Ribonucleotide Reductases: Structure, Chemistry, and Metabolism Suggest New Therapeutic Targets.

Ribonucleotide reductases (RNRs) catalyze the de novo conversion of nucleotides to deoxynucleotides in all organisms, controlling their relative ratios and abundance. In doing so, they play an important role in fidelity of DNA replication and repair. RNRs' central role in nucleic acid metabolism has resulted in five therapeutics that inhibit human RNRs. In this review, we discuss the structural, dynamic, and mechanistic aspects of RNR activity and regulation, primarily for the human and Escherichia coli class Ia enzymes. The unusual radical-based organic chemistry of nucleotide reduction, the inorganic chemistry of the essential metallo-cofactor biosynthesis/maintenance, the transport of a radical over a long distance, and the dynamics of subunit interactions all present distinct entry points toward RNR inhibition that are relevant for drug discovery. We describe the current mechanistic understanding of small molecules that target different elements of RNR function, including downstream pathways that lead to cell cytotoxicity. We conclude by summarizing novel and emergent RNR targeting motifs for cancer and antibiotic therapeutics.

Oligomeric interactions maintain active-site structure in a noncooperative enzyme family.

The evolutionary benefit accounting for widespread conservation of oligomeric structures in proteins lacking evidence of intersubunit cooperativity remains unclear. Here, crystal and cryo-EM structures, and enzymological data, demonstrate that a conserved tetramer interface maintains the active-site structure in one such class of proteins, the short-chain dehydrogenase/reductase (SDR) superfamily. Phylogenetic comparisons support a significantly longer polypeptide being required to maintain an equivalent active-site structure in the context of a single subunit. Oligomerization therefore enhances evolutionary fitness by reducing the metabolic cost of enzyme biosynthesis. The large surface area of the structure-stabilizing oligomeric interface yields a synergistic gain in fitness by increasing tolerance to activity-enhancing yet destabilizing mutations. We demonstrate that two paralogous SDR superfamily enzymes with different specificities can form mixed heterotetramers that combine their individual enzymological properties. This suggests that oligomerization can also diversify the functions generated by a given metabolic investment, enhancing the fitness advantage provided by this architectural strategy.

Specific residues and conformational plasticity define the substrate specificity of short-chain dehydrogenases/reductases.

Short-chain dehydrogenases/reductases (SDRs) are one of the most prevalent enzyme families distributed among the sequenced microorganisms. Despite the presence of a conserved catalytic tetrad and high structural similarity, these enzymes exhibit different substrate specificities. The insufficient knowledge regarding the amino acids underlying substrate specificity hinders the understanding of the SDRs' roles in diverse and significant biological processes. Here, we performed bioinformatic analysis, molecular modeling, and mutagenesis studies to identify the key residues that regulate the substrate specificities of two homologous microbial SDRs (i.e., DesE and KduD). Further, we investigated the impact of altering the physicochemical properties of these amino acids on enzyme activity. Interestingly, molecular dynamics simulations also suggest a critical role of enzyme conformational flexibility in substrate recognition and catalysis. Overall, our findings improve the understanding of microbial SDR substrate specificity and shed light on future rational design of more efficient and effective biocatalysts.

Molecular insights into OPR gene family in Saccharum identified a ScOPR2 gene could enhance plant disease resistance.

12-Oxo-phytodienoic acid reductases (OPRs) perform vital functions in plants. However, few studies have been reported in sugarcane (Saccharum spp.), and it is of great significance to systematically investigates it in sugarcane. Here, 61 ShOPRs, 32 SsOPRs, and 36 SoOPRs were identified from R570 (Saccharum spp. hybrid cultivar R570), AP85-441 (Saccharum spontaneum), and LA-purple (Saccharum officinarum), respectively. These OPRs were phylogenetically classified into four groups, with close genes similar structures. During evolution, OPR gene family was mainly expanded via whole-genome duplications/segmental events and predominantly underwent purifying selection, while sugarcane OPR genes may function differently in response to various stresses. Further, ScOPR2, a tissue-specific OPR, which was localized in cytoplasm and cell membrane and actively response to salicylic acid (SA), methyl jasmonate, and smut pathogen (Sporisorium scitamineum) stresses, was cloned from sugarcane. In addition, both its transient overexpression and stable overexpression enhanced the resistance of transgenic plants to pathogen infection, most probably through activating pathogen-associated molecular pattern/pattern-recognition receptor-triggered immunity, producing reactive oxygen species, and initiating mitogen-activated protein kinase cascade. Subsequently, the transmission of SA and hypersensitive reaction were triggered, which stimulated the transcription of defense-related genes. These findings provide insights into the function of ScOPR2 gene for disease resistance.

