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Catching the structure of cytochrome P450 enzymes in flagrante is crucial for the development of P450 biocatalysts, as most structures collected are found trapped in a precatalytic conformation. At the heart of P450 catalysis lies Cpd I, a short‐lived, highly reactive intermediate, whose recalcitrant nature has thwarted most attempts at capturing catalytically relevant poses of P450s. We report the crystal structure of P450BM3 mimicking the state in the precise moment preceding epoxidation, which is in perfect agreement with the experimentally observed stereoselectivity. This structure was attained by incorporation of the stable Cpd I mimic oxomolybdenum mesoporphyrin IX into P450BM3 in the presence of styrene. The orientation of styrene to the Mo‐oxo species in the crystal structures sheds light onto the dynamics involved in the rotation of styrene to present its vinyl group to Cpd I. This method serves as a powerful tool for predicting and modelling the stereoselectivity of P450 reactions. [ABSTRACT FROM AUTHOR]

A new type of high‐pressure reactor based on liquid‐flow pressurisation using a HPLC pump has been developed. This high‐pressure reactor allows the easy and safe performance of reactions with gaseous alkanes under high‐pressures up to 10 MPa (100 atm), without the need for high‐pressure gas cylinders. The amount of substrate gas required for a single reaction is very small compared with reactions using a conventional autoclave, which, when using expensive substrate gasses, such as 13C‐labelled ethane, becomes critical. Employing this high‐pressure reactor in conjunction with cytochrome P450BM3 and the assistance of decoy molecules, the direct hydroxylation of gaseous alkanes was drastically improved. At 5 MPa the TOF of propane hydroxylation increased 10‐fold, reaching 2200 min−1. Hydroxylation of ethane was also substantially accelerated at 5 MPa, reaching a TOF of 28 min−1. [ABSTRACT FROM AUTHOR]

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Haem substitution is an effective approach to tweak the function of haemoproteins. Herein, we report a facile haem substitution method for self-sufficient cytochrome P450BM3 (CYP102A1) from Bacillus megaterium utilising the transpeptidase Sortase A from Staphylococcus aureus. We successfully constructed Mn-substituted BM3 and investigated its catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: We report a unique strategy for the development of a H2O2‐dependent cytochrome P450BM3 system, which catalyzes the monooxygenation of non‐native substrates with the assistance of dual‐functional small molecules (DFSMs), such as N‐(ω‐imidazolyl fatty acyl)‐ l‐amino acids. The acyl amino acid group of DFSM is responsible for bounding to enzyme as an anchoring group, while the imidazolyl group plays the role of general acid–base catalyst in the activation of H2O2. This system affords the best peroxygenase activity for the epoxidation of styrene, sulfoxidation of thioanisole, and hydroxylation of ethylbenzene among those P450–H2O2 system previously reported. This work provides the first example of the activation of the normally H2O2‐inert P450s through the introduction of an exogenous small molecule. This approach improves the potential use of P450s in organic synthesis as it avoids the expensive consumption of the reduced nicotinamide cofactor NAD(P)H and its dependent electron transport system. This introduces a promising approach for exploiting enzyme activity and function based on direct chemical intervention in the catalytic process. [ABSTRACT FROM AUTHOR]

The selective hydroxylation of benzene to phenol, without the formation of side products resulting from overoxidation, is catalyzed by cytochrome P450BM3 with the assistance of amino acid derivatives as decoy molecules. The catalytic turnover rate and the total turnover number reached 259 min−1 P450BM3−1 and 40 200 P450BM3−1 when N-heptyl- l-proline modified with l-phenylalanine (C7- l-Pro- l-Phe) was used as the decoy molecule. This work shows that amino acid derivatives with a totally different structure from fatty acids can be used as decoy molecules for aromatic hydroxylation by wild-type P450BM3. This method for non-native substrate hydroxylation by wild-type P450BM3 has the potential to expand the utility of P450BM3 for biotransformations. [ABSTRACT FROM AUTHOR]

