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1.
PLoS Pathog ; 19(8): e1011578, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37556475

RESUMO

Fungal insect pathogens have evolved diverse mechanisms to evade host immune recognition and defense responses. However, identification of fungal factors involved in host immune evasion during cuticular penetration and subsequent hemocoel colonization remains limited. Here, we report that the entomopathogenic fungus Beauveria bassiana expresses an endo-ß-1,3-glucanase (BbEng1) that functions in helping cells evade insect immune recognition/ responses. BbEng1 was specifically expressed during infection, in response to host cuticle and hemolymph, and in the presence of osmotic or oxidative stress. BbEng1 was localized to the fungal cell surface/ cell wall, where it acts to remodel the cell wall pathogen associated molecular patterns (PAMPs) that can trigger host defenses, thus facilitating fungal cell evasion of host immune defenses. BbEng1 was secreted where it could bind to fungal cells. Cell wall ß-1,3-glucan levels were unchanged in ΔBbEng1 cells derived from in vitro growth media, but was elevated in hyphal bodies, whereas glucan levels were reduced in most cell types derived from the BbEng1 overexpressing strain (BbEng1OE). The BbEng1OE strain proliferated more rapidly in the host hemocoel and displayed higher virulence as compared to the wild type parent. Overexpression of their respective Eng1 homologs or of BbEng1 in the insect fungal pathogens, Metarhizium robertsii and M. acridum also resulted in increased virulence. Our data support a mechanism by which BbEng1 helps the fungal pathogen to evade host immune surveillance by decreasing cell wall glucan PAMPs, promoting successful fungal mycosis.


Assuntos
Beauveria , Metarhizium , Animais , Moléculas com Motivos Associados a Patógenos/metabolismo , Glucanos/metabolismo , Beauveria/metabolismo , Sistema Imunitário/metabolismo , Parede Celular/metabolismo , Insetos/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
2.
BMC Biol ; 22(1): 81, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609978

RESUMO

BACKGROUND: Response to oxidative stress is universal in almost all organisms and the mitochondrial membrane protein, BbOhmm, negatively affects oxidative stress responses and virulence in the insect fungal pathogen, Beauveria bassiana. Nothing further, however, is known concerning how BbOhmm and this phenomenon is regulated. RESULTS: Three oxidative stress response regulating Zn2Cys6 transcription factors (BbOsrR1, 2, and 3) were identified and verified via chromatin immunoprecipitation (ChIP)-qPCR analysis as binding to the BbOhmm promoter region, with BbOsrR2 showing the strongest binding. Targeted gene knockout of BbOsrR1 or BbOsrR3 led to decreased BbOhmm expression and consequently increased tolerances to free radical generating compounds (H2O2 and menadione), whereas the ΔBbOsrR2 strain showed increased BbOhmm expression with concomitant decreased tolerances to these compounds. RNA and ChIP sequencing analysis revealed that BbOsrR1 directly regulated a wide range of antioxidation and transcription-associated genes, negatively affecting the expression of the BbClp1 cyclin and BbOsrR2. BbClp1 was shown to localize to the cell nucleus and negatively mediate oxidative stress responses. BbOsrR2 and BbOsrR3 were shown to feed into the Fus3-MAPK pathway in addition to regulating antioxidation and detoxification genes. Binding motifs for the three transcription factors were found to partially overlap in the promoter region of BbOhmm and other target genes. Whereas BbOsrR1 appeared to function independently, co-immunoprecipitation revealed complex formation between BbClp1, BbOsrR2, and BbOsrR3, with BbClp1 partially regulating BbOsrR2 phosphorylation. CONCLUSIONS: These findings reveal a regulatory network mediated by BbOsrR1 and the formation of a BbClp1-BbOsrR2-BbOsrR3 complex that orchestrates fungal oxidative stress responses.


