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As a fundamental tool in synthetic biology, promoters are pivotal in regulating gene expression, enabling precise genetic control and spurring innovation across diverse biotechnological applications. However, most advances in engineered genetic systems rely on host-specific regulation of the genetic portion. With the burgeoning diversity of synthetic biology chassis cells, there emerges a pressing necessity to broaden the universal promoter toolkit spectrum, ensuring adaptability across various microbial chassis cells for enhanced applicability and customization in the evolving landscape of synthetic biology. In this study, we analyzed and validated the primary structures of natural endogenous promoters from Escherichia coli, Bacillus subtilis, Corynebacterium glutamicum, Saccharomyces cerevisiae, and Pichia pastoris, and through strategic integration and rational modification of promoter motifs, we developed a series of cross-species promoters (Psh) with transcriptional activity in five strains (prokaryotic and eukaryotic). This series of cross species promoters can significantly expand the synthetic biology promoter toolkit while providing a foundation and inspiration for standardized development of universal components The combinatorial use of key elements from prokaryotic and eukaryotic promoters presented in this study represents a novel strategy that may offer new insights and methods for future advancements in promoter engineering.
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The serine-/arginine-rich splicing factor 2 (SRSF2) plays pivotal roles in pre-mRNA processing and gene transcription. Recurrent mutations, particularly a proline-to-histidine substitution at position 95 (P95H), are common in neoplastic diseases. Here, we assess SRSF2's diverse functions in squamous cell carcinoma. We show that SRSF2 deletion or homozygous P95H mutation both cause extensive DNA damage leading to cell-cycle arrest. Mechanistically, SRSF2 regulates efficient bi-directional transcription of DNA replication and repair genes, independent from its function in splicing. Further, SRSF2 haploinsufficiency induces DNA damage without halting the cell cycle. Exposing mouse skin to tumor-promoting carcinogens enhances the clonal expansion of heterozygous Srsf2 P95H epidermal cells but unexpectedly inhibits tumor formation. To survive carcinogen treatment, Srsf2 P95H+/- cells undergo substantial transcriptional rewiring and restore bi-directional gene expression. Thus, our study underscores SRSF2's importance in regulating transcription to orchestrate the cell cycle and the DNA damage response.
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Squalene (C30H50) is an acyclic triterpenoid compound renowned for its myriad physiological functions, such as anticancer and antioxidative properties, rendering it invaluable in both the food and pharmaceutical sectors. Due to the natural resource constraints, microbial fermentation has emerged as a prominent trend. Schizochytrium sp., known to harbor the intact mevalonate acid (MVA) pathway, possesses the inherent capability to biosynthesize squalene. However, there is a dearth of reported key genes in both the MVA and the squalene synthesis pathways, along with the associated promoter elements for their modification. This study commenced by cloning and characterizing 13 endogenous promoters derived from transcriptome sequencing data. Subsequently, five promoters exhibiting varying expression intensities were chosen from the aforementioned pool to facilitate the overexpression of the squalene synthase gene squalene synthetase (SQS), pivotal in the MVA pathway. Ultimately, a transformed strain designated as SQS-3626, exhibiting squalene production 2.8 times greater than that of the wild-type strain, was identified. Finally, the optimization of nitrogen source concentrations and trace element contents in the fermentation medium was conducted. Following 120 h of fed-batch fermentation, the accumulated final squalene yield in the transformed strain SQS-3626 reached 2.2 g/L.