The heme of hydrogen peroxide-dependent cytochrome P450BSβ (P450BSβ) was removed by apomyoglobin under mild conditions to give apo-P450BSβ without the need for acidic conditions and organic solvents. The circular dichroism spectrum of the apo-P450BSβ was essentially identical to that of holo-P450BSβ, showing a small structural change resulting from the removal of heme using apomyoglobin. The apo-P450BSβ was reconstituted with hemin or manganese protoporphyrin IX (MnPPIX), and the resulting reconstituted P450BSβ catalyzed the one-electron oxidation of guaiacol using hydrogen peroxide as an oxidant. A higher catalytic activity was observed for P450BSβ reconstituted with MnPPIX when meta-chloroperoxybenzoic acid (mCPBA) was used as the oxidant. [ABSTRACT FROM AUTHOR]

Keywords: Asymmetric Catalysis; Crystallography; Cytochrome P450; Decoy Molecules; Reaction Mechanisms EN Asymmetric Catalysis Crystallography Cytochrome P450 Decoy Molecules Reaction Mechanisms 1 1 1 03/15/23 20230320 NES 230320 B Enzymes b . In their Research Article (e202215706), Hiroshi Sugimoto, Osami Shoji et al. report the crystal structure of cytochrome P450BM3 mimicking the state of the enzyme in the moment preceding epoxidation. Frontispiece: A Compound I Mimic Reveals the Transient Active Species of a Cytochrome P450 Enzyme: Insight into the Stereoselectivity of P450-Catalysed Oxidations. [Extracted from the article]

Enzyme performance can be improved using decoy molecules or engineered variants to accelerate the activity without affecting selectivity. Here we combine a rate accelerator variant of cytochrome P450Bm3 with decoy molecules to enhance the oxidation activity of a range of small organic molecules. This combined approach offers superior biocatalytic efficiency without modifying the product distribution. [ABSTRACT FROM AUTHOR]

Cytochrome P450SPα (P450SPα) and cytochrome P450BSβ (P450BSβ) belonging to the CYP152 family of enzymes (CYP152s) can utilize H2O2 efficiently as an oxidant for the generation of compound I. Although P450SPα and P450BSβ have very high substrate specificity and catalyse hydroxylation of long-chain fatty acids exclusively, we found that they can oxidize non-native substrates such as styrene simply by including medium chain length n-alkyl carboxylic acids as “decoy molecules.” Although we had assumed that acetic acid did not serve as a decoy molecule, P450SPα and P450BSβ efficiently catalysed oxidation of non-native substrates when the reaction was carried out at a high concentration of acetate anion. The turnover rate for epoxidation of styrene catalysed by P450BSβ in the presence of 1 M acetate anion reached 590 ± 30 min−1. [ABSTRACT FROM AUTHOR]

To bring out the potential of wild-type cytochrome P450s, we have developed a series of 'decoy molecules' to change their high substrate specificity without any mutagenesis. Decoy molecules are inert dummy substrates with structures that are very similar to those of natural substrates. The decoy molecules force long-alkyl-chain fatty acid hydroxylases (P450BSβ, P450SPα, and P450BM3) to generate the active species and to catalyze oxidation of various substrates other than fatty acids. Interestingly, the catalytic activity was highly dependent on the structure of decoy molecules. Furthermore, the enantioselectivity of reactions catalyzed by P450BSβ and P450SPα was also dependent on the structure of decoy molecules. The decoy molecule system allows us to control reactions catalyzed by wild-type enzymes by designing decoy molecules. [ABSTRACT FROM AUTHOR]

Tricks mit Enzymen: Die direkte Hydroxylierung von Benzol zu Phenol wurde durch Wildtyp ‐ P450BM3 in der Gegenwart von perfluorierten Carbonsäuren als Ködermolekülen katalysiert. Der katalytische Umsatz erreichte 120 min−1 pro P450. Die Selektivität für die Phenolbildung war sehr hoch, und Produkte einer Überoxidation wurden nicht nachgewiesen. [ABSTRACT FROM AUTHOR]

