Rational design of thermophilic CYP119 for progesterone hydroxylation by in silico mutagenesis and docking screening

Small angle X-ray scattering analysis of thermophilic cytochrome P450 CYP119 and the effects of the N-terminal histidine tag

Combining size exclusion chromatography-small angle X-ray scattering (SEC-SAXS) and molecular dynamics (MD) analysis is a promising approach to investigate protein behavior in solution, particularly for understanding conformational changes due to substrate binding in cytochrome P450s (CYPs). This study investigates conformational changes in CYP119, a thermophilic CYP from Sulfolobus acidocaldarius that exhibits structural flexibility similar to mammalian CYPs. Although the crystal structure of ligand-free (open state) and ligand-bound (closed state) forms of CYP119 is known, the overall structure of the enzyme in solution has not been explored until now. It was found that theoretical scattering profiles from the crystal structures of CYP119 did not align with the SAXS data, but conformers from MD simulations, particularly starting from the open state (46 % of all frames), agreed well. Interestingly, a small percentage of closed-state conformers also fit the data (9 %), suggesting ligand-free CYP119 samples ligand-bound conformations. Ab initio SAXS models for N-His tagged CYP119 revealed a tail-like unfolded structure impacting protein flexibility, which was confirmed by in silico modeling. SEC-SAXS analysis of N-His CYP119 indicated pentameric structures in addition to monomers in solution, affecting the stability and activity of the enzyme. This study adds insights into the conformational dynamics of CYP119 in solution.

Efficient biocatalytic C-H bond oxidation: an engineered heme-thiolate peroxygenase from a thermostable cytochrome P450

A highly sought after reaction in chemical synthesis is the activation of unactivated carbon-hydrogen bonds. We demonstrate the hydroxylation of fatty acids using an engineered thermostable archaeal cytochrome P450 enzyme. By replacing a seven amino acid section of the I-helix, the nicotinamide cofactor-dependent monooxygenase was converted into a hydrogen peroxide using peroxygenase, enabling the efficient biocatalytic oxidation of C-H bonds at room temperature to 90 °C.