4UYL

Crystal structure of sterol 14-alpha demethylase (CYP51B) from a pathogenic filamentous fungus Aspergillus fumigatus in complex with VNI

Summary for 4UYL

• Entry DOI: 10.2210/pdb4uyl/pdb
• Related: 4UYM
• Descriptor: 14-ALPHA STEROL DEMETHYLASE, PROTOPORPHYRIN IX CONTAINING FE, N-[(1R)-1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethyl]-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide, ... (4 entities in total)
• Functional Keywords: cytochrome p450, oxidoreductase, monooxygenase, sterol biosynthesis, eukaryotic membranes, cytochrome p450 fold, endoplasmic reticulum membrane, oxidoreductase-oxidoreductase inhibitor complex
• Biological source: ASPERGILLUS FUMIGATUS
• Total number of polymer chains: 2
• Total formula weight: 108741.33

Authors

Hargrove, T.Y.,Wawrzak, Z.,Lepesheva, G.I. (deposition date: 2014-09-01, release date: 2015-08-19, Last modification date: 2024-01-10)

Primary citation

Hargrove, T.Y.,Warwzak, Z.,Lamb, D.C.,Guengerich, F.P.,Lepesheva, G.I.
Structure-Functional Characterization of Cytochrome P450 Sterol Alpha-Demethylase (Cyp51B) from Aspergillus Fumigatus and Molecular Basis for the Development of Antifungal Drugs
J.Biol.Chem., 290:23916-, 2015

PubMed Abstract: Aspergillus fumigatus is the opportunistic fungal pathogen that predominantly affects the immunocompromised population and causes 600,000 deaths/year. The cytochrome P450 51 (CYP51) inhibitor voriconazole is currently the drug of choice, yet the treatment efficiency remains low, calling for rational development of more efficient agents. A. fumigatus has two CYP51 genes, CYP51A and CYP51B, which share 59% amino acid sequence identity. CYP51B is expressed constitutively, whereas gene CYP51A is reported to be inducible. We expressed, purified, and characterized A. fumigatus CYP51B, including determination of its substrate preferences, catalytic parameters, inhibition, and x-ray structure in complexes with voriconazole and the experimental inhibitor (R)-N-(1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethyl)-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide (VNI). The enzyme demethylated its natural substrate eburicol and the plant CYP51 substrate obtusifoliol at steady-state rates of 17 and 16 min(-1), respectively, but did not metabolize lanosterol, and the topical antifungal drug miconazole was the strongest inhibitor that we identified. The x-ray crystal structures displayed high overall similarity of A. fumigatus CYP51B to CYP51 orthologs from other biological kingdoms but revealed phylum-specific differences relevant to enzyme catalysis and inhibition. The complex with voriconazole provides an explanation for the potency of this relatively small molecule, whereas the complex with VNI outlines a direction for further enhancement of the efficiency of this new inhibitory scaffold to treat humans afflicted with filamentous fungal infections.

PubMed: 26269599
DOI: 10.1074/JBC.M115.677310

Experimental method

X-RAY DIFFRACTION (2.81 Å)