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1h5z
From Proteopedia
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CYTOCHROME P450 14 ALPHA-STEROL DEMETHYLASE (CYP51) FROM MYCOBACTERIUM TUBERCULOSIS IN FERRIC LOW-SPIN STATE
Overview
Sterol 14alpha-demethylases (CYP51) are essential enzymes in sterol, biosynthesis in eukaryotes and drug targets in antifungal therapy. Here, we report CYP51 structures in ligand-free and estriol bound forms. Using, estriol as a probe, we determined orientation of the substrate in the, active site, elucidated protein contacts with the invariant 3beta-hydroxy, group of a sterol, and identified F78 as a key discriminator between, 4alpha-methylated and 4alpha,beta-dimethylated substrates. Analysis of, CYP51 dynamics revealed that the C helix undergoes helix-coil transition, upon binding and dissociation of a ligand. Loss of helical structure of, the C helix in the ligand-free form results in an unprecedented opening of, the substrate binding site. Upon binding of estriol, the BC loop loses, ... [(full description)]
About this Structure
1H5Z is a [Single protein] structure of sequence from [Mycobacterium tuberculosis] with FE2 and HEM as [ligands]. Active as [Sterol 14-demethylase], with EC number [1.14.13.70]. Structure known Active Site: HEM. Full crystallographic information is available from [OCA].
Reference
Estriol bound and ligand-free structures of sterol 14alpha-demethylase., Podust LM, Yermalitskaya LV, Lepesheva GI, Podust VN, Dalmasso EA, Waterman MR, Structure. 2004 Nov;12(11):1937-45. PMID:15530358
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