Assuntos
Ciclinas , Fatores de Transcrição , Fatores de Transcrição/genética , Peróxido de Hidrogênio , Ciclo Celular , Estresse Oxidativo , Antioxidantes
3.
J Fish Dis ; 47(1): e13875, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37881099

RESUMO

Currently, aquaculture is a relatively mature industry; however, disease problems are continuously threatening the industry and hindering its development to a certain extent. Klebsiella pneumoniae is one of the zoonotic bacteria widely present in different hosts and has caused some degree of harm to the aquaculture industry, posing a potential threat to the water environment and indirectly also affecting human food safety issues. In this study, K. pneumoniae was isolated from the aquaculture environment, named as ELD, and subjected to pathogenic and immunological related studies. The results of the study showed that the strain carries at least four virulence-related genes, magA, wabG, ureA and uge, and has developed resistance to at least seven antibacterial drugs, such as amoxicillin, doxycycline, rifampicin, and so on. Moreover, the strain is highly pathogenic and is capable of causing systemic clinical foci in Procypris merus. In addition, after infection with K. pneumoniae, the expression of IL-1ß, IL-8, HSP70 and C2 was upregulated in P. merus as a whole, whereas the expression of TNF-α did not change significantly in any of the tissues, which might be a kind of immune response of P. merus against K. pneumoniae infection. This study provides an important theoretical basis for the in-depth exploration of the pathogenic mechanism of K. pneumoniae in fish and the immune response that occurs after the disease is contracted in fish, as well as theoretical support for the development of effective preventive and therapeutic strategies against K. pneumoniae-infected aquatic animals in the future.


Assuntos
Cyprinidae , Doenças dos Peixes , Humanos , Animais , Klebsiella pneumoniae/genética , Virulência/genética , Fatores de Virulência/genética , Antibacterianos/farmacologia , Imunidade
4.
BMC Urol ; 23(1): 17, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782230

RESUMO

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare kind of malignant soft tissue tumor with undefined differentiation, of which the incidence rate accounts for only 0.5-1.0% among all kinds of soft tissue tumors. An even rarer ASPS occurs in kidney. CASE PRESENTATION: Here we reported a case of a 7-year-old girl diagnosed with nephrogenic ASPS, regarding the analyses of the incidence, clinical manifestation, pathology and genetic diagnosis, in order to deepen the recognition of the disease. CONCLUSIONS: ASPS is very rare, and tends to occur to young patients. It is very significant to precisely diagnose ASPS at an early stage, which will be the key point for the following treatment choices and prognosis.


Assuntos
Sarcoma Alveolar de Partes Moles , Neoplasias de Tecidos Moles , Feminino , Humanos , Criança , Sarcoma Alveolar de Partes Moles/genética , Sarcoma Alveolar de Partes Moles/diagnóstico , Sarcoma Alveolar de Partes Moles/patologia , Prognóstico , Rim/patologia , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/patologia , Incidência
5.
Environ Microbiol ; 24(3): 1362-1379, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34863012

RESUMO

The insect pathogenic fungus, Metarhizium anisopliae is a commercialized microbial agent used in biological control efforts targeting a diverse range of agricultural and other insect pests. The second step in the synthesis of a group of M. anisopliae α-pyrone diterpenoids (termed subglutinols) involves the activity of a prenyltransferase family geranylgeranyl diphosphate synthase (product of the subD/MaGGPPS5 gene). Here, we show that targeted gene disruption of MaGGPPS5 results in earlier conidial germination and faster greater vegetative growth compared to the wild type (WT) parent and complemented strains. In addition, insect bioassays revealed that the ΔMaGGPPS5 mutant strain displayed significantly increased virulence, with a ~50% decrease in the mean lethal time (LT50 , from 6 to 3 days) to kill (50% of) target insects, and an ~15-40-fold decrease in the mean lethal dose (LC50 ). Metabolite profiling indicated increased accumulation in the ΔMaGGPPS5 mutant of select subglutinols (A, B and C) and destruxins (A, A2, B and B2), the latter a set of fungal secondary metabolites that act as insect toxins, with a concomitant loss of production of subglutinol 'analogue 45'. These data suggest that the increased virulence phenotype seen for the ΔMaGGPPS5 strain can, at least in part, be attributed to a combination of faster growth and increased insect toxin production, linking the production of two different secondary metabolite pathways, and represent a novel approach for the screening of isolates with enhanced virulence via modulation of terpenoid secondary metabolite biosynthesis.


