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1.
Curr Res Food Sci ; 8: 100772, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38840807

RESUMEN

The aroma types of cream cheese affect its commercial value and consumer acceptability. However, the types of volatile substances and sensory characteristics of cream cheese at different fermentation stages are still unclear. Therefore, in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) were used to analyze the volatile substances in cream cheese fermentation. Orthogonal partial least squares discriminant analysis (OPLS-DA), odor activity value (OAV), relative odor activity value (ROAV) and variable projection importance (VIP) were used to identify the characteristic flavor substances in cream cheese fermentation. Finally, the relationship between key flavor substances and sensory characteristics was determined by partial least squares (PLS) analysis. A total of 34 and 36 volatile organic compounds were identified by HS-SPME-GC-MS and HS-GC-MS, respectively, and 14 characteristic flavor substances were found, based on VIP, ROAV and OAV models. Combined with sensory analysis and flavor substance changes, it was found that the cream cheese fermented for 15 d had the best flavor and taste. This study reveals the characteristics and contribution of volatile substances in cream cheese at different fermentation stages, which provides new insights into improving flavor and quality control.

2.
Anal Bioanal Chem ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704473

RESUMEN

Nanoceria have demonstrated a wide array of catalytic activity similar to natural enzymes, holding considerable significance in the colorimetric detection of alkaline phosphatase (ALP), which is a biomarker of various biological disorders. However, the issues of physiological stability and formation of protein corona, which are strongly related to their surface chemistry, limit their practical application. In this work, CeO2 nanoparticles characterized by enhanced dimensional uniformity and specific surface area were synthesized, followed by encapsulation with various polymers to further increase catalytic activity and physiological stability. Notably, the CeO2 nanoparticles encapsulated within each polymer exhibited improved catalytic characteristics, with PAA-capped CeO2 exhibiting the highest performance. We further demonstrated that the PAA-CeO2 obtained with enhanced catalytic activity was attributed to an increase in surface negative charge. PAA-CeO2 enabled the quantitative assessment of AA activity within a wide concentration range of 10 to 60 µM, with a detection limit of 0.111 µM. Similarly, it allowed for the evaluation of alkaline phosphatase activity throughout a broad range of 10 to 80 U/L, with a detection limit of 0.12 U/L. These detection limits provided adequate sensitivity for the practical detection of ALP in human serum.

3.
bioRxiv ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38168313

RESUMEN

Actinobacteria, the bacterial phylum most renowned for natural product discovery, has been established as a valuable source for drug discovery and biotechnology but is underrepresented within accessible genome and strain collections. Herein, we introduce the Natural Products Discovery Center (NPDC), featuring 122,449 strains assembled over eight decades, the genomes of the first 8490 NPDC strains (7142 Actinobacteria), and the online NPDC Portal making both strains and genomes publicly available. A comparative survey of RefSeq and NPDC Actinobacteria highlights the taxonomic and biosynthetic diversity within the NPDC collection, including three new genera, hundreds of new species, and ~7000 new gene cluster families. Selected examples demonstrate how the NPDC Portal's strain metadata, genomes, and biosynthetic gene clusters can be leveraged using genome mining approaches. Our findings underscore the ongoing significance of Actinobacteria in natural product discovery, and the NPDC serves as an unparalleled resource for both Actinobacteria strains and genomes.

4.
Front Genet ; 14: 1243730, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37554407

RESUMEN

Previous studies demonstrated Y chromosome haplogroup C2a-M48-SK1061 is the only founding paternal lineage of all Tungusic-speaking populations. To infer the differentiation history of these populations, we studied more sequences and constructed downstream structure of haplogroup C2a-M48-SK1061 with better resolution. In this study, we generated 100 new sequences and co-analyzed 140 sequences of C2a-M48-SK1061 to reconstruct a highly revised phylogenetic tree with age estimates. We also performed the analysis of the geographical distribution and spatial autocorrelation of sub-branches. Dozens of new sub-branches were discovered, many sub-branches were nearly unique for Ewenki, Evens, Oroqen, Xibe, Manchu, Daur, and Mongolian. The topology of these unique sub-branches is the key evidence for understanding the complex evolutionary relationship between different Tungusic-speaking populations. The revised phylogeny provided a clear pattern for the differentiation history of haplogroup C2a-M48-SK1061 in the past 2,000 years. This study showed that the divergence pattern of founder lineage is essential to understanding the differentiation history of populations.

5.
J Ethnopharmacol ; 315: 116653, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37236383

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia minax Hance, whose seeds are known as "Ku-shi-lian" in China, have been used in Chinese folk medicine for treatment of rheumatism, dysentery, and skin itching. However, the anti-neuroinflammatory constituents of its leaves and their mechanism are rarely reported. AIM OF THE STUDY: To search for new anti-neuro-inflammatory compounds from the leaves of C. minax and elucidate their mechanism on anti-neuroinflammatory effect. MATERIALS AND METHODS: The main metabolites of the ethyl acetate fraction from C. minax were analyzed and purified via HPLC and various column chromatography techniques. Their structures were elucidated on the basis of 1D and 2D NMR, HR-ESI-MS, and single crystal X-ray diffraction analysis. Anti-neuroinflammatory activity was evaluated in BV-2 microglia cells induced by LPS. The expression levels of molecules in NF-κB and MAPK signaling pathways were analyzed through western blotting. Meanwhile, the time- and dose-dependent expression of associated proteins such as iNOS and COX-2 were detected by western blotting. Furthermore, Compounds 1 and 3 were performed on the NF-κB p65 active site using molecular docking simulation to elucidate the molecular level inhibition mechanism. RESULTS: 20 cassane diterpenoids, including two novel ones (caeminaxins A and B) were isolated from the leaves of C. minax Hance. Caeminaxins A and B possessed a rare unsaturated carbonyl moiety in their structures. Most of the metabolites exhibited potent inhibition effects with IC50 values ranging from 10.86 ± 0.82 to 32.55 ± 0.47 µM. Among them, caeminaxin A inhibited seriously the expression of iNOS and COX-2 proteins and restrained the phosphorylation of MAPK and the activation of NF-κB signaling pathways in BV-2 cells. The anti-neuro-inflammatory mechanism of caeminaxin A has been studied systematically for the first time. Furthermore, biosynthesis pathways for compounds 1-20 were discussed. CONCLUSIONS: The new cassane diterpenoid, caeminaxin A, alleviated the expression of iNOS and COX-2 protein and down-regulated of intracellular MAPK and NF-κB signaling pathways. The results implied that cassane diterpenoids had potential to be developed into therapeutic agents for neurodegenerative disorders such as Alzheimer's disease.


Asunto(s)
Caesalpinia , Diterpenos , FN-kappa B/metabolismo , Caesalpinia/química , Microglía/metabolismo , Ciclooxigenasa 2 , Simulación del Acoplamiento Molecular , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Hojas de la Planta/metabolismo , Diterpenos/farmacología , Diterpenos/uso terapéutico , Diterpenos/química , Lipopolisacáridos/farmacología
6.
Food Chem ; 423: 136299, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37178602

RESUMEN

Lipolysis and flavor development during fermentation of sour cream were studied by evaluating the physicochemical changes, sensory differences and volatile components. The fermentation caused significant changes in pH, viable count and sensory evaluation. The peroxide value (POV) decreased after reaching the maximum value of 1.07 meq/kg at 15 h, while thiobarbituric acid reactive substances (TBARS) increased continuously with the accumulation of secondary oxidation products. The Free fatty acids (FFAs) in sour cream were mainly myristic, palmitic and stearic. GC-IMS was used to identify the flavor properties. A total of 31 volatile compounds were identified, among which the contents of characteristic aromatic substances such as ethyl acetate, 1-octen-3-one and hexanoic acid were increased. The results suggest that lipid changes and flavor formation in sour cream are influenced by fermentation time. Furthermore, flavor compounds may be related to lipolysis such as 1-octen-3-one and 2- heptanol were also observed.


Asunto(s)
Lipólisis , Compuestos Orgánicos Volátiles , Cetonas , Alimentos , Fermentación
7.
Org Lett ; 25(6): 961-965, 2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36735280

RESUMEN

Neogrisemycin (1) was isolated from recombinant Streptomyces albus J1074 strain SB4061 expressing an engineered thioangucycline (TAC) biosynthetic gene cluster (BGC). The structure and absolute configuration of 1 were established by a combination of mass spectrometry, nuclear magnetic resonance, and single-crystal X-ray diffraction analyses. Like the TACs, 1 was also proposed to derive non-enzymatically from the common epoxide (8), the nascent product encoded by the tac BGC, mediated by endogenous hydrogen trisulfide.