Gene discovery and virus-induced gene silencing reveal branched pathways to major classes of bioactive diterpenoids in Euphorbia peplus.

Most macro- and polycyclic Euphorbiaceae diterpenoids derive from the common C20 precursor casbene. While the biosynthetic pathway from casbene to the lathyrane jolkinol C is characterized, pathways to other more complex classes of bioactive diterpenoids remain to be elucidated. A metabolomics-guided transcriptomic approach and a genomics approach that led to the discovery of two casbene-derived diterpenoid gene clusters yielded a total of 68 candidate genes that were transiently expressed in Nicotiana benthamiana for activity toward jolkinol C and other lathyranes. We report two short-chain dehydrogenases/reductases (SDRs), identified by RNA sequencing to be highly expressed in Euphorbia peplus latex. One of these, EpSDR-5, is a C3-ketoreductase, converting jolkinol C to the lathyrane jolkinol E. Gene function of EpSDR-5 was further confirmed by heterologous expression in Saccharomyces cerevisiae. To investigate the in vivo role of EpSDR-5, we established virus-induced gene silencing (VIGS) in E. peplus, resulting in a significant reduction in jatrophanes and a corresponding increase in ingenanes. VIGS of Casbene Synthase results in a major reduction in both jatrophanes and ingenanes, the two most abundant classes of E. peplus diterpenoids. VIGS of CYP71D365 had a similar effect, consistent with the previously determined role of this gene in the pathway to jolkinol C. These results point to jolkinol C being a branch point intermediate in the pathways to ingenanes and jatrophanes with EpSDR-5 responsible for the first step from jolkinol C to jatrophane production.

Methionine oxidation in bacteria: A reversible post-translational modification.

Methionine is a sulfur-containing residue found in most proteins which are particularly susceptible to oxidation. Although methionine oxidation causes protein damage, it can in some cases activate protein function. Enzymatic systems reducing oxidized methionine have evolved in most bacterial species and methionine oxidation proves to be a reversible post-translational modification regulating protein activity. In this review, we inspect recent examples of methionine oxidation provoking protein loss and gain of function. We further speculate on the role of methionine oxidation as a multilayer endogenous antioxidant system and consider its potential consequences for bacterial virulence.

Mining and functional characterization of NADPH-cytochrome P450 reductases of the DNJ biosynthetic pathway in mulberry leaves.

BACKGROUND: 1-Deoxynojirimycin (DNJ), the main active ingredient in mulberry leaves, with wide applications in the medicine and food industries due to its significant functions in lowering blood sugar, and lipids, and combating viral infections. Cytochrome P450 is a key enzyme for DNJ biosynthesis, its activity depends on the electron supply of NADPH-cytochrome P450 reductases (CPRs). However, the gene for MaCPRs in mulberry leaves remains unknown. RESULTS: In this study, we successfully cloned and functionally characterized two key genes, MaCPR1 and MaCPR2, based on the transcriptional profile of mulberry leaves. The MaCPR1 gene comprised 2064 bp, with its open reading frame (ORF) encoding 687 amino acids. The MaCPR2 gene comprised 2148 bp, and its ORF encoding 715 amino acids. The phylogenetic tree indicates that MaCPR1 and MaCPR2 belong to Class I and Class II, respectively. In vitro, we found that the recombinant enzymes MaCPR2 protein could reduce cytochrome c and ferricyanide using NADPH as an electron donor, while MaCPR1 did not. In yeast, heterologous co-expression indicates that MaCPR2 delivers electrons to MaC3'H hydroxylase, a key enzyme catalyzing the production of chlorogenic acid from 3-O-p-coumaroylquinic acid. CONCLUSIONS: These findings highlight the orchestration of hydroxylation process mediated by MaCPR2 during the biosynthesis of secondary metabolite biosynthesis in mulberry leaves. These results provided a foundational understanding for fully elucidating the DNJ biosynthetic pathway within mulberry leaves.

Bio-electrocatalytic alkene reduction using ene-reductases with methyl viologen as electron mediator.