Assuntos
Dimetilaliltranstransferase , Metarhizium , Animais , Dimetilaliltranstransferase/genética , Insetos/microbiologia , Mutação , Virulência/genética
6.
Fish Shellfish Immunol ; 124: 372-379, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35430348

RESUMO

Grouper iridovirus is a devastating pathogen that belongs to the genus Ranavirus. Based on the previous results that natural ingredient quercetin isolated from Illicium verum Hook. f. could effectively inhibit Singapore grouper iridovirus (SGIV) replication, suggesting that quercetin could serve as potential antiviral agent against grouper iridovirus. To know about whether quercetin has indirect antiviral activity against SGIV, this study made the investigation in vitro and in vivo, and the potential mechanism was also explored. Pretreating the cells with quercetin (12.5 µg/mL) significantly inhibited the replication of SGIV, similar results were also confirmed in vivo. Importantly, quercetin pretreatment could induce the expression of genes involved in type I interferon (IFN) system (IFN, STAT1, PKR, MxI and ISG15) and TLR9. It suggested that quercetin exerted the indirect antiviral activity against SGIV infection through promoting the recognition of SGIV and activating the IFN pathway to establish the antiviral status of host cell. Taken together, our results shedded light on the indirect antiviral function of natural ingredient quercetin, and clearly demonstrated that natural ingredient quercetin will be an excellent potential agent against SGIV infection in grouper aquaculture.


Assuntos
Bass , Infecções por Vírus de DNA , Doenças dos Peixes , Iridovirus , Plantas Medicinais , Ranavirus , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Bass/genética , Infecções por Vírus de DNA/veterinária , Quercetina/farmacologia
7.
Environ Microbiol ; 23(9): 4908-4924, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33432709

RESUMO

Genomic data have identified a class of fungal specific transcription factors (FsTFs) that are thought to regulate unique aspects of fungal gene expression, although the functions of many of these proteins remain unknown. Here, a novel FsTF (BbStf1), which features a leucine zipper dimerization domain and a fungal transcription factor regulatory middle homology region, was characterized in Beauveria bassiana, a filamentous insect fungal pathogen. Transcriptional activation and nuclear localization were experimentally confirmed for BbStf1. Disruption of Bbstf1 resulted in increased tolerance to oxidative stress and cell wall perturbation, accompanied by increased peroxidase (POD) and superoxide dismutase (SOD) activities and ratio of reduced/oxidized glutathione (GSH/GSSG), and by thickened cell wall and altered composition. Gene expression profile analysis revealed that transcription patterns of antioxidant enzyme and cell wall integrity-involved genes were altered in the ∆Bbstf1, including some BbStf1-targeted genes clarified with evidence. The ∆Bbstf1 strain displayed greater virulence to Galleria mellonella in the bioassays through both topical infection and intrahaemocoel injection due to more rapid proliferation in the haemocoel as compared to the wild-type strain. Altogether, BbStf1 acts as a negative regulator of antioxidant response, cell wall integrity and virulence in B. bassiana.


Assuntos
Beauveria , Proteínas Fúngicas , Fatores de Transcrição , Animais , Antioxidantes/metabolismo , Beauveria/genética , Beauveria/patogenicidade , Parede Celular , Proteínas Fúngicas/genética , Insetos , Esporos Fúngicos , Fatores de Transcrição/genética , Virulência
8.
Environ Microbiol ; 21(8): 3153-3171, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31211497

RESUMO

The ability to withstand heat and cell wall stress is critical for successful infection of target hosts by many pathogenic fungi. We report on the characterization of BbThm1 (transcription factor for heat and membrane integrity), a Zn(II)2 Cys6 (Gal4-like) family member, which regulates resistance to heat (32°C) and specific detergents in the insect pathogenic fungus, Beauveria bassiana. BbThm1 gene knock-out mutants showed severely impaired growth/resistance at 32°C and to SDS, but mild to moderate phenotypic responses to other stresses including oxidative, osmotic and cell-wall targeting compounds, or to various fungicides. Shifts in cell wall properties, adhesion and decreased viability were noted for the ΔBbThm1 mutant. Susceptibility to SDS but not heat could be rescued by exogenous ergosterol. Insect bioassays revealed decreased virulence of the ΔBbThm1 mutant against Galleria mellonella both topically and via intrahemocoel injection assays that correlated with impaired in insecta hyphal body formation and altered host immune prophenol oxidase (PO) activation. Transcriptomic analyses of the wild-type and ΔBbThm1 mutants revealed up-regulation of hydrolases but down-regulation of a wide range of basic metabolic processes. These data reveal fine tune aspects of the transcription factor network that regulates specific stress responses to contribute to the overall pathogenic process.


Assuntos
Beauveria/metabolismo , Beauveria/patogenicidade , Temperatura Alta , Lepidópteros/microbiologia , Fatores de Transcrição/metabolismo , Animais , Beauveria/genética , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/fisiologia , Hifas/metabolismo , Esporos Fúngicos/metabolismo , Fatores de Transcrição/genética , Virulência , Zinco/metabolismo
9.
Angew Chem Int Ed Engl ; 58(35): 12004-12009, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31265748

RESUMO

Transparent omniphobic or anti-smudge coatings with glass-like wear resistance and polymer-like bendability have many potential applications but there are no reports of such materials. We Report herein a molecular composite possessing these properties. The composite is prepared via the photo-initiated ring-opening polymerization of the epoxide rings of glycidyloxypropyl polyhedral silsesquioxane (GPOSS). While the desired hardness is provided by the silica core, the flexibility is imparted by the glycidyloxypropyl network. Oil and water repellency is achieved without adversely affecting the other properties by incorporating a low-surface-tension liquid lubricant poly(dimethyl siloxane). On the final coating, various organic solvents and water readily and cleanly glide, while complex fluids, such as ink and paint facilely contract. These properties are retained after an initially flat coating sample is rolled into a U-shape 500 times or is abraded with steel wool.

10.
Appl Microbiol Biotechnol ; 102(14): 5873-5888, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29802479

RESUMO

Significant progress has been made in the biochemical and genetic characterization of the host-pathogen interaction mediated by insect pathogenic fungi, with the most widely studied being the Ascomycetes (Hypocrealean) fungi, Metarhizium robertsii and Beauveria bassiana. However, few studies have examined the consequences and effects of host (insect) microbes, whether compatible or antagonistic, on the development and survival of entomopathogenic fungi. Host microbes can act on the insect cuticular surface, within the gut, in specialized insect microbe hosting structures, and within cells, and they include a wide array of facultative and/or obligate exosymbionts and endosymbionts. The insect microbiome differs across developmental stages and in response to nutrition (e.g., different plant hosts for herbivores) and environmental conditions, including exposure to chemical insecticides. Here, we review recent advances indicating that insect-pathogenic fungi have evolved a spectrum of strategies for exploiting or suppressing host microbes, including the production of antimicrobial compounds that are expressed at discrete stages of the infection process. Conversely, there is increasing evidence that some insects have acquired microbes that may be specialized in the production of antifungal compounds to combat infection by (entomopathogenic) fungi. Consideration of the insect microbiome in fungal insect pathology represents a new frontier that can help explain previously obscure ecological and pathological aspects of the biology of entomopathogenic fungi. Such information may lead to novel approaches to improving the efficacy of these organisms in pest control efforts.


Assuntos
Ascomicetos/fisiologia , Insetos/microbiologia , Animais , Antibiose/fisiologia , Interações Hospedeiro-Patógeno , Microbiota/fisiologia
11.
Angew Chem Int Ed Engl ; 55(47): 14610-14613, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27774756

RESUMO

A cotton fabric was coated with a polymer that contains both poly(dimethyl siloxane) (PDMS) and poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA). When the repeat unit number of PDMS is about three-fold that of PDMAEMA and the fabric is exposed to air, the fabric is superhydrophobic because PDMS in the coating covers the PDMAEMA chains. Upon contact with an oil-in-water emulsion, the water-soluble PDMAEMA rises to the top and the side in contact with the emulsion becomes hydrophilic. The emerged PDMAEMA chains then cause the emulsion droplets to coagulate, and the aggregated oil fills the pores on the superhydrophobic side of the fabric. The oil-impregnated side remains hydrophobic even upon prolonged contact with water. Thus, a Janus fabric is elegantly generated in situ and sustained. This easy-to-prepare Janus fabric rapidly and efficiently separates oil from emulsions and may find practical applications.

