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Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

With the increasing demand for blue dyes, it is of vital importance to develop a green and efficient biocatalyst to produce indigo. This study constructed a hydrogen peroxide-dependent catalytic system for the direct conversion of indole to indigo using P450BM3 with the assistance of dual-functional small molecules (DFSM). The arrangements of amino acids at 78, 87, and 268 positions influenced the catalytic activity. F87G/T268V mutant gave the highest catalytic activity with kcat of 1402 min−1 and with a yield of 73%. F87A/T268V mutant was found to produce the indigo product with chemoselectivity as high as 80%. Moreover, F87G/T268A mutant was found to efficiently catalyze indole oxidation with higher activity (kcat/Km = 1388 mM−1 min−1) than other enzymes, such as the NADPH-dependent P450BM3 (2.4-fold), the Ngb (32-fold) and the Mb (117-fold). Computer simulation results indicate that the arrangements of amino acid residues in the active site can significantly affect the catalytic activity of the protein. The DFSM-facilitated P450BM3 peroxygenase system provides an alternative, simple approach for a key step in the bioproduction of indigo. [ABSTRACT FROM AUTHOR]

Peptide nucleic acid (PNA) is an analog of natural nucleic acids, where the sugar-phosphate backbone of DNA is replaced by an electrostatically neutral N-(2-aminoethyl)glycine backbone. This unique peptide-based backbone enables PNAs to form a very stable duplex with the complementary nucleic acids via Watson–Crick base pairing since there is no electrostatic repulsion between PNA and DNA·RNA. With this high nucleic acid affinity, PNAs have been used in a wide range of fields, from biological applications such as gene targeting, to engineering applications such as probe and sensor developments. In addition to single-stranded DNA, PNA can also recognize double-stranded DNA (dsDNA) through the formation of a double-duplex invasion complex. This double-duplex invasion is hard to achieve with other artificial nucleic acids and is expected to be a promising method to recognize dsDNA in cellula or in vivo since the invasion does not require the prior denaturation of dsDNA. In this paper, we provide basic knowledge of PNA and mainly focus on the research of PNA invasion. [ABSTRACT FROM AUTHOR]

Using artificial hemes for the reconstruction of natural heme proteins represents a fascinating approach to enhance the bioactivity of the latter. We report the synthesis of various metal 5‐oxaporphyrinium cations as cofactors, and a cobalt 5‐oxaporphyrinium cation was successfully incorporated into the heme‐acquisition protein (HasA) secreted by Pseudomonas aeruginosa. We hypothesize that the oxaporphyrinium cation strongly binds to the HasA‐specific outer membrane receptor (HasR) due to its cationic charge, which prevents the subsequent acquisition of heme. In fact, the reconstructed HasA inhibited the growth of Pseudomonas aeruginosa and even of multidrug‐resistant P. aeruginosa. [ABSTRACT FROM AUTHOR]

We report an OmpF loop deletion mutant, which improves the cellular uptake of external additives into an Escherichia coli whole‐cell biocatalyst. Through co‐expression of the OmpF mutant with wild‐type P450BM3 in the presence of decoy molecules, the yield of the whole‐cell biotransformation of benzene could be considerably improved. Notably, with the decoy molecule C7AM‐Pip‐Phe the yield duodecupled from 5.7 % to 70 %, with 80 % phenol selectivity. The benzylic hydroxylation of alkyl‐ and cycloalkylbenzenes was also examined, and with the aid of decoy molecules, propylbenzene and tetralin were converted to 1‐hydroxylated products with 78 % yield and 94 % (R) ee for propylbenzene and 92 % yield and 94 % (S) ee for tetralin. Our results suggest that both the decoy molecule and substrate traverse the artificial OmpF channel, synergistically boosting whole‐cell bioconversions. [ABSTRACT FROM AUTHOR]