Cytochrome P450SPα (CYP152B1) isolated from Sphingomonas paucimobilis is the first P450 to be classified as a H2O2-dependent P450. P450SPα hydroxylates fatty acids with high α-regioselectivity. Herein we report the crystal structure of P450SPα with palmitic acid as a substrate at a resolution of 1.65 Å. The structure revealed that the Ca of the bound palmitic acid in one of the alternative conformations is 4.5 Å from the heme iron. This conformation explains the highly selective α-hydroxylation of fatty acid observed in P450SPα. Mutations at the active site and the F-G loop of P450SPα did not impair its regioselectivity. The crystal structures of mutants (L78F and F288G) revealed that the location of the bound palmitic acid was essentially the same as that in the WT, although amino acids at the active site were replaced with the corresponding amino acids of cytochrome P450BSβ (CYP152A1), which shows β-regioselectivity. This implies that the high regioselectivity of P450SPα is caused by the orientation of the hydrophobic channel, which is more perpendicular to the heme plane than that of P450BSβ. [ABSTRACT FROM AUTHOR]

Keywords: cytochrome P450; whole-cell biocatalyst; decoy molecules; benzene hydroxylation; stereoselective oxidation EN cytochrome P450 whole-cell biocatalyst decoy molecules benzene hydroxylation stereoselective oxidation 1 1 1 02/03/22 20220207 NES 220207 B A loop deletion mutant b of outer membrane protein F (OmpF) that facilitates the cellular uptake of decoy molecules into I Escherichia coli i has been developed. Inside Cover: Designer Outer Membrane Protein Facilitates Uptake of Decoy Molecules into a Cytochrome P450BM3-Based Whole-Cell Biocatalyst (Angew. Cytochrome P450, whole-cell biocatalyst, decoy molecules, benzene hydroxylation, stereoselective oxidation. [Extracted from the article]

Abstract: The enantioselectivity in the sulfoxidation of thioanisole catalyzed by cytochrome P450BSβ with a decoy molecule, a dummy molecule of the natural substrate, can be inverted by changing the structure of the decoy molecule. The methodology demonstrated herein shows the potential for controlling the stereoselectivity of biocatalysts without any mutagenesis. [Copyright &y& Elsevier]

Front Cover: Development of a High-Pressure Reactor Based on Liquid-Flow Pressurisation to Facilitate Enzymatic Hydroxylation of Gaseous Alkanes (ChemCatChem 19/2019) Direct hydroxylation of gaseous alkanes by cytochrome P450BM3 with assistance of decoy molecules was drastically improved using this high-pressure reactor. The TOF of propane-hydroxylation reached 2200/min under 5 MPa of propane. [Extracted from the article]

Hydroxylierung In der Zuschrift auf S. 10460 beschreiben O. Shoji, Y. Watanabe et al. die Verwendung von bestimmten Aminosäurederivaten für die Aktivierung von Cytochrom P450BM3 zur direkten Hydroxylierung von Benzol zu Phenol. [ABSTRACT FROM AUTHOR]

The wild-type cytochrome P450 (CYP) monooxygenase enzyme CYP102A1 (P450Bm3) has low activity for cycloalkane oxidation. The oxidation of these substrates by variants of this enzyme in combination with perfluorinated decoy molecules (PFCs) was investigated to improve productivity. The use of rate accelerating variants, which have mutations located outside of the substrate binding pocket as well as an active site variant of CYP102A1 (A74G/F87V/L188Q) all enhanced cycloalkane oxidation (C5 to C10). The addition of the decoy molecules to the wild-type and the rate accelerating mutants of CYP102A1 boosted the substrate oxidation rates even further. However, the levels of cycloalkanol product decreased with the larger alkanes when the decoy molecules were used with the variant A74G/F87V/L188Q, which contained mutations within the substrate binding pocket. For the majority of the enzymes and PFC decoy molecule combinations the highest levels of oxidation were obtained with cyclooctane. When larger second generation decoy molecules, based on modified amino acids were utilised there was a significant improvement in the oxidation of the smaller cycloalkanes by the wild-type enzyme and one other variant. This resulted in significant improvements in biocatalytic oxidation of cyclopentane and cyclohexane. However, the use of these optimised decoy molecules did not significantly improve cycloalkane oxidation over the fluorinated fatty acid derivatives when combined with the best rate accelerating variant, R47L/Y51F/I401P. Overall our approach enabled the cycloalkanes to be oxidised 300- to 8000-fold more efficiently than the wild-type enzyme at product formation rates in excess of 500 and up to 1700 nmol·nmol-CYP −1 ·min −1 . [ABSTRACT FROM AUTHOR]

