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1.
Front Immunol ; 15: 1398310, 2024.
Article in English | MEDLINE | ID: mdl-38835767

ABSTRACT

Background: Hydroxytryptophan (5-HTP) can regulate the synthesis of 5-Hydroxytryptamine (5-HT) and melatonin (MT). In a previous metabolome analysis, we found that 5-HTP is an effective ingredient in yeast culture for regulating rumen fermentation. However, research on the effect of this microbial product (5-HTP) as a functional feed additive in sheep production is still not well explained. Therefore, this study examined the effects of 5-HTP on sheep rumen function and growth performance using in vitro and in vivo models. Methods: A two-factor in vitro experiment involving different 5-HTP doses and fermentation times was conducted. Then, in the in vivo experiment, 10 sheep were divided into a control group which was fed a basal diet, and a 5-HTP group supplemented with 8 mg/kg 5-HTP for 60 days. Results: The results showed that 5-HTP supplementation had a significant effect on in vitro DMD, pH, NH3-N, acetic acid, propionic acid, and TVFA concentrations. 5-HTP altered rumen bacteria composition and diversity indices including Chao1, Shannon, and Simpson. Moreover, the in vivo study on sheep confirmed that supplementing with 8 mg/kg of 5-HTP improved rumen fermentation efficiency and microbial composition. This led to enhanced sheep growth performance and increased involvement in the tryptophan metabolic pathway, suggesting potential benefits. Conclusion: Dietary 5-HTP (8 mg/kg DM) improves sheep growth performance by enhancing ruminal functions, antioxidant capacity, and tryptophan metabolism. This study can provide a foundation for the development of 5-HTP as a functional feed additive in ruminants' production.


Subject(s)
5-Hydroxytryptophan , Animal Feed , Antioxidants , Dietary Supplements , Fermentation , Rumen , Tryptophan , Animals , Rumen/metabolism , Rumen/microbiology , Tryptophan/metabolism , 5-Hydroxytryptophan/pharmacology , Sheep , Antioxidants/pharmacology , Gastrointestinal Microbiome/drug effects , Diet/veterinary
2.
Heliyon ; 10(10): e31450, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38831823

ABSTRACT

Ethnopharmacological relevance: Tumour-derived extracellular vesicles (TEVs) have been confirmed to facilitate colorectal cancer (CRC) metastasis by remodelling the tumour microenvironment (TME). Drugs targeted TEVs is considered as a promising therapeutic strategy for cancer treatment. Traditional Chinese medicine (TCM) plays a vital role in improving the prognosis of CRC patients and eventually CRC patients with distant metastasis. Although the anti-tumour effects of active compounds from TCM prescriptions are observed widely, the molecular mechanisms remain unknown. Aim of the study: This study aims to investigate the effects of active compounds in our library of TCM on preventing CRC metastasis, and also explore the potential mechanisms from the perspective of TEVs. Materials and methods: The effects of active compounds on the proliferation of CRC cells were determined by CCK-8 assay. TEVs were extracted from MC38 cells by ultracentrifugation and characterized by electron microscopy, Nanosight NS300 and western blotting. The TEV particles were quantified by Nanosight NS300. The potential mechanism by which astragaloside IV (ASIV) reduced TEV secretion was determined by western blotting. RAW264.7 cells were cocultured with the conditioned medium (CM) of MC38 cells treated with or without ASIV, and the activation of tumour-associated macrophages (TAMs) was assessed by immunofluorescence and quantitative polymerase chain reaction (qPCR). The migration of CRC cells was measured by wound healing and Transwell assay. A spleen-to-liver metastasis model of colorectal cancer was used to confirm the efficiency of ASIV in vivo. Liver metastatic tumours of the mice were used for liver weight measures and H&E staining. Immunofluorescence was applied to observe the infiltration of TAMs, the expression of neutral sphingomyelinase 2 (nSMase2) and Rab27a. Results: By screening our TCM monomer library, we found that ASIV, which is mainly extracted from Radix Astragali, reduced the release of TEVs from CRC cells in a time- and concentration-dependent manner. Mechanistically, ASIV inhibited the production and secretion of TEVs by downregulating nSMase2 and Rab27a expression in CRC cells. CM from ASIV-treated CRC cells reshaped the polarization of TAMs by decreasing M2-type polarization, increasing M1-type polarization. Consequently, the repolarization of M2-type to M1-type macrophages led to reduced invasion and migration of CRC cells. Moreover, we confirmed that ASIV inhibited the liver metastasis of CRC, reduced M2-type macrophage infiltration and decreased the expression of nSMase2 and Rab27a in liver metastases. Conclusions: ASIV inhibited CRC metastasis by reducing EVs release and suppressing M2-type TAMs activation. All these findings reveal a new insight into the mechanisms of ASIV in preventing CRC progression and provide a promising approach for anti-tumour therapy.