Asunto(s)
Streptomyces griseus , Streptomyces , Streptomyces/genética , Familia de Multigenes , Espectroscopía de Resonancia Magnética
8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1010131

RESUMEN

OBJECTIVE@#To explore the potential mechanism of resistance to axitinib in clear cell renal cell carcinoma (ccRCC), with a view to expanding the understanding of axitinib resistance, facilitating the design of more specific treatment options, and improving the treatment effectiveness and survival prognosis of patients.@*METHODS@#By exploring the half maximum inhibitory concentration (IC50) of axitinib on ccRCC cell lines 786-O and Caki-1, cell lines resistant to axitinib were constructed by repeatedly stimulated with axitinib at this concentration for 30 cycles in vitro. Cell lines that were not treated by axitinib were sensitive cell lines. The phenotypic differences of cell proliferation and apoptosis levels between drug resistant and sensitive lines were tested. Genes that might be involved in the drug resistance process were screened from the differentially expressed genes that were co-upregulated in the two drug resistant lines by transcriptome sequencing. The expression level of the target gene in the drug resistant lines was verified by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB). The expression differences of the target gene in ccRCC tumor tissues and adjacent tissues were analyzed in the Gene Expression Profiling Interactive Analysis (GEPIA) public database, and the impact of the target gene on the prognosis of ccRCC patients was analyzed in the Kaplan-Meier Plotter (K-M Plotter) database. After knocking down the target gene in the drug resistant lines using RNA interference by lentivirus vector, the phenotypic differences of the cell lines were tested again. WB was used to detect the levels of apoptosis-related proteins in the different treated cell lines to find molecular pathways that might lead to drug resistance.@*RESULTS@#Cell lines 786-O-R and Caki-1-R resistant to axitinib were successfully constructed in vitro, and their IC50 were significantly higher than those of the sensitive cell lines (10.99 μmol/L, P < 0.01; 11.96 μmol/L, P < 0.01, respectively). Cell counting kit-8 (CCK-8) assay, colony formation, and 5-ethynyl-2 '-deoxyuridine (EdU) assay showed that compared with the sensitive lines, the proliferative ability of the resistant lines decreased, but apoptosis staining showed a significant decrease in the level of cell apoptosis of the resistant lines (P < 0.01). Although resistant to axitinib, the resistant lines had no obvious new replicated cells in the environment of 20 μmol/L axitinib. Nuclear protein 1 (NUPR1) gene was screened by transcriptome sequencing, and its RNA (P < 0.0001) and protein expression levels significantly increased in the resistant lines. Database analysis showed that NUPR1 was significantly overexpressed in ccRCC tumor tissue (P < 0.05); the ccRCC patients with higher expression ofNUPR1had a worse survival prognosis (P < 0.001). Apoptosis staining results showed that knockdown ofNUPR1inhibited the anti-apoptotic ability of the resistant lines to axitinib (786-O, P < 0.01; Caki-1, P < 0.05). WB results showed that knocking downNUPR1decreased the protein level of B-cell lymphoma-2 (BCL2), increased the protein level of BCL2-associated X protein (BAX), decreased the protein level of pro-caspase3, and increased the level of cleaved-caspase3 in the resistant lines after being treated with axitinib.@*CONCLUSION@#ccRCC cell lines reduce apoptosis through theNUPR1 -BAX/ BCL2 -caspase3 pathway, which is involved in the process of resistance to axitinib.


Asunto(s)
Humanos , Carcinoma de Células Renales/metabolismo , Axitinib/farmacología , Neoplasias Renales/metabolismo , Proteína X Asociada a bcl-2 , Proteínas Nucleares , Línea Celular Tumoral , Apoptosis , Proliferación Celular
9.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-970568

RESUMEN

The present study optimized the ethanol extraction process of Ziziphi Spinosae Semen-Schisandrae Sphenantherae Fructus drug pair by network pharmacology and Box-Behnken method. Network pharmacology and molecular docking were used to screen out and verify the potential active components of Ziziphi Spinosae Semen-Schisandrae Sphenantherae Fructus, and the process evaluation indexes were determined in light of the components of the content determination under Ziziphi Spinosae Semen and Schisandrae Sphenantherae Fructus in the Chinese Pharmacopoeia(2020 edition). The analytic hierarchy process(AHP) was used to determine the weight coefficient of each component, and the comprehensive score was calculated as the process evaluation index. The ethanol extraction process of Ziziphi Spinosae Semen-Schisandrae Sphenantherae Fructus was optimized by the Box-Behnken method. The core components of the Ziziphi Spinosae Semen-Schisandrae Sphenantherae Fructus drug pair were screened out as spinosin, jujuboside A, jujuboside B, schisandrin, schisandrol, schisandrin A, and schisandrin B. The optimal extraction conditions obtained by using the Box-Behnken method were listed below: extraction time of 90 min, ethanol volume fraction of 85%, and two times of extraction. Through network pharmacology and molecular docking, the process evaluation indexes were determined, and the optimized process was stable, which could provide an experimental basis for the production of preparations containing Ziziphi Spinosae Semen-Schisandrae Sphenantherae Fructus.


Asunto(s)
Etanol , Simulación del Acoplamiento Molecular , Farmacología en Red , Semillas/química , Ziziphus/química , Extractos Vegetales/química , Schisandra/química , Frutas/química , Tecnología Farmacéutica
10.
Artículo en Inglés | MEDLINE | ID: mdl-35591750

RESUMEN

In September 2021, a household cluster of three typhoid cases was investigated by Queensland public health authorities. Through case interviews and molecular typing, the investigation revealed chronic carriage of Salmonella Typhi persisting at least 12 years in the index case. This case report summarises the investigation and highlights the complexity of chronic pathogen carriage in the control and management of typhoid disease. Our findings raise considerations for prevention and treatment guidelines in Australia and demonstrate the beneficial role of molecular typing for complex case investigations.


Asunto(s)
Salmonella typhi , Fiebre Tifoidea , Australia/epidemiología , Humanos , Queensland/epidemiología , Salmonella , Fiebre Tifoidea/epidemiología
11.
J Hazard Mater ; 435: 128976, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35472541

RESUMEN

Since the excess exposure to F- may induce serious issues to human health, the effective adsorption and sensitive detection of F- is essential. Therefore, carbon dots (CDs) capped CeO2 (CeO2@CDs) was synthesized via hydrothermal treatment of tannic acid and CeCl3. Due to abundant phenolic hydroxyl are reserved and excellent hydrophilicity, CeO2@CDs possess high F- adsorption capacity. The partition coefficient parameters (PC) are determined to be 2.65 L/g, which is comparable with previous work. The kinetics results and adsorption isotherm are consistent with pseudo-second-order model and Freundlich model, respectively, indicating the chemisorption dominate the adsorption, mainly via the ion exchange between hydroxyl and F-. Since phenolic hydroxyl existed on the CeO2@CDs, synergetic effect of CDs and CeO2 contribute to superior ROS eliminating capacity, even at acidic conditions. Moreover, due to the ROS scavenging of CeO2 @CDs abilities can be potentiated by F-, colorimetric detection of F- can be realized via horseradish peroxidase as an indicator. The linear range is 0.3-2.1 mM with limit of detection is 0.13 mg/L. The current results imply that CeO2@CDs possess potential in both efficient removal and sensitive detection of F- related contamination issues and elucidation of development to address other anions related issues.


Asunto(s)
Cerio , Nanopartículas , Carbono , Fluoruros , Humanos , Especies Reactivas de Oxígeno
12.
Oncol Lett ; 23(2): 48, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34992681