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Farnesil Difosfato Farnesil Transferasa , Fermentación , Ácido Mevalónico , Regiones Promotoras Genéticas , Escualeno , Estramenopilos , Escualeno/metabolismo , Estramenopilos/genética , Estramenopilos/metabolismo , Ácido Mevalónico/metabolismo , Farnesil Difosfato Farnesil Transferasa/genética , Farnesil Difosfato Farnesil Transferasa/metabolismo , Ingeniería Metabólica/métodos , Clonación Molecular/métodosRESUMEN
Biosurfactants, synthesized by microorganisms, hold potential for various industrial and environmental applications due to their surface-active properties and biodegradability. Metabolic and genetic engineering strategies enhance biosurfactant production by modifying microbial pathways and genetics. Strategies include optimizing biosurfactant biosynthesis pathways, expanding substrate utilization, and improving stress responses. Genetic engineering allows customization of biosurfactant characteristics to meet industrial needs. Notable examples include engineering Pseudomonas aeruginosa for enhanced rhamnolipid production and creating synthetic biosurfactant pathways in non-native hosts like Escherichia coli. CRISPR-Cas9 technology offers precise tools for genetic manipulation, enabling targeted gene disruption and promoter optimization to enhance biosurfactant production efficiency. Synthetic promoters enable precise control over biosurfactant gene expression, contributing to pathway optimization across diverse microbial hosts. The future of biosurfactant research includes sustainable bio-processing, customized biosurfactant engineering, and integration of artificial intelligence and systems biology. Advances in genetic and metabolic engineering will enable tailor-made biosurfactants for diverse applications, with potential for industrial-scale production and commercialization. Exploration of untapped microbial diversity may lead to novel biosurfactants with unique properties, expanding the versatility and sustainability of biosurfactant-based solutions.
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Gene replacement therapies primarily rely on adeno-associated virus (AAV) vectors for transgene expression. However, episomal expression can decline over time due to vector loss or epigenetic silencing. CRISPR-based integration methods offer promise for long-term transgene insertion. While the development of transgene integration methods has made substantial progress, identifying optimal insertion loci remains challenging. Skeletal muscle is a promising tissue for gene replacement owing to low invasiveness of intramuscular injections, relative proportion of body mass, the multinucleated nature of muscle, and the potential for reduced adverse effects. Leveraging endogenous promoters in skeletal muscle, we evaluated two highly expressing loci using homology-independent targeted integration (HITI) to integrate reporter or therapeutic genes in mouse myoblasts and skeletal muscle tissue. We hijacked the muscle creatine kinase (Ckm) and myoglobin (Mb) promoters by co-delivering CRISPR-Cas9 and a donor plasmid with promoterless constructs encoding green fluorescent protein (GFP) or human Factor IX (hFIX). Additionally, we deeply profiled our genome and transcriptome outcomes from targeted integration and evaluated the safety of the proposed sites. This study introduces a proof-of-concept technology for achieving high-level therapeutic gene expression in skeletal muscle, with potential applications in targeted integration-based medicine and synthetic biology.
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Cadmium (Cd) toxicity significantly threatens agricultural productivity and food safety. Developing effective strategies to enhance plant tolerance to Cd stress is essential. This study investigates the synergistic effects of biochar (BC) and gibberellic acid (GA3) on mitigating Cd toxicity in maize (Zea mays), focusing on their impact on oxidative stress markers and antioxidant enzyme activities. Soil samples were collected from the Cholistan Institute of Desert Studies (CIDS) and analyzed for trace metal ions and other properties. Biochar was produced from fruit and vegetable waste, washed, washed, deashed, and mixed with 10 ppm GA3. FH-1036 hybrid maize seeds were sterilized and planted in pots containing soil with varying Cd levels (0, 8, and 16 mg Cd/kg soil). Twelve treatments were established, including control, GA3, BC, and their combinations under different Cd stress levels. Plants were irrigated to maintain 60% field capacity and harvested at the V10 growth stage. Hydrogen peroxide (H2O2) contents and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were measured in roots, stems, and leaves. Statistical analysis was performed using OriginPro 2021, with ANOVA and Fisher's LSD test used to determine significant differences. GA3 and BC treatments significantly reduced H2O2 levels in maize roots, stems and leaves under Cd stress. The combined treatment of GA3 + BC showed the most significant reduction in H2O2 levels across all plant parts, reducing root H2O2 by 50%, stem H2O2 by 55%, and leaf H2O2 by 53% under severe Cd stress (16 mg Cd/kg). SOD activity increased under non-stress conditions but decreased under Cd stress, with the highest activity observed in the combined treatment. POD activity followed a similar pattern, with GA3 + BC treatment resulting in the most significant increases under non-stress conditions and the least reductions under Cd stress. CAT activity showed substantial increases with GA3 + BC treatment, particularly under severe Cd stress, with a notable rise over the control. APX activity also exhibited enhancements with GA3 and BC treatments, especially in the combined treatment under various Cd stress levels. This study highlights the potential of combined BC and GA3 treatments in improving Cd stress tolerance in maize. Future research should focus on field trials and the long-term impacts of these treatments on crop productivity and soil health.
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Cadmio , Carbón Orgánico , Giberelinas , Zea mays , Giberelinas/metabolismo , Giberelinas/farmacología , Cadmio/toxicidad , Zea mays/efectos de los fármacos , Zea mays/metabolismo , Zea mays/crecimiento & desarrollo , Estrés Oxidativo/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Antioxidantes/metabolismo , Catalasa/metabolismo , Superóxido Dismutasa/metabolismo , Sinergismo Farmacológico , Peroxidasa/metabolismo , Contaminantes del Suelo/toxicidadRESUMEN
As an important global food crop, rice is damaged by a variety of piercing-sucking pests. Identifying a broad-spectrum promoter induced by the physical signal of sucking pests and applying it to transgenic breeding to mitigate the damage caused by different sucking pests will significantly improve the efficiency of our breeding. This study compared the transcriptome changes in two rice varieties under needle-wounding stress to investigate their differential responses to mechanical damage. The results showed that the insect-susceptible variety TN1 exhibited more differentially expressed genes (DEGs) and greater changes in expression levels after needle treatment, indicating a more active internal gene regulatory network. GO and KEGG enrichment analysis further revealed that TN1 not only exhibited changes in genes related to the extracellular environment, but also mobilized more genes associated with stress response and defense. By screening the differentially expressed genes, we identified two promoters (P1 and P2) with inducible expression characteristics in both the resistant and susceptible rice varieties. These promoters were able to effectively drive the expression of the insect resistance gene OsLecRK1* and enhance the resistance of transgenic plants against the brown planthopper. This study provides promoter resources for the development of insect-resistant transgenic crops.
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Regulación de la Expresión Génica de las Plantas , Oryza , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Oryza/genética , Oryza/parasitología , Plantas Modificadas Genéticamente/genética , Animales , Clonación Molecular/métodos , Hemípteros/genética , Proteínas de Plantas/genética , Transcriptoma , Perfilación de la Expresión GénicaRESUMEN
INTRODUCTION: Social network-based testing approaches (SNAs) encourage individuals ("test promoters") to motivate sexual partners and/or those in their social networks to test for HIV. We conducted a systematic review to examine the effectiveness, acceptability and cost-effectiveness of SNA. METHODS: We searched five databases from January 2010 to May 2023, and included studies that compared SNA with non-SNA. We used random-effects meta-analysis to combine effect estimates. Certainty was assessed using the GRADE approach. RESULTS: We identified 47 studies. SNA may increase uptake of HIV testing compared to non-SNA (RR 2.04, 95% CI: 1.06-3.95, Low certainty). The proportion of first-time testers was probably higher among partners or social contacts of test promoters using SNA compared to non-SNA (RR 1.49, 95% CI: 1.22-1.81, Moderate certainty). The proportion of people who tested positive for HIV may be higher among partners or social contacts of test promoters using SNA compared to non-SNA (RR 1.84, 95% CI: 1.01-3.35, Low certainty). There were no reports of any adverse events or harms associated with SNA. Based on six cost-effectiveness studies, SNA was generally cheaper per person tested and per person diagnosed compared to non-SNA. Based on 23 qualitative studies, SNA is likely to be acceptable to a variety of populations. DISCUSSION: Our review collated evidence for SNA to HIV testing covering the key populations and the general population who may benefit from HIV testing. We summarized evidence for the effectiveness, acceptability and cost-effectiveness of different models of SNA. While we did not identify an ideal model of SNA that could be immediately scaled up, for each setting and population targeted, we recommend various implementation considerations as our meta-analysis showed the effectiveness might differ due to factors which include the testing modality (i.e. use of HIV self-testing), type of test promoters, long or short duration of recruitment and use of financial incentives. CONCLUSIONS: Social network-based approaches may enhance HIV testing uptake, increase the proportion of first-time testers and those testing positive for HIV. Heterogeneity among studies highlights the need for context-specific adaptations, but the overall positive impact of SNA on HIV testing outcomes could support its integration into existing HIV testing services.
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Infecciones por VIH , Prueba de VIH , Humanos , Infecciones por VIH/diagnóstico , Prueba de VIH/métodos , Análisis Costo-Beneficio , Red Social , Aceptación de la Atención de Salud/estadística & datos numéricos , Apoyo Social , Parejas SexualesRESUMEN
DNA is the macromolecule responsible for storing the genetic information of a cell and it has intrinsic properties such as deformability, stability and curvature. DNA Curvature plays an important role in gene transcription and, consequently, in the subsequent production of proteins, a fundamental process of cells. With recent advances in bioinformatics and theoretical biology, it became possible to analyze and understand the involvement of DNA Curvature as a discriminatory characteristic of gene-promoting regions. These regions act as sites where RNAp (ribonucleic acid-polymerase) binds to initiate transcription. This review aims to describe the formation of Curvature, as well as highlight its importance in predicting promoters. Furthermore, this article provides the potential of DNA Curvature as a distinguishing feature for promoter prediction tools, as well as outlining the calculation procedures that have been described by other researchers. This work may support further studies directed towards the enhancement of promoter prediction software.
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ADN , Conformación de Ácido Nucleico , Regiones Promotoras Genéticas , ADN/genética , HumanosRESUMEN
This study facilitates design of expression vectors and lentivirus tools for gene editing of Atlantic salmon. We have characterized widely used heterologous promoters and novel endogenous promoters in Atlantic salmon cells. We used qPCR to evaluate the activity of several U6 promoters for sgRNA expression, including human U6 (hU6), tilapia U6 (tU6), mouse U6 (mU6), zebrafish U6 (zU6), Atlantic salmon U6 (sU6), medaka U6 (medU6), and fugu U6 (fU6) promoters. We also evaluated several polymerase type II (pol II) promoters by luciferase assay. Our results showed that hU6 and tU6 promoters were the most active among all the tested U6 promoters, and heterologous promoters (CMV, hEF1α core) had higher activity compared to endogenous Atlantic salmon promoters sHSP8, sNUC3L, sEF1α. Among endogenous pol II promoters, sEF1α and sHSP8 displayed higher activity than sNUC3L, sHSP703, sHSP7C, sXRCC1L, and sETF. We observed that extending the promoter sequence to include the region up to the start codon (ATG) resulted in a significant increase in expression efficiency for sNUC3L and sEF1α. We also show that mutating the PRDM1 motif will significantly decrease the activity of the sEF1α promoter. The presence of the PRDM1 motif in sHSP8 promoter was also associated with relatively high expression compared to the promoters that naturally lacked this motif, such as sNUC3L. We speculate that this short sequence might be included in other promoters to further enhance the promoter activity, but further experiments are needed to confirm this. Our findings provide valuable insights into the activity of different promoters in Atlantic salmon cells and can be used to facilitate further transgenic studies and improve the efficiency of transgene expression in Atlantic salmon.