Using artificial hemes for the reconstruction of natural heme proteins represents a fascinating approach to enhance the bioactivity of the latter. We report the synthesis of various metal 5‐oxaporphyrinium cations as cofactors, and a cobalt 5‐oxaporphyrinium cation was successfully incorporated into the heme‐acquisition protein (HasA) secreted by Pseudomonas aeruginosa. We hypothesize that the oxaporphyrinium cation strongly binds to the HasA‐specific outer membrane receptor (HasR) due to its cationic charge, which prevents the subsequent acquisition of heme. In fact, the reconstructed HasA inhibited the growth of Pseudomonas aeruginosa and even of multidrug‐resistant P. aeruginosa. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CYP152A1 (cytochrome P450BSβ) is a fatty acid peroxygenase, which specifically catalyses the oxidation of long-chain fatty acids using hydrogen peroxide as an oxidant. We have found that CYP152A1 possesses catalase activity, which competes with the hydroxylation of long-chain fatty acids, the oxidation of non-native substrates, and haem degradation. Using hydrogen peroxide, Compound I of CYP152A1 could not be observed, due to its swift decomposition via catalase activity, where Compound I reacts with another molecule of hydrogen peroxide to form O2. In contrast, a clear spectral change indicative of Compound I formation was observed when mCPBA was employed as the oxidant. This work presents valuable insights into an important role for the catalase activity of CYP152A1 in avoiding enzyme deactivation when no substrate is available for oxidation. [ABSTRACT FROM AUTHOR]

Peptide nucleic acid can recognise sequences in double-stranded DNA (dsDNA) through the formation of a double-duplex invasion complex. This double-duplex invasion is a promising method for the recognition of dsDNA in cellula because peptide nucleic acid (PNA) invasion does not require the prior denaturation of dsDNA. To increase its applicability, we developed PNAs modified with a nuclear localisation signal (NLS) peptide. In this study, the characteristics of NLS-modified PNAs were investigated for the future design of novel peptide-modified PNAs. [ABSTRACT FROM AUTHOR]

We report the enhanced cis- and enantioselective cyclopropanation of styrene catalysed by cytochrome P450BM3 in the presence of dummy substrates, i.e. decoy molecules. With the aid of the decoy molecule R-Ibu-Phe, diastereoselectivity for the cis diastereomers reached 91%, and the enantiomeric ratio for the (1S,2R) isomer reached 94%. Molecular dynamics simulations underpin the experimental data, revealing the mechanism of how enantioselectivity is controlled by the addition of decoy molecules. [ABSTRACT FROM AUTHOR]

We prepared enzyme-immobilized hydrogels and investigated the effects of the cross-linking density and polymer properties on their oxidation reaction rate. The oxidation rate of enzyme-immobilized hydrogels increased as the cross-linking density in the hydrogels increased. In addition, we controlled the oxidation rate using hydrogels exhibiting an appropriate interaction with a decoy molecule in the hydrogel. [ABSTRACT FROM AUTHOR]

Despite CYP102A1 (P450BM3) representing one of the most extensively researched metalloenzymes, crystallisation of its haem domain upon modification can be a challenge. Crystal structures are indispensable for the efficient structure‐based design of P450BM3 as a biocatalyst. The abietane diterpenoid derivative N‐abietoyl‐l‐tryptophan (AbiATrp) is an outstanding crystallisation accelerator for the wild‐type P450BM3 haem domain, with visible crystals forming within 2 hours and diffracting to a near‐atomic resolution of 1.22 Å. Using these crystals as seeds in a cross‐microseeding approach, an assortment of P450BM3 haem domain crystal structures, containing previously uncrystallisable decoy molecules and diverse artificial metalloporphyrins binding various ligand molecules, as well as heavily tagged haem‐domain variants, could be determined. Some of the structures reported herein could be used as models of different stages of the P450BM3 catalytic cycle. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oligonucleotides represent powerful DNA-recognition tools, but the formation of undesirable "self-duplexes" becomes more probable with increasing DNA affinity. Herein, we have developed a modified nucleobase with "self-avoiding" properties. Facile methylation of guanine yields a cationic N7-methylguanine, which suppresses the formation of self-duplexes whilst improving DNA affinity through electrostatic interaction. [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]

Abstract: An Escherichia coli whole‐cell biocatalyst for the direct hydroxylation of benzene to phenol has been developed. By adding amino acid derivatives as decoy molecules to the culture medium, wild‐type cytochrome P450BM3 (P450BM3) expressed in E.coli can be activated and non‐native substrates hydroxylated, without supplementing with NADPH. The yield of phenol reached 59 % when N‐heptyl‐ l‐prolyl‐ l‐phenylalanine (C7‐Pro‐Phe) was employed as the decoy molecule. It was shown that decoy molecules, especially those lacking fluorination, reached the cytosol of E. coli, thus imparting in vivo catalytic activity for the oxyfunctionalisation of non‐native substrates to intracellular P450BM3. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