RESUMEN

Long non-coding (lnc)RNAs have been recognized as important regulators in gastric cancer. lncRNA GAS8-AS1 is considered a tumor suppressor in multiple types of cancer, such as papillary thyroid carcinoma, ovarian cancer and colorectal cancer. However, the specific role of GAS8-AS1 in gastric cancer remains to be fully elucidated. The aim of the present study was to investigate the role of GAS8-AS1 in gastric cancer and its potential underlying mechanisms of action. The expression levels of GAS8-AS1, microRNA (miR)-21-3p, PTEN and pyruvate dehydrogenase (E1) alpha subunit gene (PDHA1) in gastric cancer and non-cancerous tissues, as well as in gastric cancer cell lines, were detected using reverse transcription-quantitative PCR. Cell proliferation was detected by using a Cell Counting Kit-8 assay. Cell migration and invasion were detected using a Transwell assay. Results of the present study demonstrated that the expression levels of GAS8-AS1 in gastric cancer tissues were significantly decreased, whereas its expression did not differ among cancer tissues at different clinical stages. Low expression levels of GAS8-AS1 predicted poor 5-year survival rates for 70 patients with gastric adenocarcinoma from the Affiliated Hospital of Xuzhou Medical University (Xuzhou, China) during patient follow-up. In addition, the expression levels of miR-21-3p were markedly increased in cancer tissues, and miR-21-3p expression was negatively associated with the expression of GAS8-AS1. The direct interaction between GAS8-AS1 and miR-21-3p was predicted using the starBase database and was confirmed by using an RNA pull-down assay. In gastric cell lines, the overexpression of GAS8-AS1 reduced the expression levels of mature miR-21-3p but did not affect the expression of miR-21-3p precursor, while the overexpression of miR-21-3p did not, in turn, affect the expression of GAS8-AS1. In addition, the overexpression of GAS8-AS1 inhibited cancer cell proliferation, while the overexpression of miR-21-3p promoted cancer cell proliferation and attenuated the effects of GAS8-AS1. Overexpression of miR-21-3p promoted cancer cell migration and invasion, whereas overexpression of GAS8-AS1 did not affect cell migration or invasion. In summary, results of the present study have demonstrated that GAS8-AS1 acts as a tumor suppressor in gastric cancer, and it may inhibit cancer cell proliferation by downregulating miR-21-3p.

13.
Asian J Surg ; 45(6): 1231-1236, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34507839

RESUMEN

OBJECTIVE: To investigate the expression of long non-coding RNA LINC01279 in gastric cancer and its relationship with the clinicopathological features and prognosis of gastric cancer patients. METHODS: Serum, gastric cancer and adjacent tissue samples from 90-patients with gastric-cancer treated by surgery and serum samples from 90-healthy adults were collected. The expression level of LINC01279 was analyzed by RT-PCR. The clinical baseline data of gastric cancer patients were obtained. Correlation between the expression level of LINC01279 and the clinicopathological characteristics of gastric cancer patients was assessed. RESULTS: LINC01279 was highly expressed in gastric cancer tissues and serum of gastric cancer patients (P < 0.05). The expression level of lncRNA 01279 was closely related to vascular invasion, nerve invasion, T-stage, lymph node metastasis, and advanced clinical-stage of gastric cancer (P < 0.05). The expression level was not correlated with gender, age, tumor size, location, and differentiation. There was a significant negative correlation between the expression of LINC01279 and the overall survival of gastric-cancer patients (P < 0.05). CONCLUSION: LINC01279 is highly expressed in gastric-cancer tissues and serum, which is closely related to tumor-invasion. Serum LINC01279 is a better prognostic indicator of invasive cancer than current tumor markers.


Asunto(s)
Adenocarcinoma , ARN Largo no Codificante , Neoplasias Gástricas , Adenocarcinoma/genética , Adulto , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Humanos , Metástasis Linfática , Pronóstico , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía
14.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-927987

RESUMEN

The present study developed an ultra-fast liquid chromatography coupled with triple quadrupole-linear ion trap composite mass spectrometry(UHPLC-QTRAP-MS) to simultaneously determine the content of potential active components in Scutellariae Barbatae Herba and also to provide a reference approach for screening out the differential quality control components among different batches of Scutellariae Barbatae Herba. Chromatographic separations were conducted on a Thermo Acclaim~(TM) RSLC 120 C_(18) column(3.0 mm×100 mm, 2.2 μm) in a gradient program. The mobile phase consisted of 0.1% aqueous formic acid and acetonitrile, and the column temperature was maintained at 40 ℃. The flow rate was 0.4 mL·min~(-1) and the injection volume was 2 μL. The targeted compounds were monitored in the multiple reaction monitoring(MRM) mode. The acquired data were processed by hierarchical cluster analysis(HCA) and partial least square discriminant analysis(PLS-DA). Sixteen compounds all showed good linear relationship within the corresponding linear ranges and the R~2 values were all higher than 0.993 2. The RSDs of precision, repeatability, and stability were less than or equal to 3.7%. Mean recovery rates were in the range of 95.67% and 104.8% with RSDs≤3.2%. According to HCA and PLS-DA, all samples were clustered into four categories. Scutellarin, acteoside, scutellarein, and scutebarbatine X(VIP>1) were considered as differential chemical markers in the four categories. In conclusion, the developed method can be used for the simulta-neous determination of the multiple components and quality control of Scutellariae Barbatae Herba.


