Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Braz. j. biol ; 84: e254552, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360202

RESUMO

Anti-tuberculosis drugs are reported to cause hepatotoxicity, which varies from asymptomatic rise of the hepatic enzymes. Hepatoprotective plants plays important role to protect liver. This study investigated the hepatoprotective potential of the Solanum lycopersicum in rats intoxicated with Isoniazid and Rifampicin (INH+RIF) to induce hepatotoxicity. Thirty wistar albino rats were divided into five groups of six animals each. Group 1 rats were kept control while groups II, III, IV and V were administered with INH+RIF (75+150 mg/kg) orally, for seven consecutive days. For treatment, rats in group III received silymarin while animals in group IV and V were provided with 40 mg/kg and 80 mg/kg of Solanum lycopersicum extract, respectively. On day 0 and 8th blood samples were collected for the analysis of hepatic biomarkers. The data were subjected to one-way ANOVA and Bonferroni's post hoc test for statistical analysis. Hepatotoxicity induced by INH+RIF resulted in significant elevation of serum hepatic enzymes including Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP), and total bilirubin while decreased the albumin level. The Solanum lycopersicum at dose of 80 mg/kg significantly reduced the hepatic enzymes AST, ALT, ALP and bilirubin while the albumin level was significantly increased. The treatment had non-significant effect on body and liver weight. Drug induced hepatotoxicity can be effectively treated with Solanum lycopersicum at 80 mg/kg dose.


As drogas antituberculose são relatadas como causadoras de hepatotoxicidade, ocasionando o aumento assintomático das enzimas hepáticas. As plantas hepatoprotetoras desempenham um papel importante na proteção do fígado. Este estudo investigou o potencial hepatoprotetor de Solanum lycopersicum em ratos que foram intoxicados com isoniazida e rifampicina (INH + RIF) para induzir hepatotoxicidade. Trinta ratos wistar albinos foram divididos em cinco grupos de seis animais cada. Os ratos do grupo 1 representaram o grupo controle, enquanto os ratos dos grupos II, III, IV e V receberam INH + RIF (75 + 150 mg/kg) por via oral, por sete dias consecutivos. Para o tratamento, os ratos do grupo III receberam silimarina, enquanto os animais do grupo IV e V receberam 40 mg/kg e 80 mg/kg de extrato de S. lycopersicum, respectivamente. Nos dias 0 e 8, foram coletadas amostras de sangue para análise de biomarcadores hepáticos. Os dados foram submetidos a teste unilateral (ANOVA) e post hoc de Bonferroni para análise estatística. A hepatotoxicidade induzida por INH + RIF resultou em elevação significativa das enzimas hepáticas séricas, incluindo aspartato aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina (ALP) e bilirrubina total, enquanto houve a diminuição do nível de albumina. O S. lycopersicum, na dose de 80 mg / kg, reduziu significativamente as enzimas hepáticas AST, ALT, ALP e bilirrubina, enquanto o nível de albumina aumentou de forma significativa. O tratamento não teve efeito significativo no peso corporal e hepático. A hepatotoxicidade induzida por drogas pode ser tratada de forma eficaz com S. lycopersicum na dose de 80 mg/kg.


Assuntos
Animais , Ratos , Ratos Wistar , Solanum lycopersicum , Fígado/efeitos dos fármacos , Antituberculosos
2.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469343

RESUMO

Abstract Anti-tuberculosis drugs are reported to cause hepatotoxicity, which varies from asymptomatic rise of the hepatic enzymes. Hepatoprotective plants plays important role to protect liver. This study investigated the hepatoprotective potential of the Solanum lycopersicum in rats intoxicated with Isoniazid and Rifampicin (INH+RIF) to induce hepatotoxicity. Thirty wistar albino rats were divided into five groups of six animals each. Group 1 rats were kept control while groups II, III, IV and V were administered with INH+RIF (75+150 mg/kg) orally, for seven consecutive days. For treatment, rats in group III received silymarin while animals in group IV and V were provided with 40 mg/kg and 80 mg/kg of Solanum lycopersicum extract, respectively. On day 0 and 8th blood samples were collected for the analysis of hepatic biomarkers. The data were subjected to one-way ANOVA and Bonferronis post hoc test for statistical analysis. Hepatotoxicity induced by INH+RIF resulted in significant elevation of serum hepatic enzymes including Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP), and total bilirubin while decreased the albumin level. The Solanum lycopersicum at dose of 80 mg/kg significantly reduced the hepatic enzymes AST, ALT, ALP and bilirubin while the albumin level was significantly increased. The treatment had non-significant effect on body and liver weight. Drug induced hepatotoxicity can be effectively treated with Solanum lycopersicum at 80 mg/kg dose.


Resumo As drogas antituberculose são relatadas como causadoras de hepatotoxicidade, ocasionando o aumento assintomático das enzimas hepáticas. As plantas hepatoprotetoras desempenham um papel importante na proteção do fígado. Este estudo investigou o potencial hepatoprotetor de Solanum lycopersicum em ratos que foram intoxicados com isoniazida e rifampicina (INH + RIF) para induzir hepatotoxicidade. Trinta ratos wistar albinos foram divididos em cinco grupos de seis animais cada. Os ratos do grupo 1 representaram o grupo controle, enquanto os ratos dos grupos II, III, IV e V receberam INH + RIF (75 + 150 mg/kg) por via oral, por sete dias consecutivos. Para o tratamento, os ratos do grupo III receberam silimarina, enquanto os animais do grupo IV e V receberam 40 mg/kg e 80 mg/kg de extrato de S. lycopersicum, respectivamente. Nos dias 0 e 8, foram coletadas amostras de sangue para análise de biomarcadores hepáticos. Os dados foram submetidos a teste unilateral (ANOVA) e post hoc de Bonferroni para análise estatística. A hepatotoxicidade induzida por INH + RIF resultou em elevação significativa das enzimas hepáticas séricas, incluindo aspartato aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina (ALP) e bilirrubina total, enquanto houve a diminuição do nível de albumina. O S. lycopersicum, na dose de 80 mg / kg, reduziu significativamente as enzimas hepáticas AST, ALT, ALP e bilirrubina, enquanto o nível de albumina aumentou de forma significativa. O tratamento não teve efeito significativo no peso corporal e hepático. A hepatotoxicidade induzida por drogas pode ser tratada de forma eficaz com S. lycopersicum na dose de 80 mg/kg.

3.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 250-254, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37206730

RESUMO

Chronic Otitis Media-Squamosal type is an erosive process, which when confined to ossicular chain causes varying degrees of hearing impairment. As the disease progresses to involve surrounding vital structures, it causes various complications like facial palsy, vertigo, mastoid abscess, which are more common than the other intracranial complications, and require a definitive surgical intervention i.e., mastoidectomy at the earliest. A retrospective study on 60 patients who had been operated for squamosal type were analysed for the demographics, symptomatology, intraoperative extent of cholesteatoma, type of mastoidectomy done, various graft materials used for reconstruction, post operatively for graft uptake, hearing improvement and the results were analysed using ChOLE classification of cholesteatoma. Although Intact Canal Wall mastoidectomy had improved post op PTA values, there was no significant difference in the Air-Bone gap closure when Intact Canal Wall mastoidectomy was compared to Canal Wall Down Mastoidectomy.

4.
Braz J Biol ; 84: e254552, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35137848

RESUMO

Anti-tuberculosis drugs are reported to cause hepatotoxicity, which varies from asymptomatic rise of the hepatic enzymes. Hepatoprotective plants plays important role to protect liver. This study investigated the hepatoprotective potential of the Solanum lycopersicum in rats intoxicated with Isoniazid and Rifampicin (INH+RIF) to induce hepatotoxicity. Thirty wistar albino rats were divided into five groups of six animals each. Group 1 rats were kept control while groups II, III, IV and V were administered with INH+RIF (75+150 mg/kg) orally, for seven consecutive days. For treatment, rats in group III received silymarin while animals in group IV and V were provided with 40 mg/kg and 80 mg/kg of Solanum lycopersicum extract, respectively. On day 0 and 8th blood samples were collected for the analysis of hepatic biomarkers. The data were subjected to one-way ANOVA and Bonferroni's post hoc test for statistical analysis. Hepatotoxicity induced by INH+RIF resulted in significant elevation of serum hepatic enzymes including Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP), and total bilirubin while decreased the albumin level. The Solanum lycopersicum at dose of 80 mg/kg significantly reduced the hepatic enzymes AST, ALT, ALP and bilirubin while the albumin level was significantly increased. The treatment had non-significant effect on body and liver weight. Drug induced hepatotoxicity can be effectively treated with Solanum lycopersicum at 80 mg/kg dose.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Solanum lycopersicum , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Isoniazida/toxicidade , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Rifampina/toxicidade
5.
Heliyon ; 7(2): e05988, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33644434

