1bgn
From Proteopedia
(New page: 200px<br /><applet load="1bgn" size="450" color="white" frame="true" align="right" spinBox="true" caption="1bgn, resolution 2.0Å" /> '''P-HYDROXYBENZOATE HYD...) |
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- | [[Image:1bgn.gif|left|200px]]<br /><applet load="1bgn" size=" | + | [[Image:1bgn.gif|left|200px]]<br /><applet load="1bgn" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1bgn, resolution 2.0Å" /> | caption="1bgn, resolution 2.0Å" /> | ||
'''P-HYDROXYBENZOATE HYDROXYLASE (PHBH) MUTANT WITH CYS 116 REPLACED BY SER (C116S) AND ARG 269 REPLACED BY THR (R269T), IN COMPLEX WITH FAD AND 4-HYDROXYBENZOIC ACID'''<br /> | '''P-HYDROXYBENZOATE HYDROXYLASE (PHBH) MUTANT WITH CYS 116 REPLACED BY SER (C116S) AND ARG 269 REPLACED BY THR (R269T), IN COMPLEX WITH FAD AND 4-HYDROXYBENZOIC ACID'''<br /> | ||
==Overview== | ==Overview== | ||
- | The conserved residues His-162 and Arg-269 of the flavoprotein | + | The conserved residues His-162 and Arg-269 of the flavoprotein p-hydroxybenzoate hydroxylase (EC 1.14.13.2) are located at the entrance of the interdomain cleft that leads toward the active site. To study their putative role in NADPH binding, His-162 and Arg-269 were selectively changed by site-specific mutagenesis. The catalytic properties of H162R, H162Y, and R269K were similar to the wild-type enzyme. However, less conservative His-162 and Arg-269 replacements strongly impaired NADPH binding without affecting the conformation of the flavin ring and the efficiency of substrate hydroxylation. The crystal structures of H162R and R269T in complex with 4-hydroxybenzoate were solved at 3.0 and 2.0 A resolution, respectively. Both structures are virtually indistinguishable from the wild-type enzyme-substrate complex except for the substituted side chains. In contrast to wild-type p-hydroxybenzoate hydroxylase, H162R is not inactivated by diethyl pyrocarbonate. NADPH protects wild-type p-hydroxybenzoate hydroxylase from diethylpyrocarbonate inactivation, suggesting that His-162 is involved in NADPH binding. Based on these results and GRID calculations we propose that the side chains of His-162 and Arg-269 interact with the pyrophosphate moiety of NADPH. An interdomain binding mode for NADPH is proposed which takes a novel sequence motif (Eppink, M. H. M., Schreuder, H. A., and van Berkel, W. J. H. (1997) Protein Sci. 6, 2454-2458) into account. |
==About this Structure== | ==About this Structure== | ||
- | 1BGN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_fluorescens Pseudomonas fluorescens] with FAD and PHB as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/4-hydroxybenzoate_3-monooxygenase 4-hydroxybenzoate 3-monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.13.2 1.14.13.2] Full crystallographic information is available from [http:// | + | 1BGN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_fluorescens Pseudomonas fluorescens] with <scene name='pdbligand=FAD:'>FAD</scene> and <scene name='pdbligand=PHB:'>PHB</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/4-hydroxybenzoate_3-monooxygenase 4-hydroxybenzoate 3-monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.13.2 1.14.13.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BGN OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Pseudomonas fluorescens]] | [[Category: Pseudomonas fluorescens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
- | [[Category: Berkel, W | + | [[Category: Berkel, W J.H Van.]] |
- | [[Category: Eppink, M | + | [[Category: Eppink, M H.M.]] |
- | [[Category: Schreuder, H | + | [[Category: Schreuder, H A.]] |
[[Category: FAD]] | [[Category: FAD]] | ||
[[Category: PHB]] | [[Category: PHB]] | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:55:05 2008'' |
Revision as of 09:55, 21 February 2008
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P-HYDROXYBENZOATE HYDROXYLASE (PHBH) MUTANT WITH CYS 116 REPLACED BY SER (C116S) AND ARG 269 REPLACED BY THR (R269T), IN COMPLEX WITH FAD AND 4-HYDROXYBENZOIC ACID
Overview
The conserved residues His-162 and Arg-269 of the flavoprotein p-hydroxybenzoate hydroxylase (EC 1.14.13.2) are located at the entrance of the interdomain cleft that leads toward the active site. To study their putative role in NADPH binding, His-162 and Arg-269 were selectively changed by site-specific mutagenesis. The catalytic properties of H162R, H162Y, and R269K were similar to the wild-type enzyme. However, less conservative His-162 and Arg-269 replacements strongly impaired NADPH binding without affecting the conformation of the flavin ring and the efficiency of substrate hydroxylation. The crystal structures of H162R and R269T in complex with 4-hydroxybenzoate were solved at 3.0 and 2.0 A resolution, respectively. Both structures are virtually indistinguishable from the wild-type enzyme-substrate complex except for the substituted side chains. In contrast to wild-type p-hydroxybenzoate hydroxylase, H162R is not inactivated by diethyl pyrocarbonate. NADPH protects wild-type p-hydroxybenzoate hydroxylase from diethylpyrocarbonate inactivation, suggesting that His-162 is involved in NADPH binding. Based on these results and GRID calculations we propose that the side chains of His-162 and Arg-269 interact with the pyrophosphate moiety of NADPH. An interdomain binding mode for NADPH is proposed which takes a novel sequence motif (Eppink, M. H. M., Schreuder, H. A., and van Berkel, W. J. H. (1997) Protein Sci. 6, 2454-2458) into account.
About this Structure
1BGN is a Single protein structure of sequence from Pseudomonas fluorescens with and as ligands. Active as 4-hydroxybenzoate 3-monooxygenase, with EC number 1.14.13.2 Full crystallographic information is available from OCA.
Reference
Interdomain binding of NADPH in p-hydroxybenzoate hydroxylase as suggested by kinetic, crystallographic and modeling studies of histidine 162 and arginine 269 variants., Eppink MH, Schreuder HA, van Berkel WJ, J Biol Chem. 1998 Aug 14;273(33):21031-9. PMID:9694855
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