2aag
From Proteopedia
| Line 7: | Line 7: | ||
|ACTIVITY= | |ACTIVITY= | ||
|GENE= orf130 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=47881 Pseudomonas pavonaceae]) | |GENE= orf130 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=47881 Pseudomonas pavonaceae]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[2aaj|2AAJ]], [[2aal|2AAL]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2aag FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aag OCA], [http://www.ebi.ac.uk/pdbsum/2aag PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2aag RCSB]</span> | ||
}} | }} | ||
| Line 28: | Line 31: | ||
[[Category: Serrano, H.]] | [[Category: Serrano, H.]] | ||
[[Category: Whitman, C P.]] | [[Category: Whitman, C P.]] | ||
| - | [[Category: | + | [[Category: beta-alpha-beta]] |
| + | [[Category: homotrimeric]] | ||
| + | [[Category: tautomerase superfamily]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:50:06 2008'' |
Revision as of 22:50, 30 March 2008
| |||||||
| , resolution 1.85Å | |||||||
|---|---|---|---|---|---|---|---|
| Gene: | orf130 (Pseudomonas pavonaceae) | ||||||
| Related: | 2AAJ, 2AAL
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
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.
About this Structure
2AAG 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 Mon Mar 31 01:50:06 2008
