Structure-guided mining of stereoselective reductive aminases for biocatalytic stereodivergent synthesis of chiral piperidinamine and derivatives.

Chiral azacyclic amine derivatives occupy a vital role of nitrogen-containing compounds, due to serve as foundational motifs in numerous pharmaceuticals and bioactive substances. Novel complementary enantioselective reductive aminases IRED9 and IRED11 were unveiled through comprehensive gene mining from Streptomyces viridochromogenes and Micromonospora echinaurantiaca, respectively, which both demonstrated enantiomeric excess (ee) values and conversion ratios of up to 99 % towards N-Boc-3-pyridinone (NBPO) and cyclopropylamine. IRED9 exhibited the highest activity at pH 8.

Novel Approach for Efficient Separation of Primary Amines Using Supercritical Fluid Chromatography.

Efficient enantioselective separation is a critical process in pharmaceutical and chemical industries for the production of chiral compounds. Herein, we developed a novel approach for the efficient enantioselective separation of primary amines using supercritical fluid chromatography (SFC) with a commercially available SFC column, Cel1. The key factors of separation, including cosolvent ratios, total cosolvent percentages, and temperature, were systematically assessed in this study.

Enhanced stereodivergent evolution of carboxylesterase for efficient kinetic resolution of near-symmetric esters through machine learning.

Carboxylesterases serve as potent biocatalysts in the enantioselective synthesis of chiral carboxylic acids and esters. However, naturally occurring carboxylesterases exhibit limited enantioselectivity, particularly toward ethyl 3-cyclohexene-1-carboxylate (CHCE, S1), due to its nearly symmetric structure. While machine learning effectively expedites directed evolution, the lack of models for predicting the enantioselectivity for carboxylesterases has hindered progress, primarily due to challenges in obtaining high-quality training datasets.

Correlation Analysis of Characteristics of Intestinal Microbiota and Cytokine Levels in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome.

Objective: The aim of this study was to analyze the relationship between the characteristics of the intestinal microbiota and cytokine levels in individuals with different degrees of obstructive sleep apnea-hypopnea syndrome (OSAHS) as well as to investigate intestinal microbiota imbalances in patients with OSAHS and the associated mechanisms.

Methods: Based on their sleep apnea hypopnea index (AHI), a total of 37 adults were assigned to a control group, a mild OSAHS group, or a moderate-to-severe OSAHS group. Fecal samples were collected to characterize the intestinal microbiota using metagenomic next-generation sequencing (mNGS), while blood samples were collected to detect levels of interleukin-17a (IL-17a), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) in each group.

[Construction of a strain with multi-copy integration for enhanced bovine chymosin production by CRISPR/Cas9 and UV mutagenesis].

Bovine chymosin is an essential food enzyme widely used in cheese production in the dairy industry. This study used a codon-optimized prochymosin gene to construct an expression cassette for extracellular expression of bovine chymosin in . After integration of the prochymosin gene into the host cell genome, the single-copy integration strain KLUcym showed the clotting activity of 40 U/mL in a shake flask.

Biocatalytic Stereoselective Synthesis of Chiral Precursors for Liposoluble β Receptor Blocker Nebivolol.

Asymmetric reduction of 2-chloro-1-(6-fluorochroman-2-yl)ethan-1-one (NEB-7) into 2-chloro-1-(6-fluorochroman-2-yl)ethan-1-ol (NEB-8) is the crucial step for synthesis of liposoluble β receptor blocker nebivolol. Four efficient and stereoselective alcohol dehydrogenases were identified, enabling the stereoselective synthesis of all enantiomers of NEB-8 at a substrate loading of 137 g·L with ee values of >99% and high space-time yields. This study provides novel biocatalysts for the efficient synthesis of nebivolol precursors and uncovers the molecular basis for enantioselectivity manipulation by parametrization of Prelog's rule.

Clinical value of ultrasound-guided full-needle path anesthesia in transperineal prostate biopsy: An observational study.

Background: The pain sensation in a transperineal prostate biopsy was obvious. This study explored the clinical value of ultrasound-guided full-needle path anesthesia in transperineal prostate biopsy.

Methods: Two hundred patients who underwent ultrasound-guided transperineal prostate biopsy at our department were randomly divided into 2 groups.

Engineering of Methionine Adenosyltransferase toward Mitigated Product Inhibition for Efficient Production of -Adenosylmethionine.

