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1.
EMBO Rep ; 25(5): 2220-2238, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38600345

RESUMO

Perturbation of protein phosphorylation represents an attractive approach to cancer treatment. Besides kinase inhibitors, protein phosphatase inhibitors have been shown to have anti-cancer activity. A prime example is the small molecule LB-100, an inhibitor of protein phosphatases 2A/5 (PP2A/PP5), enzymes that affect cellular physiology. LB-100 has proven effective in pre-clinical models in combination with immunotherapy, but the molecular underpinnings of this synergy remain understood poorly. We report here a sensitivity of the mRNA splicing machinery to phosphorylation changes in response to LB-100 in colorectal adenocarcinoma. We observe enrichment for differentially phosphorylated sites within cancer-critical splicing nodes of U2 snRNP, SRSF and hnRNP proteins. Altered phosphorylation endows LB-100-treated colorectal adenocarcinoma cells with differential splicing patterns. In PP2A-inhibited cells, over 1000 events of exon skipping and intron retention affect regulators of genomic integrity. Finally, we show that LB-100-evoked alternative splicing leads to neoantigens that are presented by MHC class 1 at the cell surface. Our findings provide a potential explanation for the pre-clinical and clinical observations that LB-100 sensitizes cancer cells to immune checkpoint blockade.


Assuntos
Neoplasias do Colo , Splicing de RNA , Humanos , Processamento Alternativo/efeitos dos fármacos , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Inibidores Enzimáticos/farmacologia , Fosforilação , Proteína Fosfatase 2/metabolismo , Splicing de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Piperazinas/farmacologia
2.
Cancer Sci ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013843

RESUMO

In our previous study, we found that small ubiquitin-related modifier (SUMO)-activating enzyme ubiquitin-associated-2 domain (UBA2) was upregulated in hepatocellular carcinoma (HCC) patients who were insensitive to chemoembolization. In this study, we aimed to investigate the role of UBA2 in HCC progression. Three cohorts were used to evaluate the efficacy of UBA2 as a prognostic factor for HCC. Our results indicated that UBA2 was associated with aggressive clinical behaviors and was a strong indicator of poor prognosis in HCC. In vitro experiments demonstrated that UBA2 accelerated cell growth, invasion, and migration. These results were further supported by in vivo experiments. RNA-sequencing analysis indicated NQO1 as a target of UBA2, with its levels altering following UBA2 manipulation. The results were verified by western blotting (WB) and quantitative PCR. The SUMOplot Analysis Program predicted lysine residue K240 as a modification target of UBA2, which was confirmed by immunoprecipitation (IP) assays. Subsequent mutation of NQO1 at K240 in HCC cell lines and functional assays revealed the significance of this modification. In addition, the oncogenic effect of UBA2 could be reversed by the SUMO inhibitor ML792 in vivo and in vitro. In conclusion, our study elucidated the regulatory mechanism of UBA2 in HCC and suggested that the SUMO inhibitor ML792 may be an effective combinatory treatment for patients with aberrant UBA2 expression.

3.
Plant Biotechnol J ; 22(8): 2145-2156, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38511622

RESUMO

Soybean is a typical short-day crop, and most commercial soybean cultivars are restricted to a relatively narrow range of latitudes due to photoperiod sensitivity. Photoperiod sensitivity hinders the utilization of soybean germplasms across geographical regions. When grown in temperate regions, tropical soybean responds to prolonged day length by increasing the vegetative growth phase and delaying flowering and maturity, which often pushes the harvest window past the first frost date. In this study, we used CRISPR/LbCas12a to edit a North American subtropical soybean cultivar named 06KG218440 that belongs to maturity group 5.5. By designing one gRNA to edit the nuclear localization signal (NLS) regions of both E1 and E1Lb, we created a series of new germplasms with shortened flowering time and time to maturity and determined their favourable latitudinal zone for cultivation. The novel partial function alleles successfully achieve yield and early maturity trade-offs and exhibit good agronomic traits and high yields in temperate regions. This work offers a straightforward editing strategy to modify subtropical and tropical soybean cultivars for temperate growing regions, a strategy that could be used to enrich genetic diversity in temperate breeding programmes and facilitate the introduction of important crop traits such as disease tolerance or high yield.


