1iz7
From Proteopedia
(New page: 200px<br /><applet load="1iz7" size="450" color="white" frame="true" align="right" spinBox="true" caption="1iz7, resolution 1.58Å" /> '''RE-REFINEMENT OF THE...) |
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| - | [[Image:1iz7.jpg|left|200px]]<br /><applet load="1iz7" size=" | + | [[Image:1iz7.jpg|left|200px]]<br /><applet load="1iz7" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1iz7, resolution 1.58Å" /> | caption="1iz7, resolution 1.58Å" /> | ||
'''RE-REFINEMENT OF THE STRUCTURE OF HYDROLYTIC HALOALKANE DEHALOGENASE LINB FROM SPHINGOMONAS PAUCIMOBILIS UT26 AT 1.6 A RESOLUTION'''<br /> | '''RE-REFINEMENT OF THE STRUCTURE OF HYDROLYTIC HALOALKANE DEHALOGENASE LINB FROM SPHINGOMONAS PAUCIMOBILIS UT26 AT 1.6 A RESOLUTION'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The haloalkane dehalogenases are detoxifying enzymes that convert a broad | + | The haloalkane dehalogenases are detoxifying enzymes that convert a broad range of halogenated substrates to the corresponding alcohols. Complete crystal structures of haloalkane dehalogenase from Sphingomonas paucimobilis UT26 (LinB), and complexes of LinB with 1,2-propanediol/1-bromopropane-2-ol and 2-bromo-2-propene-1-ol, products of debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, were determined from 1.8 A resolution X-ray diffraction data. Published structures of native LinB and its complex with 1,3-propanediol [Marek et al. (2000) Biochemistry 39, 14082-14086] were reexamined. The full and partial debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, conformed to the observed general trend that the sp(3)-hybridized carbon is the predominant electrophilic site for the S(N)2 bimolecular nucleophilic substitution in dehalogenation reaction. The 2-bromo-2-propene-1-ol product of 2,3-dibromopropene dehalogenation in crystal was positively identified by the gas chromatography-mass spectroscopy (GC-MS) technique. The 1,2-propanediol and 1-bromopropane-2-ol products of 1,2-dibromopropane dehalogenation in crystal were also supported by the GC-MS identification. Comparison of native LinB with its complexes showed high flexibility of residues 136-157, in particular, Asp146 and Glu147, from the cap domain helices alpha(4) and alpha(5)('). Those residues were shifted mainly in direction toward the ligand molecules in the complex structures. It seems the cap domain moves nearer to the core squeezing substrate into the active center closer to the catalytic triad. This also leads to slight contraction of the whole complex structures. The flexibility detected by crystallographic analysis is in remarkable agreement with flexibility observed by molecular dynamic simulations. |
==About this Structure== | ==About this Structure== | ||
| - | 1IZ7 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sphingomonas_paucimobilis Sphingomonas paucimobilis] with CL and CA as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1IZ7 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sphingomonas_paucimobilis Sphingomonas paucimobilis] with <scene name='pdbligand=CL:'>CL</scene> and <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IZ7 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Sphingomonas paucimobilis]] | [[Category: Sphingomonas paucimobilis]] | ||
| - | [[Category: Streltsov, V | + | [[Category: Streltsov, V A.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: CL]] | [[Category: CL]] | ||
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[[Category: lindane]] | [[Category: lindane]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:17:19 2008'' |
Revision as of 11:17, 21 February 2008
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RE-REFINEMENT OF THE STRUCTURE OF HYDROLYTIC HALOALKANE DEHALOGENASE LINB FROM SPHINGOMONAS PAUCIMOBILIS UT26 AT 1.6 A RESOLUTION
Overview
The haloalkane dehalogenases are detoxifying enzymes that convert a broad range of halogenated substrates to the corresponding alcohols. Complete crystal structures of haloalkane dehalogenase from Sphingomonas paucimobilis UT26 (LinB), and complexes of LinB with 1,2-propanediol/1-bromopropane-2-ol and 2-bromo-2-propene-1-ol, products of debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, were determined from 1.8 A resolution X-ray diffraction data. Published structures of native LinB and its complex with 1,3-propanediol [Marek et al. (2000) Biochemistry 39, 14082-14086] were reexamined. The full and partial debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, conformed to the observed general trend that the sp(3)-hybridized carbon is the predominant electrophilic site for the S(N)2 bimolecular nucleophilic substitution in dehalogenation reaction. The 2-bromo-2-propene-1-ol product of 2,3-dibromopropene dehalogenation in crystal was positively identified by the gas chromatography-mass spectroscopy (GC-MS) technique. The 1,2-propanediol and 1-bromopropane-2-ol products of 1,2-dibromopropane dehalogenation in crystal were also supported by the GC-MS identification. Comparison of native LinB with its complexes showed high flexibility of residues 136-157, in particular, Asp146 and Glu147, from the cap domain helices alpha(4) and alpha(5)('). Those residues were shifted mainly in direction toward the ligand molecules in the complex structures. It seems the cap domain moves nearer to the core squeezing substrate into the active center closer to the catalytic triad. This also leads to slight contraction of the whole complex structures. The flexibility detected by crystallographic analysis is in remarkable agreement with flexibility observed by molecular dynamic simulations.
About this Structure
1IZ7 is a Single protein structure of sequence from Sphingomonas paucimobilis with and as ligands. Full crystallographic information is available from OCA.
Reference
Haloalkane dehalogenase LinB from Sphingomonas paucimobilis UT26: X-ray crystallographic studies of dehalogenation of brominated substrates., Streltsov VA, Prokop Z, Damborsky J, Nagata Y, Oakley A, Wilce MC, Biochemistry. 2003 Sep 2;42(34):10104-12. PMID:12939138
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