3.
Chembiochem ; : e202400285, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38752893

ABSTRACT

ω-Transaminases (ω-TAs) are attractive biocatalysts asymmetrically catalyzing ketones to chiral amines. However, poor non-native catalytic activity and substrate promiscuity severely hamper its wide application in industrial production. Protein engineering efforts have generally focused on reshaping the substrate-binding pockets of ω-TAs. However, hotspots around the substrate tunnel as well as distant sites outside the pockets may also affect its activity. In this study, the ω-TA from Bacillus megaterium (BmeTA) was selected for engineering. The tunnel mutation Y164F synergy with distant mutation A245T which was acquired through a multiple sequence alignment showed improved soluble expression, a 3.7-fold higher specific activity and a 19.9-fold longer half-life at 45℃. Molecule Dynamics simulation explains the mechanism of improved catalytic activity, enhanced thermostability and improved soluble expression of BmeTAY164F/A245T(2M). Finally, the resting cells of 2M were used for biocatalytic processes. 450 mM of S-methoxyisopropylamine (S-MOIPA) was obtained with an ee value of 97.3% and a conversion rate of 90%, laying the foundation for its industrial production. Mutant 2M was also found to be more advantageous in catalyzing the transamination of various ketones. These results demonstrated that sites that are far away from the active center also play an important role in the redesign of ω-TAs.

4.
Mol Nutr Food Res ; : e2300917, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778506

ABSTRACT

SCOPE: High-fat diet induced circadian rhythm disorders (CRD) are associated with metabolic diseases. As the main functional bioactive component in oat, ß-glucan (GLU) can improve metabolic disorders, however its regulatory effect on CRD remains unclear. In this research, the effects of GLU on high-fat diet induced insulin resistance and its mechanisms are investigated, especially focusing on circadian rhythm-related process. METHODS AND RESULTS: Male C57BL/6 mice are fed a low fat diet, a high-fat diet (HFD), and HFD supplemented 3% GLU for 13 weeks. The results show that GLU treatment alleviates HFD-induced insulin resistance and intestinal barrier dysfunction in obese mice. The rhythmic expressions of circadian clock genes (Bmal1, Clock, and Cry1) in the colon impaired by HFD diet are also restored by GLU. Further analysis shows that GLU treatment restores the oscillatory nature of gut microbiome, which can enhance glucagon-like peptide (GLP-1) secretion via short-chain fatty acids (SCFAs) mediated activation of G protein-coupled receptors (GPCRs). Meanwhile, GLU consumption significantly relieves colonic inflammation and insulin resistance through modulating HDAC3/NF-κB signaling pathway. CONCLUSION: GLU can ameliorate insulin resistance due to its regulation of colonic circadian clock and gut microbiome.

5.
Sci Rep ; 14(1): 11794, 2024 05 23.
Article in English | MEDLINE | ID: mdl-38782963

ABSTRACT

We present the Manatee variational autoencoder model to predict transcription factor (TF) perturbation-induced transcriptomes. We demonstrate that the Manatee in silico perturbation analysis recapitulates target transcriptomic phenotypes in diverse cellular lineage transitions. We further propose the Manatee in silico screening analysis for prioritizing TF combinations targeting desired transcriptomic phenotypes.


Subject(s)
Transcription Factors , Transcriptome , Transcription Factors/metabolism , Transcription Factors/genetics , Humans , Gene Expression Profiling , Computer Simulation , Computational Biology/methods , Algorithms
6.
Invest Ophthalmol Vis Sci ; 65(5): 17, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38717424

ABSTRACT

Purpose: We aimed to identify structural differences in normal eyes, early age-related macular degeneration (AMD), and intermediate AMD eyes using optical coherence tomography (OCT) in a well-characterized, large cross-sectional cohort. Methods: Subjects ≥ 60 years with healthy normal eyes, as well as early or intermediate AMD were enrolled in the Alabama Study on Age-related Macular Degeneration 2 (ALSTAR2; NCT04112667). Using Spectralis HRA + OCT2, we obtained macular volumes for each participant. An auto-segmentation software was used to segment six layers and sublayers: photoreceptor inner and outer segments, subretinal drusenoid deposits (SDDs), retinal pigment epithelium + basal lamina (RPE + BL), drusen, and choroid. After manually refining the segmentations of all B-scans, mean thicknesses in whole, central, inner and outer rings of the ETDRS grid were calculated and compared among groups. Results: This study involved 502 patients, 252 were healthy, 147 had early AMD, and 103 had intermediate AMD eyes (per Age-Related Eye Disease Study [AREDS] 9-step). Intermediate AMD eyes exhibited thicker SDD and drusen, thinner photoreceptor inner segments, and RPE compared to healthy and early AMD eyes. They also had thicker photoreceptor outer segments than early AMD eyes. Early AMD eyes had thinner photoreceptor outer segments than normal eyes but a thicker choroid than intermediate AMD eyes. Using the Beckman scale, 42% of the eyes initially classified as early AMD shifted to intermediate AMD, making thickness differences for photoreceptor outer segments and choroid insignificant. Conclusions: With AMD stages, the most consistent structural differences involve appearance of drusen and SDD, followed by RPE + BL thickness, and then thickness of photoreceptor inner and outer segments. Structural changes in the transition from aging to intermediate AMD include alterations in the outer retinal bands, including the appearance of deposits on either side of the RPE.


Subject(s)
Choroid , Macular Degeneration , Retinal Drusen , Retinal Pigment Epithelium , Tomography, Optical Coherence , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Choroid/pathology , Choroid/diagnostic imaging , Cross-Sectional Studies , Macular Degeneration/diagnosis , Retinal Drusen/diagnosis , Retinal Photoreceptor Cell Outer Segment/pathology , Retinal Pigment Epithelium/pathology , Retinal Pigment Epithelium/diagnostic imaging , Tomography, Optical Coherence/methods , Visual Acuity/physiology
7.
J Ethnopharmacol ; 331: 118277, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38697407

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Chemotherapy tolerance weakened efficacy of chemotherapy drugs in the treating gastric cancer (GC). Banxiaxiexin decoction (BXXXD) was widely used in digestive diseases for thousands of years in Traditional Chinese medicine (TCM). In order to better treat GC, three other herbs were added to BXXXD to create a new prescription named Modified Banxiaxiexin decoction (MBXXXD). Although MBXXXD potentially treated GC by improving chemotherapy tolerance, the possible mechanisms were still unknown. AIM OF THE STUDY: To explore the therapeutic effect of MBXXXD on GC patients and explore the possible anti-cancer mechanism. MATERIALS AND METHODS: A randomized controlled trial (n = 146) was conducted to evaluate the clinical efficacy between MBXXXD + chemotherapy (n = 73) and placebo + chemotherapy (n = 73) in GC patients by testing overall survival, progression free survival, clinical symptoms, quality of life score, tumor markers, T cell subpopulation, and adverse reactions. Network pharmacology was conducted to discover the potential mechanism of MBXXXD in treating GC. Metabolic activity assay, cell clone colony formation and mitochondrial apoptosis were detected in human GC cell lines including AGS cell, KNM-45 cell and SGC7901 cell treated by MBXXXD. Multiple pathways including P53, AKT, IκB, P65, P38, ERK, JNK p-AKT, p-P65, p-P38, p-ERK and p-JNK in AGS cell, KNM-45 cell and SGC7901 cell treated by MBXXXD and GC patients treated by MBXXXD + chemotherapy were also detected. RESULTS: MBXXXD + chemotherapy promoted overall survival and progression free survival, improved clinical symptoms and quality of life score, increased T4 lymphocyte ratio and T8 lymphocyte ratio as well as T4/T8 lymphocyte ratio, and alleviated adverse reactions in GC patients. Network pharmacology predicted multiple targets and pathways of MBXXXD in treating GC including apoptosis, P53 pathway, AKT pathway, MAPK pathway. MBXXXD inhibited cell viability, decreased cell clone colony formation, and promoted mitochondrial apoptosis by producing reactive oxygen species (ROS), promoting mitochondrial permeability transition pore (MPTP) and the cleavage of pro-caspase-3 and pro-caspase-9, and decreasing mito-tracker red Chloromethyl-X-rosamine (CMXRos) in AGS cell, KNM-45 cell and SGC7901 cell. MBXXXD up-regulated the expression of P53 and IκB, and down-regulated the expression of p-AKT, p-P65, p-P38, p-ERK, p-JNK, AKT, P65, P38, ERK and JNK AGS cell, KNM-45 cell and SGC7901 cell treated by MBXXXD and GC patients treated by MBXXXD + chemotherapy. CONCLUSION: MBXXXD benefitted chemotherapy for GC by regulating multiple targets and pathways.


Subject(s)
Drugs, Chinese Herbal , Stomach Neoplasms , Humans , Stomach Neoplasms/drug therapy , Stomach Neoplasms/pathology , Female , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Middle Aged , Male , Cell Line, Tumor , Aged , Apoptosis/drug effects , Signal Transduction/drug effects , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Adult , Network Pharmacology
8.
Int J Biol Macromol ; 269(Pt 2): 132102, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729465

ABSTRACT

Optically pure 1,2,3,4-tetrahydroquinolines (THQs) represent a class of important motifs in many natural products and pharmaceutical agents. While recent advances on redox biocatalysis have demonstrated the great potential of amine oxidases, all the transformations focused on 2-substituted THQs. The corresponding biocatalytic method for the preparation of chiral 4-substituted THQs is still challenging due to the poor activity and stereoselectivity of the available enzyme. Herein, we developed a biocatalytic kinetic resolution approach for enantiodivergent synthesis of 4-phenyl- or alkyl-substituted THQs. Through structure-guided protein engineering of cyclohexylamine oxidase derived from Brevibacterium oxidans IH-35 A (CHAO), the variant of CHAO (Y215H/Y214S) displayed improved specific activity toward model substrate 4-phenyl substituted THQ (0.14 U/mg, 13-fold higher than wild-type CHAO) with superior (R)-stereoselectivity (E > 200). Molecular dynamics simulations show that CHAO Y215H/Y214S allows a suitable substrate positioning in the expanded binding pocket to be facilely accessed, enabling enhanced activity and stereoselectivity. Furthermore, a series of 4-alkyl-substituted THQs can be transformed by CHAO Y215H/Y214S, affording R-isomers with good yields (up to 50 %) and excellent enantioselectivity (up to ee > 99 %). Interestingly, the monoamine oxidase from Pseudomonas fluorescens Pf0-1 (PfMAO1) with opposite enantioselectivity was also mined. Together, this system enriches the kinetic resolution methods for the synthesis of chiral THQs.


Subject(s)
Quinolines , Kinetics , Stereoisomerism , Quinolines/chemistry , Biocatalysis , Brevibacterium/enzymology , Substrate Specificity , Molecular Dynamics Simulation , Monoamine Oxidase/metabolism , Monoamine Oxidase/chemistry
9.
Int J Biol Macromol ; 270(Pt 1): 132026, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38704074

ABSTRACT

Multiple phenolic substances have been shown to promote SIRT3 expression, however, few studies have focused on the effects of these phenolics on SIRT3 enzyme activity. This study constructed a variety of reaction systems to elucidate the mechanisms by which different polyphenols affect SIRT3 enzyme activity. The results showed that acP53317-320 was the most suitable substrate among the five acetylated peptide substrates (Kcat/Km = 74.85 ± 1.86 M-1•s-1). All the phenolic compounds involved in the experiment inhibited the enzymatic activity of SIRT3, and the lowest IC50 among them was quercetin (0.12 ± 0.01 mM) and the highest was piceatannol (1.29 ± 0.08 mM). Their inhibition types were mainly competitive and mixed. In addition, piceatannol was found to be a natural SIRT3 agonist by enzyme kinetic analysis and validation of deacetylation efficiency. This study will provide a useful reference for polyphenol modulation of SIRT3 dosage, as well as the development and application of polyphenol-based SIRT3 activators and agonists.


Subject(s)
Polyphenols , Sirtuin 3 , Sirtuin 3/metabolism , Polyphenols/pharmacology , Polyphenols/chemistry , Acetylation , Humans , Kinetics , Stilbenes/pharmacology , Stilbenes/chemistry
10.
Toxicol Lett ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38734219

ABSTRACT

Humantenmine, koumine, and gelsemine are three indole alkaloids found in the highly toxic plant Gelsemium. Humantenmine was the most toxic, followed by gelsemine and koumine. The aim of this study was to investigate and analyze the effects of these three substances on tissue distribution and toxicity in mice pretreated with the Cytochrome P450 3A4 (CYP3A4) inducer ketoconazole and the inhibitor rifampicin. The in vivo test results showed that the three alkaloids were absorbed rapidly and had the ability to penetrate the blood-brain barrier. At 5minutes after intraperitoneal injection, the three alkaloids were widely distributed in various tissues and organs, the spleen and pancreas were the most distributed, and the content of all tissues decreased significantly at 20minutes. Induction or inhibition of CYP3A4 in vivo can regulate the distribution and elimination effects of the three alkaloids in various tissues and organs. Additionally, induction of CYP3A4 can reduce the toxicity of humantenmine, and vice versa. Changes in CYP3A4 levels may account for the difference in toxicity of humantenmine. These findings provide a reliable and detailed dataset for drug interactions, tissue distribution, and toxicity studies of Gelsemium alkaloids.

11.
Small ; : e2400866, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38639306

ABSTRACT

The scarcity of Te hampers the widespread use of Bi2Te3-based thermoelectric modules. Here, the thermoelectric module potential of PbSe is investigated by improving its carrier mobility. Initially, large PbSe crystals are grown with the temperature gradient method to mitigate grain boundary effects on carrier transport. Subsequently, light doping with <1mole‰ halogens (Cl/Br/I) increases room-temperature carrier mobility to ~1600 cm2 V-1 s-1, achieved by reducing carrier concentration compared to traditional heavy doping. Crystal growth design and light doping enhance carrier mobility without affecting effective mass, resulting in a high power factor ~40 µW cm-1 K-2 in PbSe-Cl/Br/I crystals at 300 K. Additionally, Cl/Br/I doping reduces thermal conductivity and bipolar diffusion, leading to significantly lower thermal conductivity at high temperature. Enhanced carrier mobility and suppressed bipolar effect boost ZT values across the entire temperature range in n-type PbSe-Cl/Br/I crystals. Specifically, ZT values of PbSe-Br crystal reach ~0.6 at 300 K, ~1.2 at 773 K, and the average ZT (ZTave) reaches ~1.0 at 300-773 K. Ultimately, ~5.8% power generation efficiency in a PbSe single leg with a maximum temperature cooling difference of 40 K with 7-pair modules is achieved. These results indicate the potential for cost-effective and high-performance thermoelectric cooling modules based on PbSe.

12.
Osteoporos Int ; 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38625381

ABSTRACT

Osteoporosis-pseudoglioma syndrome (OPPG) and LRP5 high bone mass (LRP5-HBM) are two rare bone diseases with opposite clinical symptoms caused by loss-of-function and gain-of-function mutations in LRP5. Bisphosphonates are an effective treatment for OPPG patients. LRP5-HBM has a benign course, and age-related bone loss is found in one LRP5-HBM patient. PURPOSE: Low-density lipoprotein receptor-related protein 5 (LRP5) is involved in the canonical Wnt signaling pathway. The gain-of-function mutation leads to high bone mass (LRP5-HBM), while the loss-of-function mutation leads to osteoporosis-pseudoglioma syndrome (OPPG). In this study, the clinical manifestations, disease-causing mutations, treatment, and follow-up were summarized to improve the understanding of these two diseases. METHODS: Two OPPG patients and four LRP5-HBM patients were included in this study. The clinical characteristics, biochemical and radiological examinations, pathogenic mutations, and structural analysis were summarized. Furthermore, several patients were followed up to observe the treatment effect and disease progress. RESULTS: Congenital blindness, persistent bone pain, low bone mineral density (BMD), and multiple brittle fractures were the main clinical manifestations of OPPG. Complex heterozygous mutations were detected in two OPPG patients. The c.1455G > T mutation in exon 7 was first reported. During the follow-up, BMD of two patients was significantly improved after bisphosphonate treatment. On the contrary, typical clinical features of LRP5-HBM included extremely high BMD without fractures, torus palatinus and normal vision. X-ray showed diffuse osteosclerosis. Two heterozygous missense mutations were detected in four patients. In addition, age-related bone loss was found in one LRP5-HBM patient after 12-year of follow-up. CONCLUSION: This study deepened the understanding of the clinical characteristics, treatment, and follow-up of OPPG and LRP5-HBM; expanded the pathogenic gene spectrum of OPPG; and confirmed that bisphosphonates were effective for OPPG. Additionally, it was found that Ala242Thr mutation could not protect LRP5-HBM patients from age-related bone loss. This phenomenon deserves further study.

13.
Mol Cancer ; 23(1): 67, 2024 04 01.
Article in English | MEDLINE | ID: mdl-38561768

ABSTRACT

Gastrointestinal cancer (GIC) is the most prevalent and highly metastatic malignant tumor and has a significant impact on mortality rates. Nevertheless, the swift advancement of contemporary technology has not seamlessly aligned with the evolution of detection methodologies, resulting in a deficit of innovative and efficient clinical assays for GIC. Given that exosomes are preferentially released by a myriad of cellular entities, predominantly originating from neoplastic cells, this confers exosomes with a composition enriched in cancer-specific constituents. Furthermore, exosomes exhibit ubiquitous presence across diverse biological fluids, endowing them with the inherent advantages of non-invasiveness, real-time monitoring, and tumor specificity. The unparalleled advantages inherent in exosomes render them as an ideal liquid biopsy biomarker for early diagnosis, prognosticating the potential development of GIC metastasis.In this review, we summarized the latest research progress and possible potential targets on cancer-derived exosomes (CDEs) in GIC with an emphasis on the mechanisms of exosome promoting cancer metastasis, highlighting the potential roles of CDEs as the biomarker and treatment in metastatic GIC.


Subject(s)
Exosomes , Gastrointestinal Neoplasms , Humans , Exosomes/pathology , Biomarkers, Tumor , Biomarkers , Gastrointestinal Neoplasms/diagnosis , Gastrointestinal Neoplasms/pathology , Liquid Biopsy/methods
14.
Brief Bioinform ; 25(3)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38670160

ABSTRACT

Genome assembly remains to be a major task in genomic research. Despite the development over the past decades of different assembly software programs and algorithms, it is still a great challenge to assemble a complete genome without any gaps. With the latest DNA circular consensus sequencing (CCS) technology, several assembly programs can now build a genome from raw sequencing data to contigs; however, some complex sequence regions remain as unresolved gaps. Here, we present a novel gap-filling software, DEGAP (Dynamic Elongation of a Genome Assembly Path), that resolves gap regions by utilizing the dual advantages of accuracy and length of high-fidelity (HiFi) reads. DEGAP identifies differences between reads and provides 'GapFiller' or 'CtgLinker' modes to eliminate or shorten gaps in genomes. DEGAP adopts an iterative elongation strategy that automatically and dynamically adjusts parameters according to three complexity factors affecting the genome to determine the optimal extension path. DEGAP has already been successfully applied to decipher complex genomic regions in several projects and may be widely employed to generate more gap-free genomes.