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Cyanobacteria show promise as hosts for whole-cell biocatalysis. Their photoautotrophic metabolism can be leveraged for a sustainable production process. Despite advancements, performance still lags behind heterotrophic hosts. A key challenge is the limited ability to overexpress recombinant enzymes, which also hinders their biocatalytic efficiency. To address this, we generated large-scale expression libraries and developed a high-throughput method combining fluorescence-activated cell sorting (FACS) and deep sequencing in Synechocystis sp. PCC 6803 (Syn. 6803) to screen and optimize its genetic background. We apply this approach to enhance expression and biocatalyst performance for three enzymes: the ketoreductase LfSDR1M50, enoate reductase YqjM, and Baeyer-Villiger monooxygenase (BVMO) CHMOmut. Diverse genetic combinations yielded significant improvements: optimizing LfSDR1M50 expression showed a 17-fold increase to 39.2 U gcell dry weight (CDW)-1. In vivo activity of Syn. YqjM was improved 16-fold to 58.7 U gCDW-1 and, for Syn. CHMOmut, a 1.5-fold increase to 7.3 U gCDW-1 was achieved by tailored genetic design. Thus, this strategy offers a pathway to optimize cyanobacteria as expression hosts, paving the way for broader applications in other cyanobacteria strains and larger libraries.
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Promoters, which are short (50-1500 base-pair) in DNA regions, have emerged to play a critical role in the regulation of gene transcription. Numerous dangerous diseases, likewise cancer, cardiovascular, and inflammatory bowel diseases, are caused by genetic variations in promoters. Consequently, the correct identification and characterization of promoters are significant for the discovery of drugs. However, experimental approaches to recognizing promoters and their strengths are challenging in terms of cost, time, and resources. Therefore, computational techniques are highly desirable for the correct characterization of promoters from unannotated genomic data. Here, we designed a powerful bi-layer deep-learning based predictor named "PROCABLES", which discriminates DNA samples as promoters in the first-phase and strong or weak promoters in the second-phase respectively. The proposed method utilizes five distinct features, such as word2vec, k-spaced nucleotide pairs, trinucleotide propensity-based features, trinucleotide composition, and electron-ion interaction pseudopotentials, to extract the hidden patterns from the DNA sequence. Afterwards, a stacked framework is formed by integrating a convolutional neural network (CNN) with bidirectional long-short-term memory (LSTM) using multi-view attributes to train the proposed model. The PROCABLES model achieved an accuracy of 0.971 and 0.920 and the MCC 0.940 and 0.840 for the first and second-layer using the ten-fold cross-validation test, respectively. The predicted results anticipate that the proposed PROCABLES protocol outperformed the advanced computational predictors targeting promoters and their types. In summary, this research will provide useful hints for the recognition of large-scale promoters in particular and other DNA problems in general.
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Aprendizaje Profundo , Regiones Promotoras Genéticas , Humanos , Redes Neurales de la Computación , Biología Computacional/métodos , ADN/genética , ADN/químicaRESUMEN
Synonymous codons were originally viewed as interchangeable, with no phenotypic consequences. However, substantial evidence has now demonstrated that synonymous substitutions can perturb a variety of gene expression and protein homeostasis mechanisms, including translational efficiency, translational fidelity, and cotranslational folding of the encoded protein. To date, most studies of synonymous codon-derived perturbations have focused on effects within a single gene. Here, we show that synonymous codon substitutions made far within the coding sequence of Escherichia coli plasmid-encoded chloramphenicol acetyltransferase (cat) can significantly increase expression of the divergent upstream tetracycline resistance gene, tetR. In four out of nine synonymously recoded cat sequences tested, expression of the upstream tetR gene was significantly elevated due to transcription of a long antisense RNA (asRNA) originating from a transcription start site within cat. Surprisingly, transcription of this asRNA readily bypassed the native tet transcriptional repression mechanism. Even more surprisingly, accumulation of the TetR protein correlated with the level of asRNA, rather than total tetR RNA. These effects of synonymous codon substitutions on transcription and translation of a neighboring gene suggest that synonymous codon usage in bacteria may be under selection to both preserve the amino acid sequence of the encoded gene and avoid DNA sequence elements that can significantly perturb expression of neighboring genes. Avoiding such sequences may be especially important in plasmids and prokaryotic genomes, where genes and regulatory elements are often densely packed. Similar considerations may apply to the design of genetic circuits for synthetic biology applications.
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Cloranfenicol O-Acetiltransferasa , Codón , Escherichia coli , Biosíntesis de Proteínas , ARN sin Sentido , Transcripción Genética , ARN sin Sentido/genética , ARN sin Sentido/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Codón/genética , Regulación Bacteriana de la Expresión Génica , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , Mutación SilenciosaRESUMEN
Currently used organic coatings for the protection of bronze sculptures have a relatively short lifespan as a consequence of strict requirements of conservation ethics, which limit the selection of coatings. For that reason, enhancement of the corrosion protection level and durability of appropriate coatings is needed. The aim of this work was to examine if corrosion protection of bronze by selected acrylic and polyurethane coatings could be improved by using two phosphonic acids, 16-phosphonohexadecanoic acid (COOH-PA) and 12-aminododecylphosphonic acid (NH2-PA). Electrochemical measurements (linear polarization and electrochemical impedance spectroscopy, EIS) were performed to gain an insight into the influence of these phosphonic acids on the performance of the coatings during a two-week exposure to artificial acid rain and a three-month outdoor exposure. Besides the influence on the corrosion protection level, the influence on the coating adhesion was examined as well. A pull-off test clearly confirmed that the studied phosphonic acids act as adhesion promoters of both polyurethane and acrylic coatings, while electrochemical studies revealed improvements in corrosion protection levels, especially in the case of the acrylic coating Paraloid B72.
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The objective of this study was to evaluate the effects of yeast products (YP) and essential oils (EO) in total or partial replacement to in-feed antibiotic protocols (growth promoter and prophylactic), both in recommended doses and in overdose of prophylactic antibiotics (PA), on growth performance, and diarrhea incidence in the growing-finishing pigs; and fecal microbiota in market hogs. Four hundred pigs (20.36â ±â 2.64 kg) were assigned to five treatments in a randomized block design: diets with prophylactic and growth promoter antibiotics (ANT); ANT with 30% more PA (ANT+30); diets with less PA and YP (ANT+Y); diets with less PA, YP and EO (ANT+Y+EO); and antibiotics-free diets with YP and EO (Y+EO). The content of the active components of the YP was 60% purified ß-1,3/1,6-glucans extracted from Saccharomyces cerevisiae yeast (Macrogard), 20% functional water-soluble MOS (HyperGen), and 18% MOS, extracted from Saccharomyces cerevisiae yeast (ActiveMOS). From 0 to 14 d, pigs of the ANT+30, ANT+Y, and ANT+Y+EO treatments showed a greater body weight (BW) and average daily gain (ADG) compared to pigs from the Y+EO group. From 14 to 35 d, pigs of ANT+30 and ANT+Y+EO treatments were heavier than Y+EO group. At 105 d, ANT pigs had a higher BW than the Y+EO group. For the entire period, ADG of ANT pigs was greater, and feed conversion ratio better than Y+EO pigs. From 0 to 35 d, pigs of the Y+EO treatment showed a higher diarrhea incidence compared to pigs of the other groups. From 49 to 70 d, ANT+Y and ANT+Y+EO treatments showed a lower diarrhea incidence than Y+EO group, which remained the case during the overall period. At 105 d, the alpha diversity of fecal microbiota by Shannon Entropy was lower in ANT, ANT+30, and Y+EO groups than observed for ANT+Y+EO group. The abundance of Firmicutes phylum and Firmicutes/Bacteroidetes ratio was higher in ANT than in ANT+Y+EO pigs. Proteobacteria phylum abundance in ANT+Y+EO was higher than ANT, ANT+Y, and Y+EO. Peptostreptococcaceae family abundance was higher in ANT, ANT+30, and ANT+Y groups than in ANT+Y+EO and Y+EO groups. ANT+Y+EO and Y+EO groups show a lower abundance of SMB53 genus than ANT and ANT+30 groups. In conclusion, the use of YP and EO, in partial replacement to the in-feed antibiotic protocols, does not reduce the growth performance, can replace antibiotic growth promotors, and reduce the in-feed use of PA in growing-finishing pigs. The use of YP and EO, together with PA, increases the microbial diversity, despite having important genera for weight gain in less abundance. Overdose of PA does not improve growth performance and reduces microbial diversity, which does not characterize it as an efficient preventive protocol.