12.
Environ Microbiol ; 17(11): 4213-38, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25403093

RESUMO

The Hog1 mitogen-activated protein (MAP) kinase regulates environmental stress responses and virulence in the entomopathogenic fungus Beauveria bassiana. To further characterize this pathway, we constructed a subtraction library enriched for genes regulated by Hog1. One targeted gene, encoding a novel membrane protein, Ohmm (oxidative homeostasis membrane-protein-mitochondria), was uniquely identified as being downregulated in the ΔHog1 background during growth under non-stress and osmotic stress conditions, but upregulated under oxidative stress. Ohmm was an experimentally validated flavin-binding protein and targeted to the mitochondria. Deletion of Ohmm resulted in increased oxidative stress resistance, whereas overexpression caused an opposite phenotype. The ΔOhmm showed accumulation of reactive oxygen species with alterations in cell wall composition and compatible solute accumulation evident as compared with the wild type parent. Conidiation was reduced > 80%; however, conidia produced by the ΔOhmm strain germinated significantly faster than wild type cells. Insect bioassays using the greater wax moth revealed increased virulence for the ΔOhmm strain in both topical and intrahemocoel injection assays, indicating a negative effect of the presence of Ohmm with respect to pathogenesis. As predicted from our characterization, deletion of Ohmm in a ΔHog1 background rescued its oxidative sensitivity phenotype, confirming that Ohmm acts downstream of the Hog1 MAP-kinase.


Assuntos
Beauveria/patogenicidade , Proteínas de Membrana/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mariposas/microbiologia , Pressão Osmótica/fisiologia , Animais , Antioxidantes/metabolismo , Beauveria/genética , Parede Celular/metabolismo , Biblioteca Gênica , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/fisiologia , Proteínas Quinases Ativadas por Mitógeno/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Esporos Fúngicos/metabolismo , Virulência/genética
13.
Fungal Genet Biol ; 83: 78-91, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26319315

RESUMO

The entomopathogenic fungus, Beauveria bassiana, is of environmental and economic importance as an insect pathogen, currently used for the biological control of a number of pests. Cell wall integrity and conidiation are critical parameters for the ability of the fungus to infect insects and for production of the infectious propagules. The contribution of calcineurin and the Slt2 MAP kinase to cell wall integrity and development in B. bassiana was investigated. Gene knockouts of either the calcineurin CNA1 subunit or the Slt2 MAP kinase resulted in decreased tolerance to calcofluor white and high temperature. In contrast, the Δcna1 strain was more tolerant to Congo red but more sensitive to osmotic stress (NaCl, sorbitol) than the wild type, whereas the Δslt2 strain had the opposite phenotype. Changes in cell wall structure and composition were seen in the Δslt2 and Δcna1 strains during growth under cell wall stress as compared to the wild type. Both Δslt2 and Δcna1 strains showed significant alterations in growth, conidiation, and viability. Elevation of intracellular ROS levels, and decreased conidial hydrophobicity and adhesion to hydrophobic surfaces, were also seen for both mutants, as well as decreased virulence. Under cell wall stress conditions, inactivation of Slt2 significantly repressed CN-mediated phosphatase activity suggesting some level of cross talk between the two pathways. Comparative transcriptome profiling of the Δslt2 and Δcna1 strains revealed alterations in the expression of distinct gene sets, with overlap in transcripts involved in cell wall integrity, stress response, conidiation and virulence. These data illustrate convergent and divergent phenotypes and targets of the calcineurin and Slt2 pathways in B. bassiana.