Asunto(s)
Quimiometría , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Scutellaria , Espectrometría de Masas en Tándem/métodos
15.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-956206

RESUMEN

Objective:A case-control association analysis was performed to investigate if the single nucleotide polymorphisms (SNPs) of N-cadherin(CDH2) gene is implicated in schizophrenia in a Han Chinese population.Methods:A total of 528 patients with paranoid schizophrenia and 528 healthy controls were recruited from northern Henan province to analyze 25 SNPs located in CDH2 gene.The clinical symptoms of 267 first-episode schizophrenia patients were evaluated with positive and negative syndrome scale (PANSS), and the correlation between CDH2 gene and clinical symptoms was analyzed by SNPStats software online.Results:Allele frequencies of rs9951577 and rs1231268 were significantly correlated with schizophrenia( P<0.05), genotype frequency of rs1639387 was significantly correlated with schizophrenia( P=0.044). After gender classification, SNPs rs1789470 and rs28365328 were found to be significantly correlated with schizophrenia in female patients ( P=0.044, 0.019). In addition, the study found that CDH2 was correlated with the clinical characteristics of schizophrenia( P<0.05), and the negative factor score of patients between GG type rs1231268 and the other two genotypes (AG+ AA) ((21.12±8.41) vs (18.87±7.52)) was statistically significant ( P<0.05). Conclusion:CDH2 gene may be one of the susceptibility genes to SZ, and has definite correlation with clinical negative symptoms.

16.
Nat Commun ; 12(1): 5672, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34584078

RESUMEN

Nature forms S-S bonds by oxidizing two sulfhydryl groups, and no enzyme installing an intact hydropersulfide (-SSH) group into a natural product has been identified to date. The leinamycin (LNM) family of natural products features intact S-S bonds, and previously we reported an SH domain (LnmJ-SH) within the LNM hybrid nonribosomal peptide synthetase (NRPS)-polyketide synthase (PKS) assembly line as a cysteine lyase that plays a role in sulfur incorporation. Here we report the characterization of an S-adenosyl methionine (SAM)-dependent hydropersulfide methyltransferase (GnmP) for guangnanmycin (GNM) biosynthesis, discovery of hydropersulfides as the nascent products of the GNM and LNM hybrid NRPS-PKS assembly lines, and revelation of three SH domains (GnmT-SH, LnmJ-SH, and WsmR-SH) within the GNM, LNM, and weishanmycin (WSM) hybrid NRPS-PKS assembly lines as thiocysteine lyases. Based on these findings, we propose a biosynthetic model for the LNM family of natural products, featuring thiocysteine lyases as PKS domains that directly install a -SSH group into the GNM, LNM, or WSM polyketide scaffold. Genome mining reveals that SH domains are widespread in Nature, extending beyond the LNM family of natural products. The SH domains could also be leveraged as biocatalysts to install an -SSH group into other biologically relevant scaffolds.


Asunto(s)
Productos Biológicos/metabolismo , Liasas de Carbono-Azufre/metabolismo , Cisteína/análogos & derivados , Metiltransferasas/metabolismo , Sintasas Poliquetidas/metabolismo , Sulfuros/metabolismo , Animales , Productos Biológicos/química , Cisteína/metabolismo , Cistina/química , Cistina/metabolismo , Humanos , Lactamas/síntesis química , Lactamas/química , Lactamas/metabolismo , Macrólidos/síntesis química , Macrólidos/química , Macrólidos/metabolismo , Modelos Químicos , Estructura Molecular , Péptido Sintasas/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Especificidad por Sustrato , Sulfuros/química , Tiazoles/síntesis química , Tiazoles/química , Tiazoles/metabolismo , Tionas/síntesis química , Tionas/química , Tionas/metabolismo , Dominios Homologos src
17.
Mikrochim Acta ; 188(5): 154, 2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33821295