Abstract 2,3′,4,4′,5-Pentachlorobiphenyl (CB118) is one of the most abundant polychlorinated biphenyl (PCB) congeners in the environment, and perfluoroalkyl acids, including perfluorocarboxylic acids (PFCAs), are widely distributed in the environment. Although CB118 and perfluoroalkyl acids are present in all humans and biota, effects in the metabolic fate of CB118 leading to toxicity change are unclear. P450BM3, which is isolated from the soil bacterium Bacillus megaterium , metabolized CB118 to three different hydroxylated pentachlorobiphenyls (M1-M3). M2 was identified as 4′-OH-2,3′,4,5,5′-pentachlorobiphenyl. These reactions were promoted by the presence of PFCAs, and perfluorooctanoic acid (PFCA-C8) was the most effective for accelerating these reactions among PFCAs with different carbon chain length. The production rate of M2 was accelerated by 25-times using PFCA-C8. Furthermore, the docking models of P450BM3 with CB118 and PFCAs revealed that the conformational changes of the substrate-binding cavity of P450BM3 after binding of PFCAs to P450BM3 were important for selective production of CB118 metabolites. This study leads to the clarification of the different metabolic fates of PCBs under complex contamination with PFCAs. Graphical abstract Image 1 Highlights • Bacterial P450BM3 metabolized CB118 to hydroxylated metabolites. • Hydroxylation of CB118 was promoted by the existence of PFCAs. • The size of the substrate-binding cavity of P450BM3 was changed by binding PFCAs. • Metabolic fates of PCBs under complex contamination with PFCAs may be different. [ABSTRACT FROM AUTHOR]

Cytochrome P450 enzymes (CYPs) have attracted much promise as biocatalysts in a push for cleaner and more environmentally friendly catalytic systems. However, changing the substrate specificity of CYPs, such as CYP102A1, can be a challenging task, requiring laborious mutagenesis. An alternative approach is the use of decoy molecules that "trick" the enzyme into becoming active by impersonating the native substrate. Whilst the decoy molecule system has been extensively developed for CYP102A1, its general applicability for other CYP102-family enzymes has yet to be shown. Herein, we demonstrate that decoy molecules can "trick" CYP102A5 and A7 into becoming active and hydroxylating non-native substrates. Furthermore, significant differences in decoy molecule selectivity as well as decoy molecule binding were observed. The X-ray crystal structure of the CYP102A5 haem domain was solved at 2.8 Å, delivering insight into a potential substate-binding site that differs significantly from CYP102A1. Decoy molecules were shown to be compatible for use with both CYP102A5 and CYP102A7. Both CYP102A5 and CYP102A7 displayed a unique and unexpected decoy molecule preference. The crystal structure of CYP102A5 was solved at a resolution of 2.8 Å. [Display omitted] • Decoy molecules were shown to be compatible for use with both CYP102A5 and A7. • Both CYP102A5 and A7 displayed a unique and unexpected decoy molecule preference. • Decoy molecules were found to bind in a two-step fashion to CYP102A5 and A7 that was not observed for A1. • We report the first structure of CYP102A5 at a resolution of 2.8 Å. • The structure of CYP102A5 reveals a potential binding site that differs significantly from the CYP102A1 reference system. [ABSTRACT FROM AUTHOR]