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101.
The present study was performed to investigate the possible role of carbon (C) and nitrogen (N) metabolism in adaptation of Indian mustard (Brassica juncea L.) growing under ambient (370 ± 15 ppm) and elevated CO2 (700 ± 15 ppm), and jointly in elevated CO2 and temperature (30/22 °C for day/night). The key enzymes responsible for C–N metabolism were studied in different samples of Brassica juncea L. collected from ambient (AMB), elevated (ELE) and ELExT growth conditions. Total percent amount of C and N in leaves were particularly estimated to establish a clear understanding of aforesaid metabolism in plant adaptation. Furthermore, key morphological and physiological parameters such as plant height, leaf area index, dry biomass, net photosynthetic rate, stomatal conductance, transpiration, total protein and chlorophyll contents were also studied in relation to C/N metabolism. The results indicated that the C-metabolizing enzymes, such as (ribulose-1,5-bisphosphate carboxylase/oxygenase, phosphoenolpyruvate carboxylase, malate dehydrogenase, NAD-malic enzyme, NADP-malic enzyme and citrate synthase) and the N-metabolizing enzymes, such as (aspartate amino transferase, glutamine synthetase, nitrate reductase and nitrite reductase) showed significantly (P < 0.05) higher activities along with the aforesaid physiological and biochemical parameters in order of ELE > ELExT > AMB growth conditions. This is also evident by significant (P < 0.05) increase in percent contents of C and N in leaves as per said order. These findings suggested that improved performance of C–N metabolism could be a possible approach for CO2 assimilation and adaptation in Brassica juncea L. against elevated CO2 and temperature prevailing in climate change scenarios. 相似文献
102.
103.
Wang M Gao M Steele BL Glick-Wilson BE Brown-Proctor C Shekhar A Hutchins GD Zheng QH 《Bioorganic & medicinal chemistry letters》2012,22(14):4713-4718
GSK189254 and its corresponding precursor GSK185071B were synthesized from 3-methoxyphenylacetic acid with 6-chloropyridine-3-carbolic acid or 6-chloronicotinamide in 8 and 7 steps with either 6% or 7% and either 14% or 16% yield, respectively. [(11)C]GSK189254 was prepared from GSK185071B with [(11)C]CH(3)OTf through N-[(11)C]methylation and isolated by HPLC combined with solid-phase extraction (SPE) in 50-60% radiochemical yield based on [(11)C]CO(2) and decay corrected to end of bombardment (EOB), with 370-740 GBq/μmol specific activity at EOB. 相似文献
104.
Jogender Mehla Monika Pahuja Shekhar M. Dethe Amit Agarwal Yogendra Kumar Gupta 《Neurochemistry international》2012
Evolvulus alsinoides, also known as Shankpushapi, is a commonly used traditional medicine for enhancing memory. We evaluated the in vitro free radical scavenging and enzymes [acetylcholinesterase, butyrylcholinestrase, glycogen synthase kinase-3-β (GSK-3-β), rho kinase (ROCK II), prolyl endopeptidase (PEP), catechol-O-methyl transferase (COMT) and lipoxygenase (LOX)] inhibitory activities of aqueous and hydro-alcoholic extracts of E. alsinoides. Hydro-alcoholic extract of E. alsinoides demonstrated more free radical scavenging activity as compared to aqueous extract. Hydro-alcoholic extract also showed higher cholinesterase, GSK-3-β, ROCK II, PEP, COMT and LOX enzyme inhibitory activities as compared to aqueous extract. Phytochemical analysis revealed more flavanoids in hydro-alcoholic extract as compared to aqueous extract but no significant difference in phenolic content of the two extracts was observed. Based on in vitro data, hydro-alcoholic extract (100, 300 and 500 mg/kg, p.o.) was selected for in vivo study in intracerebroventricularly injected streptozotocin (STZ) induced cognitive impairment in male Wistar rats. Elevated plus maze, passive avoidance and Morris water maze were used for assessment of cognitive function on 14th, 21st and 28th day after STZ injection. Oxidative stress parameters (malondialdehyde, reduced glutathione, nitric oxide levels and superoxide dismutase activity), cholinergic dysfunction and rho kinase (ROCK II) expression were studied in cerebral cortex and hippocampus of rat brain at the end of the study. Hydro-alcoholic extract of E. alsinoides dose dependently prevented STZ induced cognitive impairment by reducing the oxidative stress, improving cholinergic function and preventing the increase in rho kinase expression. The results suggest an anti-Alzheimer potential of hydro-alcoholic extract of E. alsinoides. 相似文献
105.