RESUMEN

Mitochondria, as the energy factory of most cells, are not only responsible for the generation of adenosine triphosphoric acid (ATP) but also essential targets for therapy and diagnosis of various diseases, especially cancer. The safe and potential nanoplatform which can deliver various therapeutic agents to cancer cells and mitochondrial targeted imaging is urgently required. Herein, Au nanoparticles (AuNPs), mesoporous silica nanoparticles (MSN), cationic ligand (triphenylphosphine (TPP)), doxorubicin (DOX), and carbon nanodots (CDs) were utilized to fabricate mitochondrial targeting drug delivery system (denoted as CDs(DOX)@MSN-TPP@AuNPs). Since AuNPs, as the gatekeepers, can be etched by intracellular glutathione (GSH) via ligand exchange induced etching process, DOX can be released into cells in a GSH-dependent manner which results in the superior GSH-modulated tumor inhibition activity. Moreover, after etching by GSH, the CDs(DOX)@MSN-TPP@AuNPs can serve as promising fluorescent probe (λex = 633 nm, λem = 650 nm) for targeted imaging of mitochondria in living cells with near-infrared fluorescence. The induction of apoptosis derived from the membrane depolarization of mitochondria is the primary anti-tumor route of CDs(DOX)@MSN-TPP@AuNPs. As a kind of GSH-responsive mitochondrial targeting nanoplatform, it holds great promising for effective cancer therapy and mitochondrial targeted imaging. The mitochondrial targeting drug delivery system was fabricated by AuNPs, MSN, TPP, and CDs. The nanoplatform can realize redox-responsive drug delivery and targeted imaging of mitochondria in living cells to improve the therapeutic efficiency and security.


Asunto(s)
Antineoplásicos/farmacología , Doxorrubicina/farmacología , Portadores de Fármacos/química , Colorantes Fluorescentes/química , Nanopartículas del Metal/química , Mitocondrias/metabolismo , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Carbono/química , Carbono/toxicidad , Línea Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/toxicidad , Liberación de Fármacos , Colorantes Fluorescentes/toxicidad , Glutatión/metabolismo , Oro/química , Oro/toxicidad , Humanos , Nanopartículas del Metal/toxicidad , Ratones , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Compuestos Organofosforados/química , Compuestos Organofosforados/toxicidad , Puntos Cuánticos/química , Puntos Cuánticos/toxicidad , Dióxido de Silicio/química , Dióxido de Silicio/toxicidad , Plata/química , Plata/toxicidad
18.
Mikrochim Acta ; 188(4): 141, 2021 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-33774694

RESUMEN

A redox-responsive chemodynamic therapy (CDT)-based theranostic system composed of hollow mesoporous MnO2 (H-MnO2), doxorubicin (DOX), and fluorescent (FL) carbon nanodots (CDs) is reported for the diagnosis and therapy of cancer. In general, since H-MnO2 can be degraded by intracellular glutathione (GSH) to form Mn2+ with excellent Fenton-like activity to generate highly reactive ·OH, the normal antioxidant defense system can be injured via consumption of GSH. This in turn can potentiate the cytotoxicity of CDT and release DOX. The cancer cells can be eliminated effectively by the nanoplatform via the synergistic effect of chemotherapy and CDT. The FL of CDs can be restored after H-MnO2 is degraded which blocked the fluorescence resonance energy transfer process between CDs as an energy donor and H-MnO2 as an FL acceptor. The GSH can be determined by recovery of the FL and limit of detection is 1.30 µM with a linear range of 0.075-0.825 mM. This feature can be utilized to efficiently distinguish cancerous cells from normal ones based on different GSH concentrations in the two types of cells. As a kind of CDT-based theranostic system responsive to GSH, simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) in a single nanoplatform can be achieved. The redox-responsive chemodynamic therapy (CDT)-based theranostic system is fabricated by H-MnO2, DOX, and fluorescent CDs. The nanoplatform can realize simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) to improve the therapeutic efficiency and security.


