1v54

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1v54.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1v54.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1v54| PDB=1v54 | SCENE= }}
{{STRUCTURE_1v54| PDB=1v54 | SCENE= }}
-
'''Bovine heart cytochrome c oxidase at the fully oxidized state'''
+
===Bovine heart cytochrome c oxidase at the fully oxidized state===
-
==Overview==
+
<!--
-
Mitochondrial cytochrome c oxidase plays an essential role in aerobic cellular respiration, reducing dioxygen to water in a process coupled with the pumping of protons across the mitochondrial inner membrane. An aspartate residue, Asp-51, located near the enzyme surface, undergoes a redox-coupled x-ray structural change, which is suggestive of a role for this residue in redox-driven proton pumping. However, functional or mechanistic evidence for the involvement of this residue in proton pumping has not yet been obtained. We report that the Asp-51 --&gt; Asn mutation of the bovine enzyme abolishes its proton-pumping function without impairment of the dioxygen reduction activity. Improved x-ray structures (at 1.8/1.9-A resolution in the fully oxidized/reduced states) show that the net positive charge created upon oxidation of the low-spin heme of the enzyme drives the active proton transport from the interior of the mitochondria to Asp-51 across the enzyme via a water channel and a hydrogen-bond network, located in tandem, and that the enzyme reduction induces proton ejection from the aspartate to the mitochondrial exterior. A peptide bond in the hydrogen-bond network critically inhibits reverse proton transfer through the network. A redox-coupled change in the capacity of the water channel, induced by the hydroxyfarnesylethyl group of the low-spin heme, suggests that the channel functions as an effective proton-collecting region. Infrared results indicate that the conformation of Asp-51 is controlled only by the oxidation state of the low-spin heme. These results indicate that the low-spin heme drives the proton-pumping process.
+
The line below this paragraph, {{ABSTRACT_PUBMED_14673090}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 14673090 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_14673090}}
==About this Structure==
==About this Structure==
Line 36: Line 40:
[[Category: Yoshikawa, S.]]
[[Category: Yoshikawa, S.]]
[[Category: Oxidoreductase]]
[[Category: Oxidoreductase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 12:05:14 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 09:53:24 2008''

Revision as of 06:53, 29 July 2008

Template:STRUCTURE 1v54

Bovine heart cytochrome c oxidase at the fully oxidized state

Template:ABSTRACT PUBMED 14673090

About this Structure

1V54 is a Protein complex structure of sequences from Bos taurus. Full crystallographic information is available from OCA.

Reference

The low-spin heme of cytochrome c oxidase as the driving element of the proton-pumping process., Tsukihara T, Shimokata K, Katayama Y, Shimada H, Muramoto K, Aoyama H, Mochizuki M, Shinzawa-Itoh K, Yamashita E, Yao M, Ishimura Y, Yoshikawa S, Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15304-9. Epub 2003 Dec 12. PMID:14673090

Page seeded by OCA on Tue Jul 29 09:53:24 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools