Screening of lipase TiL from Tilletia indica for chemo-enzymatic epoxidation of alkenes.

Lipase can mediate the chemo-enzymatic epoxidation of alkenes with the presence of free carboxylic acid and hydrogen peroxide. Four novel lipases with the abilities of chemo-enzymatic epoxidation were mined from the gene database. Lipase TiL originated from Tilletia indica was identified with significant activity on formation of methyl epoxystearate from methyl oleate.

(+)-3,6-Epoxymaaliane: A Novel Derivative of (+)-Bicyclogermacrene Oxidation Catalyzed by CYP450 BM3-139-3 and Its Variants.

(+)-Bicyclogermacrene is a sesquiterpene compound found in various plant essential oils and serves as a crucial precursor for multiple biologically active compounds. Many derivatives of (+)-bicyclogermacrene have been shown to exhibit valuable bioactivities. Cytochrome P450 BM3 from Bacillus megaterium can catalyze a variety of substrates and different types of oxidation reactions, making it become a powerful tool for oxidizing terpenes.

A High-Throughput Visual Screen for the Directed Evolution of Cβ-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 β-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 C-stereoselectivity of L-TAs.

Discovery and Engineering of a Bacterial (+)-Pulegone Reductase for Efficient (-)-Menthol Biosynthesis.

The biosynthesis of valuable plant-derived monoterpene (-)-menthol from readily available feedstocks (e. g., (-)-limonene) is of great significance because of the high market demand for this product.

Enhancing the biosynthesis of taxadien-5α-yl-acetate in Escherichia coli by combinatorial metabolic engineering approaches.

Biosynthesis of paclitaxel (Taxol™) is a hot topic with extensive and durable interests for decades. However, it is severely hindered due to the very low titers of intermediates. In this study, Escherichia coli was employed to de novo synthesize a key intermediate of paclitaxel, taxadien-5α-yl-acetate (T5OAc).

In silico analysis of the wheat BBX gene family and identification of candidate genes for seed dormancy and germination.

Background: B-box (BBX) proteins are a type of zinc finger proteins containing one or two B-box domains. They play important roles in development and diverse stress responses of plants, yet their roles in wheat remain unclear.

Results: In this study, 96 BBX genes were identified in the wheat genome and classified into five subfamilies.

Construction and optimization of a biocatalytic route for the synthesis of neomenthylamine from menthone.

(+)-Neomenthylamine is an important industrial precursor used to synthesize high value-added chemicals. Here, we report a novel biocatalytic route to synthesize (+)-neomenthylamine by amination of readily available (-)-menthone substrate using ω-transaminase. By screening a panel of ω-transaminases, an ω-transaminase from Vibrio fluvialis JS17 was identified with considerable amination activity to (-)-menthone, and then characterization of enzymatic properties was conducted for the enzyme.

Remodeling the Homologous Recombination Mechanism of for High-Level Biosynthesis of Squalene.

Squalene is a high-value antioxidant with many commercial applications. The use of microbial cell factories to produce squalene as an alternative to plant and animal extracts could meet increasing market demand. is an excellent host for squalene production due to its high levels of acetyl-CoA and a hydrophobic environment.

Machine-Learning-Guided Engineering of an NADH-Dependent 7β-Hydroxysteroid Dehydrogenase for Economic Synthesis of Ursodeoxycholic Acid.

Enzymatic synthesis of ursodeoxycholic acid (UDCA) catalyzed by an NADH-dependent 7β-hydroxysteroid dehydrogenase (7β-HSDH) is more economic compared with an NADPH-dependent 7β-HSDH when considering the much higher cost of NADP/NADPH than that of NAD/NADH. However, the poor catalytic performance of NADH-dependent 7β-HSDH significantly limits its practical applications. Herein, machine-learning-guided protein engineering was performed on an NADH-dependent 7β-HSDH from .

