1nnr
From Proteopedia
(New page: 200px<br /><applet load="1nnr" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nnr, resolution 2.25Å" /> '''Crystal structure of...) |
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| - | [[Image:1nnr.gif|left|200px]]<br /><applet load="1nnr" size=" | + | [[Image:1nnr.gif|left|200px]]<br /><applet load="1nnr" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1nnr, resolution 2.25Å" /> | caption="1nnr, resolution 2.25Å" /> | ||
'''Crystal structure of a probable fosfomycin resistance protein (PA1129) from Pseudomonas aeruginosa with sulfate present in the active site'''<br /> | '''Crystal structure of a probable fosfomycin resistance protein (PA1129) from Pseudomonas aeruginosa with sulfate present in the active site'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Fosfomycin [(1R,2S)-epoxypropylphosphonic acid] is a simple phosphonate | + | Fosfomycin [(1R,2S)-epoxypropylphosphonic acid] is a simple phosphonate found to have antibacterial activity against both Gram-positive and Gram-negative microorganisms. Early resistance to the clinical use of the antibiotic was linked to a plasmid-encoded resistance protein, FosA, that catalyzes the addition of glutathione to the oxirane ring, rendering the antibiotic inactive. Subsequent studies led to the discovery of a genomically encoded homologue in the pathogen Pseudomonas aeruginosa. The proteins are Mn(II)-dependent enzymes where the metal is proposed to act as a Lewis acid stabilizing the negative charge that develops on the oxirane oxygen in the transition state. Several simple phosphonates, including the antiviral compound phosphonoformate (K(i) = 0.4 +/- 0.1 microM, K(d) approximately 0.2 microM), are shown to be inhibitors of FosA. The crystal structure of FosA from P. aeruginosa with phosphonoformate bound in the active site has been determined at 0.95 A resolution and reveals that the inhibitor forms a five-coordinate complex with the Mn(II) center with a geometry similar to that proposed for the transition state of the reaction. Binding studies show that phosphonoformate has a near-diffusion-controlled on rate (k(on) approximately 10(7)-10(8) M(-1) s(-1)) and an off rate (k(off) = 5 s(-1)) that is slower than that for fosfomycin (k(off) = 30 s(-1)). Taken together, these data suggest that the FosA-catalyzed reaction has a very early transition state and phosphonoformate acts as a minimal transition state analogue inhibitor. |
==About this Structure== | ==About this Structure== | ||
| - | 1NNR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa_pao1 Pseudomonas aeruginosa pao1] with MN and SO4 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glutathione_transferase Glutathione transferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.18 2.5.1.18] Full crystallographic information is available from [http:// | + | 1NNR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa_pao1 Pseudomonas aeruginosa pao1] with <scene name='pdbligand=MN:'>MN</scene> and <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glutathione_transferase Glutathione transferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.18 2.5.1.18] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NNR OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Pseudomonas aeruginosa pao1]] | [[Category: Pseudomonas aeruginosa pao1]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Armstrong, R | + | [[Category: Armstrong, R N.]] |
| - | [[Category: Newcomer, M | + | [[Category: Newcomer, M E.]] |
| - | [[Category: Pharris, R | + | [[Category: Pharris, R E.]] |
| - | [[Category: Rife, C | + | [[Category: Rife, C L.]] |
[[Category: MN]] | [[Category: MN]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
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[[Category: potassium binding loop]] | [[Category: potassium binding loop]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:08:05 2008'' |
Revision as of 12:08, 21 February 2008
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Crystal structure of a probable fosfomycin resistance protein (PA1129) from Pseudomonas aeruginosa with sulfate present in the active site
Overview
Fosfomycin [(1R,2S)-epoxypropylphosphonic acid] is a simple phosphonate found to have antibacterial activity against both Gram-positive and Gram-negative microorganisms. Early resistance to the clinical use of the antibiotic was linked to a plasmid-encoded resistance protein, FosA, that catalyzes the addition of glutathione to the oxirane ring, rendering the antibiotic inactive. Subsequent studies led to the discovery of a genomically encoded homologue in the pathogen Pseudomonas aeruginosa. The proteins are Mn(II)-dependent enzymes where the metal is proposed to act as a Lewis acid stabilizing the negative charge that develops on the oxirane oxygen in the transition state. Several simple phosphonates, including the antiviral compound phosphonoformate (K(i) = 0.4 +/- 0.1 microM, K(d) approximately 0.2 microM), are shown to be inhibitors of FosA. The crystal structure of FosA from P. aeruginosa with phosphonoformate bound in the active site has been determined at 0.95 A resolution and reveals that the inhibitor forms a five-coordinate complex with the Mn(II) center with a geometry similar to that proposed for the transition state of the reaction. Binding studies show that phosphonoformate has a near-diffusion-controlled on rate (k(on) approximately 10(7)-10(8) M(-1) s(-1)) and an off rate (k(off) = 5 s(-1)) that is slower than that for fosfomycin (k(off) = 30 s(-1)). Taken together, these data suggest that the FosA-catalyzed reaction has a very early transition state and phosphonoformate acts as a minimal transition state analogue inhibitor.
About this Structure
1NNR is a Single protein structure of sequence from Pseudomonas aeruginosa pao1 with and as ligands. Active as Glutathione transferase, with EC number 2.5.1.18 Full crystallographic information is available from OCA.
Reference
Phosphonoformate: a minimal transition state analogue inhibitor of the fosfomycin resistance protein, FosA., Rigsby RE, Rife CL, Fillgrove KL, Newcomer ME, Armstrong RN, Biochemistry. 2004 Nov 2;43(43):13666-73. PMID:15504029
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