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.


3bza

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:3bza.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:3bza.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_3bza| PDB=3bza | SCENE= }}
{{STRUCTURE_3bza| PDB=3bza | SCENE= }}
-
'''Structure of Mn-substituted Homoprotocatechuate 2,3-Dioxygenase from B.fuscum at 1.7 Ang resolution'''
+
===Structure of Mn-substituted Homoprotocatechuate 2,3-Dioxygenase from B.fuscum at 1.7 Ang resolution===
-
==Overview==
+
<!--
-
Biological O(2) activation often occurs after binding to a reduced metal [e.g., M(II)] in an enzyme active site. Subsequent M(II)-to-O(2) electron transfer results in a reactive M(III)-superoxo species. For the extradiol aromatic ring-cleaving dioxygenases, we have proposed a different model where an electron is transferred from substrate to O(2) via the M(II) center to which they are both bound, thereby obviating the need for an integral change in metal redox state. This model is tested by using homoprotocatechuate 2,3-dioxygenases from Brevibacterium fuscum (Fe-HPCD) and Arthrobacter globiformis (Mn-MndD) that share high sequence identity and very similar structures. Despite these similarities, Fe-HPCD binds Fe(II) whereas Mn-MndD incorporates Mn(II). Methods are described to incorporate the nonphysiological metal into each enzyme (Mn-HPCD and Fe-MndD). The x-ray crystal structure of Mn-HPCD at 1.7 A is found to be indistinguishable from that of Fe-HPCD, while EPR studies show that the Mn(II) sites of Mn-MndD and Mn-HPCD, and the Fe(II) sites of the NO complexes of Fe-HPCD and Fe-MndD, are very similar. The uniform metal site structures of these enzymes suggest that extradiol dioxygenases cannot differentially compensate for the 0.7-V gap in the redox potentials of free iron and manganese. Nonetheless, all four enzymes exhibit nearly the same K(M) and V(max) values. These enzymes constitute an unusual pair of metallo-oxygenases that remain fully active after a metal swap, implicating a different way by which metals are used to promote oxygen activation without an integral change in metal redox state.
+
The line below this paragraph, {{ABSTRACT_PUBMED_18492808}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 18492808 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_18492808}}
==About this Structure==
==About this Structure==
Line 31: Line 35:
[[Category: Oxidoreductase]]
[[Category: Oxidoreductase]]
[[Category: Oxygenase]]
[[Category: Oxygenase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jun 11 10:57:44 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 12:31:32 2008''

Revision as of 09:31, 29 July 2008

Image:3bza.png

Template:STRUCTURE 3bza

Structure of Mn-substituted Homoprotocatechuate 2,3-Dioxygenase from B.fuscum at 1.7 Ang resolution

Template:ABSTRACT PUBMED 18492808

About this Structure

3BZA is a Single protein structure of sequence from Brevibacterium fuscum. Full crystallographic information is available from OCA.

Reference

Swapping metals in Fe- and Mn-dependent dioxygenases: evidence for oxygen activation without a change in metal redox state., Emerson JP, Kovaleva EG, Farquhar ER, Lipscomb JD, Que L Jr, Proc Natl Acad Sci U S A. 2008 May 27;105(21):7347-52. Epub 2008 May 20. PMID:18492808

Page seeded by OCA on Tue Jul 29 12:31:32 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/3bza"
Personal tools