[Ultrasound-guided continuous fascia iliaca compartment block for perioperative pain management in elderly patients undergoing hip fracture surgery].

Objective: To study the effect of ultrasound-guided fascia iliaca compartment block on perioperative analgesia and postoperative complications in geriatric patients with hip fractures.

Methods: A total of 127 elderly patients undergoing hip fracture surgery from January 2021 to September 2021 were randomized to receive ultrasound-guided continuous fascia iliaca compartment block(group F) either intravenous analgesia control group(group C). There were 62 cases in group F, including 19 males and 43 females with an average age of (82.

Computational redesign of taxane-10β-hydroxylase for de novo biosynthesis of a key paclitaxel intermediate.

Paclitaxel (Taxol®) is the most popular anticancer diterpenoid predominantly present in Taxus. The core skeleton of paclitaxel is highly modified, but researches on the cytochrome P450s involved in post-modification process remain exceedingly limited. Herein, the taxane-10β-hydroxylase (T10βH) from Taxus cuspidata, which is the third post-modification enzyme that catalyzes the conversion of taxadiene-5α-yl-acetate (T5OAc) to taxadiene-5α-yl-acetoxy-10β-ol (T10OH), was investigated in Escherichia coli by combining computation-assisted protein engineering and metabolic engineering.

Improving solubility and copy number of taxadiene synthase to enhance the titer of taxadiene in .

Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel, but its microbial biosynthesis yield is very low. In this study, we employed as a microbial host to produce taxadiene. First, a "push-pull" strategy was adopted to increase taxadiene production by 234%.

Advances in T Cells Based on Inflammation in Metabolic Diseases.

With the increasing incidence of metabolic diseases year by year and their impact on the incidence of cardiovascular diseases, metabolic diseases have attracted great attention as a major health care problem, but there is still no effective treatment. Oxidative stress and inflammation are the main mechanisms leading to metabolic diseases. T cells are involved in the inflammatory response, which can also regulate the development of metabolic diseases, CD4+ T cells and CD8+ T cells are mainly responsible for the role.

First-principles investigation on the electronic structures of CdSe S and simulation of CdTe solar cell with a CdSe S window layer by SCAPS.

The short-circuit current density ( ) of CdTe solar cells both in the short and long wavelength regions can be effectively enhanced by using CdS/CdSe as the composite window layer. CdS/CdSe composite layers would interdiffuse to form the CdSe S ternary layer during the high temperature deposition process of CdTe films. In this paper, the electronic properties of CdSe S (0 ≤ ≤ 1) ternary alloys are investigated by first-principles calculation based on the density functional theory (DFT) and the performance of CdS/CdSe/CdTe devices are modeled by SCAPS to reveal why CdS/CdSe complex layers have good effects.

Regiospecific C-H amination of (-)-limonene into (-)-perillamine by multi-enzymatic cascade reactions.

Background: (-)-Limonene, one of cyclic monoterpenes, is an important renewable compound used widely as a key building block for the synthesis of new biologically active molecules and fine chemicals. (-)-Perillamine, as derived from (-)-limonene, is a highly useful synthon for constructing more complicated and functionally relevant chemicals.

Aim: We aimed to report a more sustainable and more efficient method for the regiospecific C-H amination of (-)-limonene into (-)-perillamine.

Building Flexible Modules for Bifunctionalizing -Octanol: The Byproduct of Oleic Acid Biorefinery.

Artificial biorefinery of oleic acid into 1,10-decanedioic acid represents a revolutionizing route to the sustainable production of chemically difficult-to-make bifunctional chemicals. However, the carbon atom economy is extremely low (56%) due to the formation of unifunctional -octanol. Here, we report a panel of recombinant modules for diverse bifunctionalization, where the desired genetic parts are well distributed into different modules that can be flexibly combined in a plug-and-play manner.

Effect of Algoplaque Hydrocolloid Dressing Combined with Nanosilver Antibacterial Gel under Predictive Nursing in the Treatment of Medical Device-Related Pressure Injury.

It was aimed at the clinical value of predictive nursing and Algoplaque hydrocolloid dressing (AHD) combined with nanosilver antibacterial gel in treating medical device-related pressure injury (MDRPI). 100 patients, who underwent surgery in Chongqing Qijiang District People's Hospital from February 2019 to February 2020, were selected as the research objects and were randomly divided into the experimental group (50 cases) and the control group (50 cases). For the characterization test, a nanosilver antibacterial gel was created first.

Enzymatic synthesis of high-titer nicotinamide mononucleotide with a new nicotinamide riboside kinase and an efficient ATP regeneration system.

Background: β-Nicotinamide mononucleotide (NMN) is the direct precursor of nicotinamide coenzymes such as NAD and NADP, which are widely applied in industrial biocatalysis especially involving cofactor-dependent oxidoreductases. Moreover, NMN is a promising candidate for medical uses since it is considered to be beneficial for improving health of aged people who usually suffer from an insufficient level of NAD. To date, various methods have been developed for the synthesis of NMN.

Carving the Active Site of CYP153A7 Monooxygenase for Improving Terminal Hydroxylation of Medium-Chain Fatty Acids.

The P450-mediated terminal hydroxylation of non-activated C-H bonds is a chemically challenging reaction. CYP153A7 monooxygenase, discovered in Sphingomonas sp. HXN200, belongs to the CYP153A subfamily and shows a pronounced terminal selectivity.

Volatile composition changes in lemon during fruit maturation by HS-SPME-GC-MS.

Background: Volatiles are determinants of fruit aroma and flavor characteristics and also provide valuable information for lemon as ingredient for the food and drinks industry. Volatiles in 'Eureka' lemon and 'Xiangshui' lemon pulps from 130 to 186 days after flowering were enriched by headspace-solid-phase microextraction (HS-SPME), and analyzed by gas chromatography-mass spectrometry (GC-MS).

Results: Seventy-seven volatiles of two lemon cultivars at the different ripening stages were identified and divided into six categories.

Removing the Obstacle to (-)-Menthol Biosynthesis by Building a Microbial Cell Factory of (+)-cis-Isopulegone from (-)-Limonene.

Microbial synthesis of plant-based (-)-menthol is of great interest because of its high demand (≈30 kiloton per year) as well as unique odor and cooling characteristics. However, this remains a great challenge due to the yet unfilled gap between (-)-limonene and (+)-cis-isopulegone. Herein, the first artificial and effective system was developed for (+)-cis-isopulegone biosynthesis from (-)-limonene by recruiting two bacterial enzymes to replace their inefficient counterparts from Mentha piperita, limonene-3-hydroxylase, and isopiperitenol dehydrogenase.

Discovery and Engineering of a Novel Baeyer-Villiger Monooxygenase with High Normal Regioselectivity.

Baeyer-Villiger monooxygenases (BVMOs) are remarkable biocatalysts for the Baeyer-Villiger oxidation of ketones to generate esters or lactones. The regioselectivity of BVMOs is essential for determining the ratio of the two regioisomeric products ("normal" and "abnormal") when catalyzing asymmetric ketone substrates. Starting from a known normal-preferring BVMO sequence from Pseudomonas putida KT2440 (PpBVMO), a novel BVMO from Gordonia sihwensis (GsBVMO) with higher normal regioselectivity (up to 97/3) was identified.

Color-dependent unidirectional scattering of a plasmonic heterodimer investigated by a dipole-dipole interference model.

In this paper, we employ an interference model of two separated electric dipoles to study the color-dependent unidirectional scattering of a plasmonic heterodimer consisting of a pair of gold and silver disks of the same size. The dipole moments in such a dipole-dipole interference model are numerically obtained by a multipole decomposition method. It shows that the power difference between the different scattering directions predicted by the dipole-dipole interference model agrees well with that calculated by the full wave simulation.