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.


2aaj

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:2aaj.gif|left|200px]]
+
{{Seed}}
 +
[[Image:2aaj.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2aaj| PDB=2aaj | SCENE= }}
{{STRUCTURE_2aaj| PDB=2aaj | SCENE= }}
-
'''Crystal Structures of the Wild-type, Mutant-P1A and Inactivated Malonate Semialdehyde Decarboxylase: A Structural Basis for the Decarboxylase and Hydratase Activities'''
+
===Crystal Structures of the Wild-type, Mutant-P1A and Inactivated Malonate Semialdehyde Decarboxylase: A Structural Basis for the Decarboxylase and Hydratase Activities===
-
==Overview==
+
<!--
-
Malonate semialdehyde decarboxylase (MSAD) from Pseudomonas pavonaceae 170 is a tautomerase superfamily member that converts malonate semialdehyde to acetaldehyde by a mechanism utilizing Pro-1 and Arg-75. Pro-1 and Arg-75 have also been implicated in the hydratase activity of MSAD in which 2-oxo-3-pentynoate is processed to acetopyruvate. Crystal structures of MSAD (1.8 A resolution), the P1A mutant of MSAD (2.7 A resolution), and MSAD inactivated by 3-chloropropiolate (1.6 A resolution), a mechanism-based inhibitor activated by the hydratase activity of MSAD, have been determined. A comparison of the P1A-MSAD and MSAD structures reveals little geometric alteration, indicating that Pro-1 plays an important catalytic role but not a critical structural role. The structures of wild-type MSAD and MSAD covalently modified at Pro-1 by 3-oxopropanoate, the adduct resulting from the incubation of MSAD and 3-chloropropiolate, implicate Asp-37 as the residue that activates a water molecule for attack at C-3 of 3-chloropropiolate to initiate a Michael addition of water. The interactions of Arg-73 and Arg-75 with the C-1 carboxylate group of the adduct suggest these residues polarize the alpha,beta-unsaturated acid and facilitate the addition of water. On the basis of these structures, a mechanism for the inactivation of MSAD by 3-chloropropiolate can be formulated along with mechanisms for the decarboxylase and hydratase activities. The results also provide additional evidence supporting the hypothesis that MSAD and trans-3-chloroacrylic acid dehalogenase, a tautomerase superfamily member preceding MSAD in the trans-1,3-dichloropropene degradation pathway, diverged from a common ancestor but retained the key elements for the conjugate addition of water.
+
The line below this paragraph, {{ABSTRACT_PUBMED_16274229}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 16274229 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_16274229}}
==About this Structure==
==About this Structure==
Line 31: Line 35:
[[Category: Homotrimeric]]
[[Category: Homotrimeric]]
[[Category: Tautomerase superfamily]]
[[Category: Tautomerase superfamily]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 18:48:58 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 06:34:17 2008''

Revision as of 03:34, 29 July 2008

Template:STRUCTURE 2aaj

Crystal Structures of the Wild-type, Mutant-P1A and Inactivated Malonate Semialdehyde Decarboxylase: A Structural Basis for the Decarboxylase and Hydratase Activities

Template:ABSTRACT PUBMED 16274229

About this Structure

2AAJ is a Single protein structure of sequence from Pseudomonas pavonaceae. Full crystallographic information is available from OCA.

Reference

Crystal structures of the wild-type, P1A mutant, and inactivated malonate semialdehyde decarboxylase: a structural basis for the decarboxylase and hydratase activities., Almrud JJ, Poelarends GJ, Johnson WH Jr, Serrano H, Hackert ML, Whitman CP, Biochemistry. 2005 Nov 15;44(45):14818-27. PMID:16274229

Page seeded by OCA on Tue Jul 29 06:34:17 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools