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1.
Bot Stud ; 65(1): 4, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252177

RESUMO

BACKGROUND: Recently, researchers are focusing on creating new tools to combat the antibiotic resistant bacteria and malignancy issues, which pose significant threats to humanity. Biosynthesized silver nanoparticles (AgNPs) are thought to be a potential solution to these issues. The biosynthesis method, known for its environmentally friendly and cost-effective characteristics, can produce small-sized AgNPs with antimicrobial and anticancer properties. In this study, AgNPs were bio-fabricated from the distilled water and methanolic extracts of Viburnum grandiflorum leaves. Physio-chemical characterization of the bio-fabricated AgNPs was conducted using UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis. RESULTS: AgNPs produced from the methanol extract were smaller in size (12.28 nm) compared to those from the aqueous extract (17.77 nm). The bioengineered AgNPs exhibited a circular shape with a crystalline nature. These biosynthesized AgNPs demonstrated excellent bactericidal activity against both gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. Highest antibacterial activity was observed with the methanol extract against P. aeruginosa (14.66 ± 0.74 mm). AgNPs from the methanol extract also displayed the highest antioxidant activity, with an IC50 value of 188.00 ± 2.67 µg/mL against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, AgNPs exhibited notable cytotoxic activity against Rhabdomyosarcoma cell line (RD cell) of human muscle cancer cell. The IC50 values calculated from the MTT assay were 26.28 ± 1.58 and 21.49 ± 1.44 µg/mL for AgNPs synthesized from aqueous and methanol extracts, respectively. CONCLUSION: The methanol extract of V. grandiflorum leaves demonstrates significant potential for synthesizing AgNPs with effective antibacterial, antioxidant, and anticancer actions, making them applicable in various biomedical applications.

2.
Front Immunol ; 14: 1219072, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483638

RESUMO

Innate lymphoid cells (ILCs) are key regulators of tissue homeostasis, inflammation, and immunity to infections. ILCs rapidly respond to environmental cues such as cytokines, microbiota and invading pathogens which regulate their function and phenotype. Even though ILCs are rare cells, they are enriched at barrier surfaces such as the gastrointestinal (GI) tract, and they are often critical to the host's immune response to eliminate pathogens. On the other side of host-pathogen interactions, pathogenic bacteria also have the means to modulate these immune responses. Manipulation or evasion of the immune cells is often to the pathogen's benefit and/or to the detriment of competing microbiota. In some instances, specific bacterial virulence factors or toxins have been implicated in how the pathogen modulates immunity. In this review, we discuss the recent progress made towards understanding the role of non-cytotoxic ILCs during enteric bacterial infections, how these pathogens can modulate the immune response, and the implications these have on developing new therapies to combat infection.


Assuntos
Microbioma Gastrointestinal , Imunidade Inata , Humanos , Linfócitos , Inflamação , Trato Gastrointestinal , Enterobacteriaceae , Bactérias
3.
Front Plant Sci ; 13: 964092, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247644

RESUMO

Pectobacterium brasiliense (P. brasiliense) is a necrotrophic bacterium that causes the soft rot disease in Brassica rapa. However, the mechanisms underlying plant immune responses against necrotrophic bacterial pathogens with a broad host range are still not well understood. Using a flg22-triggered seedling growth inhibition (SGI) assay with 455 Brassica rapa inbred lines, we selected six B. rapa flagellin-insensitive lines (Brfin2-7) and three B. rapa flagellin-sensitive lines (Brfs1-3). Brfin lines showed compromised flg22-induced immune responses (oxidative burst, mitogen-activated protein kinase (MAPK) activation, and seedling growth inhibition) compared to the control line R-o-18; nevertheless, they were resistant to P. brasiliense. To explain this, we analyzed the phytohormone content and found that most Brfin lines had higher P. brasiliense-induced jasmonic acid (JA) than Brfs lines. Moreover, MeJA pretreatment enhanced the resistance of B. rapa to P. brasiliense. To explain the correlation between the resistance of Brfin lines to P. brasiliense and activated JA signaling, we analyzed pathogen-induced glucosinolate (GS) content in B. rapa. Notably, in Brfin7, the neoglucobrassicin (NGBS) content among indole glucosinolates (IGS) was significantly higher than that in Brfs2 following P. brasiliense inoculation, and genes involved in IGSs biosynthesis were also highly expressed. Furthermore, almost all Brfin lines with high JA levels and resistance to P. brasiliense had higher P. brasiliense-induced NGBS levels than Brfs lines. Thus, our results show that activated JA-mediated signaling attenuates flg22-triggered immunity but enhances resistance to P. brasiliense by inducing indole glucosinolate biosynthesis in Brassica rapa. This study provides novel insights into the role of JA-mediated defense against necrotrophic bacterial pathogens within a broad host range.

4.
Int J Mol Sci ; 23(13)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-35806412

RESUMO

The abuse or misuse of antibiotics has caused the emergence of extensively drug-resistant (XDR) bacteria, rendering most antibiotics ineffective and increasing the mortality rate of patients with bacteremia or sepsis. Antimicrobial peptides (AMPs) are proposed to overcome this problem; however, many AMPs have attenuated antimicrobial activities with hemolytic toxicity in blood. Recently, AMPR-11 and its optimized derivative, AMPR-22, were reported to be potential candidates for the treatment of sepsis with a broad spectrum of antimicrobial activity and low hemolytic toxicity. Here, we performed molecular dynamics (MD) simulations to clarify the mechanism of lower hemolytic toxicity and higher efficacy of AMPR-22 at an atomic level. We found four polar residues in AMPR-11 bound to a model mimicking the bacterial inner/outer membranes preferentially over eukaryotic plasma membrane. AMPR-22 whose polar residues were replaced by lysine showed a 2-fold enhanced binding affinity to the bacterial membrane by interacting with bacterial specific lipids (lipid A or cardiolipin) via hydrogen bonds. The MD simulations were confirmed experimentally in models that partially mimic bacteremia conditions in vitro and ex vivo. The present study demonstrates why AMPR-22 showed low hemolytic toxicity and this approach using an MD simulation would be helpful in the development of AMPs.


Assuntos
Bacteriemia , Proteínas de Membrana , Proteínas Mitocondriais , Simulação de Dinâmica Molecular , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Bacteriemia/metabolismo , Bactérias , Membrana Celular/metabolismo , Hemólise , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/farmacologia , Testes de Sensibilidade Microbiana , Proteínas Mitocondriais/química , Proteínas Mitocondriais/farmacologia
5.
Food Chem X ; 14: 100302, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35434600

RESUMO

Kombucha, originated in China 2000  years ago, is a sour and sweet-tasted drink, prepared traditionally through fermentation of black tea. During the fermentation of kombucha, consisting of mainly acidic compounds, microorganisms, and a tiny amount of alcohol, a biofilm called SCOBY forms. The bacteria in kombucha has been generally identified as Acetobacteraceae. Kombucha is a noteworthy source of B complex vitamins, polyphenols, and organic acids (mainly acetic acid). Nowadays, kombucha is tended to be prepared with some other plant species, which, therefore, lead to variations in its composition. Pre-clinical studies conducted on kombucha revealed that it has desired bioactivities such as antimicrobial, antioxidant, hepatoprotective, anti-hypercholestorelomic, anticancer, anti-inflammatory, etc. Only a few clinical studies have been also reported. In the current review, we aimed to overhaul pre-clinical bioactivities reported on kombucha as well as its brief compositional chemistry. The literature data indicate that kombucha has valuable biological effects on human health.

6.
Front Immunol ; 12: 671331, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566952

RESUMO

The intestinal microbiota modulates IL-22 production in the intestine, including the induction of IL-22-producing CD4+ T helper cells. Which specific bacteria are responsible for the induction of these cells is less well understood. Here, we demonstrate through the use of novel gnotobiotic knock-in reporter mice that segmented filamentous bacteria (SFB), which are known for their ability to induce Th17 cells, also induce distinct IL-17A negative CD4+ T cell populations in the intestine. A subset of these cells instead produces IL-22 upon restimulation ex vivo and also during enteric infections. Furthermore, they produce a distinct set of cytokines compared to Th17 cells including the differential expression of IL-17F and IFN-γ. Importantly, genetic models demonstrate that these cells, presumably Th22 cells, develop independently of intestinal Th17 cells. Together, our data identifies that besides Th17, SFB also induces CD4+ T cell populations, which serve as immediate source of IL-22 during intestinal inflammation.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Microbioma Gastrointestinal/imunologia , Interleucinas/imunologia , Células Th17/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Interleucinas/biossíntese , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Salmonella typhi , Células Th17/metabolismo , Febre Tifoide/imunologia , Febre Tifoide/microbiologia
7.
World J Microbiol Biotechnol ; 37(6): 103, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34013421

RESUMO

Microbiocides are used to control problematic microorganisms. High doses of microbiocides cause environmental and operational problems. Therefore, using microbiocide enhancers to make microbiocides more efficacious is highly desirable. 2,2-dibromo-3-nitrilopropionamide (DBNPA) is a popular biodegradable microbiocide. D-Amino acids have been used in lab tests to enhance microbiocides to treat microbial biofilms. In this investigation, D-tyrosine was used to enhance DBNPA against Desulfovibrio vulgaris biofilm on C1018 carbon steel. After 7 days of incubation, the mass loss of coupons without treatment chemicals in the ATCC 1249 culture medium was found to be 3.1 ± 0.1 mg/cm2. With 150 ppm (w/w) DBNPA in the culture medium, the mass loss was reduced to 1.9 ± 0.1 mg/cm2 accompanied by a 1-log reduction in the sessile cell count. The 150 ppm DBNPA + 1 ppm D-tyrosine combination attained an extra 3-log reduction in sessile cell count and an additional 30% reduction in mass loss compared with 150 ppm DBNPA only treatment. The combination also led to a smaller maximum pit depth. Linear polarization resistance (LPR), electrochemical impedance spectrometry (EIS), and potentiodynamic polarization (PDP) tests corroborated the enhancement effects.


Assuntos
Biofilmes/efeitos dos fármacos , Carbono/química , Desulfovibrio vulgaris/fisiologia , Nitrilas/farmacologia , Tirosina/química , Corrosão , Meios de Cultura/química , Desulfovibrio vulgaris/efeitos dos fármacos , Espectroscopia Dielétrica , Testes de Sensibilidade Microbiana , Nitrilas/química , Oxirredução , Aço/química , Sulfatos/metabolismo
8.
World J Gastroenterol ; 26(21): 2702-2714, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32550748

RESUMO

Inflammatory bowel disease (IBD) is an inflammatory disorder of the gastrointestinal tract that affects millions of patients worldwide. It has a complex and multifactorial etiology leading to excessive exposure of intestinal epithelium to microbial antigens, inappropriate activation of the immune system and ultimately to the damage of intestinal tissues. Although numerous efforts have been made to improve the disease management, IBD remains persistently recurring and beyond cure. This is due largely to the gaps in our understanding of the pathogenesis of IBD that hamper the development of timely diagnoses and effective treatment. However, some recent discoveries, including the beneficial effects of interleukin-22 (IL-22) on the inflamed intestine, have shed light on a self-protective mechanism in IBD. Regenerating islet-derived (REG/Reg) proteins are small secretory proteins which function as IL-22's downstream effectors. Mounting studies have demonstrated that IBD patients have significantly increased REG expressions in the injured intestine, but with undefined mechanisms and roles. The reported functions of REG/Reg proteins in intestinal homeostasis, such as those of antibacterial, anti-inflammatory and tissue repair, lead us to discuss their potential mechanisms and clinical relevance in IBD in order to advance IBD research and management.


Assuntos
Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Células Enteroendócrinas/metabolismo , Interleucinas/metabolismo , Proteínas Associadas a Pancreatite/metabolismo , Colite Ulcerativa/patologia , Colo/imunologia , Colo/patologia , Doença de Crohn/patologia , Células Enteroendócrinas/imunologia , Humanos , Interleucinas/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Proteínas Associadas a Pancreatite/imunologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-32010538

RESUMO

Recently, we found a novel function of the lactic acid bacterium Tetragenococcus halophilus derived from miso, a fermented soy paste, that induces interleukin (IL)-22 production in B cells preferentially. IL-22 plays a critical role in barrier functions in the gut and skin. We further screened other bacteria species, namely, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Weissella, Pediococcus, and Bacillus, in addition to Tetragenococcus and found that some of them possessed robust IL-22-inducible function in B cells in vitro. This process resulted in the augmented expression of activation markers CD86 and CD69 on B and T cells, respectively. However, these observations were not correlated with IL-22 production. We isolated Bacillus coagulans sc-09 from miso and determined it to be the best strain to induce robust IL-22 production in B cells. Furthermore, feeding B. coagulans sc-09 to mice augmented the barrier function of the skin regardless of gut microbiota.

10.
Nutrients ; 11(12)2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31817820

RESUMO

Accumulating evidence clarifies that intestinal barrier function, for example, by the mucus layer, antimicrobial peptides, immune systems, and epithelial tight junctions, plays crucial roles in maintaining our health. We reported previously that yogurt fermented with Lactobacillus delbrueckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131 induced the gene expression of the regenerating family member 3 (REG3) family, which encodes antimicrobial peptides in the small intestine, although it was unclear how the yogurt activated the intestinal cells related to it. Here, we evaluated the cytokine production from the intestinal immune cells stimulated by these strains in vitro and in vivo to elucidate the mechanism for the induction of the REG3 family by the yogurt. The results showed that stimulation by both strains induced interleukin (IL)-23 production from bone marrow-derived dendritic cells (DCs) and IL-22 production from small intestinal lamina propria (LP) cells. In addition, oral administration of these strains to mice increased IL-23p19+ LPDCs and IL-22+ type 3 innate lymphoid cells and induced the expression of Reg3g in small intestinal tissue. Moreover, we showed that the activities for the induction of IL-23 by DCs were strain dependent on L. bulgaricus and S. thermophilus and that S. thermophilus 1131, which is the predominant species in the yogurt, exhibited relatively higher activity compared to the other strains of S. thermophilus. Our findings suggested that these yogurt starter strains, L. bulgaricus 2038 and S. thermophilus 1131, have the potential to maintain and improve intestinal barrier function by stimulating immune cells in the LP.


Assuntos
Células Dendríticas/microbiologia , Interleucina-23/metabolismo , Interleucinas/metabolismo , Intestino Delgado/microbiologia , Lactobacillus delbrueckii/fisiologia , Linfócitos/microbiologia , Streptococcus thermophilus/fisiologia , Administração Oral , Animais , Fermentação , Expressão Gênica , Interleucina-23/genética , Interleucinas/genética , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mucosa/microbiologia , Proteínas Associadas a Pancreatite/genética , Iogurte/microbiologia
11.
Acta Biomater ; 81: 158-168, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30268915

RESUMO

An esterase from S. mutans UA159, SMU_118c, was shown to hydrolyze methacrylate resin-based dental monomers. OBJECTIVE: To investigate the association of SMU_118c to the whole cellular hydrolytic activity of S. mutans toward polymerized resin composites, and to examine how the bacterium adapts its hydrolytic activity in response to environmental stresses triggered by the presence of a resin composites and adhesives biodegradation by-product (BBP). MATERIALS AND METHODS: Biofilms of S. mutans UA159 parent wild strain, SMU_118c knockout strain (ΔSMU_118c), and SMU_118c complemented strain (ΔSMU_118cC) were incubated with photo-polymerized resin composite. High performance liquid chromatography was used to quantify the amount of a universal 2,2-Bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (bisGMA)-derived BBP, bishydroxy-propoxy-phenyl-propane (bisHPPP) in the media. Fluorescence in situ hybridization (FISH) and quantitative proteomic analysis were used to measure SMU_118c gene expression and production of SMU_118c protein, respectively, from biofilms of S. mutans UA159 wild strain that were cultured with bisHPPP. RESULTS: The levels of bisHPPP released from composite were similar for ΔSMU_118c and media control, and these were significantly lower compared to the parent wild-strain UA159 and complemented strain (ΔSMU_118cC) (p < 0.05). Gene expression of SMU_118c and productions of SMU_118c protein were higher for bisHPPP incubated biofilms (p < 0.05). SIGNIFICANCE: This study suggests that SMU_118c is a dominant esterase in S. mutans and capable of catalyzing the hydrolysis of the resinous matrix of polymerized composites and adhesives. In turn, the bacterial response to BBP was to increase the expression of the esterase gene and enhance esterase production, potentially accelerating the biodegradation of the restoration, adhesive and restoration-tooth interface, ultimately contributing to premature restoration failure. STATEMENT OF SIGNIFICANCE: We recently reported (Huang et al., 2018) on the isolation and initial characterization of a specific esterase (SMU_118c) from S. mutans that show degradative activity toward the hydrolysis of dental monomers. The current study further characterize this enzyme and shows that SMU_118c is a dominant degradative esterase activity in the cariogenic bacterium S. mutans and is capable of catalyzing the hydrolysis of the resinous matrix of polymerized composites and adhesives. In turn, the bacterial response to biodegradation by-products from composites and adhesives was to increase the expression of the esterase gene and enhance esterase production, accelerating the biodegradation of the restoration, adhesive and the restoration-tooth interface, potentially contributing to the pathogenesis of recurrent caries around resin composite restorations.


Assuntos
Adesivos/farmacologia , Proteínas de Bactérias/biossíntese , Resinas Compostas/farmacologia , Esterases/biossíntese , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Metacrilatos/farmacologia , Streptococcus mutans/enzimologia
12.
Food Chem ; 253: 247-254, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29502828

RESUMO

Ketocarotenoids are high-value natural pigments. The red diketocarotenoid astaxanthin particularly exhibits an extraordinary antioxidant activity, which raises its market demand for foods and nutraceuticals. We screened for ketocarotenoid-producing bacteria from both marine and freshwater environments. Phylogenetic analysis, based on 16S rRNA gene sequence, revealed 37 potential producers of ketocarotenoids that are related to α-proteobacteria, comprising 32 strains of Brevundimonas and 5 strains of Erythrobacter. Carotenoids analysis by HPLC-DAD and HPLC-MS revealed two groups; astaxanthin-producers (28 Brevundimonas strains) and adonixanthin-producers (Five Brevundimonas and 5 Erythrobacter strains). Strain FrW-Asx16 exhibited the highest carotenoid production (1060 µg g-1 dry cells with 16.6% astaxanthin). Strain FrW-Asx-5 producing 946.1 µg g-1 dry cells carotenoid exhibited the highest astaxanthin content (∼46%). The most intriguing result is the potential of producing natural colorants from freshwater bacterial isolates, and with high productivity and selectivity, suggesting a great promise for their application in food.


Assuntos
Organismos Aquáticos/química , Bactérias/química , Carotenoides/análise , Carotenoides/química , Meio Ambiente , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Bactérias/classificação , Bactérias/genética , Carotenoides/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética
13.
Food Chem ; 250: 148-154, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29412905

RESUMO

This study was conducted to investigate the effect of lactic acid bacteria (LAB) strains on color properties, phenolic profile and antioxidant activities of mulberry juice. Mulberry juice was separately fermented at 37 °C for 36 h using Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus paracasei. The results showed that lactic acid fermentation impacted on the color of the juice. Moreover, the study demonstrated that LABs impacted on the phenolic profile of the juice. Syringic acid, cyanidin-3-O-rutinoside and quercetin were the predominant phenolic acid, anthocyanin and flavonol respectively in the lactic-acid-fermented mulberry juice. The degree of radical scavenging activity was species-specific with the L. plantarum fermented juice having the highest radical scavenging activities. The correlation analysis demonstrated that flavonols and anthocyanins were mostly responsible for the increased in 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity while phenolic acids and flavonols were responsible for 2,2-diphenyl-1-picrylhydrazyl scavenging activity and reducing power capacity of the fermented juice.


Assuntos
Fermentação , Sucos de Frutas e Vegetais/microbiologia , Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Morus/metabolismo , Morus/microbiologia , Fenóis/análise , Antioxidantes/análise , Antioxidantes/química , Cor , Morus/química , Fenóis/química
14.
Int J Chron Obstruct Pulmon Dis ; 12: 1857-1865, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694696

RESUMO

COPD is characterized by an ongoing inflammatory process of the airways that leads to obstruction or limitation of airflow. It is mainly associated with exposure to cigarette smoke. In addition, it is considered, at present, a serious public health problem, ranking fourth in mortality worldwide. Many cells participate in the pathophysiology of COPD, the most important are neutrophils, macrophages and CD4+ and CD8+ T cells. Neutrophil migration to the inflammation area could be mediated largely by cytokines related to CD4+ Th17 lymphocytes, because it has been shown that IL-17A, IL-17F and IL-22 act as inducers for CXCL8, CXCL1, CXCL5, G-CSF, and GM-CSF secretion by epithelial cells of the airways. The aims of these molecules are differentiation, proliferation and recruitment of neutrophils. Furthermore, it is believed that CD4+ lymphocytes Th17 may be involved in protection against pathogens for which Th1 and Th2 are not prepared to fight. In COPD exacerbations, there is an increased cellularity in the lung region and respiratory tract. Therefore, the increase in the number of neutrophils and macrophages in the airways and the increase in proinflammatory cytokines are directly related to the severity of exacerbations and that is the importance of the functions of Th17 profile in this entity.


Assuntos
Citocinas/imunologia , Pulmão/imunologia , Ativação Linfocitária , Doença Pulmonar Obstrutiva Crônica/imunologia , Células Th17/imunologia , Imunidade Adaptativa , Animais , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/imunologia , Quimiotaxia , Fumar Cigarros/efeitos adversos , Fumar Cigarros/epidemiologia , Fumar Cigarros/imunologia , Citocinas/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Humanos , Imunidade Inata , Pulmão/metabolismo , Pulmão/fisiopatologia , Macrófagos/imunologia , Macrófagos/metabolismo , Infiltração de Neutrófilos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fenótipo , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/imunologia , Fatores de Risco , Transdução de Sinais , Células Th17/metabolismo , Viroses/epidemiologia , Viroses/imunologia
15.
J Hazard Mater ; 329: 38-48, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28122276

RESUMO

Triclocarban (TCC) is an emerging and persistent pollutant once released into environment. In this study, TCC-degrading Ochrobactrum sp. MC22, was isolated and characterized. This is the first report on plant-growth promoting bacterium with versatile capability of TCC degradation under aerobic and anaerobic conditions. The aerobic degradation of TCC occurred completely of which the kinetic analysis revealed a non-self-inhibitive substrate effect, and broad-concentration-range degradation efficiency (ranging from 0.16-30mgL-1). Anaerobic TCC degradation was feasible, but was significantly enhanced up to 40-50% when ferric, or acetate was provided as electron donor, or acceptor, respectively. TCC biodegradation under both conditions was proposed to initially occur through hydrolysis leading to transient accumulation of chloroanilines, which could be completely metabolized and detoxified. With concern on TCC adverse effect to plants, role of MC22 on toxicity mitigation was investigated using two legume plants: Vigna radiata and Glycine max (L.) Merr. Upon TCC exposure, damage of both plant structures, especially root system was observed, but was substantially mitigated by MC22 bioaugmentation. This study not only provides thorough TCC degradation characteristic and kinetics of MC22, but also suggests a potential role of this bacterial strain for a rhizoremediation in crop area with TCC contamination.


Assuntos
Carbanilidas/metabolismo , Ochrobactrum/isolamento & purificação , Poluentes do Solo/metabolismo , Vigna/efeitos dos fármacos , Aerobiose , Anaerobiose , Biodegradação Ambiental , Carbanilidas/toxicidade , Testes de Mutagenicidade , Ochrobactrum/metabolismo , Cebolas , Desenvolvimento Vegetal , Poluentes do Solo/toxicidade
16.
Immunol Lett ; 165(1): 1-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25794634

RESUMO

Anatomical containment of commensal bacteria in the intestinal mucosa is promoted by innate lymphoid cells (ILCs). However, the mechanism by which ILCs regulate bacterial localization to specific regions remains unknown. Here we show that Peyer's patch (PP) ILCs robustly produce IL-22 and IFN-γ in the absence of exogenous stimuli. Antibiotic treatment of mice decreased both IL-22+ and IFN-γ+ cells in PPs. Blockade of both IL-2 and IL-23 signaling in vitro lowered IL-22 and IFN-γ production. PP ILCs induced mRNA expression of the antibacterial proteins RegIIIß and RegIIIγ in intestinal epithelial cells. Furthermore, in vivo depletion of ILCs rather than T cells altered bacterial composition and allowed bacterial proliferation in PPs. Collectively, our results show that ILCs regulate the expansion of commensal bacteria in PPs.


Assuntos
Fenômenos Fisiológicos Bacterianos/imunologia , Imunidade Inata/fisiologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Subpopulações de Linfócitos/imunologia , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/imunologia , Animais , Antígenos de Superfície/metabolismo , Bactérias , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Citocinas/biossíntese , Microbioma Gastrointestinal/imunologia , Imunofenotipagem , Interferon gama/biossíntese , Interleucinas/biossíntese , Mucosa Intestinal/metabolismo , Subpopulações de Linfócitos/metabolismo , Camundongos , Proteínas Associadas a Pancreatite , Proteínas/metabolismo , Transdução de Sinais
17.
J Exp Bot ; 65(22): 6487-98, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25205577

RESUMO

Pathogens can colonize all plant organs and tissues. To prevent this, each cell must be capable of autonomously triggering defence. Therefore, it is generally assumed that primary sensors of the immune system are constitutively present. One major primary sensor against bacterial infection is the flagellin sensing 2 (FLS2) pattern recognition receptor (PRR). To gain insights into its expression pattern, the FLS2 promoter activity in ß-glucuronidase (GUS) reporter lines was monitored. The data show that pFLS2::GUS activity is highest in cells and tissues vulnerable to bacterial entry and colonization, such as stomata, hydathodes, and lateral roots. GUS activity is also high in the vasculature and, by monitoring Ca(2+) responses in the vasculature, it was found that this tissue contributes to flg22-induced Ca(2+) burst. The FLS2 promoter is also regulated in a tissue- and cell type-specific manner and is responsive to hormones, damage, and biotic stresses. This results in stimulus-dependent expansion of the FLS2 expression domain. In summary, a tissue- and cell type-specific map of FLS2 expression has been created correlating with prominent entry sites and target tissues of plant bacterial pathogens.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Bactérias/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Brotos de Planta/genética , Brotos de Planta/microbiologia , Proteínas Quinases/metabolismo , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Flagelina/metabolismo , Ácidos Indolacéticos/metabolismo , Modelos Biológicos , Especificidade de Órgãos/genética , Raízes de Plantas/crescimento & desenvolvimento , Estômatos de Plantas/fisiologia , Proteínas Quinases/genética , Estresse Fisiológico/genética
18.
MethodsX ; 1: 254-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26150961

RESUMO

Lactic acid is a valuable and fully degradable organic acid with promising applications in poly-lactic acid production (Taskila S and Ojamo, 2013 [1]). Despite their efficiency, the cost of the current lactic acid bio-processes is still an obstacle to this application (Miller et al., 2011 [2]). To ameliorate lactic acid producing strains, researchers are using mutations and metabolic engineering techniques, as well as medium optimization. All these studies necessitate a good and high throughput screening method. Currently, researchers mostly use HPLC methods which often necessitate sample preparation, are not stereospecific and do not allow high throughput. To help optimizing l-lactic acid production, we developed a high throughput colorimetric method inspired by the blood l-lactic acid detection method used for diagnosis (Lin et al., 1999 [3]).•Two sequential enzymatic reactions using l-lactate oxidase, peroxidase and ABTS (2,2'-azino-di-[3-ethylbenzthiazoine-sulfonate]), a chromogenic peroxidase substrate, are used to quantify l-lactate between 13.8 and 90 mg/l.•The accuracy of the method was ascertained before automation.•The method was successfully applied for the direct determination of l-lactate content in fungal culture supernatants.

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