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Aging is a process of time-associated depletion in the physiological functions, essential for the survival and reproducibility of living beings. Some age-related disorders can be successfully controlled with some biomedical techniques or pharmaceutical approaches. There are some precise remedies that demonstrate conspicuous promise in the preclinical and clinical setup of extending lifespan or enhancing health by altering natural senescence. The sirtuin family of proteins is one of the most favorable targets for antiaging strategies. Sirtuins were initially identified as transcription repressors in yeast, but today they are known to exist in bacteria and eukaryotes, as well as humans. The SIRT (1-7) family of proteins in humans is made up of seven members, each of which has either mono-ADP ribosyl transferase or deacetylase activity. Researchers suggest that sirtuins are essential for cell metabolism and play a major role in how cells react to various stimuli, such as oxidative or genotoxic stress. A healthy lifestyle, which includes exercise and a balanced diet, has been demonstrated to impact health span by adjusting the levels of sirtuins, suggesting the involvement of sirtuins in extending human longevity. The hunt for sirtuin activators is among the most extensive and comprehensive research subjects in the present scenario. Some optimism has been generated to investigate antiaging therapies by natural compounds, such as curcumin and others. This review article highlights the role of sirtuins in native senescence and their primordial roles in the progression of several life-threatening diseases. Further, it also provides recent information on the sirtuin activators and inhibitors and their therapeutic benefits.
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Envejecimiento , Sirtuinas , Humanos , Sirtuinas/metabolismo , Envejecimiento/metabolismo , Animales , Senescencia Celular , LongevidadRESUMEN
DNA chains with sequential guanine (G) repeats can lead to the formation of G-quadruplexes (G4), which are found in functional DNA and RNA regions like telomeres and oncogene promoters. The development of molecules with adequate structural features to selectively stabilize G4 structures can counteract cell immortality, highly described for cancer cells, and also downregulate transcription events underlying cell apoptosis and/or senescence processes. We describe here, the efficiency of four highly charged porphyrins-phosphonium conjugates to act as G4 stabilizing agents. The spectrophotometric results allowed to select the conjugates P2-PPh3 and P3-PPh3 as the most promising ones to stabilize selectively G4 structures. Molecular dynamics simulation experiments were performed and support the preferential binding of P2-PPh3 namely to MYC and of P3-PPh3 to KRAS. The ability of both ligands to block the activity of Taq polymerase was confirmed and also their higher cytotoxicity against the two melanoma cell lines A375 and SK-MEL-28 than to immortalized skin keratinocytes. Both ligands present efficient cellular uptake, nuclear co-localization and high ability to generate 1O2 namely when interacting with G4 structure. The obtained data points the synthesized porphyrins as promising ligands to be used in a dual approach that can combine G4 stabilization and Photodynamic therapy (PDT).