The present study evaluates the role of Pseudomonas
putida NBRIC19 in alleviating biotic stress of Parthenium
hysterophorus (Parthenium) in Triticum
aestivum. Due to presence of Parthenium there was 43.76, 53.08 and 78.65% inhibition in root length, shoot length and dry weight of
wheat respectively. This inhibition was recovered when P. putida NBRIC19 treatment resulted in 52.29, 28.73 and 76.31% increase in root length, shoot length and dry weight respectively as
compared to control. P. putida NBRIC19 was able to form more biofilm under toxic environment of allelochemicals and enhanced expression of stress responsive
genes in wheat. Inoculated wheat plants showed lower activity of catalase and ascorbate peroxidase under biotic stress of
Parthenium indicating that inoculated plants felt less stress as compared to uninoculated plants. Microbial community structure
in bacterized and nonbacterized wheat rhizosphere in presence and absence of Parthenium, was investigated using Biolog. There
was significant increase in microbial diversity in P. putida NBRIC19 bacterized wheat rhizosphere. Functional microbial diversity revealed that P. putida NBRIC19 had shifted the microflora in such a manner that utilization of phytotoxic allelochemicals increased to lessen its
toxic effect and finally it resulted in better growth of wheat in presence of Parthenium. Principal component analysis showed
that microbial community function in nonbacterized wheat rhizosphere in presence (WPC) and absence (WC) of Parthenium is totally
different from each other but due to P. putida NBRIC19 treatment there was close clustering of WPT and WT indicating a total shift in microbial community structure. 相似文献
106.
T-bet deficiency facilitates airway colonization by Mycoplasma pulmonis in a murine model of asthma 总被引:3,自引:0,他引:3
Bakshi CS Malik M Carrico PM Sellati TJ 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(3):1786-1795
Epidemiological and clinical evidence suggest a correlation between asthma and infection with atypical bacterial respiratory pathogens. However, the cellular and molecular underpinnings of this correlation remain unclear. Using the T-bet-deficient (T-bet(-/-)) murine model of asthma and the natural murine pathogen Mycoplasma pulmonis, we provide a mechanistic explanation for this correlation. In this study, we demonstrate the capacity of asthmatic airways to facilitate colonization by M. pulmonis and the capacity of M. pulmonis to exacerbate symptoms associated with acute and chronic asthma. This mutual synergism results from an inability of T-bet(-/-) mice to mount an effective immune defense against respiratory infection through release of IFN-gamma and the ability of M. pulmonis to trigger the production of Th2-type cytokines (e.g., IL-4 and IL-5), and Abs (e.g., IgG1, IgE, and IgA), eosinophilia, airway remodeling, and hyperresponsiveness; all pathophysiological hallmarks of asthma. The capacity of respiratory pathogens such as Mycoplasma spp. to dramatically augment the pathological changes associated with asthma likely explains their association with acute asthmatic episodes in juvenile patients and with adult chronic asthmatics, >50% of whom are found to be PCR positive for M. pneumoniae. In conclusion, our study demonstrates that in mice genetically predisposed to asthma, M. pulmonis infection elicits an inflammatory milieu in the lungs that skews the immune response toward the Th2-type, thus exacerbating the pathophysiological changes associated with asthma. For its part, airways exhibiting an asthmatic phenotype provide a fertile environment that promotes colonization by Mycoplasma spp. and one which is ill-equipped to kill and clear respiratory pathogens. 相似文献
107.
Aspergillus
niger isolated from soil and effluent of leather tanning mills had higher activity to remove chromium. The potency of Aspergillus
niger was evaluated in shake flask culture by absorption of chromium at pH 6 and temperature 30°C. The results of the study indicated
removal of more than 75% chromium by Aspergillus
niger determined by diphenylcarbazide colorimetric assay and atomic absorption spectrophotometry after 7 days. Study of microbial
Cr(VI) reduction and identification of reduction intermediates has been hindered by the lack of analytical techniques that
can identify the oxidation state with subcellular spatial resolution. Therefore, removal of chromium was further substantiated
by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX),
which indicated an accumulation of chromium in the fungal mycelium. 相似文献
108.