Subject(s)
Algorithms , Software , Genomics/methods , Sequence Analysis, DNA/methods , Genome , High-Throughput Nucleotide Sequencing/methods
15.
J Colloid Interface Sci ; 667: 199-211, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38636222

ABSTRACT

The catalytic performance of immobilized lipase is greatly influenced by functional support, which attracts growing interest for designing supports to achieve their promotive catalytic activity. Many lipases bind strongly to hydrophobic surfaces where they undergo interfacial activation. Herein, the behavioral differences of lipases with distinct lid structures on interfaces of varying hydrophobicity levels were firstly investigated by molecular simulations. It was found that a reasonable hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation. Building on these findings, a novel "nest"-like superhydrophobic ZIFs (ZIFN) composed of hydrophobic ligands was prepared for the first time and used to immobilize lipase from Aspergillus oryzae (AOL@ZIFN). The AOL@ZIFN exhibited 2.0-folds higher activity than free lipase in the hydrolysis of p-Nitrophenyl palmitate (p-NPP). Especially, the modification of superhydrophobic ZIFN with an appropriate amount of hydrophilic tannic acid can significantly improve the activity of the immobilized lipase (AOL@ZIFN-TA). The AOL@ZIFN-TA exhibited 30-folds higher activity than free lipase, and still maintained 82% of its initial activity after 5 consecutive cycles, indicating good reusability. These results demonstrated that nanomaterials with rational arrangement of the hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation and improve its activity, displaying the potential of the extensive application.


Subject(s)
Enzymes, Immobilized , Hydrophobic and Hydrophilic Interactions , Lipase , Surface Properties , Lipase/chemistry , Lipase/metabolism , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Aspergillus oryzae/enzymology , Molecular Dynamics Simulation , Hydrolysis , Nanostructures/chemistry , Particle Size
16.
Food Chem ; 449: 139246, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38604035

ABSTRACT

The levels of metabolites in honey are influenced by floral origin, production region, and bee species. However, how environmental factors affect honey quality remains unclear. Based on untargeted metabolomics and using UPLC Q-Orbitrap MS, we analyzed 3596 metabolites in 51 honey samples from Yunnan and Shennongjia. Comparative analysis revealed that geniposidic acid, kynurenic acid and caffieine accumulated at significantly different levels between Shennongjia and Yunnan honey. Based on cluster structure analysis, 36 Yunnan honey samples were divided into two distinct groups by altitude. Notably, quercetin, hyperoside, taxifolin, rutin, tryptophan, astragalin and phenylalanine were higher levels in high-altitude honey (>1700 m), whereas abscisic acid was higher levels in low-altitude honey (≤1700 m). Among these, significantly elevated levels of hyperoside, taxfolin, astragalin, and tryptophan were observed in honey collected from high-altitude areas in Shennongjia. Our findings highlight the effect of altitude on honey health-promoting components, providing valuable insights into honey quality.


Subject(s)
Altitude , Honey , Honey/analysis , Animals , Bees/metabolism , China , Metabolomics , Chromatography, High Pressure Liquid
17.
Int J Biol Macromol ; 268(Pt 1): 131843, 2024 May.
Article in English | MEDLINE | ID: mdl-38663701

ABSTRACT

Highly oxidative reactive oxygen species (ROS) attack protein structure and regulate its functional properties. The molecular structures and functional characteristics of egg white (EW) protein (EWP) during 28 d of aerobic or anaerobic storage were explored to investigate the "self-driven" oxidation mechanism of liquid EW mediated by endogenous ROS signaling. Results revealed a significant increase in turbidity during the storage process, accompanied by protein crosslinking aggregation. The ROS yield initially increased and then decreased, leading to a substantial increase in carbonyl groups and tyrosine content. The free sulfhydryl groups and molecular flexibility in EWP exhibited synchronicity with ROS production, reflecting the self-repairing ability of cysteine residues in EWP. Fourier-transform infrared spectroscopy indicated stable crosslinking between EWP molecules in the early oxidation stage. However, continuous ROS attacks accelerated EWP degradation. Compared with the control group, the aerobic-stimulated EWP showed a significant decrease in foaming capacity from 30.5 % to 9.6 %, whereas the anaerobic-stimulated EWP maintained normal levels. The emulsification performance exhibited an increasing-then-decreasing trend. In conclusion, ROS acted as the predominant factor causing deterioration of liquid EW, triggering moderate oxidation that enhanced the superior foaming and emulsifying properties of EWP, and excessive oxidation diminished the functional characteristics by affecting the molecular structure.


