Stable and Promiscuous Galactose Oxidases Engineered by Directed Evolution, Atomistic Design, and Ancestral Sequence Reconstruction.

Galactose oxidase (GOase) is a versatile biocatalyst with a wide range of potential applications, ranging from synthetic chemistry to bioelectrochemical devices. Previous GOase engineering by directed evolution generated the M-RQW mutant, with unprecedented new-to-nature oxidation activity at the C6-OH group of glucose, and a mutational backbone that helped to unlock its promiscuity toward other molecules, including secondary alcohols. In the current study, we have used the M-RQW mutant as a starting point to engineer a set of GOases that are very thermostable and that are easily produced at high titers in yeast, enzymes with latent activities applicable to sustainable chemistry.

Enzyme Benchmarking with Polyethylene Furanoate Soluble Scaffolds for Directed Evolution of PEFases.

Plastic waste is a major threat in our industrialized world and is driving research into bioplastics. The success of biobased polyethylene furanoate (PEF) as a viable alternative to polyethylene terephthalate (PET) of fossil origin will depend on designing effective enzymes to break it down, aiding its recycling. Here, a panel of fungal and bacterial cutinases were functionally expressed in a tandem yeast expression system based on and .

Directed evolution of the multicopper oxidase laccase for cell surface proximity labeling and electron microscopy.

Enzymes that oxidize aromatic substrates have shown utility in a range of cell-based technologies including live cell proximity labeling (PL) and electron microscopy (EM), but are associated with drawbacks such as the need for toxic HO. Here, we explore laccases as a novel enzyme class for PL and EM in mammalian cells. LaccID, generated via 11 rounds of directed evolution from an ancestral fungal laccase, catalyzes the one-electron oxidation of diverse aromatic substrates using O instead of toxic HO, and exhibits activity selective to the surface plasma membrane of both living and fixed cells.

Structural Insights and Reaction Profile of a New Unspecific Peroxygenase from Produced in a Tandem-Yeast Expression System.

Fungal unspecific peroxygenases (UPOs) are gaining momentum in synthetic chemistry. Of special interest is the UPO from (UPO), which shows an exclusive repertoire of oxyfunctionalizations, including the terminal hydroxylation of alkanes, the α-oxidation of fatty acids and the C-C cleavage of corticosteroids. However, the lack of heterologous expression systems to perform directed evolution has impeded its engineering for practical applications.

The colors of peroxygenase activity: Colorimetric high-throughput screening assays for directed evolution.

Fungal unspecific peroxygenases (UPOs) are arising as versatile biocatalysts for C-H oxyfunctionalization reactions. In recent years, several directed evolution studies have been conducted to design improved UPO variants. An essential part of this protein engineering strategy is the design of reliable colorimetric high-throughput screening (HTS) assays for mutant library exploration.

Insights into enhancing organ cell biofactories via hairy root protein profiling.

Recent advancements in plant biotechnology have highlighted the potential of hairy roots as a biotechnological platform, primarily due to their rapid growth and ability to produce specialized metabolites. This study aimed to delve deeper into hairy root development in and explore the optimization of genetic transformation for enhanced bioactive compound production. Previously established hairy root lines of were categorized based on their centelloside production capacity into HIGH, MID, or LOW groups.

Toward Kilogram-Scale Peroxygenase-Catalyzed Oxyfunctionalization of Cyclohexane.

Mol-scale oxyfunctionalization of cyclohexane to cyclohexanol/cyclohexanone (KA-oil) using an unspecific peroxygenase is reported. Using UPO from and simple HO as an oxidant, cyclohexanol concentrations of more than 300 mM (>60% yield) at attractive productivities (157 mM h, approx. 15 g L h) were achieved.

Robust Light Driven Enzymatic Oxyfunctionalization via Immobilization of Unspecific Peroxygenase.

Unspecific peroxygenases have attracted interest in synthetic chemistry, especially for the oxidative activation of C-H bonds, as they only require hydrogen peroxide (H O ) instead of a cofactor. Due to their instability in even small amounts of H O , different strategies like enzyme immobilization or in situ H O production have been developed to improve the stability of these enzymes. While most strategies have been studied separately, a combination of photocatalysis with immobilized enzymes was only recently reported.

Peroxygenase-Catalysed Selective Oxidation of Silanes to Silanols.

A peroxygenase-catalysed hydroxylation of organosilanes is reported. The recombinant peroxygenase from Agrocybe aegerita (AaeUPO) enabled efficient conversion of a broad range of silane starting materials in attractive productivities (up to 300 mM h ), catalyst performance (up to 84 s and more than 120 000 catalytic turnovers). Molecular modelling of the enzyme-substrate interaction puts a basis for the mechanistic understanding of AaeUPO selectivity.

Genetic approaches in improving biotechnological production of taxanes: An update.

Paclitaxel (PTX) and its derivatives are diterpene alkaloids widely used as chemotherapeutic agents in the treatment of various types of cancer. Due to the scarcity of PTX in nature, its production in cell cultures and plant organs is a major challenge for plant biotechnology. Although significant advances have been made in this field through the development of metabolic engineering and synthetic biology techniques, production levels remain insufficient to meet the current market demand for these powerful anticancer drugs.

Repertoire of Computationally Designed Peroxygenases for Enantiodivergent C-H Oxyfunctionalization Reactions.

The generation of enantiodivergent biocatalysts for C-H oxyfunctionalizations is ever more important in modern synthetic chemistry. Here, we have applied the FuncLib algorithm based on phylogenetic and Rosetta calculations to design a diverse repertoire of active, stable, and enantiodivergent fungal peroxygenases. 24 designs, each carrying 4-5 mutations in the catalytic core, were expressed functionally in yeast and benchmarked against characteristic model compounds.