Assuntos
Edição de Genes , Glycine max , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Glycine max/metabolismo , Edição de Genes/métodos , Sinais de Localização Nuclear , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Sistemas CRISPR-Cas
4.
J Transl Med ; 22(1): 727, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103918

RESUMO

BACKGROUND: Vascular dysregulation is one of the major risk factors of glaucoma, and endothelin-1 (ET-1) may have a role in the pathogenesis of vascular-related glaucoma. Fruit extract from Lycium Barbarum (LB) exhibits anti-ageing and multitarget mechanisms in protecting retinal ganglion cells (RGC) in various animal models. To investigate the therapeutic efficacy of LB glycoproteins (LbGP) in ET-1 induced RGC degeneration, LbGP was applied under pre- and posttreatment conditions to an ET-1 mouse model. Retina structural and functional outcomes were characterised using clinical-based techniques. METHODS: Adult C57BL/6 mice were randomly allocated into four experimental groups, namely vehicle control (n = 9), LbGP-Pretreatment (n = 8), LbGP-Posttreatment (day 1) (n = 8) and LbGP-Posttreatment (day 5) (n = 7). Oral administration of LbGP 1 mg/Kg or PBS for vehicle control was given once daily. Pre- and posttreatment (day 1 or 5) were commenced at 1 week before and 1 or 5 days after intravitreal injections, respectively, and were continued until postinjection day 28. Effects of treatment on retinal structure and functions were evaluated using optical coherence tomography (OCT), doppler OCT and electroretinogram measurements at baseline, post-injection days 10 and 28. RGC survival was evaluated by using RBPMS immunostaining on retinal wholemounts. RESULTS: ET-1 injection in vehicle control induced transient reductions in arterial flow and retinal functions, leading to significant RNFL thinning and RGC loss at day 28. Although ET-1 induced a transient loss in blood flow or retinal functions in all LbGP groups, LbGP treatments facilitated better restoration of retinal flow and retinal functions as compared with the vehicle control. Also, all three LbGP treatment groups (i.e. pre- and posttreatments from days 1 or 5) significantly preserved thRNFL thickness and RGC densities. No significant difference in protective effects was observed among the three LbGP treatment groups. CONCLUSION: LbGP demonstrated neuroprotective effects in a mouse model of ET-1 induced RGC degeneration, with treatment applied either as a pretreatment, immediate or delayed posttreatment. LbGP treatment promoted a better restoration of retinal blood flow, and protected the RNFL, RGC density and retinal functions. This study showed the translational potential of LB as complementary treatment for glaucoma management.


Assuntos
Endotelina-1 , Camundongos Endogâmicos C57BL , Neuroproteção , Células Ganglionares da Retina , Animais , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/metabolismo , Endotelina-1/metabolismo , Neuroproteção/efeitos dos fármacos , Eletrorretinografia , Lycium/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/patologia , Tomografia de Coerência Óptica , Masculino , Camundongos , Degeneração Neural/patologia , Degeneração Neural/tratamento farmacológico
5.
Microb Pathog ; 192: 106686, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38750775

RESUMO

Limosilactobacillus fermentum is an isolate obtained from oral gingival samples of healthy human individuals. The whole genome of Lb. fermentum GD5MG is composed of a circular DNA molecule containing 1,834,134 bp and exhibits a GC content of 52.80 %. The sequencing effort produced 38.6 million reads, each 150 bp in length, resulting in a sequencing depth of 2912.48x. Our examination unveiled a total of 1961 protein-coding genes, 27 rRNA genes, 24 tRNA genes, 3 non-coding RNA genes, and 63 pseudogenes with the use of gene annotations in NCBI Prokaryotic Genome Annotation tool. RAST revealed 1863 coding genes distributed across 209 subsystems, with a predominant involvement in amino acid, carbohydrate, and protein metabolism. Phylogenetic analysis infers that the Lb. fermentum GD5MG shares 281 gene clusters. Furthermore, the genome features showed a single CRISPR locus of 45 bp in length. Three genes associated with adhesion ability (strA, dltD, and dltA) and 26 genes related to acid tolerance, digestive enzyme secretion, and bile salt resistance were identified. Numerous genes associated with oral probiotic properties, comprising adhesion, acid and bile salt tolerance, oxidative stress tolerance, and sugar metabolism, were identified in the genome. Our findings shed light on the genomic characteristics of Lb. fermentum GD5MG, which are probable probiotics with functional benefits in humans.


