2flt: Difference between revisions
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'''The X-ray structure of the cis-3-chloroacrylic acid dehalogenase cis-CaaD inactivated with (R)-Oxirane-2-carboxylate''' | {{Structure | ||
|PDB= 2flt |SIZE=350|CAPTION= <scene name='initialview01'>2flt</scene>, resolution 2.10Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=LAC:LACTIC ACID'>LAC</scene> | |||
|ACTIVITY= | |||
|GENE= | |||
}} | |||
'''The X-ray structure of the cis-3-chloroacrylic acid dehalogenase cis-CaaD inactivated with (R)-Oxirane-2-carboxylate''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
2FLT is a [ | 2FLT is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Coryneform_bacterium Coryneform bacterium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FLT OCA]. | ||
==Reference== | ==Reference== | ||
Crystal structures of native and inactivated cis-3-chloroacrylic acid dehalogenase. Structural basis for substrate specificity and inactivation by (R)-oxirane-2-carboxylate., de Jong RM, Bazzacco P, Poelarends GJ, Johnson WH Jr, Kim YJ, Burks EA, Serrano H, Thunnissen AM, Whitman CP, Dijkstra BW, J Biol Chem. 2007 Jan 26;282(4):2440-9. Epub 2006 Nov 22. PMID:[http:// | Crystal structures of native and inactivated cis-3-chloroacrylic acid dehalogenase. Structural basis for substrate specificity and inactivation by (R)-oxirane-2-carboxylate., de Jong RM, Bazzacco P, Poelarends GJ, Johnson WH Jr, Kim YJ, Burks EA, Serrano H, Thunnissen AM, Whitman CP, Dijkstra BW, J Biol Chem. 2007 Jan 26;282(4):2440-9. Epub 2006 Nov 22. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17121835 17121835] | ||
[[Category: Coryneform bacterium]] | [[Category: Coryneform bacterium]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: hydratase]] | [[Category: hydratase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 16:53:58 2008'' | ||
Revision as of 17:53, 20 March 2008
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
The X-ray structure of the cis-3-chloroacrylic acid dehalogenase cis-CaaD inactivated with (R)-Oxirane-2-carboxylate
OverviewOverview
The bacterial degradation pathways for the nematocide 1,3-dichloropropene rely on hydrolytic dehalogenation reactions catalyzed by cis- and trans-3-chloroacrylic acid dehalogenases (cis-CaaD and CaaD, respectively). X-ray crystal structures of native cis-CaaD and cis-CaaD inactivated by (R)-oxirane-2-carboxylate were elucidated. They locate four known catalytic residues (Pro-1, Arg-70, Arg-73, and Glu-114) and two previously unknown, potential catalytic residues (His-28 and Tyr-103'). The Y103F and H28A mutants of these latter two residues displayed reductions in cis-CaaD activity confirming their importance in catalysis. The structure of the inactivated enzyme shows covalent modification of the Pro-1 nitrogen atom by (R)-2-hydroxypropanoate at the C3 position. The interactions in the complex implicate Arg-70 or a water molecule bound to Arg-70 as the proton donor for the epoxide ring-opening reaction and Arg-73 and His-28 as primary binding contacts for the carboxylate group. This proposed binding mode places the (R)-enantiomer, but not the (S)-enantiomer, in position to covalently modify Pro-1. The absence of His-28 (or an equivalent) in CaaD could account for the fact that CaaD is not inactivated by either enantiomer. The cis-CaaD structures support a mechanism in which Glu-114 and Tyr-103' activate a water molecule for addition to C3 of the substrate and His-28, Arg-70, and Arg-73 interact with the C1 carboxylate group to assist in substrate binding and polarization. Pro-1 provides a proton at C2. The involvement of His-28 and Tyr-103' distinguishes the cis-CaaD mechanism from the otherwise parallel CaaD mechanism. The two mechanisms probably evolved independently as the result of an early gene duplication of a common ancestor.
About this StructureAbout this Structure
2FLT is a Single protein structure of sequence from Coryneform bacterium. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of native and inactivated cis-3-chloroacrylic acid dehalogenase. Structural basis for substrate specificity and inactivation by (R)-oxirane-2-carboxylate., de Jong RM, Bazzacco P, Poelarends GJ, Johnson WH Jr, Kim YJ, Burks EA, Serrano H, Thunnissen AM, Whitman CP, Dijkstra BW, J Biol Chem. 2007 Jan 26;282(4):2440-9. Epub 2006 Nov 22. PMID:17121835
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