3QWF

Crystal structure of the 17beta-hydroxysteroid dehydrogenase from Cochliobolus lunatus

Summary for 3QWF

• Entry DOI: 10.2210/pdb3qwf/pdb
• Related: 3IS3 3ITD 3QWH 3QWI
• Descriptor: 17beta-hydroxysteroid dehydrogenase, GLYCEROL, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, ... (4 entities in total)
• Functional Keywords: hydroxysteroid dehydrogenase, short chain dehydrogenase/reductase, sdr steroid, fungi, cochliobolus lunatus, rossmann fold, cytosol, oxidoreductase
• Biological source: Cochliobolus lunatus
• Total number of polymer chains: 8
• Total formula weight: 238360.54

Authors

Cassetta, A.,Lamba, D.,Krastanova, I.,Stojan, J.,Lanisnik-Rizner, T.,Kristan, K.,Brunskole, M. (deposition date: 2011-02-28, release date: 2012-01-18, Last modification date: 2023-09-13)

Primary citation

Cassetta, A.,Krastanova, I.,Kristan, K.,Brunskole Svegelj, M.,Lamba, D.,Lanisnik Rizner, T.,Stojan, J.
Structural Studies on a Fungal 17Beta-Hydroxysteroid Dehydrogenase
Biochem.J., 441:151-160, 2012

PubMed Abstract: The 17β-HSD (17β-hydroxysteroid dehydrogenase) from the filamentous fungus Cochliobolus lunatus (17β-HSDcl) is a NADP(H)-dependent enzyme that preferentially catalyses the interconversion of inactive 17-oxo-steroids and their active 17β-hydroxy counterparts. 17β-HSDcl belongs to the SDR (short-chain dehydrogenase/reductase) superfamily. It is currently the only fungal 17β-HSD member that has been described and represents one of the model enzymes of the cP1 classical subfamily of NADPH-dependent SDR enzymes. A thorough crystallographic analysis has been performed to better understand the structural aspects of this subfamily and provide insights into the evolution of the HSD enzymes. The crystal structures of the 17β-HSDcl apo, holo and coumestrol-inhibited ternary complex, and the active-site Y167F mutant reveal subtle conformational differences in the substrate-binding loop that probably modulate the catalytic activity of 17β-HSDcl. Coumestrol, a plant-derived non-steroidal compound with oestrogenic activity, inhibits 17β-HSDcl [IC50 2.8 μM; at 100 μM substrate (4-oestrene-3,17-dione)] by occupying the putative steroid-binding site. In addition to an extensive hydrogen-bonding network, coumestrol binding is stabilized further by π-π stacking interactions with Tyr212. A stopped-flow kinetic experiment clearly showed the coenzyme dissociation as the slowest step of the reaction and, in addition to the low steroid solubility, it prevents the accumulation of enzyme-coenzyme-steroid ternary complexes.

PubMed: 21929506
DOI: 10.1042/BJ20110567

Experimental method

X-RAY DIFFRACTION (1.88 Å)