Unspecific peroxygenase enabled formation of azoxy compounds.

Enzymes are making a significant impact on chemical synthesis. However, the range of chemical products achievable through biocatalysis is still limited compared to the vast array of products possible with organic synthesis. For instance, azoxy products have rarely been synthesized using enzyme catalysts.

A Photoenzymatic Pathway for Gram-Scale Synthesis of 25-Hydroxyvitamin D.

Vitamin D and its analogues play a crucial role in promoting the well-being of both humans and animals. However, the current synthesis of this vital class of nutrients heavily relies on chemical transformations, which suffer from low step- and atom-efficiency due to lengthy synthetic pathways. To enhance sustainability in the chemical industry, it is necessary to develop alternative synthetic processes.

Peroxygenase-Enabled Reductive Kinetic Resolution for the Enantioenrichment of Organoperoxides.

Enantiomerically pure organoperoxides serve as valuable precursors in organic transformations. Herein, we present the first examples of unspecific peroxygenase catalyzed kinetic resolution of racemic organoperoxides through asymmetric reduction. Through meticulous investigation of the reaction conditions, it is shown that the unspecific peroxygenase from Agrocybe aegerita (AaeUPO) exhibits robust catalytic activity in the kinetic resolution reactions of the model substrate with turnover numbers up to 60000 and turnover frequency of 5.

Reaction engineering blocks ether cleavage for synthesizing chiral cyclic hemiacetals catalyzed by unspecific peroxygenase.

Hemiacetal compounds are valuable building blocks in synthetic chemistry, but their enzymatic synthesis is limited and often hindered by the instability of hemiacetals in aqueous environments. Here, we show that this challenge can be addressed through reaction engineering by using immobilized peroxygenase from Agrocybe aegerita (AaeUPO) under neat reaction conditions, which allows for the selective C-H bond oxyfunctionalization of environmentally significant cyclic ethers to cyclic hemiacetals. A wide range of chiral cyclic hemiacetal products are prepared in >99% enantiomeric excess and 95170 turnover numbers of AaeUPO.

Deciphering cell wall sensors enabling the construction of robust P. pastoris for single-cell protein production.

Single-cell protein (SCP) production in the methylotrophic yeast Pichia pastoris has the potential to achieve a sustainable protein supply. However, improving the methanol fermentation efficiency and reducing carbon loss has been a long-standing challenge with far-reaching scientific and practical implications. Here, comparative transcriptomics revealed that PAS_0305, a gene directly associated with cell wall thickness under methanol stress, can be used as a target for unlocking cell wall sensors.

Peroxygenase-Catalysed Sulfoxidations in Non-Aqueous Media.

Chiral sulfoxides are valuable building blocks in asymmetric synthesis. However, the biocatalytic synthesis of chiral sulfoxides is still challenged by low product titres. Herein, we report the use of peroxygenase as a catalyst for asymmetric sulfoxidation under non-aqueous conditions.

Immobilization protects enzymes from plasma-mediated inactivation.

Non-thermal plasmas are used in various applications to inactivate biological agents or biomolecules. A complex cocktail of reactive species, (vacuum) UV radiation and in some cases exposure to an electric field together cause the detrimental effects. In contrast to this disruptive property of technical plasmas, we have shown previously that it is possible to use non-thermal plasma-generated species such as HO as cosubstrates in biocatalytic reactions.

A Simple Access to γ- and ε-Keto Arenes via Enzymatic Divergent C─H Bond Oxyfunctionalization.

Performing divergent C─H bond functionalization on molecules with multiple reaction sites is a significant challenge in organic chemistry. Biocatalytic oxyfunctionalization reactions of these compounds to the corresponding ketones/aldehydes are typically hindered by selectivity issues. To address these challenges, the catalytic performance of oxidoreductases is explored.

HO-driven enzymatic oxyfunctionalization of tertiary C-H bonds.