RESUMO

High temperature induced by climatic fluctuations are an important threat for plant growth, development and quality of agricultural produces. Adaptableness to environmental changes generally derives from a large set of genetic traits affecting physio-morphological, biochemical and agronomic parameters. Therefore, the identification of genotypes with higher yield and good quality parameters at high temperatures is becoming increasingly necessary for future breeding programs. Here, we analyzed the performance of different tomato genotypes grown under elevated temperatures in terms of yield and nutritional quality of the fruit. High temperature stress was induced from flower initiation to maturity stage by keeping the pots in a temperature controlled green house facility for 45 days. The quality and yield parameters were taken at the harvesting stage. Starch and soluble sugar concentration in the leaves of tomato genotypes showed significant reduction in its amount under heat stress. Titrable acidity (TA), total soluble solids (TSS) and ascorbic acid content of tomato fruits were highest under high temperature conditions compared to ambient condition but lycopene content decreased with rise in temperature. The yield attributes viz., number of fruits/plant, fruit set %, average fruit weight (g), yield per plant (g/plant) were significantly lower for Arka Saurabh, Arka Rakshak and Pusa Rohini when compared to other genotypes under study. Molecular characterization of selected 22 tomato genotypes were assessed using 25 simple sequence repeat (SSR) markers. Phylogenetic tree was constructed by the unweighted neighbour-joining method (UPGMA) using NTSYSpc cluster analysis software. The Jaccard's similarity matrix was constructed using the SIMQUAL method using UPGMA algorithm in NTSYSpc. Jaccard's similarity matrix among these tomato genotypes ranged from a minimum of 0.22 to a maximum of 1 with an average genetic similarity of 0.67. Hence this study has importance in identifying genotypes that could maintain good quality and higher yield under high temperature condition.

6.
Int J Biol Macromol ; 163: 1037-1043, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32668305

RESUMO

Enzymatic deconstruction of chitin to chitobiose is of significant interest in view of its various biological applications. Here we report detailed insights into the chitin degradation by chitinase-E from a chitinolytic bacterium Chitiniphilus shinanonensis (CsChiE). CsChiE was optimally active at 50 °C in 50 mM sodium phosphate pH-7.0. It showed a kcat and overall catalytic efficiency (Kcat/Km) as 3.9 × 103 s-1 and 0.6 × 103 s-1 mg-1 mL, respectively, on colloidal chitin (CC). CsChiE efficiently hydrolyzed crystalline polymers like α-, ß- and CC and released chitobiose as the predominant product (11.3 mM on CC). Further, CsChiE displayed substantial activity towards the unmilled crab shell chitin waste (chitin-flakes) and generated chitobiose. Activity studies on chitooligosaccharides revealed that CsChiE produced chitobiose as the major product. Our results indicate that the multi-modular CsChiE is a non-processive exo-chitinase which is more suitable to generate chitobiose from a variety of chitinous substrates including unprocessed chitin-flakes.


Assuntos
Betaproteobacteria/metabolismo , Quitina/metabolismo , Quitinases/metabolismo , Dissacarídeos/metabolismo , Quitina/análogos & derivados , Quitosana , Hidrólise , Oligossacarídeos/metabolismo , Especificidade por Substrato
7.
J Glaucoma ; 29(8): 689-693, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32366779

RESUMO

PRéCIS:: A large cohort undergoing cataract extraction was retrospectively analyzed to ascertain the degree of real-world intraocular pressure (IOP) reduction in normal eyes and those with glaucoma, and a predictive formula was developed. PURPOSE: The purpose of this study was to define the real-world degree of IOP reduction after cataract extraction to guide its role as an isolated intervention for glaucoma. MATERIALS AND METHODS: A retrospective analysis was carried out of clinical data collected in 8 clinical sites in the United Kingdom from an electronic medical record system between January 2006 and May 2015. A total of 20,508 eyes without known pathology and 2251 eyes from patients with glaucoma undergoing phacoemulsification and intraocular lens insertion were included. Eyes with intraoperative complications, undergoing additional procedures, axial lengths outside 22 to 26.5 mm, preoperative IOP under 6 mm Hg or over 30 mm Hg, and copathology, except for amblyopia or glaucoma, were excluded. The main outcome measure was the change in preoperative IOP compared with the next recorded visit for up to 12 weeks. RESULTS: In eyes without pathology, the mean reduction in IOP was 1.40 mm Hg (±3.74) compared with 1.03 (±5.02), P-value <0.001, in eyes with a diagnosis of glaucoma. A multiple linear regression model identified preoperative IOP, a glaucoma diagnosis, preoperative corrected visual acuity, age, and axial length as determinants of IOP reduction. The model was validated against an independent cohort. CONCLUSIONS: We quantify mean IOP reduction achieved in a real-world setting from cataract surgery alone. In glaucomatous eyes where angle closure is not differentiated, phacoemulsification alone yields only a modest reduction of IOP.


Assuntos
Glaucoma/fisiopatologia , Pressão Intraocular/fisiologia , Implante de Lente Intraocular , Facoemulsificação , Pseudofacia/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Glaucoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Hipotensão Ocular/fisiopatologia , Hipotensão Ocular/cirurgia , Estudos Retrospectivos , Tonometria Ocular
9.
Mater Sci Eng C Mater Biol Appl ; 98: 746-752, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30813080

RESUMO

The electrochemical study of Catechol (CC) was studied in presence of Hydroquinone (HQ) using poly(murexide) modified glassy carbon electrode (MGCE) by cyclic voltammetric study. The modified electrode exhibited good affirmative response towards the electro chemical oxidation of CC in presence of HQ in 0.2 M phosphate buffer solution at the physiological of pH 7.4. The influence of scan rate, concentration and pH parameters were examined with the cyclic voltammetric method. The modified electrode showed good selectivity and sensitivity with an advantage of interference study and free determination of selected analytes in this experiment. Finally a simple, sensitive and selective method was developed for the determination of dihydroxybenzene isomeric compounds.


Assuntos
Carbono/química , Catecóis/química , Eletroquímica/métodos , Eletrodos , Hidroquinonas/química , Polímeros/química , Ferrocianetos/química
10.
Curr Eye Res ; 44(5): 533-540, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30577706

RESUMO

AIMS: To evaluate retinal vasculature changes in primary open-angle glaucoma (POAG) and whether the functional visual loss correlates with parameters obtained using optical coherence tomography angiography (OCTA). MATERIALS AND METHODS: OCT and OCTA images were collected from 116 POAG eyes and 40 normal eyes in a prospective, cross-sectional observational study. Glaucomatous eyes were further divided into three groups according to a Glaucoma Staging System. Measurements of macular vessel density, ganglion cell complex (GCC), and disk retinal nerve fiber layer (RNFL) thickness were compared among groups. RESULTS: The macular vessel density, GCC, and RNFL are significantly reduced in POAG compared to normal eyes that also corresponds to the severity of glaucoma (Kruskal-Wallis test with Dunnett's correction; p < 0.0001). Visual field mean deviation correlates significantly with macular vessel density (p = 0.0028, r = 0.3), GCC (p < 0.0001, r = 0.6), and RNFL (p = 0.008, r = 0.36) in POAG. There are significant correlations between GCC and RNFL (p < 0.0001, r = 0.76) as well as macular vessel density (p < 0.0001, r = 0.48). Increased age also correlates with reduced macular vessel density in both normal (p = 0.0002, r = 0.49) and glaucomatous eyes (p < 0.0001, r = 0.48), but a greater proportionate reduction of vessel density is seen in glaucomatous eyes. CONCLUSION: Reduced macular vessel density occurs in POAG despite of age-related changes, which also correlates with reductions in RNFL and GCC measurements. OCTA can detect microstructural defects and offers potential to facilitate diagnosis of glaucoma.


Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Disco Óptico/irrigação sanguínea , Vasos Retinianos/fisiopatologia , Idoso , Envelhecimento/fisiologia , Capilares/fisiopatologia , Estudos Transversais , Feminino , Angiofluoresceinografia , Humanos , Pressão Intraocular/fisiologia , Masculino , Fibras Nervosas/patologia , Disco Óptico/patologia , Estudos Prospectivos , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica , Testes de Campo Visual , Campos Visuais/fisiologia
11.
Microbiol Res ; 217: 91-100, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30384912

RESUMO

Plant growth promoting rhizobacteria (PGPR) promote plant growth and activate defense response against phytopathogens. At the subcellular level plant-PGPR interaction is less understood, which would be essential for future improvement(s) of PGPR formulations. In a rigorous screening process, that also involved efficient PGPR strains, Bacillus sonorensis RS4 was selected to study partner-triggered interactions. The potential of B. sonorensis RS4 to improve growth of groundnut, efficiency to colonize roots, and influence on root topology was assessed. Twenty four cell wall proteins of B. sonorensis RS4 [in presence of groundnut root exudates (REs)], and 22 groundnut root proteins (in RS4-bacterized plants) were differentially expressed. The alterations in cell wall proteins of B. sonorensis RS4 were primarily related to the amino acids synthesis, chemotaxis, antioxidant-metabolism, carbohydrate metabolism, transporters, and antibiosis-related secondary metabolites. Root proteins that were differentially expressed during the interaction may be involved in plant growth, defense responses, and in transportation. The changes in B. sonorensis RS4 cell wall proteome and groundnut root proteome, suggest that at least a part of the proteome changes triggered by each of the partners appear to play a significant role in helping each other akin to symbiosis.


Assuntos
Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Desenvolvimento Vegetal , Proteoma/metabolismo , Aminoácidos/biossíntese , Antibiose , Antioxidantes/metabolismo , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/isolamento & purificação , Metabolismo dos Carboidratos , Quimiotaxia/fisiologia , Solanum lycopersicum/microbiologia , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Rizosfera , Metabolismo Secundário , Sementes/microbiologia , Simbiose
12.
Int J Hyperthermia ; 35(1): 518-527, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30208750

RESUMO

Despite an understanding that a major effect of cold exposure is a fall in core body temperature which is responsible for the observed decrements in the performance, it is surprising that thermogenic supplements are seldom evaluated to verify if they can aid in improving the performance during cold exposure. Following evidence from our previous study indicating the ability of pepper and cinnamon to improve cold endurance, we investigated further here if the improved endurance had advantages in real time where they could positively affect cognitive performance (assessed by Novel object test) when exposed to cold in albino wistar rats. In order to delineate if the observed improvement if any, was due to their cognitive enhancing ability or thermogenic potential, distinctive room temperature (RT) and cold temperature (CT) groups were used. Cold exposure impaired cognitive performance which improved following treatment with both the spices. We noted an increased rate of cold adaptive thermogenesis in CT treated group as evidenced by an elevated norepinephrine, free fatty acid levels in blood, increased expression of UCP1 in brown adipose tissue, the net effect being a decreased fall in the core body temperature. Absence of any notable effect in these parameters in the RT treated group ascertained that at least in the current experimental set up the observed improvement in performance in CT treated group is due to the thermogenic potential of the spices alone. In conclusion, our results demonstrate that the cognitive impairment caused by exposure to cold can be effectively countered by agents with thermogenic potential.


Assuntos
Cinnamomum zeylanicum/química , Disfunção Cognitiva/tratamento farmacológico , Temperatura Baixa/efeitos adversos , Piper nigrum/química , Termogênese/efeitos dos fármacos , Animais , Humanos , Masculino , Ratos , Ratos Wistar
13.
Front Plant Sci ; 9: 1154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30158943

RESUMO

Plants being sessile are under constant threat of multiple abiotic and biotic stresses within its natural habitat. A combined stress involving an abiotic and a biotic factor reportedly increases susceptibility of the plants to pathogens. The emerging threat, collar rot disease of chickpea (caused by Sclerotium rolfsii Sacc.) is reported to be influenced by soil moisture condition (SMC). Hence, we studied the influence of differential SMC viz. upper optimum (100%), optimum (80%), lower optimum (60%), and limiting (40%) soil moisture conditions on colonization and collar rot development over the course of infection in two chickpea cultivars, Annigeri (susceptible to collar rot) and ICCV 05530 (moderately resistant to collar rot). Disease incidence was found to be directly proportional to increase in soil moisture (R2 = 0.794). Maximum incidence was observed at 80% SMC, followed by 100 and 60% SMC. Expression of genes (qPCR analysis) associated with host cell wall binding (lectin) and degradation viz. endopolygalacturonase-2, endoglucosidase, and cellobiohydrolase during collar rot development in chickpea were relatively less at limiting soil moisture condition (40%) as compared to optimum soil moisture condition (80%). As compared to individual stress, the expression of defense response genes in chickpea seedlings were highly up-regulated in seedlings challenged with combined stress. Our qPCR results indicated that the expression of defense-related genes in chickpea during interaction with S. rolfsii at low SMC was primarily responsible for delayed disease reaction. Involvement of moisture and biotic stress-related genes in combined stress showed a tailored defense mechanism.

14.
Carbohydr Polym ; 199: 11-19, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143111

RESUMO

HarpinPss, an elicitor from Pseudomonas syringae pv. syringae, induces systemic acquired resistance in non-host plants, providing resistance to phytopathogens. Poor assimilation of harpinPss is a major constraint in foliar application as biopesticide. We, therefore, prepared harpinPss-loaded chitosan nanoparticles (H-CSNPs) to improve permeability and bio-availability of harpinPss in tomato. H-CSNPs showed high encapsulation efficiency (90%), improved stability (p < 0.01) and bioavailability of harpinPss (p < 0.01). Treatment with H-CSNPs resulted in sustained induction of peroxidase, phenylalanine ammonia lyase and decreased Rhizoctonia solani infection (p < 0.05). Transcripts of several genes involved in defense response were differentially expressed in harpinPss, CSNPs and H-CSNPs treatments. While, genes involved in jasmonic acid (JA) metabolism were up-regulated during harpinPss and H-CSNP spray treatments, indicating the role of JA pathway in triggering harpin-mediated defense responses. Furthermore, the entry of CSNPs into the cell and localization of harpinPss into chloroplast was tracked using rhodamine-labelled CSNPs encapsulated with GFP tagged harpinPss. The results of this study indicate use of H-CSNPs is effective for sustained-release of harpinPss and provides resistance for prolonged duration.

16.
Biochemistry ; 57(29): 4325-4337, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29939724

RESUMO

Understanding features that determine transglycosylation (TG) activity in glycoside hydrolases is important because it would allow the construction of enzymes that can catalyze controlled synthesis of oligosaccharides. To increase TG activity in two family 18 chitinases, chitinase D from Serratia proteamaculans ( SpChiD) and chitinase A from Serratia marcescens ( SmChiA), we have mutated residues important for stabilizing the reaction intermediate and substrate binding in both donor and acceptor sites. To help mutant design, the crystal structure of the inactive SpChiD-E153Q mutant in complex with chitobiose was determined. We identified three mutations with a beneficial effect on TG activity: Y28A (affecting the -1 subsite and the intermediate), Y222A (affecting the intermediate), and Y226W (affecting the +2 subsite). Furthermore, exchange of D151, the middle residue in the catalytically important DXDXE motif, to asparagine reduced hydrolytic activity ≤99% with a concomitant increase in apparent TG activity. The combination of mutations yielded even higher degrees of TG activity. Reactions with the best mutant, SpChiD-D151N/Y226W/Y222A, led to rapid accumulation of high levels of TG products that remained stable over time. Importantly, the introduction of analogous mutations at the same positions in SmChiA (Y163A equal to Y28A and Y390F similar to Y222A) had similar effects on TG efficiency. Thus, the combination of the decreasing hydrolytic power, subsite affinity, and stability of intermediate states provides a powerful, general strategy for creating hypertransglycosylating mutants of retaining glycoside hydrolases.


Assuntos
Quitinases/química , Quitinases/metabolismo , Serratia marcescens/enzimologia , Sequência de Aminoácidos , Quitinases/genética , Cristalografia por Raios X , Dissacarídeos/metabolismo , Glicosilação , Hidrólise , Modelos Moleculares , Mutação , Alinhamento de Sequência , Serratia/química , Serratia/enzimologia , Serratia/metabolismo , Infecções por Serratia/microbiologia , Serratia marcescens/química , Serratia marcescens/genética , Serratia marcescens/metabolismo
17.
J Plant Physiol ; 184: 20-7, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26202445

RESUMO

The nucleus is the maestro of the cell and is involved in the modulation of cell signaling during stress. We performed a comprehensive nuclear proteome analysis of Citrus sinensis during interaction with host (Xanthomonas citri pv. citri-Xcc) and non-host (Xanthomonas oryzae pv. oryzae-Xoo) pathogens. The nuclear proteome was obtained using a sequential method of organelle enrichment and determined by nano-LC-MS/MS analysis. A total of 243 proteins accumulated differentially during citrus-Xanthomonas interaction, belonging to 11 functional groups, with signaling and transcription-related proteins dominating. MADS-box transcription factors, DEAD-box RNA helicase and leucine aminopeptidase, mainly involved in jasmonic acid (JA) responses, were in high abundance during non-host interaction (Xoo). Signaling-related proteins like serine/threonine kinase, histones (H3.2, H2A), phosphoglycerate kinase, dynamin, actin and aldolase showed increased accumulation early during Xoo interaction. Our results suggest that there is a possible involvement of JA-triggered defense responses during non-host resistance, with early recognition of the non-host pathogen.