-Adenosylmethionine (SAM) is a crucial metabolic intermediate playing irreplaceable roles in organismal activities. However, the synthesis of SAM by methionine adenosyltransferase (MAT) is hindered by low conversion due to severe product inhibition. Herein structure-guided semirational engineering was conducted on MAT from (MAT) to mitigate the product inhibitory effect.

Classification and functional origins of stereocomplementary alcohol dehydrogenases for asymmetric synthesis of chiral secondary alcohols: A review.

Alcohol dehydrogenases (ADHs) mediated biocatalytic asymmetric reduction of ketones have been widely applied in the synthesis of optically active secondary alcohols with highly reactive hydroxyl groups ligated to the stereogenic carbon and divided into (R)- and (S)-configurations. Stereocomplementary ADHs could be applied in the synthesis of both enantiomers and are increasingly accepted as the "first of choice" in green chemistry due to the high atomic economy, low environmental factor, 100 % theoretical yield, and high environmentally friendliness. Due to the equal importance of complementary alcohols, development of stereocomplementary ADHs draws increasing attention.

Photocatalytic regeneration of nicotinamide cofactor biomimetics drives biocatalytic reduction by Old Yellow enzymes.

A key approach in developing green chemistry involves converting solar energy into chemical energy of biomolecules through photocatalysis. Photocatalysis can facilitate the regeneration of nicotinamide cofactors during redox processes. Nicotinamide cofactor biomimetics (NCBs) are economical substitutes for natural cofactors.

Structure-Guided Evolution of Cyclohexanone Monooxygenase Toward Bulky Omeprazole Sulfide: Substrate Migration and Stereoselectivity Inversion.

Structure-guided engineering of a CHMO from Amycolatopsis methanolica (AmCHMO) was performed for asymmetric sulfoxidation activity and stereoselectivity toward omeprazole sulfide. Initially, combinatorial active-site saturation test (CASTing) and iteratively saturation mutagenesis (ISM) were performed on 5 residues at the "bottleneck" of substrate tunnel, and MT3 was successfully obtained with a specific activity of 46.19 U/g and R-stereoselectivity of 99 % toward OPS.

Engineering diaryl alcohol dehydrogenase KpADH reveals importance of retaining hydration shell in organic solvent tolerance.

Alcohol dehydrogenases (ADHs) are synthetically important biocatalysts for the asymmetric synthesis of chiral alcohols. The catalytic performance of ADHs in the presence of organic solvents is often important since most prochiral ketones are highly hydrophobic. Here, the organic solvent tolerance of KpADH from Kluyveromyces polyspora was semi-rationally evolved.

Mining and tailor-made engineering of a novel keto reductase for asymmetric synthesis of structurally hindered γ- and δ-lactones.

A novel carbonyl reductase from Hyphopichia burtoni (HbKR) was discovered by gene mining. HbKR is a NADPH-dependent dual function enzyme with reduction and oxidation activity belonging to SDR superfamily. HbKR strictly follows Prelog priority in the reduction of long-chain aliphatic keto acids/esters containing remote carbonyl groups, such as 4-oxodecanoic acid and 5-oxodecanoic acid, producing (S)-γ-decalactone and (S)-δ-decalactone in >99 % e.

A comparative study of two aldehyde dehydrogenases from sp.: the substrate spectrum and catalytic mechanism.

Biocatalytic oxidation is one of the most important and indispensable organic reactions for the development of green and sustainable biomanufacturing processes. NAD(P)-dependent aldehyde dehydrogenase (ALDH) catalyzes the oxidation of aldehydes to carboxylic acids. Here, two ALDHs, ALDH1 and ALDH2, were identified from sp.

Impact of sarcopenia on postoperative outcomes after hepatectomy in older patients with intrahepatic cholangiocarcinoma: A multicentre cohort study.

Background And Aims: Sarcopenia is associated with poor prognosis, but its role in older patients with intrahepatic cholangiocarcinoma (ICC) is unclear. We aimed to evaluate the impact of sarcopenia on the prognosis of older patients with ICC undergoing hepatectomy.

Methods: A total of 363 patients with ICC following hepatectomy from 2015 to 2021 were retrospectively reviewed at five institutions.

Engineering of Methionine Adenosyltransferase Reveals Key Roles of Electrostatic Interactions in Enhanced Catalytic Activity.