Peroxygenase from catalyses the selective hydroxylation of tertiary C-H bonds, whereby tertiary alcohols, diols, ketols, ., were obtained in good to high regioselectivity and turnover numbers. This method can also be expanded for late-stage functionalization of drug molecules, which represents a streamlined synthetic method to give access to useful compounds.

A tRNAModification-based strategy for Identifying amiNo acid Overproducers (AMINO).

Amino acids have a multi-billion-dollar market with rising demand, prompting the development of high-performance microbial factories. However, a general screening strategy applicable to all proteinogenic and non-proteinogenic amino acids is still lacking. Modification of the critical structure of tRNA could decrease the aminoacylation level of tRNA catalyzed by aminoacyl-tRNA synthetases.

Green light enhanced the photostability and catalytic performance of fatty acid photodecarboxylase.

Green light was documented to improve the photostability of fatty acid photodecarboxylase from (FAP). Compared to blue light, green light increased the pentadecane yield by 27.6% and improved the residual activity of FAP to 5.

Engineering a Highly Regioselective Fungal Peroxygenase for the Synthesis of Hydroxy Fatty Acids.

The hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. In this study, we have engineered a highly regioselective fungal peroxygenase for the ω-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward subterminal hydroxylation with a drop in the over-oxidation activity.

Rational enzyme design for enabling biocatalytic Baldwin cyclization and asymmetric synthesis of chiral heterocycles.

Chiral heterocyclic compounds are needed for important medicinal applications. We report an in silico strategy for the biocatalytic synthesis of chiral N- and O-heterocycles via Baldwin cyclization modes of hydroxy- and amino-substituted epoxides and oxetanes using the limonene epoxide hydrolase from Rhodococcus erythropolis. This enzyme normally catalyzes hydrolysis with formation of vicinal diols.

Photoenzymatic decarboxylation: A promising way to produce sustainable aviation fuels and fine chemicals.

As one of the fastest-growing carbon emission sources, the aviation sector is severely restricted by carbon emission reduction targets. Sustainable aviation fuel (SAF) has emerged as the most potential alternative to traditional aviation fuel, but harsh production technologies limit its commercialization. Fatty acids photodecarboxylase from Chlorella variabilis NC64A (CvFAP), the latest discovered photoenzyme, provides promising approaches to produce various carbon-neutral biofuels and fine chemicals.

Chemoenzymatic Synthesis of Sterically Hindered Biaryls by Suzuki Coupling and Vanadium Chloroperoxidase Catalyzed Halogenations.

Halogenated biaryls are vital structural skeletons in bioactive products. In this study, an effective chemoenzymatic halogenation by vanadium-dependent chloroperoxidase from Camponotus inaequalis (CiVCPO) enabled the transformation of freely rotating biaryl bonds to sterically hindered axis. The yields were up to 84 % for the tribrominated biaryl products and up to 65 % when isolated.

Photobiocatalytic Decarboxylation for the Synthesis of Fatty Epoxides from Renewable Fatty Acids.

Fatty epoxides are unique building blocks in organic transformations and materials production; however, their synthetic methodologies are currently not accessible from renewable fatty acids. Herein, a photoenzymatic decarboxylation of epoxy fatty acids into fatty epoxides was demonstrated using fatty acid photodecarboxylase (FAP) from Chlorella variabilis NC64A (CvFAP). Various fatty epoxides were synthesized in excellent selectivity by wild-type CvFAP.

Synthesis of Enantioenriched Sulfoxides by an Oxidation-Reduction Enzymatic Cascade.

Chiral sulfoxides are versatile synthons and have gained a particular interest in asymmetric synthesis of active pharmaceutical and agrochemical ingredients. Herein, a linear oxidation-reduction bienzymatic cascade to synthesize chiral sulfoxides is reported. The extraordinarily stable and active vanadium-dependent chloroperoxidase from Curvularia inaequalis (CiVCPO) was used to oxidize sulfides into racemic sulfoxides, which were then converted to chiral sulfoxides by highly enantioselective methionine sulfoxide reductase A (MsrA) and B (MsrB) by kinetic resolution, respectively.