Assuntos
Genoma Bacteriano , Limosilactobacillus fermentum , Filogenia , Probióticos , Limosilactobacillus fermentum/genética , Genoma Bacteriano/genética , Humanos , Família Multigênica , Anotação de Sequência Molecular , Composição de Bases/genética , Proteínas de Bactérias/genética , Análise de Sequência de DNA , Aderência Bacteriana/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Pseudogenes/genética , DNA Bacteriano/genética , Genes Bacterianos/genética
6.
Bioorg Med Chem Lett ; 110: 129852, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38925524

RESUMO

The global outbreak of the COVID-19 pandemic caused by the SARS-CoV-2 virus had led to profound respiratory health implications. This study focused on designing organoselenium-based inhibitors targeting the SARS-CoV-2 main protease (Mpro). The ligand-binding pathway sampling method based on parallel cascade selection molecular dynamics (LB-PaCS-MD) simulations was employed to elucidate plausible paths and conformations of ebselen, a synthetic organoselenium drug, within the Mpro catalytic site. Ebselen effectively engaged the active site, adopting proximity to H41 and interacting through the benzoisoselenazole ring in a π-π T-shaped arrangement, with an additional π-sulfur interaction with C145. In addition, the ligand-based drug design using the QSAR with GFA-MLR, RF, and ANN models were employed for biological activity prediction. The QSAR-ANN model showed robust statistical performance, with an r2training exceeding 0.98 and an RMSEtest of 0.21, indicating its suitability for predicting biological activities. Integration the ANN model with the LB-PaCS-MD insights enabled the rational design of novel compounds anchored in the ebselen core structure, identifying promising candidates with favorable predicted IC50 values. The designed compounds exhibited suitable drug-like characteristics and adopted an active conformation similar to ebselen, inhibiting Mpro function. These findings represent a synergistic approach merging ligand and structure-based drug design; with the potential to guide experimental synthesis and enzyme assay testing.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Desenho de Fármacos , Isoindóis , Aprendizado de Máquina , Simulação de Dinâmica Molecular , Compostos Organosselênicos , Inibidores de Proteases , Relação Quantitativa Estrutura-Atividade , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Compostos Organosselênicos/síntese química , Isoindóis/química , Isoindóis/farmacologia , Isoindóis/síntese química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Inibidores de Proteases/síntese química , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Humanos , Azóis/química , Azóis/farmacologia , Azóis/síntese química , COVID-19/virologia , Domínio Catalítico
7.
Environ Sci Technol ; 58(8): 3895-3907, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38356175

RESUMO

Volatilization of lower-chlorinated polychlorinated biphenyls (LC-PCBs) from sediment poses health threats to nearby communities and ecosystems. Biodegradation combined with black carbon (BC) materials is an emerging bioaugmentation approach to remove PCBs from sediment, but development of aerobic biofilms on BC for long-term, sustained LC-PCBs remediation is poorly understood. This work aimed to characterize the cell enrichment and activity of biphenyl- and benzoate-grown Paraburkholderia xenovorans strain LB400 on various BCs. Biphenyl dioxygenase gene (bphA) abundance on four BC types demonstrated corn kernel biochar hosted at least 4 orders of magnitude more attached cells per gram than other feedstocks, and microscopic imaging revealed the attached live cell fraction was >1.5× more on corn kernel biochar than GAC. BC characteristics (i.e., sorption potential, pore size, pH) appear to contribute to cell attachment differences. Reverse transcription qPCR indicated that BC feedstocks significantly influenced bphA expression in attached cells. The bphA transcript-per-gene ratio of attached cells was >10-fold more than suspended cells, confirmed by transcriptomics. RNA-seq also demonstrated significant upregulation of biphenyl and benzoate degradation pathways on attached cells, as well as revealing biofilm formation potential/cell-cell communication pathways. These novel findings demonstrate aerobic PCB-degrading cell abundance and activity could be tuned by adjusting BC feedstocks/attributes to improve LC-PCBs biodegradation potential.


Assuntos
Compostos de Bifenilo , Burkholderiaceae , Carvão Vegetal , Bifenilos Policlorados , Benzoatos , Biodegradação Ambiental , Carbono , Ecossistema , Bifenilos Policlorados/metabolismo , Dioxigenases/química , Dioxigenases/metabolismo
8.
Appl Microbiol Biotechnol ; 108(1): 361, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837050

RESUMO

Lactobacillus delbrueckii subsp. bulgaricus and Lactiplantibacillus plantarum are two lactic acid bacteria (LAB) widely used in the food industry. The objective of this work was to assess the resistance of these bacteria to freeze- and spray-drying and study the mechanisms involved in their loss of activity. The culturability and acidifying activity were measured to determine the specific acidifying activity, while membrane integrity was studied by flow cytometry. The glass transitions temperature and the water activity of the dried bacterial suspensions were also determined. Fourier transform infrared (FTIR) micro-spectroscopy was used to study the biochemical composition of cells in an aqueous environment. All experiments were performed after freezing, drying and storage at 4, 23 and 37 °C. The results showed that Lb. bulgaricus CFL1 was sensitive to osmotic, mechanical, and thermal stresses, while Lpb. plantarum WCFS1 tolerated better the first two types of stress but was more sensitive to thermal stress. Moreover, FTIR results suggested that the sensitivity of Lb. bulgaricus CFL1 to freeze-drying could be attributed to membrane and cell wall degradation, whereas changes in nucleic acids and proteins would be responsible of heat inactivation of both strains associated with spray-drying. According to the activation energy values (47-85 kJ/mol), the functionality loss during storage is a chemically limited reaction. Still, the physical properties of the glassy matrix played a fundamental role in the rates of loss of activity and showed that a glass transition temperature 40 °C above the storage temperature is needed to reach good preservation during storage. KEY POINTS: • Specific FTIR bands are proposed as markers of osmotic, mechanic and thermal stress • Lb. bulgaricus CFL1 was sensitive to all three stresses, Lpb. plantarum WCFS1 to thermal stress only • Activation energy revealed chemically limited reactions ruled the activity loss in storage.


Assuntos
Liofilização , Liofilização/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Secagem por Atomização , Viabilidade Microbiana , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/fisiologia , Lactobacillus delbrueckii/metabolismo , Lactobacillus delbrueckii/fisiologia , Lactobacillales/metabolismo , Lactobacillales/fisiologia , Dessecação
9.
Biol Res ; 57(1): 12, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561836

RESUMO

BACKGROUND: Bacterial aromatic degradation may cause oxidative stress. The long-chain flavodoxin FldX1 of Paraburkholderia xenovorans LB400 counteracts reactive oxygen species (ROS). The aim of this study was to evaluate the protective role of FldX1 in P. xenovorans LB400 during the degradation of 4-hydroxyphenylacetate (4-HPA) and 3-hydroxyphenylacetate (3-HPA). METHODS: The functionality of FldX1 was evaluated in P. xenovorans p2-fldX1 that overexpresses FldX1. The effects of FldX1 on P. xenovorans were studied measuring growth on hydroxyphenylacetates, degradation of 4-HPA and 3-HPA, and ROS formation. The effects of hydroxyphenylacetates (HPAs) on the proteome (LC-MS/MS) and gene expression (qRT-PCR) were quantified. Bioaugmentation with strain p2-fldX1 of 4-HPA-polluted soil was assessed, measuring aromatic degradation (HPLC), 4-HPA-degrading bacteria, and plasmid stability. RESULTS: The exposure of P. xenovorans to 4-HPA increased the formation of ROS compared to 3-HPA or glucose. P. xenovorans p2-fldX1 showed an increased growth on 4-HPA and 3-HPA compared to the control strain WT-p2. Strain p2-fldX1 degraded faster 4-HPA and 3-HPA than strain WT-p2. Both WT-p2 and p2-fldX1 cells grown on 4-HPA displayed more changes in the proteome than cells grown on 3-HPA in comparison to glucose-grown cells. Several enzymes involved in ROS detoxification, including AhpC2, AhpF, AhpD3, KatA, Bcp, CpoF1, Prx1 and Prx2, were upregulated by hydroxyphenylacetates. Downregulation of organic hydroperoxide resistance (Ohr) and DpsA proteins was observed. A downregulation of the genes encoding scavenging enzymes (katE and sodB), and gstA and trxB was observed in p2-fldX1 cells, suggesting that FldX1 prevents the antioxidant response. More than 20 membrane proteins, including porins and transporters, showed changes in expression during the growth of both strains on hydroxyphenylacetates. An increased 4-HPA degradation by recombinant strain p2-fldX1 in soil microcosms was observed. In soil, the strain overexpressing the flavodoxin FldX1 showed a lower plasmid loss, compared to WT-p2 strain, suggesting that FldX1 contributes to bacterial fitness. Overall, these results suggest that recombinant strain p2-fldX1 is an attractive bacterium for its application in bioremediation processes of aromatic compounds. CONCLUSIONS: The long-chain flavodoxin FldX1 improved the capability of P. xenovorans to degrade 4-HPA in liquid culture and soil microcosms by protecting cells against the degradation-associated oxidative stress.