Asymmetric hydrogenation of alkene moieties is important for the synthesis of chiral molecules, but achieving high stereoselectivity remains a challenge. Biocatalysis using ene-reductases (EReds) offers a viable solution. However, the need for NAD(P)H cofactors limits large-scale applications. Here, we explored an electrochemical alternative for recycling flavin-containing EReds using methyl viologen as a mediator. For this, we built a bio-electrocatalytic setup with an H-type glass reactor cell, proton exchange membrane, and carbon cloth electrode. Experimental results confirm the mediator's electrochemical reduction and enzymatic consumption. Optimization showed increased product concentration at longer reaction times with better reproducibility within 4-6 h. We tested two enzymes, Pentaerythritol Tetranitrate Reductase (PETNR) and the Thermostable Old Yellow Enzyme (TOYE), using different alkene substrates. TOYE showed higher productivity for the reduction of 2-cyclohexen-1-one (1.20 mM h-1), 2-methyl-2-cyclohexen-1-one (1.40 mM h-1) and 2-methyl-2-pentanal (0.40 mM h-1), with enantiomeric excesses ranging from 11% to 99%. PETNR outperformed TOYE in terms of enantioselectivity for the reduction of 2-methyl-2-pentanal (ee 59±7% (S)). Notably, TOYE achieved promising results also in reducing ketoisophorone, a challenging substrate, with similar enantiomeric excess compared to published values using NADH.

A High-Throughput Visual Screen for the Directed Evolution of C ß -stereoselectivity of L-threonine Aldolase.

L-Threonine aldolase (L-TA) is a pyridoxal phosphate-dependent enzyme that catalyzes the reversible condensation of glycine and aldehydes to form ß-hydroxy-α-amino acids. The combination of directed evolution and efficient high-throughput screening methods is an effective strategy for enhancing the enzyme's catalytic performance. However, few feasible high-throughput methods exist for engineering the Cß-stereoselectivity of L-TAs. Here, we present a novel method of screening for variants with improved Cß-stereoselectivity; this method couples an L-threo-phenylserine dehydrogenase, which catalyzes the specific oxidation of L-threo-4-methylsulfonylphenylserine (L-threo-MTPS), with the concurrent synthesis of NADPH, which is easily detectable via 340-nm UV absorption. This enables the visual detection of L-threo-MTPS produced by L-TA through the measurement of generated NADPH. Using this method, we discover an L-TA variant with significantly higher diastereoselectivity, increasing from 0.98% de (for the wild-type) to 71.9% de.

Metabolic engineering of Escherichia coli for high-level production of benzyl acetate from glucose.

BACKGROUND: Benzyl acetate is an aromatic ester with a jasmine scent. It was discovered in plants and has broad applications in food, cosmetic, and pharmaceutical industries. Its current production predominantly relies on chemical synthesis. In this study, Escherichia coli was engineered to produce benzyl acetate. RESULTS: Two biosynthetic routes based on the CoA-dependent ß-oxidation pathway were constructed in E. coli for benzyl acetate production. In route I, benzoic acid pathway was extended to produce benzyl alcohol by combining carboxylic acid reductase and endogenous dehydrogenases and/or aldo-keto reductases in E. coli. Benzyl alcohol was then condensed with acetyl-CoA by the alcohol acetyltransferase ATF1 from yeast to form benzyl acetate. In route II, a plant CoA-dependent ß-oxidation pathway via benzoyl-CoA was assessed for benzyl alcohol and benzyl acetate production in E. coli. The overexpression of the phosphotransacetylase from Clostridium kluyveri (CkPta) further improved benzyl acetate production in E. coli. Two-phase extractive fermentation in situ was adopted and optimized for benzyl acetate production in a shake flask. The most optimal strain produced 3.0 ± 0.2 g/L benzyl acetate in 48 h by shake-flask fermentation. CONCLUSIONS: We were able to establish the whole pathway for benzyl acetate based on the CoA-dependent ß-oxidation in single strain for the first time. The highest titer for benzyl acetate produced from glucose by E. coli is reported. Moreover, cinnamyl acetate production as an unwanted by-product was very low. Results provided novel information regarding the engineering benzyl acetate production in microorganisms.

Unveiling the biointerfaces characteristics and removal pathways of Cr(â ¥) in Bacillus cereus FNXJ1-2-3 for the Cr(â ¥)-to-Cr(0) conversion.