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.

Designed High-Redox Potential Laccases Exhibit High Functional Diversity.

White-rot fungi secrete an impressive repertoire of high-redox potential laccases (HRPLs) and peroxidases for efficient oxidation and utilization of lignin. Laccases are attractive enzymes for the chemical industry due to their broad substrate range and low environmental impact. Since expression of functional recombinant HRPLs is challenging, however, iterative-directed evolution protocols have been applied to improve their expression, activity, and stability.

Using machine learning to link the influence of transferred genes to the hormone profile and morphological traits in hairy roots.

Hairy roots are made after the integration of a small set of genes from in the plant genome. Little is known about how this small set is linked to their hormone profile, which determines development, morphology, and levels of secondary metabolite production. We used hairy root line cultures to determine the putative links between the and gene expressions with morphological traits, a hormone profile, and centelloside production.

Biotic Elicitors in Adventitious and Hairy Root Cultures: A Review from 2010 to 2022.

One of the aims of plant in vitro culture is to produce secondary plant metabolites using plant cells and organ cultures, such as cell suspensions, adventitious, and hairy roots (among others). In cases where the biosynthesis of a compound in the plant is restricted to a specific organ, unorganized systems, such as plant cell cultures, are sometimes unsuitable for biosynthesis. Then, its production is based on the establishment of organ cultures such as roots or aerial shoots.

Efficient Base-Catalyzed Kemp Elimination in an Engineered Ancestral Enzyme.

The routine generation of enzymes with completely new active sites is a major unsolved problem in protein engineering. Advances in this field have thus far been modest, perhaps due, at least in part, to the widespread use of modern natural proteins as scaffolds for de novo engineering. Most modern proteins are highly evolved and specialized and, consequently, difficult to repurpose for completely new functionalities.

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 .

Surfing the wave of oxyfunctionalization chemistry by engineering fungal unspecific peroxygenases.

The selective insertion of oxygen into non-activated organic molecules has to date been considered of utmost importance to synthesize existing and next generation industrial chemicals or pharmaceuticals. In this respect, the minimal requirements and high activity of fungal unspecific peroxygenases (UPOs) situate them as the jewel in the crown of C-H oxyfunctionalization biocatalysts. Although their limited availability and development has hindered their incorporation into industry, the conjunction of directed evolution and computational design is approaching UPOs to practical applications.

Stable and Functionally Diverse Versatile Peroxidases Designed Directly from Sequences.

White-rot fungi secrete a repertoire of high-redox potential oxidoreductases to efficiently decompose lignin. Of these enzymes, versatile peroxidases (VPs) are the most promiscuous biocatalysts. VPs are attractive enzymes for research and industrial use but their recombinant production is extremely challenging.

A Peroxygenase-Alcohol Dehydrogenase Cascade Reaction to Transform Ethylbenzene Derivatives into Enantioenriched Phenylethanols.

In this study, we developed a new bienzymatic reaction to produce enantioenriched phenylethanols. In a first step, the recombinant, unspecific peroxygenase from Agrocybe aegerita (rAaeUPO) was used to oxidise ethylbenzene and its derivatives to the corresponding ketones (prochiral intermediates) followed by enantioselective reduction into the desired (R)- or (S)-phenylethanols using the (R)-selective alcohol dehydrogenase (ADH) from Lactobacillus kefir (LkADH) or the (S)-selective ADH from Rhodococcus ruber (ADH-A). In a one-pot two-step cascade, 11 ethylbenzene derivatives were converted into the corresponding chiral alcohols at acceptable yields and often excellent enantioselectivity.

Corrigendum: Mapping Potential Determinants of Peroxidative Activity in an Evolved Fungal Peroxygenase From .

[This corrects the article DOI: 10.3389/fbioe.2021.

Mapping Potential Determinants of Peroxidative Activity in an Evolved Fungal Peroxygenase from .

Fungal unspecific peroxygenases (UPOs) are hybrid biocatalysts with peroxygenative activity that insert oxygen into non-activated compounds, while also possessing convergent peroxidative activity for one electron oxidation reactions. In several ligninolytic peroxidases, the site of peroxidative activity is associated with an oxidizable aromatic residue at the protein surface that connects to the buried heme domain through a long-range electron transfer (LRET) pathway. However, the peroxidative activity of these enzymes may also be initiated at the heme access channel.

Ether Oxidation by an Evolved Fungal Heme-Peroxygenase: Insights into Substrate Recognition and Reactivity.

Ethers can be found in the environment as structural, active or even pollutant molecules, although their degradation is not efficient under environmental conditions. Fungal unspecific heme-peroxygenases (UPO were reported to degrade low-molecular-weight ethers through an HO-dependent oxidative cleavage mechanism. Here, we report the oxidation of a series of structurally related aromatic ethers, catalyzed by a laboratory-evolved UPO (PaDa-I) aimed at elucidating the factors influencing this unusual biochemical reaction.

Functional Expression of Two Unusual Acidic Peroxygenases from in Yeasts by Adopting Evolved Secretion Mutations.

Fungal unspecific peroxygenases (UPOs) are emergent biocatalysts that perform highly selective C-H oxyfunctionalizations of organic compounds, yet their heterologous production at high levels is required for their practical use in synthetic chemistry. Here, we achieved functional expression of two new unusual acidic peroxygenases from () (UPO) in yeasts and their production at a large scale in a bioreactor. Our strategy was based on adopting secretion mutations from an Agrocybe aegerita UPO mutant, the PaDa-I variant, designed by directed evolution for functional expression in yeast, which belongs to the same phylogenetic family as UPOs, long-type UPOs, and shares 65% sequence identity.