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]

Iron(III)-5,15-diphenylporphyrin and several derivatives were accommodated by HasA, a heme acquisition protein secreted by Pseudomonas aeruginosa, despite possessing bulky substituents at the meso position of the porphyrin. Crystal structure analysis revealed that the two phenyl groups at the meso positions of porphyrin extend outside HasA. It was shown that the growth of P. aeruginosa was inhibited in the presence of HasA coordinating the synthetic porphyrins under iron-limiting conditions, and that the structure of the synthetic porphyrins greatly affects the inhibition efficiency. [ABSTRACT FROM AUTHOR]

Iron(III)-5,15-diphenylporphyrin and several derivatives were accommodated by HasA, a heme acquisition protein secreted by Pseudomonas aeruginosa, despite possessing bulky substituents at the meso position of the porphyrin. Crystal structure analysis revealed that the two phenyl groups at the meso positions of porphyrin extend outside HasA. It was shown that the growth of P. aeruginosa was inhibited in the presence of HasA coordinating the synthetic porphyrins under iron-limiting conditions, and that the structure of the synthetic porphyrins greatly affects the inhibition efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Inhibition self‐assembly of β‐amyloid (Aβ) is considered to be a strategy that can be potentially useful to develop treatment for Alzheimer's disease (AD). We have discovered that a protein unit that is found in the fimbriae of Gram‐negative bacteria, which has a vacant site for a β‐sheet strand, prevents Aβ oligomerization effectively. Moreover, we found that a soluble but denatured form of this protein shows even higher potency. Our results also demonstrate the applicability of denatured proteins as pharmaceutical material. [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 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]

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. Keywords: Asymmetrische Katalyse; Kristallografie; Reaktionsmechanismen; Täuschmoleküle; Zytochrom P450 DE Asymmetrische Katalyse Kristallografie Reaktionsmechanismen Täuschmoleküle Zytochrom P450 1 1 1 03/15/23 20230320 NES 230320 B Enzymes b . [Extracted from the article]

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]

Cytochromes P450 (P450s) catalyze monooxygenation of a wide range of less reactive organic molecules under mild conditions. By contrast with the general reductive oxygen activation pathway of P450s, an HO-shunt pathway does not require any supply of electrons and protons for the generation of a highly reactive intermediate (compound I). Because the low cost of HO allows us to use it in industrial-scale synthesis, the HO-shunt pathway is an attractive process for monooxygenation reactions. This review focuses on the P450-catalyzed monooxygenation of organic molecules using HO as the oxidant. [ABSTRACT FROM AUTHOR]

The heme acquisition system A protein secreted by Pseudomonas aeruginosa (HasAp) can capture several synthetic metal complexes other than heme. The crystal structures of HasAp harboring synthetic metal complexes revealed only small perturbation of the overall HasAp structure. An inhibitory effect upon heme acquisition by HasAp bearing synthetic metal complexes was examined by monitoring the growth of Pseudomonas aeruginosa PAO1. HasAp bound to iron-phthalocyanine inhibits heme acquisition in the presence of heme-bound HasAp as an iron source. [ABSTRACT FROM AUTHOR]

The heme acquisition system A protein secreted by Pseudomonas aeruginosa (HasAp) can capture several synthetic metal complexes other than heme. The crystal structures of HasAp harboring synthetic metal complexes revealed only small perturbation of the overall HasAp structure. An inhibitory effect upon heme acquisition by HasAp bearing synthetic metal complexes was examined by monitoring the growth of Pseudomonas aeruginosa PAO1. HasAp bound to iron-phthalocyanine inhibits heme acquisition in the presence of heme-bound HasAp as an iron source. [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]

Playing tricks on enzymes: Direct hydroxylation of benzene to phenol was catalyzed by wild‐type P450BM3 in the presence of perfluorinated carboxylic acids as decoy molecules. The catalytic turnover rate reached 120 min−1 per P450. The selectivity towards phenol production was very high and no overoxidation products were detected. [ABSTRACT FROM AUTHOR]