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.


1axe

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1axe.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1axe.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1axe| PDB=1axe | SCENE= }}
{{STRUCTURE_1axe| PDB=1axe | SCENE= }}
-
'''CRYSTAL STRUCTURE OF THE ACTIVE-SITE MUTANT PHE93->TRP OF HORSE LIVER ALCOHOL DEHYDROGENASE IN COMPLEX WITH NAD AND INHIBITOR TRIFLUOROETHANOL'''
+
===CRYSTAL STRUCTURE OF THE ACTIVE-SITE MUTANT PHE93->TRP OF HORSE LIVER ALCOHOL DEHYDROGENASE IN COMPLEX WITH NAD AND INHIBITOR TRIFLUOROETHANOL===
-
==Overview==
+
<!--
-
We present evidence that the size of an active site side chain may modulate the degree of hydrogen tunneling in an enzyme-catalyzed reaction. Primary and secondary kH/kT and kD/kT kinetic isotope effects have been measured for the oxidation of benzyl alcohol catalyzed by horse liver alcohol dehydrogenase at 25 degrees C. As reported in earlier studies, the relationship between secondary kH/kT and kD/kT isotope effects provides a sensitive probe for deviations from classical behavior. In the present work, catalytic efficiency and the extent of hydrogen tunneling have been correlated for the alcohol dehydrogenase-catalyzed hydride transfer among a group of site-directed mutants at position 203. Val-203 interacts with the opposite face of the cofactor NAD+ from the alcohol substrate. The reduction in size of this residue is correlated with diminished tunneling and a two orders of magnitude decrease in catalytic efficiency. Comparison of the x-ray crystal structures of a ternary complex of a high-tunneling (Phe-93 --&gt; Trp) and a low-tunneling (Val-203 --&gt; Ala) mutant provides a structural basis for the observed effects, demonstrating an increase in the hydrogen transfer distance for the low-tunneling mutant. The Val-203 --&gt; Ala ternary complex crystal structure also shows a hyperclosed interdomain geometry relative to the wild-type and the Phe-93 --&gt; Trp mutant ternary complex structures. This demonstrates a flexibility in interdomain movement that could potentially narrow the distance between the donor and acceptor carbons in the native enzyme and may enhance the role of tunneling in the hydride transfer reaction.
+
The line below this paragraph, {{ABSTRACT_PUBMED_9371755}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 9371755 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_9371755}}
==About this Structure==
==About this Structure==
Line 27: Line 31:
[[Category: Goldstein, B M.]]
[[Category: Goldstein, B M.]]
[[Category: Alcohol dehydrogenase]]
[[Category: Alcohol dehydrogenase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 10:48:33 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 17:47:52 2008''

Revision as of 14:47, 30 June 2008

Image:1axe.png

Template:STRUCTURE 1axe

CRYSTAL STRUCTURE OF THE ACTIVE-SITE MUTANT PHE93->TRP OF HORSE LIVER ALCOHOL DEHYDROGENASE IN COMPLEX WITH NAD AND INHIBITOR TRIFLUOROETHANOL

Template:ABSTRACT PUBMED 9371755

About this Structure

1AXE is a Single protein structure of sequence from Equus caballus. Full crystallographic information is available from OCA.

Reference

A link between protein structure and enzyme catalyzed hydrogen tunneling., Bahnson BJ, Colby TD, Chin JK, Goldstein BM, Klinman JP, Proc Natl Acad Sci U S A. 1997 Nov 25;94(24):12797-802. PMID:9371755

Page seeded by OCA on Mon Jun 30 17:47:52 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

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