Although less toxic than hexavalent chromium, Cr (Ⅲ) species still pose a threat to human health. The Cr (Ⅵ) should be converted to Cr (0) instead of Cr (Ⅲ), which is still involved in biological detoxification filed. Herein, for the first time, it was found that Cr(Ⅵ) can be reduced into Cr(0) by Bacillus cereus FNXJ1-2-3, a way to completely harmless treatment of Cr(Ⅵ). The bacterial strain exhibited excellent performance in the reduction, sorption, and accumulation of Cr(Ⅵ) and Cr (Ⅲ). XPS etching characterization inferred that the transformation of Cr(Ⅵ) into Cr(0) followed a reduction pathway of Cr(Ⅵ)→Cr (Ⅲ)→metallic Cr(0), in which at least two secretory chromium reductases (ECrⅥ→Ⅲ and ECrⅢ→0) worked. Under the optimum condition, the yield ratio of Cr(0)/Cr (Ⅲ) reached 33.90%. In addition, the interfacial interactions, ion channels, chromium reductases, and external electron donors also contributed to the Cr(Ⅵ)/Cr(0) transformation. Findings of this study indicate that Bacillus cereus FNXJ1-2-3 is a promising bioremediation agent for Cr(Ⅵ) pollution control.

Time-course atherogenic blood lipid response to statin discontinuation in dyslipidemic adults.

BACKGROUND AND AIMS: Half of dyslipidemic patients sometimes discontinue statin medication. It is unclear if blood atherogenic risk increases right after statin discontinuation or if there is a lingering protective effect. We sought to determine if a legacy effect prevented blood lipid increases during the first stages of statin cessation. METHODS AND RESULTS: Atherogenic blood lipid profile was measured in 10 overweight (BMI 31 ± 3 kg m-2) middle-aged males (62 ± 7 years old), statin users, while fasted and postprandially. Trials were conducted before (i.e., Day 0) and after 4, 7, 15, and 30 days of statin withdrawal and 20 days after statins reloading (Day 50). Four days after statin discontinuation, blood fasting LDL-c, total cholesterol (CHOL), and triglyceride (TG) concentrations increased by 30%, 18%, and 17%, respectively (P < 0.05). The increases in LDL-c, CHOL, and TG peaked after 7-15 days at 79%, 48%, and 34% of basal levels (P < 0.001), respectively. There were no significant correlations between the increases in blood lipids and the dose or years under statin treatment (P = 0.156-0.575). Twenty days after resuming statins, blood LDL-c (2.79 ± 1.06 vs 2.20 ± 0.50 mmol L-1; P = 0.568), CHOL (4.85 ± 1.41 vs 4.25 ± 0.83 mmol L-1; P = 0.747), and TG (1.47 ± 0.60 vs 1.50 ± 0.68 mmol L-1; P = 0.782), returned to basal levels. CONCLUSIONS: Our data does not support a statin lingering/legacy effect in blood lipids since they dangerously increased after only 4 days of statin withdrawal in every patient, regardless of dose and years under treatment. Reloading statins restored blood lipids, evidencing a reproducible biological effect at the whole-body level.

The Impact of Long-Term Hypoxia on the Antioxidant Defense System in the Siberian Frog Rana amurensis.

The Siberian frog Rana amurensis has a uniquely high tolerance to hypoxia among amphibians, as it is able to withstand several months underwater with almost no oxygen (0.2 mg/liter) vs. several days for other studied species. Since it was hypothesized that hypoxia actives the antioxidant defense system in hypoxia-tolerant animals, one would expect similar response in R. amurensis. Here, we studied the effect of hypoxia in the Siberian frog based on the transcriptomic data, activities of antioxidant enzyme, and content of low-molecular-weight antioxidants. Exposure to hypoxia upregulated expression of three relevant transcripts (catalase in the brain and two aldo-keto reductases in the liver). The activities of peroxidase in the blood and catalase in the liver were significantly increased, while the activity of glutathione S-transferase in the liver was reduced. The content of low-molecular-weight antioxidants (thiols and ascorbate) in the heart and liver was unaffected. In general, only a few components of the antioxidant defense system were affected by hypoxia, while most remained unchanged. Comparison to other hypoxia-tolerant species suggests species-specific adaptations to hypoxia-related ROS stress.

Nitrogen-Centered Radicals Derived from Azidonucleosides.