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G-Cuádruplex , Porfirinas , Telómero , G-Cuádruplex/efectos de los fármacos , Porfirinas/química , Porfirinas/farmacología , Humanos , Telómero/química , Línea Celular Tumoral , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Simulación de Dinámica Molecular , Ligandos , OncogenesRESUMEN
A group of N-phenylbenzofuran-2-carboxamide and N-phenylbenzo[b]thiophene-2-carboxamide derivatives were designed and synthesized as a novel class of Aß42 aggregation modulators. In the thioflavin-T based fluorescence aggregation kinetics study, compounds 4 a, 4 b, 5 a and 5 b possessing a methoxyphenol pharmacophore were able to demonstrate concentration dependent inhibition of Aß42 aggregation with maximum inhibition of 54 % observed for compound 4 b. In contrast, incorporation of a 4-methoxyphenyl ring in compounds 4 d and 5 d led to a significant increase in Aß42 fibrillogenesis demonstrating their ability to accelerate Aß42 aggregation. Compound 4 d exhibited 2.7-fold increase in Aß42 fibrillogenesis when tested at the maximum concentration of 25â µM. These results were further confirmed by electron microscopy studies which demonstrates the ability of compounds 4 a, 4 b, 4 d, 5 a, 5 b and 5 d to modulate Aß42 fibrillogenesis. Compounds 5 a and 5 b provided significant neuroprotection to mouse hippocampal neuronal HT22 cells against Aß42-induced cytotoxicity. Molecular docking studies suggest that the orientation of the bicyclic aromatic rings (either benzofuran or benzo[b]thiophene) plays a major role in moderating their ability to either inhibit or accelerate Aß42 aggregation. Our findings support the application of these novel derivatives as pharmacological tools to study the mechanisms of Aß42 aggregation.
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The greatest challenges that organisms face today are effective responses or detection of life-threatening environmental changes due to an obvious semblance of stress and metabolic fluctuations. These are associated with different pathological conditions among which cancer is most important. Sirtuins (SIRTs; NAD+-dependent enzymes) are versatile enzymes with diverse substrate preferences, cellular locations, crucial for cellular processes and pathological conditions. This article describes in detail the distinct roles of SIRT isoforms, unveiling their potential as either cancer promoters or suppressors and also explores how both natural and synthetic compounds influence the SIRT function, indicating promise for therapeutic applications. We also discussed the inhibitors/activators tailored to specific SIRTs, holding potential for diseases lacking effective treatments. It may uncover the lesser-studied SIRT isoforms (e.g., SIRT6, SIRT7) and their unique functions. This article also offers a comprehensive overview of SIRTs, linking them to a spectrum of diseases and highlighting their potential for targeted therapies, combination approaches, disease management, and personalized medicine. We aim to contribute to a transformative era in healthcare and innovative treatments by unraveling the intricate functions of SIRTs.
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Genomic integration is commonly used to engineer stable production hosts. However, so far, for many microbial workhorses, only a few integration sites have been characterized, thereby restraining advanced strain engineering that requires multiple insertions. Here, we report on the identification of novel genomic integration sites, so-called landing pads, for Pseudomonas putida KT2440. We identified genomic regions with constant expression patterns under diverse experimental conditions by using RNA-Seq data. Homologous recombination constructs were designed to insert heterologous genes into intergenic sites in these regions, allowing condition-independent gene expression. Ten potential landing pads were characterized using four different msfGFP expression cassettes. An insulated probe sensor was used to study locus-dependent effects on recombinant gene expression, excluding genomic read-through of flanking promoters under changing cultivation conditions. While the reproducibility of expression in the landing pads was very high, the msfGFP signals varied strongly between the different landing pads, confirming a strong influence of the genomic context. To showcase that the identified landing pads are also suitable candidates for heterologous gene expression in other Pseudomonads, four equivalent landing pads were identified and characterized in Pseudomonas taiwanensis VLB120. This study shows that genomic "hot" and "cold" spots exist, causing strong promoter-independent variations in gene expression. This highlights that the genomic context is an additional parameter to consider when designing integrable genomic cassettes for tailored heterologous expression. The set of characterized genomic landing pads presented here further increases the genetic toolbox for deep metabolic engineering in Pseudomonads.