Assuntos
Beauveria/enzimologia , Beauveria/patogenicidade , Calcineurina/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Beauveria/genética , Parede Celular/metabolismo , DNA Fúngico/genética , Temperatura Alta , Hifas/citologia , Hifas/crescimento & desenvolvimento , Insetos/microbiologia , Pressão Osmótica/fisiologia , Esporos Fúngicos , Estresse Fisiológico , Virulência
14.
Mol Biol Rep ; 41(7): 4253-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24584519

RESUMO

Acute respiratory distress syndrome (ARDS) is a contemporary term incorporating the historic 'acute lung injury' and the colloquial term 'shock lung'. ARDS remains a serious and enigmatic human disease, causing significant mortality. The mechanisms involved at the alveolar cell/capillary endothelial interface have been explored but to date we lack clarity on the role of intracellular calcium ([Ca(2+)]i) fluxes across this interface. To explore the mechanisms of Ca(2+) induced inflammatory reaction in epithelial cells and pulmonary microvascular endothelial cells (HMVEC) located at the two sides of blood-air barrier, lung epithelial A549 and HMVEC cells were treated with LPS. Our results demonstrated that LPS evoked the increase of [Ca(2+)]i, TNF-α and IL-8 in both cells types. The [Ca(2+)]i increases involved intracellular but not extracellular Ca(2+) sources in A549, but both intracellular and extracellular Ca(2+) sources in HMVEC cells. The effects of LPS on both cells types were completely inhibited by the combination of LPS and CaSR-targeted siRNA. Furthermore, LPS-inhibited cell proliferations were significantly reversed by the combined treatment. Therefore, LPS induced different mechanisms of [Ca(2+)]i increase during the activation of CaSR in A549 and HMVEC cells, which translates into functional outputs related to ARDS.


Assuntos
Cálcio/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Células Epiteliais/metabolismo , Lipopolissacarídeos/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Expressão Gênica , Humanos , Interleucina-8/biossíntese , Interleucina-8/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Modelos Biológicos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores de Detecção de Cálcio/antagonistas & inibidores , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismo , Síndrome do Desconforto Respiratório/genética , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/patologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo
15.
ACS Macro Lett ; 13(5): 627-631, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38708870

RESUMO

Helix-sense-selective permeation (HSSPerm) of racemic helical oligoacetylenes through one-handed helical channels has been realized. The one-handed helical channels were created in the one-handed helical polyacetylene membranes by the helix-sense-selective decomposition (HSS-SCAT) of the corresponding racemic helical polyacetylene membranes, followed by removing the formed oligomers. Since the HSS-SCAT reaction proceeds with just circularly polarized visible light with no reagents, no catalysts, no solvent, and high selectivity, the chiral channel-containing membrane with high purity was obtained easily. This membrane could separate racemic helical oligoacetylenes enantioselectively in up to 30%ee. To our knowledge, this is the first example of HSSPerm.

16.
Int J Nanomedicine ; 19: 1431-1450, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371455

RESUMO

Introduction: Basic fibroblast growth factor (bFGF) shows great potential for preventing vascular dementia (VD). However, the blood‒brain barrier (BBB) and low bioavailability of bFGF in vivo limit its application. The present study investigated how nasal administration of bFGF-loaded nanoliposomes (bFGF-lips) affects the impaired learning and cognitive function of VD mice and the underlying mechanism involved. Methods: A mouse model of VD was established through repeated cerebral ischemia‒reperfusion. A Morris water maze (MWM) and novel object recognition (NOR) tests were performed to assess the learning and cognitive function of the mice. Hematoxylin and eosin (HE) staining, Nissl staining and TUNEL staining were used to evaluate histopathological changes in mice in each group. ELISA and Western blot analysis were used to investigate the molecular mechanism by which bFGF-lips improve VD incidence. Results: Behavioral and histopathological analyses showed that cognitive function was significantly improved in the bFGF-lips group compared to the VD and bFGF groups; in addition, abnormalities and the apoptosis indices of hippocampal neurons were significantly decreased. ELISA and Western blot analysis revealed that bFGF-lips nasal administration significantly increased the concentrations of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), bFGF, B-cell lymphoma 2 (Bcl-2), phosphorylated protein kinase B (PAKT), nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H quinone oxidoreductase 1 (NQO1) and haem oxygenase-1 (HO-1) in the hippocampus of bFGF-lips mice compared with the VD and bFGF groups. Furthermore, the concentrations of malondialdehyde (MDA), caspase-3 and B-cell lymphoma 2-associated X (Bax) were clearly lower in the bFGF-lips group than in the VD and bFGF groups. Conclusion: This study confirmed that the nasal administration of bFGF-lips significantly increased bFGF concentrations in the hippocampi of VD mice. bFGF-lips treatment reduced repeated I/R-induced neuronal apoptosis by regulating apoptosis-related protein concentrations and activating the phosphatidylinositol-3-kinase (PI3K)/(AKT)/Nrf2 signaling pathway to inhibit oxidative stress.


Assuntos
Isquemia Encefálica , Demência Vascular , Camundongos , Animais , Demência Vascular/tratamento farmacológico , Demência Vascular/metabolismo , Demência Vascular/patologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Administração Intranasal , Estresse Oxidativo , Infarto Cerebral , Isquemia Encefálica/tratamento farmacológico , Cognição , Reperfusão , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose
17.
mBio ; 15(6): e0350423, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38747587

RESUMO

Successful host tissue colonization is crucial for fungal pathogens to cause mycosis and complete the infection cycle, in which fungal cells undergo a series of morphological transition-included cellular events to combat with hosts. However, many transcription factors (TFs) and their mediated networks regulating fungal pathogen colonization of host tissue are not well characterized. Here, a TF (BbHCR1)-mediated regulatory network was identified in an insect pathogenic fungus, Beauveria bassiana, that controlled insect hemocoel colonization. BbHCR1 was highly expressed in fungal cells after reaching insect hemocoel and controlled the yeast (in vivo blastospores)-to-hyphal morphological switch, evasion of immune defense response, and fungal virulence. Comparative analysis of RNA sequencing and chromatin immunoprecipitation sequencing identified a core set of BbHCR1 target genes during hemocoel colonization, in which abaA and brlA were targeted to limit the rapid switch from blastospores to hyphae and fungal virulence. Two targets encoding hypothetical proteins, HP1 and HP2, were activated and repressed by BbHCR1, respectively, which acted as a virulence factor and repressor, respectively, suggesting that BbHCR1 activated virulence factors but repressed virulence repressors during the colonization of insect hemocoel. BbHCR1 tuned the expression of two dominant hemocoel colonization-involved metabolite biosynthetic gene clusters, which linked its regulatory role in evasion of immune response. Those functions of BbHCR1 were found to be collaboratively regulated by Fus3- and Hog1-MAP kinases via phosphorylation. These findings have drawn a regulatory network in which Fus3- and Hog1-MAP kinases phosphorylate BbHCR1, which in turn controls the colonization of insect body cavities by regulating fungal morphological transition and virulence-implicated genes.IMPORTANCEFungal pathogens adopt a series of tactics for successful colonization in host tissues, which include morphological transition and the generation of toxic and immunosuppressive molecules. However, many transcription factors (TFs) and their linked pathways that regulate tissue colonization are not well characterized. Here, we identified a TF (BbHCR1)-mediated regulatory network that controls the insect fungal pathogen, Beauveria bassiana, colonization of insect hemocoel. During these processes, BbHCR1 targeted the fungal central development pathway for the control of yeast (blastospores)-to-hyphae morphological transition, activated virulence factors, repressed virulence repressors, and tuned the expression of two dominant hemocoel colonization-involved immunosuppressive and immunostimulatory metabolite biosynthetic gene clusters. The BbHCR1 regulatory function was governed by Fus3- and Hog1-MAP kinases. These findings led to a new regulatory network composed of Fus3- and Hog1-MAP kinases and BbHCR1 that control insect body cavity colonization by regulating fungal morphological transition and virulence-implicated genes.


Assuntos
Beauveria , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Fatores de Transcrição , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Beauveria/genética , Beauveria/patogenicidade , Virulência , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Insetos/microbiologia , Hifas/crescimento & desenvolvimento , Hifas/genética , Interações Hospedeiro-Patógeno
18.
J Fungi (Basel) ; 10(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38921368

