2cib
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Sterol 14alpha-demethylase (CYP51), a major checkpoint in membrane sterol | + | Sterol 14alpha-demethylase (CYP51), a major checkpoint in membrane sterol biosynthesis, is a key target for fungal antibiotic therapy. We sought small organic molecules for lead candidate CYP51 inhibitors. The changes in CYP51 spectral properties following ligand binding make CYP51 a convenient target for high-throughput screening technologies. These changes are characteristic of either substrate binding (type I) or inhibitor binding (type II) in the active site. We screened a library of 20,000 organic molecules against Mycobacterium tuberculosis CYP51 (CYP51(Mt)), examined the top type I and type II binding hits for their inhibitory effects on M. tuberculosis in broth culture, and analyzed them spectrally for their ability to discriminate between CYP51(Mt) and two reference M. tuberculosis CYP proteins, CYP130 and CYP125. We determined the binding mode for one of the top type II hits, alpha-ethyl-N-4-pyridinyl-benzeneacetamide (EPBA), by solving the X-ray structure of the CYP51(Mt)-EPBA complex to a resolution of 1.53 A. EPBA binds coordinately to the heme iron in the CYP51(Mt) active site through a lone pair of nitrogen electrons and also through hydrogen bonds with residues H259 and Y76, which are invariable in the CYP51 family, and hydrophobic interactions in a phylum- and/or substrate-specific cavity of CYP51. We also identified a second compound with structural and binding properties similar to those of EPBA, 2-(benzo[d]-2,1,3-thiadiazole-4-sulfonyl)-2-amino-2-phenyl-N-(pyridinyl-4) -acetamide (BSPPA). The congruence between the geometries of EPBA and BSPPA and the CYP51 binding site singles out EPBA and BSPPA as lead candidate CYP51 inhibitors with optimization potential for efficient discrimination between host and pathogen enzymes. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | Small | + | Small-molecule scaffolds for CYP51 inhibitors identified by high-throughput screening and defined by X-ray crystallography., Podust LM, von Kries JP, Eddine AN, Kim Y, Yermalitskaya LV, Kuehne R, Ouellet H, Warrier T, Altekoster M, Lee JS, Rademann J, Oschkinat H, Kaufmann SH, Waterman MR, Antimicrob Agents Chemother. 2007 Nov;51(11):3915-23. Epub 2007 Sep 10. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17846131 17846131] |
[[Category: Mycobacterium tuberculosis]] | [[Category: Mycobacterium tuberculosis]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Sterol 14-demethylase]] | [[Category: Sterol 14-demethylase]] | ||
[[Category: Kim, Y.]] | [[Category: Kim, Y.]] | ||
| - | [[Category: Kries, J | + | [[Category: Kries, J P.Von.]] |
| - | [[Category: Podust, L | + | [[Category: Podust, L M.]] |
| - | [[Category: Waterman, M | + | [[Category: Waterman, M R.]] |
| - | [[Category: Yermalitskaya, L | + | [[Category: Yermalitskaya, L V.]] |
[[Category: CM6]] | [[Category: CM6]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: sterol biosynthesis]] | [[Category: sterol biosynthesis]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:48:56 2008'' |
Revision as of 14:48, 21 February 2008
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HIGH THROUGHPUT SCREENING AND X-RAY CRYSTALLOGRAPHY ASSISTED EVALUATION OF SMALL MOLECULE SCAFFOLDS FOR CYP51 INHIBITORS
Overview
Sterol 14alpha-demethylase (CYP51), a major checkpoint in membrane sterol biosynthesis, is a key target for fungal antibiotic therapy. We sought small organic molecules for lead candidate CYP51 inhibitors. The changes in CYP51 spectral properties following ligand binding make CYP51 a convenient target for high-throughput screening technologies. These changes are characteristic of either substrate binding (type I) or inhibitor binding (type II) in the active site. We screened a library of 20,000 organic molecules against Mycobacterium tuberculosis CYP51 (CYP51(Mt)), examined the top type I and type II binding hits for their inhibitory effects on M. tuberculosis in broth culture, and analyzed them spectrally for their ability to discriminate between CYP51(Mt) and two reference M. tuberculosis CYP proteins, CYP130 and CYP125. We determined the binding mode for one of the top type II hits, alpha-ethyl-N-4-pyridinyl-benzeneacetamide (EPBA), by solving the X-ray structure of the CYP51(Mt)-EPBA complex to a resolution of 1.53 A. EPBA binds coordinately to the heme iron in the CYP51(Mt) active site through a lone pair of nitrogen electrons and also through hydrogen bonds with residues H259 and Y76, which are invariable in the CYP51 family, and hydrophobic interactions in a phylum- and/or substrate-specific cavity of CYP51. We also identified a second compound with structural and binding properties similar to those of EPBA, 2-(benzo[d]-2,1,3-thiadiazole-4-sulfonyl)-2-amino-2-phenyl-N-(pyridinyl-4) -acetamide (BSPPA). The congruence between the geometries of EPBA and BSPPA and the CYP51 binding site singles out EPBA and BSPPA as lead candidate CYP51 inhibitors with optimization potential for efficient discrimination between host and pathogen enzymes.
About this Structure
2CIB is a Single protein structure of sequence from Mycobacterium tuberculosis with and as ligands. Active as Sterol 14-demethylase, with EC number 1.14.13.70 Known structural/functional Sites: and . Full crystallographic information is available from OCA.
Reference
Small-molecule scaffolds for CYP51 inhibitors identified by high-throughput screening and defined by X-ray crystallography., Podust LM, von Kries JP, Eddine AN, Kim Y, Yermalitskaya LV, Kuehne R, Ouellet H, Warrier T, Altekoster M, Lee JS, Rademann J, Oschkinat H, Kaufmann SH, Waterman MR, Antimicrob Agents Chemother. 2007 Nov;51(11):3915-23. Epub 2007 Sep 10. PMID:17846131
Page seeded by OCA on Thu Feb 21 16:48:56 2008
Categories: Mycobacterium tuberculosis | Single protein | Sterol 14-demethylase | Kim, Y. | Kries, J P.Von. | Podust, L M. | Waterman, M R. | Yermalitskaya, L V. | CM6 | HEM | Heme | Heme lipid synthesis | Metal-binding | Monooxygenase | Nadp | Oxidoreductase | Protein-inhibitor complex | Steroid biosynthesis | Sterol biosynthesis