On the Versatility of Nanozeolite Linde Type L for Biomedical Applications: Zirconium-89 Radiolabeling and In Vivo Positron Emission Tomography Study.

Porous materials, such as zeolites, have great potential for biomedical applications, thanks to their ability to accommodate positively charged metal-ions and their facile surface functionalization. Although the latter aspect is important to endow the nanoparticles with chemical/colloidal stability and desired biological properties, the possibility for simple ion-exchange enables easy switching between imaging modalities and/or combination with therapy, depending on the envisioned application. In this study, the nanozeolite Linde type L (LTL) with already confirmed magnetic resonance imaging properties, generated by the paramagnetic gadolinium (Gd) in the inner cavities, was successfully radiolabeled with a positron emission tomography (PET)-tracer zirconium-89 (Zr).

Peroxygenase-Catalyzed Selective Synthesis of Calcitriol Starting from Alfacalcidol.

Calcitriol is an active analog of vitamin D3 and has excellent physiological activities in regulating healthy immune function. To synthesize the calcitriol compound, the concept of total synthesis is often adopted, which typically involves multiple steps and results in an overall low yield. Herein, we envisioned an enzymatic approach for the synthesis of calcitriol.

A Biocatalytic Platform for the Synthesis of Enantiopure Propargylic Alcohols and Amines.

Propargylic alcohols and amines are versatile building blocks in organic synthesis. We demonstrate a straightforward enzymatic cascade to synthesize enantiomerically pure propargylic alcohols and amines from readily available racemic starting materials. In the first step, the peroxygenase from converted the racemic propargylic alcohols into the corresponding ketones, which then were converted into the enantiomerically pure alcohols using the ()-selective alcohol dehydrogenase from or the ()-selective alcohol dehydrogenase from .

Chemoenzymatic Hunsdiecker-Type Decarboxylative Bromination of Cinnamic Acids.

In this contribution, we report chemoenzymatic bromodecarboxylation (Hunsdiecker-type) of α,ß-unsaturated carboxylic acids. The extraordinarily robust chloroperoxidase from (VCPO) generated hypobromite from HO and bromide, which then spontaneously reacted with a broad range of unsaturated carboxylic acids and yielded the corresponding vinyl bromide products. Selectivity issues arising from the (here undesired) addition of water to the intermediate bromonium ion could be solved by reaction medium engineering.

Whole-Cell Biotransformation of Penicillin G by a Three-Enzyme Co-expression System with Engineered Deacetoxycephalosporin C Synthase.

Deacetoxycephalosporin C synthase (DAOCS) catalyzes the transformation of penicillin G to phenylacetyl-7-aminodeacetoxycephalosporanic acid (G-7-ADCA) for which it depends on 2-oxoglutarate (2OG) as co-substrate. However, the low activity of DAOCS and the expense of 2OG restricts its practical applications in the production of G-7-ADCA. Herein, a rational design campaign was performed on a DAOCS from Streptomyces clavuligerus (scDAOCS) in the quest to construct novel expandases.

Wastewater-powered high-value chemical synthesis in a hybrid bioelectrochemical system.

A microbial electrochemical system could potentially be applied as a biosynthesis platform by extracting wastewater energy while converting it to value-added chemicals. However, the unfavorable thermodynamics and sluggish kinetics of whole-cell cathodic catalysis largely limit product diversity and value. Herein, we convert the cathodic reaction to enzymatic catalysis and develop a microbe-enzyme hybrid bioelectrochemical system (BES), where microbes release the electricity from wastewater (anode) to power enzymatic catalysis (cathode).

Valorization of Small Alkanes by Biocatalytic Oxyfunctionalization.

The oxidation of alkanes into valuable chemical products is a vital reaction in organic synthesis. This reaction, however, is challenging, owing to the inertness of C-H bonds. Transition metal catalysts for C-H functionalization are frequently explored.