RESUMO

Members of the fungal order Diaporthales are sac fungi that include plant pathogens (the notorious chestnut blight fungus), as well as saprobes and endophytes, and are capable of colonizing a wide variety of substrates in different ecosystems, habitats, and hosts worldwide. However, many Diaporthales species remain unidentified, and various inconsistencies within its taxonomic category remain to be resolved. Here, we aimed to identify and classify new species of Diaporthales by using combined morphological and molecular characterization and coupling this information to expand our current phylogenetic understanding of this order. Fungal samples were obtained from dead branches and diseasedleaves of Camellia (Theaceae) and Castanopsis (Fagaceae) in Fujian Province, China. Based on morphological characteristics and molecular phylogenetic analyses derived from the combined nucleotide sequences of loci of the internal transcribed spacer regions with the intervening 5.8S nrRNA gene (ITS), the 28S large subunit of nuclear ribosomal RNA gene (LSU), the translation elongation factor 1-α gene (tef1), the partial beta-tubulin gene (tub2), and partial RNA polymerase II second-largest subunit gene (rpb2), three new species of Diaporthales were identified and characterized. They are as follows: Chrysofolia camelliae sp. nov., Dendrostoma castanopsidis sp. nov., and Pseudoplagiostoma wuyishanense sp. nov. They are described and illustrated. This study extends our understanding of species diversity within the Diaporthales.

19.
J Fungi (Basel) ; 10(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38535196

RESUMO

The Asian water plantain, Alisma orientale (Sam.) Juzep, is a traditional Chinese medicinal plant. The dried tubers of the Alisma orientale, commonly referred to as Alismatis rhizome (AR), have long been used in traditional Chinese medicine to treat a variety of diseases. Soil properties and the soil microbial composition are known to affect the quality and bioactivity of plants. Here, we sought to identify variations in soil fungal communities and soil properties to determine which would be optimal for cultivation of A. orietale. Soil properties, heavy metal content, and pesticide residues were determined from soils derived from four different agricultural regions around Shaowu City, Fujian, China, that had previously been cultivated with various crops, namely, Shui Dao Tu (SDT, rice), Guo Shu Tu (GST, pecan), Cha Shu Tu (CST, tea trees), and Sang Shen Tu (SST, mulberry). As fungi can either positively or negatively impact plant growth, the fungal communities in the different soils were characterized using long-read PacBio sequencing. Finally, we examined the quality of A. orientale grown in the different soils. Our results show that fungal community diversity of the GST soil was the highest with saprotrophs the main functional modes in these and SDT soils. Our data show that GST and SDT soils were most suitable for A. orientale growth, with the quality of the AR tubers harvested from GST soil being the highest. These data provide a systematic approach at soil properties of agricultural lands in need of replacement and/or rotating crops. Based on our findings, GST was identified as the optimal soil for planting A. orientale, providing a new resource for local farmers.

20.
Front Microbiol ; 15: 1379879, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680916

RESUMO

Leaves of Camellia sinensis plants are used to produce tea, one of the most consumed beverages worldwide, containing a wide variety of bioactive compounds that help to promote human health. Tea cultivation is economically important, and its sustainable production can have significant consequences in providing agricultural opportunities and lowering extreme poverty. Soil parameters are well known to affect the quality of the resultant leaves and consequently, the understanding of the diversity and functions of soil microorganisms in tea gardens will provide insight to harnessing soil microbial communities to improve tea yield and quality. Current analyses indicate that tea garden soils possess a rich composition of diverse microorganisms (bacteria and fungi) of which the bacterial Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Chloroflexi and fungal Ascomycota, Basidiomycota, Glomeromycota are the prominent groups. When optimized, these microbes' function in keeping garden soil ecosystems balanced by acting on nutrient cycling processes, biofertilizers, biocontrol of pests and pathogens, and bioremediation of persistent organic chemicals. Here, we summarize research on the activities of (tea garden) soil microorganisms as biofertilizers, biological control agents and as bioremediators to improve soil health and consequently, tea yield and quality, focusing mainly on bacterial and fungal members. Recent advances in molecular techniques that characterize the diverse microorganisms in tea gardens are examined. In terms of viruses there is a paucity of information regarding any beneficial functions of soil viruses in tea gardens, although in some instances insect pathogenic viruses have been used to control tea pests. The potential of soil microorganisms is reported here, as well as recent techniques used to study microbial diversity and their genetic manipulation, aimed at improving the yield and quality of tea plants for sustainable production.

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