Subject(s)
Egg White , Oxidation-Reduction , Reactive Oxygen Species , Reactive Oxygen Species/metabolism , Egg White/chemistry , Emulsions/chemistry , Egg Proteins/chemistry , Animals , Spectroscopy, Fourier Transform Infrared
18.
Angew Chem Int Ed Engl ; 63(24): e202405139, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38588277

ABSTRACT

It remains challenging to comprehensively understand the packing models of conjugated polymers, in which side chains play extremely critical roles. The side chains are typically flexible and non-conductive and are widely used to improve the polymer solubility in organic solutions. Herein, a buffer chain model is proposed to describe link between conjugated backbone and side chains for understanding the relationship of crystallization competition of conductive conjugated backbones and non-conductive side chains. A longer buffer chain is beneficial for alleviating such crystallization competition and further promoting the spontaneous packing of conjugated backbones, resulting in enhanced charge transport properties. Our results provide a novel concept for designing conjugated polymers towards ordered organization and enhanced electronic properties and highlight the importance of balancing the competitive interactions between different parts of conjugated polymers.

19.
Nat Commun ; 15(1): 2736, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38548785

ABSTRACT

Optimizing thermoelectric conversion efficiency requires the compromise of electrical and thermal properties of materials, which are hard to simultaneously improve due to the strong coupling of carrier and phonon transport. Herein, a one-pot approach realizing simultaneous second phase and Cu vacancies modulation is proposed, which is effective in synergistically optimizing thermoelectric performance in copper sulfides. Multiple lattice defects, including nanoprecipitates, dislocations, and nanopores are produced by adding a refined ratio of Sn and Se. Phonon transport is significantly suppressed by multiple mechanisms. An ultralow lattice thermal conductivity is therefore obtained. Furthermore, extra Se is added in the copper sulfide for optimizing electrical transport properties by inducing generating Cu vacancies. Ultimately, an excellent figure of merit of ~1.6 at 873 K is realized in the Cu1.992SSe0.016(Cu2SnSe4)0.004 bulk sample. The simple strategy of inducing compositional and structural modulation for improving thermoelectric parameters promotes low-cost high-performance copper sulfides as alternatives in thermoelectric applications.

20.
J Am Chem Soc ; 146(12): 8727-8736, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38487899

ABSTRACT

The practical application of thermoelectric devices requires both high-performance n-type and p-type materials of the same system to avoid possible mismatches and improve device reliability. Currently, environmentally friendly SnTe thermoelectrics have witnessed extensive efforts to develop promising p-type transport, making it rather urgent to investigate the n-type counterparts with comparable performance. Herein, we develop a stepwise optimization strategy for improving the transport properties of n-type SnTe. First, we improve the n-type dopability of SnTe by PbSe alloying to narrow the band gap and obtain n-type transport in SnTe with halogen doping over the whole temperature range. Then, we introduce additional Pb atoms to compensate for the cationic vacancies in the SnTe-PbSe matrix, further enhancing the electron carrier concentration and electrical performance. Resultantly, the high-ranged thermoelectric performance of n-type SnTe is substantially optimized, achieving a peak ZT of ∼0.75 at 573 K with a high average ZT (ZTave) exceeding 0.5 from 300 to 823 K in the (SnTe0.98I0.02)0.6(Pb1.06Se)0.4 sample. Moreover, based on the performance optimization on n-type SnTe, for the first time, we fabricate an all-SnTe-based seven-pair thermoelectric device. This device can produce a maximum output power of ∼0.2 W and a conversion efficiency of ∼2.7% under a temperature difference of 350 K, demonstrating an important breakthrough for all-SnTe-based thermoelectric devices. Our research further illustrates the effectiveness and application potential of the environmentally friendly SnTe thermoelectrics for mid-temperature power generation.

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