Assuntos
Burkholderia , Burkholderiaceae , Flavodoxina , Gliceraldeído/análogos & derivados , Fenilacetatos , Propano , Biodegradação Ambiental , Flavodoxina/metabolismo , Flavodoxina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteoma/metabolismo , Proteoma/farmacologia , Cromatografia Líquida , Burkholderia/genética , Burkholderia/metabolismo , Espectrometria de Massas em Tandem , Estresse Oxidativo , Glucose/metabolismo , Solo
10.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34341118

RESUMO

Male and female animals exhibit differences in infection outcomes. One possible source of sexually dimorphic immunity is the sex-specific costs of immune activity or pathology, but little is known about the independent effects of immune- versus microbe-induced pathology and whether these may differ for the sexes. Here, by measuring metabolic and physiological outputs in Drosophila melanogaster with wild-type and mutant immune responses, we test whether the sexes are differentially impacted by these various sources of pathology and identify a critical regulator of this difference. We find that the sexes exhibit differential immune activity but similar bacteria-derived metabolic pathology. We show that female-specific immune-inducible expression of PGRP-LB, a negative regulator of the immune deficiency (IMD) pathway, enables females to reduce immune activity in response to reductions in bacterial numbers. In the absence of PGRP-LB, females are more resistant to infection, confirming the functional importance of this regulation and suggesting that female-biased immune restriction comes at a cost.


Assuntos
Proteínas de Transporte/imunologia , Drosophila melanogaster/imunologia , Drosophila melanogaster/microbiologia , Animais , Proteínas de Transporte/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Drosophila melanogaster/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/veterinária , Feminino , Regulação da Expressão Gênica , Imunidade Inata/fisiologia , Masculino , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Proteínas Repressoras/genética , Proteínas Repressoras/imunologia , Fatores Sexuais , Transdução de Sinais/fisiologia , Triglicerídeos/metabolismo
11.
Indian J Microbiol ; 64(1): 244-253, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468734

RESUMO

Dental caries remains a prevalent concern among children globally and is associated with Candida sp. Some researchers have suggested probiotic supplements as a possible solution for reducing dental caries. A study conducted in Tamil Nadu focused on collecting 80 dental caries samples from both males and females, obtained from two different locations. The samples underwent processing using the spread plate technique, followed by anticandidal activity assessments. Through ITS sequence analysis, candida strains were identified, including C. albicans (DDGRPO1, DDGRPO2). The study specifically investigated the ability of the probiotic bacterial strain Lb. fermentum cell-free filtrate to inhibit C. albicans. The research revealed that Lb. fermentum probiotics effectively inhibited the growth of C. albicans DDGRP01, displaying strong antifungal activity against Candida sp. (98%). While these results are promising, it is worth mentioning the increasing interest in exploring innovative alternatives to probiotic-based treatments. This avenue of research offers potential for a more comprehensive approach to addressing this issue. Notably, Lb. fermentum, derived from the human oral cavity, emerges as a significant postbiotic candidate for dental prophylaxis, indicating a hopeful direction for future studies. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01175-5.

12.
J Bacteriol ; 205(1): e0037522, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36515540

RESUMO

By chance, we discovered a window of extracellular magnesium (Mg2+) availability that modulates the division frequency of Bacillus subtilis without affecting its growth rate. In this window, cells grown with excess Mg2+ produce shorter cells than do those grown in unsupplemented medium. The Mg2+-responsive adjustment in cell length occurs in both rich and minimal media as well as in domesticated and undomesticated strains. Of other divalent cations tested, manganese (Mn2+) and zinc (Zn2+) also resulted in cell shortening, but this occurred only at concentrations that affected growth. Cell length decreased proportionally with increasing Mg2+ from 0.2 mM to 4.0 mM, with little or no detectable change being observed in labile, intracellular Mg2+, based on a riboswitch reporter. Cells grown in excess Mg2+ had fewer nucleoids and possessed more FtsZ-rings per unit cell length, consistent with the increased division frequency. Remarkably, when shifting cells from unsupplemented to supplemented medium, more than half of the cell length decrease occurred in the first 10 min, consistent with rapid division onset. Relative to unsupplemented cells, cells growing at steady-state with excess Mg2+ showed an enhanced expression of a large number of SigB-regulated genes and the activation of the Fur, MntR, and Zur regulons. Thus, by manipulating the availability of one nutrient, we were able to uncouple the growth rate from the division frequency and identify transcriptional changes that suggest that cell division is accompanied by the general stress response and an enhanced demand to sequester and/or increase the uptake of iron, Mn2+, and Zn2+. IMPORTANCE The signals that cells use to trigger cell division are unknown. Although division is often considered intrinsic to the cell cycle, microorganisms can continue to grow and repeat rounds of DNA replication without dividing, indicating that cycles of division can be skipped. Here, we show that by manipulating a single nutrient, namely, Mg2+, cell division can be uncoupled from the growth rate. This finding can be applied to investigate the nature of the cell division signal(s).


Assuntos
Bacillus subtilis , Magnésio , Magnésio/metabolismo , Bacillus subtilis/metabolismo , Manganês/metabolismo , Transporte Biológico , Divisão Celular , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
13.
Neurobiol Dis ; 188: 106337, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37918758

RESUMO

Dementia with Lewy bodies and Parkinson's disease dementia are common neurodegenerative diseases that share similar neuropathological profiles and spectra of clinical symptoms but are primarily differentiated by the order in which symptoms manifest. The question of whether a distinct molecular pathological profile could distinguish these disorders is yet to be answered. However, in recent years, studies have begun to investigate genomic, epigenomic, transcriptomic and proteomic differences that may differentiate these disorders, providing novel insights in to disease etiology. In this review, we present an overview of the clinical and pathological hallmarks of Lewy body dementias before summarizing relevant research into genetic, epigenetic, transcriptional and protein signatures in these diseases, with a particular interest in those resolving "omic" level changes. We conclude by suggesting future research directions to address current gaps and questions present within the field.


Assuntos
Demência , Doença por Corpos de Lewy , Doença de Parkinson , Humanos , Doença por Corpos de Lewy/genética , Doença por Corpos de Lewy/patologia , Demência/patologia , Doença de Parkinson/patologia , Proteômica , Corpos de Lewy/patologia
14.
Small ; 19(28): e2300526, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37010008

RESUMO

Polymer-based nanocomposites are desirable materials for next-generation dielectric capacitors. 2D dielectric nanosheets have received significant attention as a filler. However, randomly spreading the 2D filler causes residual stresses and agglomerated defect sites in the polymer matrix, which leads to the growth of an electric tree, resulting in a more premature breakdown than expected. Therefore, realizing a well-aligned 2D nanosheet layer with a small amount is a key challenge; it can inhibit the growth of conduction paths without degrading the performance of the material. Here, an ultrathin Sr1.8 Bi0.2 Nb3 O10 (SBNO) nanosheet filler is added as a layer into poly(vinylidene fluoride) (PVDF) films via the Langmuir-Blodgett method. The structural properties, breakdown strength, and energy storage capacity of a PVDF and multilayer PVDF/SBNO/PVDF composites as a function of the thickness-controlled SBNO layer are examined. The seven-layered (only 14 nm) SBNO nanosheets thin film can sufficiently prevent the electrical path in the PVDF/SBNO/PVDF composite and shows a high energy density of 12.8 J cm-3 at 508 MV m-1 , which is significantly higher than that of the bare PVDF film (9.2 J cm-3 at 439 MV m-1 ). At present, this composite has the highest energy density among the polymer-based nanocomposites under the filler of thin thickness.

15.
Acta Neuropathol ; 146(1): 51-75, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37202527

RESUMO

Parkinson's Disease (PD) is a neurodegenerative and progressive disorder characterised by intracytoplasmic inclusions called Lewy bodies (LB) and degeneration of dopaminergic neurons in the substantia nigra (SN). Aggregated α-synuclein (αSYN) is known to be the main component of the LB. It has also been reported to interact with several proteins and organelles. Galectin-3 (GAL3) is known to have a detrimental function in neurodegenerative diseases. It is a galactose-binding protein without known catalytic activity and is expressed mainly by activated microglial cells in the central nervous system (CNS). GAL3 has been previously found in the outer layer of the LB in post-mortem brains. However, the role of GAL3 in PD is yet to be elucidated. In post-mortem samples, we identified an association between GAL3 and LB in all the PD subjects studied. GAL3 was linked to less αSYN in the LB outer layer and other αSYN deposits, including pale bodies. GAL3 was also associated with disrupted lysosomes. In vitro studies demonstrate that exogenous recombinant Gal3 is internalised by neuronal cell lines and primary neurons where it interacts with endogenous αSyn fibrils. In addition, aggregation experiments show that Gal3 affects spatial propagation and the stability of pre-formed αSyn fibrils resulting in short, amorphous toxic strains. To further investigate these observations in vivo, we take advantage of WT and Gal3KO mice subjected to intranigral injection of adenovirus overexpressing human αSyn as a PD model. In line with our in vitro studies, under these conditions, genetic deletion of GAL3 leads to increased intracellular αSyn accumulation within dopaminergic neurons and remarkably preserved dopaminergic integrity and motor function. Overall, our data suggest a prominent role for GAL3 in the aggregation process of αSYN and LB formation, leading to the production of short species to the detriment of larger strains which triggers neuronal degeneration in a mouse model of PD.


