7Q89

OleP mutant G92W in complex with 6DEB

Summary for 7Q89

• Entry DOI: 10.2210/pdb7q89/pdb
• Related: 7q6r 7q6x
• Descriptor: Cytochrome P-450, PROTOPORPHYRIN IX CONTAINING FE, 6-DEOXYERYTHRONOLIDE B, ... (7 entities in total)
• Functional Keywords: oxidoreductase, cytochrome p450, oleandomicine, olep, mutant, 6deb
• Biological source: Streptomyces antibioticus
• Total number of polymer chains: 6
• Total formula weight: 285104.55

Authors

Savino, C.,Montemiglio, L.C.,Vallone, B.,Exertier, C.,Freda, I.,Gugole, E. (deposition date: 2021-11-10, release date: 2022-01-26, Last modification date: 2024-01-31)

Primary citation

Montemiglio, L.C.,Gugole, E.,Freda, I.,Exertier, C.,D'Auria, L.,Chen, C.G.,Nardi, A.N.,Cerutti, G.,Parisi, G.,D'Abramo, M.,Savino, C.,Vallone, B.
Point Mutations at a Key Site Alter the Cytochrome P450 OleP Structural Dynamics.
Biomolecules, 12:-, 2021

PubMed Abstract: Substrate binding to the cytochrome P450 OleP is coupled to a large open-to-closed transition that remodels the active site, minimizing its exposure to the external solvent. When the aglycone substrate binds, a small empty cavity is formed between the I and G helices, the BC loop, and the substrate itself, where solvent molecules accumulate mediating substrate-enzyme interactions. Herein, we analyzed the role of this cavity in substrate binding to OleP by producing three mutants (E89Y, G92W, and S240Y) to decrease its volume. The crystal structures of the OleP mutants in the closed state bound to the aglycone 6DEB showed that G92W and S240Y occupied the cavity, providing additional contact points with the substrate. Conversely, mutation E89Y induces a flipped-out conformation of this amino acid side chain, that points towards the bulk, increasing the empty volume. Equilibrium titrations and molecular dynamic simulations indicate that the presence of a bulky residue within the cavity impacts the binding properties of the enzyme, perturbing the conformational space explored by the complexes. Our data highlight the relevance of this region in OleP substrate binding and suggest that it represents a key substrate-protein contact site to consider in the perspective of redirecting its activity towards alternative compounds.

PubMed: 35053203
DOI: 10.3390/biom12010055

Experimental method

X-RAY DIFFRACTION (2.08 Å)