Asunto(s)
Antineoplásicos/farmacología , Doxorrubicina/farmacología , Colorantes Fluorescentes/química , Glutatión/análisis , Medicina de Precisión/métodos , Puntos Cuánticos/química , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Carbono/química , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/química , Liberación de Fármacos , Quimioterapia , Humanos , Límite de Detección , Ratones , Molibdeno/química , Neoplasias/diagnóstico , Óxidos/química , Espectrometría de Fluorescencia
19.
Am J Hum Biol ; 33(2): e23462, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32657006

RESUMEN

OBJECTIVES: Haplogroup C2a-M48 is the predominant paternal lineage of Tungusic-speaking populations, one of the largest population groups in Siberia. Up until now, the origins and dispersal of Tungusic-speaking populations have remained unclear. In this study, the demographic history of Tungusic-speaking populations was explored using the phylogenetic analysis of haplogroup C2a-M86, the major subbranch of C2a-M48. MATERIALS AND METHODS: In total, 18 newly generated Y chromosome sequences from C2a-M48 males and 20 previously available Y-chromosome sequences from this haplogroup were analyzed. A highly revised phylogenetic tree of haplogroup C2a-M86 with age estimates was reconstructed. Frequencies of this lineage in the literature were collected and a comprehensive analysis of this lineage in 13 022 individuals from 245 populations in Eurasia was performed. RESULTS: The distribution map of C2a-M48 indicated the most probable area of origin and diffusion route of this paternal lineage in North Eurasia. Most C2a-M86 samples from Tungusic-speaking populations belonged to the sublineage C2a-F5484, which emerged about 3300 years ago. We identified six unique sublineages corresponding to the Manchu, Evenks, Evens, Oroqen, and Daurpopulations; these sublineages diverged gradually over the past 1900 years. Notably, we observed a clear north-south dichotomous structure for sublineages derived from C2a-F5484, consistent with the internal north-south divergence of Tungusic languages and ethnic groups. CONCLUSIONS: We identified the important founding paternal haplogroup, C2a-F5484, for Tungusic-speaking populations as well as numerous unique subgroups of this haplogroup. We propose that the timeframe for the divergence of C2a-F5484 corresponds with the early differentiation of ancestral Tungusic-speaking populations.


Asunto(s)
Cromosomas Humanos Y/genética , Etnicidad/genética , Migración Humana , Filogenia , Haplotipos , Humanos , Masculino , Siberia/etnología
20.
Acta Physiologica Sinica ; (6): 17-25, 2021.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-878231

RESUMEN

This study was aimed to determine the effect of acute cerebral ischemia on the protein expression level of silent mating type information regulator 2 homolog 3 (Sirt3) in the neurons and clarify the pathological role of Sirt3 in acute cerebral ischemia. The mice with middle cerebral artery occlusion (MCAO) and primary cultured rat hippocampal neurons with oxygen glucose deprivation (OGD) were used as acute cerebral ischemia models in vivo and in vitro, respectively. Sirt3 overexpression was induced in rat hippocampal neurons by lentivirus transfection. Western blot was utilized to measure the changes in Sirt3 protein expression level. CCK8 assay was used to detect cell viability. Immunofluorescent staining was used to detect mitochondrial function. Transmission electron microscope was used to detect mitochondrial autophagy. The results showed that, compared with the normoxia group, hippocampal neurons from OGD1 h/reoxygenation 2 h (R2 h) and OGD1 h/R12 h groups exhibited down-regulated Sirt3 protein expression levels. Compared with contralateral normal brain tissue, the ipsilateral penumbra region from MCAO1 h/reperfusion 24 h (R24 h) and MCAO1 h/R72 h groups exhibited down-regulated Sirt3 protein expression levels, while there was no significant difference between the Sirt3 protein levels on both sides of sham group. OGD1 h/R12 h treatment damaged mitochondrial function, activated mitochondrial autophagy and reduced cell viability in hippocampal neurons, whereas Sirt3 over-expression attenuated the above damage effects of OGD1 h/R12 h treatment. These results suggest that acute cerebral ischemia results in a decrease in Sirt3 protein level. Sirt3 overexpression can alleviate acute cerebral ischemia-induced neural injuries by improving the mitochondrial function. The current study sheds light on a novel strategy against neural injuries caused by acute cerebral ischemia.


Asunto(s)
Animales , Ratones , Ratas , Isquemia Encefálica , Regulación hacia Abajo , Infarto de la Arteria Cerebral Media , Mitocondrias , Neuronas/metabolismo , Daño por Reperfusión , Sirtuina 3/metabolismo , Sirtuinas
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