Superoxide dismutase B gene (sodB)-deficient mutants of Francisella tularensis demonstrate hypersensitivity to oxidative stress and attenuated virulence
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Bakshi CS Malik M Regan K Melendez JA Metzger DW Pavlov VM Sellati TJ 《Journal of bacteriology》2006,188(17):6443-6448
A Francisella tularensis live vaccine strain mutant (sodB(Ft)) with reduced Fe-superoxide dismutase gene expression was generated and found to exhibit decreased sodB activity and increased sensitivity to redox cycling compounds compared to wild-type bacteria. The sodB(Ft) mutant also was significantly attenuated for virulence in mice. Thus, this study has identified sodB as an important F. tularensis virulence factor. 相似文献
109.
Davis S Deo SH Barlow M Yoshishige D Farias M Caffrey JL 《American journal of physiology. Heart and circulatory physiology》2006,291(5):H2318-H2326
The cardiac enkephalin, methionine-enkephalin-arginine-phenylalanine (MEAP), alters vagally induced bradycardia when introduced by microdialysis into the sinoatrial (SA) node. The responses to MEAP are bimodal; lower doses enhance bradycardia and higher doses suppress bradycardia. The opposing vagotonic and vagolytic effects are mediated, respectively, by delta(1) and delta(2) phenotypes of the same receptor. Stimulation of the delta(1) receptor reduced the subsequent delta(2) responses. Experiments were conducted to test the hypothesis that the delta-receptor interactions were mediated by the monosialosyl ganglioside GM-1. When the mixed agonist MEAP was evaluated after nodal GM-1 treatment, delta(1)-mediated vagotonic responses were enhanced, and delta(2)-mediated vagolytic responses were reduced. Prior treatment with the delta(1)-selective antagonist 7-benzylidenaltrexone (BNTX) failed to prevent attrition of the delta(2)-vagolytic response or restore it when added afterward. Thus the GM-1-mediated attrition was not mediated by delta(1) receptors or increased competition from delta(1)-mediated vagotonic responses. When GM-1 was omitted, deltorphin produced a similar but less robust loss in the vagolytic response. In contrast, however, to GM-1, the deltorphin-mediated attrition was prevented by pretreatment with BNTX, indicating that the decline in response after deltorphin alone was mediated by delta(1) receptors and that GM-1 effectively bypassed the receptor. Whether deltorphin has intrinsic delta(1) activity or causes the release of an endogenous delta(1)-agonist is unclear. When both GM-1 and deltorphin were omitted, the subsequent vagolytic response was more intense. Thus GM-1, deltorphin, and time all interact to modify subsequent delta(2)-mediated vagolytic responses. The data support the hypothesis that delta(1)-receptor stimulation may reduce delta(2)-vagolytic responses by stimulating the GM-1 synthesis. 相似文献
110.
Vijayakrishnan S Qamra R Verma CS Sen R Mande SC 《Journal of biomolecular structure & dynamics》2006,23(4):365-376
The ubiquitously occurring chaperonins consist of a large tetradecameric Chaperonin-60, forming a cylindrical assembly, and a smaller heptameric Chaperonin-10. For a functional protein folding cycle, Chaperonin-10 caps the cylindrical Chaperonin-60 from one end forming an asymmetric complex. The oligomeric assembly of Chaperonin-10 is known to be highly plastic in nature. In Mycobacterium tuberculosis, the plasticity has been shown to be modulated by reversible binding of divalent cations. Binding of cations confers rigidity to the metal binding loop, and also promotes stability of the oligomeric structure. We have probed the conformational effects of cation binding on the Chaperonin-10 structure through fluorescence studies and molecular dynamics simulations. Fluorescence studies show that cation binding induces reduced exposure and flexibility of the dome loop. The simulations corroborate these results and further indicate a complex landscape of correlated motions between different parts of the molecule. They also show a fascinating interplay between two distantly spaced loops, the metal binding "dome loop" and the GroEL-binding "mobile loop", suggesting an important cation-mediated role in the recognition of Chaperonin-60. In the presence of cations the mobile loop appears poised to dock onto the Chaperonin-60 structure. The divalent metal ions may thus act as key elements in the protein folding cycle, and trigger a conformational switch for molecular recognition. 相似文献