Azido-modified nucleosides have been extensively explored as substrates for click chemistry and the metabolic labeling of DNA and RNA. These compounds are also of interest as precursors for further synthetic elaboration and as therapeutic agents. This review discusses the chemistry of azidonucleosides related to the generation of nitrogen-centered radicals (NCRs) from the azido groups that are selectively inserted into the nucleoside frame along with the subsequent chemistry and biological implications of NCRs. For instance, the critical role of the sulfinylimine radical generated during inhibition of ribonucleotide reductases by 2'-azido-2'-deoxy pyrimidine nucleotides as well as the NCRs generated from azidonucleosides by radiation-produced (prehydrated and aqueous) electrons are discussed. Regio and stereoselectivity of incorporation of an azido group ("radical arm") into the frame of nucleoside and selective generation of NCRs under reductive conditions, which often produce the same radical species that are observed upon ionization events due to radiation and/or other oxidative conditions that are emphasized. NCRs generated from nucleoside-modified precursors other than azidonucleosides are also discussed but only with the direct relation to the same/similar NCRs derived from azidonucleosides.

Cancer to Cataracts: The Mechanistic Impact of Aldo-Keto Reductases in Chronic Diseases.

Aldo-keto reductases (AKRs) are a superfamily of promiscuous enzymes that have been chiseled by evolution to act as catalysts for numerous regulatory pathways in humans. However, they have not lost their promiscuity in the process, essentially making them a double-edged sword. The superfamily is involved in multiple metabolic pathways and are linked to chronic diseases such as cataracts, diabetes, and various cancers. Unlike other detoxifying enzymes such as cytochrome P450s (CYP450s), short-chain dehydrogenases (SDRs), and medium-chain dehydrogenases (MDRs), that participate in essential pathways, AKRs are more widely distributed and have members with interchangeable functions. Moreover, their promiscuity is ubiquitous across all species and participates in the resistance of pathogenic microbes. Moreover, the introduction of synthetic substrates, such as synthetic molecules and processed foods, results in unwanted "toxification" due to enzyme promiscuity, leading to chronic diseases.

BioLindlar Catalyst: Ene-Reductase-Promoted Selective Bioreduction of Cyanoalkynes to Give (Z)-Cyanoalkenes.

The direct synthesis of alkenes from alkynes usually requires the use of transition-metal catalysts. Unfortunately, efficient biocatalytic alternatives for this transformation have yet to be discovered. Herein, the selective bioreduction of electron-deficient alkynes to alkenes catalysed by ene-reductases (EREDs) is described. Alkynes bearing ketone, aldehyde, ester, and nitrile moieties have been effectively reduced with excellent conversions and stereoselectivities, observing clear trends for the E/Z ratios depending on the nature of the electron-withdrawing group. In the case of cyanoalkynes, (Z)-alkenes were obtained as the major product, and the reaction scope was expanded to a wide variety of aromatic substrates (up to >99 % conversion, and Z/E stereoselectivities of up to >99/1). Other alkynes containing aldehyde, ketone, or ester functionalities also proved to be excellent substrates, and interestingly gave the corresponding (E)-alkenes. Preparative biotransformations were performed on a 0.4 mmol scale, producing the desired (Z)-cyanoalkenes with good to excellent isolated yields (63-97 %). This novel reactivity has been rationalised through molecular docking by predicting the binding poses of key molecules in the ERED-pu-0006 active site.

One-Pot Multienzyme Cascades for Stereodivergent Synthesis of Tetrahydroquinolines.

The tetrahydroquinoline (THQ) framework is commonly found in natural products and pharmaceutically relevant molecules. Apart from the use of transition metal catalysts and chiral phosphoric acids, the chiral 2-substituted 1,2,3,4-THQs are synthesized using amine oxidase biocatalysts. However, the use of imine reductases (IREDs) in their asymmetric synthesis remained unexplored. In the current work, IREDs are employed in telescopic multienzyme cascades to catalyze the intramolecular reductive amination leading to chiral 2-alkyl and 2-aryl substituted-1,2,3,4-tetrahydroquinolines starting from inexpensive nitroalkenones. The cascades containing NtDBR (an ene reductase), NfsB (a nitro reductase) with either Na2S2O4 or V2O5, various IREDs, and glucose dehydrogenase (for NADPH regeneration) are used to synthesize a broad range of (R)/(S)-2-alkyl-substituted (THQs) (26 examples) with high yield (up to 93%) and excellent ee (up to 99%) in one-pot. The method further facilitates the one-pot biocatalytic synthesis of chiral 2-aryl substituted THQs (26 examples) from amino chalcones. Lastly, the asymmetric synthesis of several (R)- and (S)-THQ based intermediates of Hancock alkaloids showed the practical application of the newly developed biocatalytic cascades.