Assuntos
Galectina 3 , Doença de Parkinson , Animais , Humanos , Camundongos , alfa-Sinucleína/metabolismo , Neurônios Dopaminérgicos/metabolismo , Galectina 3/metabolismo , Corpos de Lewy/metabolismo , Doença de Parkinson/metabolismo
16.
Mol Ther ; 30(1): 244-255, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34687846

RESUMO

Cas12a is an RNA-guided endonuclease that has been widely used for convenient multiplex gene editing with low off-target effects. To minimize off-targeting in gene editing, we engineered a variant of LbCas12a (termed Lb-K538R) with more stringent PAM recognition, lower off-targeting capability, and similar editing efficiency in vivo compared with LbCas12a. We also demonstrated that Lb2Cas12a from Lachnospiraceae bacterium MA2020 has extensive gene-editing activities in mammalian cells. Similar to Lb-K538R, the designed Lb2Cas12a variant (termed Lb2-K518R) not only had a more stringent PAM sequence change from YYN to TYN (Y is T or C, N is A, T, C, or G), but also displayed lower off-target effects, thereby enabling more potential target site selections with low off-targeting than the common TTTV (V is A, G, or C) PAM. To determine whether this type of mutation at the homologous position had similar effects in other Cas12a, As-K548R was evaluated. Based on the results of the genome-wide off-target test, As-K548R displayed lower off-target effects. Collectively, our findings indicate that the Cas proteins could be designed to be stringent in PAM recognition to reduce their off-target effects, which suggests a promising and practical approach for minimizing off-targets effects in genome editing.


Assuntos
Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Animais , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Edição de Genes/métodos , Mamíferos , RNA/genética
17.
BMC Psychiatry ; 23(1): 823, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946220

RESUMO

BACKGROUND: This study was designed to examine the possible efficacy of the probiotic strain Lactobacillus acidophilus LB (Lacteol Fort) on attention-deficit/hyperactivity disorder (ADHD) symptomatology and evaluate its influence on cognition function. METHODS: In this randomized controlled trial, 80 children and adolescents with ADHD diagnosis, aged 6-16 years, were included. The participants were randomly assigned to two groups: one group received probiotics plus atomoxetine, whereas the other group received atomoxetine only. ADHD symptomatology was assessed using the Conners Parent Rating Scale-Revised Long Version (CPRS-R-L) and Child Behavioral Checklist (CBCL/6-18). The participants were evaluated for their vigilance and executive function using Conner's Continuous Performance Test (CPT) and Wisconsin Card Sort Test (WCST). Both groups were assessed at the beginning of the study and the end of the twelve weeks. RESULTS: The probiotic group comprised 36 patients, whereas the control group comprised 40 patients in the final analysis after four patients dropped out of the trial. After 3 months of probiotic supplementation, a significant improvement in the CPRS-R-L and CBCL total T scores was observed compared with those in the control group (p = 0.032, 0.024, respectively). Additionally, the probiotic group demonstrated improved focus attention (target accuracy rate and omission errors;p = 0.02, 0.043, respectively) compared with the control group. An analysis of the Wisconsin Card Sorting Test (WCST) performance demonstrated that the probiotic group had significantly lower perseverative (p = 0.017) and non-perseverative errors (p = 0.044) but no significant differences compared to the control group. CONCLUSION: Lactobacillus acidophilus LB supplementation combined with atomoxetine for 3 months had a beneficial impact on ADHD symptomology and a favorable influence on cognitive performance. As a result, the efficacy of probiotics as an adjunctive treatment for managing ADHD may be promising. TRIAL REGISTRATION: ClinicalTrials.gov (identifier: NCT04167995). Registration date: 19-11-2019.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Probióticos , Humanos , Criança , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Cloridrato de Atomoxetina/uso terapêutico , Lactobacillus acidophilus , Lactobacillus , Probióticos/uso terapêutico , Suplementos Nutricionais , Resultado do Tratamento
18.
J Environ Manage ; 336: 117661, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36913857

