site residues are located around the FMN. Here, we solved the crystal structures of the same enzyme at pH 4.5 and its complex with d-lactate at pH 4.5, in an attempt to analyze the intermediate steps. In the complex structure, the D-lactate resides in the substrate-binding site, but interestingly, an active site base, His265, flips far away from the D-lactate, as compared with its conformation in the unbound state at pH 8.0. This movement probably results from the protonation of His265 during the crystallization at pH 4.5, because the same flip is observed in the structure of the unbound state at pH 4.5. Thus, the present structure appears to mimic an intermediate after His265 abstracts a proton from the substrate. The flip of His265 triggers a large structural rearrangement, creating a new hydrogen bonding network between His265-Asp174-Lys221 and, furthermore, brings molecular oxygen in between D-lactate and His265. This mimic of the ternary complex intermediate enzyme-substrate-O(2) could explain the reductive half-reaction mechanism to release pyruvate through hydride transfer. In the mechanism of the subsequent oxidative half-reaction, His265 flips back, pushing molecular oxygen into the substrate-binding site as the second substrate, and the reverse reaction takes place to produce hydrogen peroxide. During the reaction, the flip-flop action of His265 has a dual role as an active base/acid to define the major chemical steps. Our proposed reaction mechanism appears to be a common mechanistic strategy for this family of enzymes.
+
The line below this paragraph, {{ABSTRACT_PUBMED_18367206}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 18367206 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_18367206}}
==About this Structure==
==About this Structure==
Line 38: Line 42:
[[Category: L-lactate oxidase]]
[[Category: L-lactate oxidase]]
[[Category: Oxidoreductase]]
[[Category: Oxidoreductase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Apr 24 09:25:02 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 01:48:21 2008''

Revision as of 22:48, 28 July 2008

Image:2nli.png

Template:STRUCTURE 2nli

Crystal Structure of the complex between L-lactate oxidase and a substrate analogue at 1.59 angstrom resolution

Template:ABSTRACT PUBMED 18367206

About this Structure

2NLI is a Single protein structure of sequence from Aerococcus viridans. Full crystallographic information is available from OCA.

Reference

X-ray structures of Aerococcus viridans lactate oxidase and its complex with D-lactate at pH 4.5 show an alpha-hydroxyacid oxidation mechanism., Furuichi M, Suzuki N, Dhakshnamoorhty B, Minagawa H, Yamagishi R, Watanabe Y, Goto Y, Kaneko H, Yoshida Y, Yagi H, Waga I, Kumar PK, Mizuno H, J Mol Biol. 2008 Apr 25;378(2):436-46. Epub 2008 Mar 3. PMID:18367206

Page seeded by OCA on Tue Jul 29 01:48:21 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

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