As an important dietary supplement, S-adenosylmethionine (SAM) is currently synthesized by methionine adenosyltransferase (MAT) using ATP and methionine as substrates. However, the activity of MAT is severely inhibited by product inhibition, which limits the industrial production of SAM. Here, MAT from Bacteroides fragilis (BfMAT), exhibiting relatively low product inhibition and moderate specific activity, was identified by gene mining.

Engineering Glucose Dehydrogenase to Favor Totally Synthetic Biomimetic Cofactors Containing Carboxyl Group.

The utilization of unnatural nicotinamide cofactors for reactions catalyzed by oxidoreductases has gained increasing interest. Totally synthetic nicotinamide cofactor biomimetics (NCBs) are cost-effective and convenient to synthesize. Thus, it has become increasingly important to develop enzymes that accept NCBs.

Membrane fusion, potential threats, and natural antiviral drugs of pseudorabies virus.

Pseudorabies virus (PrV) can infect several animals and causes severe economic losses in the swine industry. Recently, human encephalitis or endophthalmitis caused by PrV infection has been frequently reported in China. Thus, PrV can infect animals and is becoming a potential threat to human health.

Effects of obesity on short-term mortality in patients with acute heart failure under different nutritional status.

Background: Increased body mass index (BMI) is associated with better survival in patients with acute heart failure (AHF), which is a paradoxical phenomenon. However, it is unclear whether different nutritional status affects this association.

Methods: 1325 patients with AHF from the Medical Information Mart for Intensive Care III database were retrospectively included.

Efficient production of hyaluronic acid by Streptococcus zooepidemicus using two-stage semi-continuous fermentation.

Hyaluronic acid is a kind of mucopolysaccharide that has wide applications in cosmetics, health food, and orthopedics. Using Streptococcus zooepidemicus ATCC 39920 as parent, a beneficial mutant SZ07 was obtained by UV mutagenesis, giving 1.42 g/L hyaluronic acid in shake flasks.

Engineering the Thermostability of a d-Carbamoylase Based on Ancestral Sequence Reconstruction for the Efficient Synthesis of d-Tryptophan.

Employing ancestral sequence reconstruction and consensus sequence analysis, the thermostability of a novel d-carbamoylase derived from (HyuC) was engineered through greedy-oriented iterative combinatorial mutagenesis. A mutant S202P/E208D/R277L (M4Th3) was obtained with significantly elevated thermostability. M4Th3 has a half-life of 36.

Self-Sufficient In Vitro Multi-Enzyme Cascade for Efficient Synthesis of Danshensu from l-DOPA.

Danshensu (DSS), a traditional Chinese medicine, is widely used for the treatment of cardiovascular and cancer diseases. Here, a one-pot multi-enzyme cascade pathway was designed for DSS synthesis from l-DOPA using tyrosine aminotransferase from (TyrB) and d-isomer-specific 2-hydroxyacid dehydrogenase from (D2-HDH). Glutamate dehydrogenase from (gluD) was also introduced for a self-sufficient system of α-ketoglutaric acid and NADH.

Engineering of a Baeyer-Villiger monooxygenase reveals key residues for the asymmetric oxidation of omeprazole sulfide.

The structure-guided engineering of a BVMO from (BVMO) was performed for its asymmetric sulfoxidation activity toward omeprazole sulfide. Based on the structural model of BVMO, key residues that line the substrate entrance tunnel and the binding pocket were identified, and variants were interrogated with sulfides of varied sizes. The best mutant MT2 (F442A/R337P) was obtained with a specific activity of 2.

Directed reconstruction of a novel ancestral alcohol dehydrogenase featuring shifted pH-profile, enhanced thermostability and expanded substrate spectrum.

Ancestral enzymes are promising for industrial biotechnology due to high stability and catalytic promiscuity. An effective protocol was developed for the directed resurrection of ancestral enzymes. Employing genome mining with diaryl alcohol dehydrogenase KpADH as the probe, descendant enzymes D10 and D11 were firstly identified.

A multi-omic approach reveals utility of CD45 expression in prognosis and novel target discovery.

CD45, the leukocyte common antigen, is expressed on almost all cells of the immunological and hematological systems. CD45 expression is related to a variety of diseases, including leukemia and lymphoma. In this study, we analyzed the expression level of CD45 across cancers and evaluated the relationship between its expression and patient prognosis.