RESUMO

Extracellular polymeric substances (EPS) of activated sludge are a mixture of high molecular weight polymers secreted by microorganisms, which have the double structure of tightly-bound EPS (TB-EPS) in inner layer and loosely-bound EPS (LB-EPS) in outer layer. The characteristic of LB- and TB-EPS were different, which would affect their adsorption of antibiotics. However, the adsorption process of antibiotics on LB- and TB-EPS was still unclear yet. Therefore, in this work, the roles of LB-EPS and TB-EPS in adsorption of a typical antibiotic-trimethoprim (TMP) at environmentally relevant concentration (25.0 µg/L) were investigated. The results showed the content of TB-EPS was higher than that of LB-EPS, which was 17.08 and 10.36 mg/g VSS, respectively. The adsorption capacity of raw, LB-EPS extracted and both LB- and TB-EPS extracted activated sludges for TMP were 5.31, 4.65 and 9.51 µg/g VSS, respectively, which indicated LB-EPS had positive effect on TMP removal, while TB-EPS had negative effect. The adsorption process can be well described by a pseudo-second-order kinetic model (R2 > 0.980). The ratio of different functional groups was calculated and the CO and C-O bond might be responsible for the adsorption capacity difference between LB- and TB-EPS. The fluorescence quenching results indicated that tryptophan protein-like substances in LB-EPS provided more binding sites (n = 0.36) than that of tryptophan amino acid in TB-EPS (n = 0.1). Furthermore, the extend DLVO results also demonstrated that LB-EPS promoted the adsorption of TMP, while TB-EPS inhibited the process. We hope the results of this study were helpful for understanding the fate of antibiotics in wastewater treatment systems.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Esgotos/química , Matriz Extracelular de Substâncias Poliméricas/química , Trimetoprima/análise , Adsorção , Triptofano/análise , Antibacterianos/análise
19.
Prep Biochem Biotechnol ; 53(4): 454-463, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35848985

RESUMO

The development of new starter cultures is a crucial task for the food industry to meet technological requirements and traditional products are important reservoirs for new starter cultures. In this respect, this study aimed to isolate, identify, and determine the technological characteristics of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains originated from traditional yogurt samples. Genotypic discrimination of 200 isolates revealed the presence of distinct 19 S. thermophilus and 11 Lb. delbrueckii subsp. bulgaricus strains as potential starter cultures. Strain-specific properties determined the acidification capacity of the yogurt starter cultures and a higher acidification capacity was observed for S. thermophilus strains compared to Lb. delbrueckii subsp. bulgaricus strains. Proteolytic activity was found between 0.012-0.172 and 0.078-0.406 for S. thermophilus and Lb. delbrueckii subsp. bulgaricus strains, respectively. 4 of S. thermophilus and 3 of Lb. delbrueckii subsp. bulgaricus strains were found resistant to all tested bacteriophages. The antibiotic susceptibility tests of the isolates revealed that a very low antibiotic resistance was observed for the yogurt starter cultures. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected S. thermophilus and Lb. delbrueckii subsp. bulgaricus was calculated as 0.527 h-1 and 0.589 h-1, respectively.


Assuntos
Lactobacillus delbrueckii , Iogurte , Fermentação , Cinética , Indústria Alimentícia
20.
Saudi Pharm J ; 31(2): 228-244, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36540698

RESUMO

MERS-CoV belongs to the coronavirus group. Recent years have seen a rash of coronavirus epidemics. In June 2012, MERS-CoV was discovered in the Kingdom of Saudi Arabia, with 2,591 MERSA cases confirmed by lab tests by the end of August 2022 and 894 deaths at a case-fatality ratio (CFR) of 34.5% documented worldwide. Saudi Arabia reported the majority of these cases, with 2,184 cases and 813 deaths (CFR: 37.2%), necessitating a thorough understanding of the molecular machinery of MERS-CoV. To develop antiviral medicines, illustrative investigation of the protein in coronavirus subunits are required to increase our understanding of the subject. In this study, recombinant expression and purification of MERS-CoV (PLpro), a primary goal for the development of 22 new inhibitors, were completed using a high throughput screening methodology that employed fragment-based libraries in conjunction with structure-based virtual screening. Compounds 2, 7, and 20, showed significant biological activity. Moreover, a docking analysis revealed that the three compounds had favorable binding mood and binding free energy. Molecular dynamic simulation demonstrated the stability of compound 2 (2-((Benzimidazol-2-yl) thio)-1-arylethan-1-ones) the strongest inhibitory activity against the PLpro enzyme. In addition, disubstitutions at the meta and para locations are the only substitutions that may boost the inhibitory action against PLpro. Compound 2 was chosen as a MERS-CoV PLpro inhibitor after passing absorption, distribution, metabolism, and excretion studies; however, further investigations are required.

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