7TRU

The crystal structure of WT CYP199A4 bound to 4-(thiophen-2-yl)benzoic acid

Summary for 7TRU

• Entry DOI: 10.2210/pdb7tru/pdb
• Descriptor: Cytochrome P450, 4-(thiophen-2-yl)benzoic acid, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• Functional Keywords: cytochrome p450, thiophene sulfoxidation, oxidoreductase
• Biological source: Rhodopseudomonas palustris
• Total number of polymer chains: 1
• Total formula weight: 45443.62

Authors

Podgorski, M.N.,Bell, S.G. (deposition date: 2022-01-31, release date: 2023-03-15, Last modification date: 2023-10-25)

Primary citation

Podgorski, M.N.,Keto, A.B.,Coleman, T.,Bruning, J.B.,De Voss, J.J.,Krenske, E.H.,Bell, S.G.
The Oxidation of Oxygen and Sulfur-Containing Heterocycles by Cytochrome P450 Enzymes.
Chemistry, 29:e202301371-e202301371, 2023

PubMed Abstract: The cytochrome P450 (CYP) superfamily of monooxygenase enzymes play important roles in the metabolism of molecules which contain heterocyclic, aromatic functional groups. Here we study how oxygen- and sulfur-containing heterocyclic groups interact with and are oxidized using the bacterial enzyme CYP199A4. This enzyme oxidized both 4-(thiophen-2-yl)benzoic acid and 4-(thiophen-3-yl)benzoic acid almost exclusively via sulfoxidation. The thiophene oxides produced were activated towards Diels-Alder dimerization after sulfoxidation, forming dimeric metabolites. Despite X-ray crystal structures demonstrating that the aromatic carbon atoms of the thiophene ring were located closer to the heme than the sulfur, sulfoxidation was still favoured with 4-(thiophen-3-yl)benzoic acid. These results highlight a preference of this cytochrome P450 enzyme for sulfoxidation over aromatic hydroxylation. Calculations predict a strong preference for homodimerization of the enantiomers of the thiophene oxides and the formation of a single major product, in broad agreement with the experimental data. 4-(Furan-2-yl)benzoic acid was oxidized to 4-(4'-hydroxybutanoyl)benzoic acid using a whole-cell system. This reaction proceeded via a γ-keto-α,β-unsaturated aldehyde species which could be trapped in vitro using semicarbazide to generate a pyridazine species. The combination of the enzyme structures, the biochemical data and theoretical calculations provides detailed insight into the formation of the metabolites formed from these heterocyclic compounds.

PubMed: 37338048
DOI: 10.1002/chem.202301371

Experimental method

X-RAY DIFFRACTION (1.454 Å)