Synthesis and Structural Characterization of a Non-Heme Iron Hyponitrite Complex.

Flavodiiron NO reductases (FNORs) are important enzymes in microbial pathogenesis, as they equip microbes with resistance to the human immune defense agent nitric oxide (NO). Despite much efforts, intermediates that would provide insight into how the non-heme diiron active sites of FNORs reduce NO to N2O could not be identified. Computations predict that iron-hyponitrite complexes are the key species, leading from NO to N2O. However, the coordination chemistry of non-heme iron centers with hyponitrite is largely unknown. In this study, we report the reactivity of two non-heme iron complexes with preformed hyponitrite. In the case of [Fe(TPA)(CH3CN)2](OTf)2, cleavage of hyponitrite and formation of an Fe2(NO)2 diamond core is observed. With less Lewis-acidic [Fe2(BMPA-PhO)2(OTf)2] (2), reaction with Na2N2O2 in polar aprotic solvent leads to the formation of a red complex, 3. X-ray crystallography shows that 3 is a tetranuclear iron-hyponitrite complex, [{Fe2(BMPA-PhO)2}2(µ-N2O2)](OTf)2, with a unique hyponitrite binding mode. This species provided the unique opportunity to us to study the interaction of hyponitrite with non-heme iron centers and the reactivity of the bound hyponitrite ligand. Here, either protonation or oxidation of 3 is found to induce N2O formation, supporting the hypothesis that hyponitrite is a viable intermediate in NO reduction.

Atroposelective Synthesis of Axial Biaryls by Dynamic Kinetic Resolution Using Engineered Imine Reductases.

Axially chiral biaryl compounds are ubiquitous scaffolds in natural products, bioactive molecules, chiral ligands and catalysts, but biocatalytic methods for their asymmetric synthesis are limited. Herein, we report a highly efficient biocatalytic route for the atroposelective synthesis of biaryls by dynamic kinetic resolution (DKR). This DKR approach features a transient six-membered aza-acetal-bridge-promoted racemization followed by an imine reductase (IRED)-catalyzed stereoselective reduction to construct the axial chirality under ambient conditions. Directed evolution of an IRED from Streptomyces sp. GF3546 provided a variant (S-IRED-Ss-M11) capable of catalyzing the DKR process to access a variety of biaryl aminoalcohols in high yields and excellent enantioselectivities (up to 98 % yield and >99 : 1 enantiomeric ratio). Molecular dynamics simulation studies on the S-IRED-Ss-M11 variant revealed the origin of its improved activity and atroposelectivity. By exploiting the substrate promiscuity of IREDs and the power of directed evolution, our work further extends the biocatalysts' toolbox to construct challenging axially chiral molecules.

Biocatalytic Desymmetrization for the Atroposelective Synthesis of Axially Chiral Biaryls Using an Engineered Imine Reductase.

The enzymatic atroposelective synthesis of biaryl compounds is relatively rare, despite considerable attention received by biocatalysis in academic and industrial sectors. Imine reductases (IREDs) are an important class of enzymes that have been applied in the asymmetric synthesis of chiral amine building blocks. In this work, two IREDs (IR140 and IR189) were identified to catalyze the efficient desymmetrization of biaryls utilizing various amine donors. Further protein engineering enabled the identification of variants (IR189 M8-M9 and IR189 M13-M14) that are able to catalyze the formation of both (R) and (S) atropisomers in excellent yields and atroposelectivities for up to 24 examples (up to 99% ee and yield). The absolute configuration and rotational barriers were confirmed, and the reactions were readily enlarged to allow isolation of the atropisomeric products in 99% ee and 82% isolated yields. The optically pure biaryl amines were further derivatized into various synthetically useful atropisomers. To shed light on the molecular recognition mechanisms, molecular dynamics (MD) simulations were performed, offering plausible explanations for the improved atroposelectivities and enzymatic activities. The current strategy expands the scope of IRED-catalyzed synthesis of axially chiral biaryl amines, contributing significantly to the field of atroposelective biocatalysis.