Assuntos
Citrus sinensis/genética , Citrus sinensis/microbiologia , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Proteínas de Plantas/genética , Proteoma/genética , Fatores de Transcrição/genética , Xanthomonas/fisiologia , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatografia Líquida , Citrus sinensis/imunologia , Citrus sinensis/metabolismo , Imunidade Vegetal , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Especificidade da Espécie , Espectrometria de Massas em Tandem , Fatores de Transcrição/metabolismo
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 130: 164-77, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24792193

RESUMO

The stable geometry of 2-hydroxy-4-methoxyacetophenone is optimised by DFT/B3LYP method with 6-311++G(∗∗) and cc-pVTZ basis sets. The structural parameters, thermodynamic properties and vibrational frequencies of the optimised geometry have been determined. The effects of substituents (hydroxyl, methoxy and acetyl groups) on the benzene ring vibrational frequencies are analysed. The vibrational frequencies of the fundamental modes of 2-hydroxy-4-methoxyacetophenone have been precisely assigned and analysed and the theoretical results are compared with the experimental vibrations. 1H and 13C NMR isotropic chemical shifts are calculated and assignments made are compared with the experimental values. The energies of important MO's, the total electron density and electrostatic potential of the compound are determined. Various reactivity and selectivity descriptors such as chemical hardness, chemical potential, softness, electrophilicity, nucleophilicity and the appropriate local quantities are calculated.


Assuntos
Acetofenonas/química , Espectroscopia de Ressonância Magnética , Acetofenonas/síntese química , Algoritmos , Carbono/química , Elétrons , Hidrogênio/química , Ligação de Hidrogênio , Conformação Molecular , Oxigênio/química , Teoria Quântica , Software , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática , Relação Estrutura-Atividade , Propriedades de Superfície , Termodinâmica , Vibração
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 129: 466-77, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24755636

RESUMO

The structural parameters, thermodynamic properties and vibrational frequencies of the optimised geometry of trans-3-(trans-4-imidazolyl)acrylic acid have been determined from B3LYP methods with 6-311++G(**) and cc-pVTZ basis sets. The effects of substituents (acrylyl group) on the imidazole vibrational frequencies are analysed. The vibrational frequencies of the fundamental modes of trans-3-(trans-4-imidazolyl)acrylic acid have been precisely assigned and analysed and the theoretical results are compared with the experimental vibrations. (1)H and (13)C NMR isotropic chemical shifts are calculated and the assignments made are compared with the experimental values. The energies of important MO's of the compound are also determined from DFT method. The total electron density and electrostatic potential of the compound are determined by natural bond orbital analysis. Various reactivity and selectivity descriptors such as chemical hardness, chemical potential, softness, electrophilicity, nucleophilicity and the appropriate local quantities employing natural population analysis (NPA) are calculated.


Assuntos
Acrilatos/química , Imidazóis/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
20.
Arch Virol ; 159(3): 413-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24036956

RESUMO

Tobacco streak virus (TSV), a member of the genus Ilarvirus (family Bromoviridae), has a tripartite genome and forms quasi-isometric virions. All three viral capsids, encapsidating RNA 1, RNA 2 or RNA 3 and subgenomic RNA 4, are constituted of a single species of coat protein (CP). Formation of virus-like particles (VLPs) could be observed when the TSV CP gene was cloned and the recombinant CP (rCP) was expressed in E. coli. TSV VLPs were found to be stabilized by Zn(2+) ions and could be disassembled in the presence of 500 mM CaCl2. Mutational analysis corroborated previous studies that showed that an N-terminal arginine-rich motif was crucial for RNA binding; however, the results presented here demonstrate that the presence of RNA is not a prerequisite for assembly of TSV VLPs. Instead, the N-terminal region containing the zinc finger domain preceding the arginine-rich motif is essential for assembly of these VLPs.


Assuntos
Proteínas do Capsídeo/metabolismo , Ilarvirus/fisiologia , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Virossomos/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Análise Mutacional de DNA , Escherichia coli/genética , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Zinco/metabolismo , Dedos de Zinco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA