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41.
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Protoplasts isolated from the mycobiont of a cultured lichen Usnea ghattensis were fused with protoplasts of the fungus Aspergillus nidulans in order to increase the growth rate of the cultured lichen mycobiont in vitro. The maximum protoplast yield (102 × 104/g fresh cell mass) was reached in citrate buffer with 50 mmol/L 2-sulfanylethanol (‘2-mercaptoethanol’) containing 0.1 %
Novozym after 1.5 h at pH 5 and ≤25 °C. The increase in the concentration of the above effectors or the addition of others
(e.g., MgSO4) as well as increase in time, shaking frequency, etc. caused the lower yield of protoplasts. The fused protoplasts were regenerated after transfer to malt extract-yeast extract
medium and produced, after a 45-d cultivation, a fresh cell mass of 0.232 g (from starting 0.3 g) along with the lichen substance
usnic acid. 相似文献
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Phosphate detection has garnered widespread attention due to its biological and environmental impact. Among several optical techniques, time-resolved fluorescence (TRF) provides a sensitive way for the discrimination of analytes in a complex mixture as it exhibits less interference from the background, therefore providing a high signal-to-noise ratio. The sensitization of rare earth metal (REM) ions by semiconducting quantum dots (QDs) can help the former overcome the drawback of low absorption coefficient, therefore allowing exploitation of the additional advantage of the REM, namely the long-excited state lifetime. Here, we have developed a TRF-based sensor array consisting of three QDs, i.e. MoS2, WS2 and MoSe2 as energy sensitizers for Tb3+ ions. Different QDs possess variable energy transfer abilities for Tb3+ ions. Therefore, they can be used to discriminate phosphates. It was also observed that CrO42− can competitively bind to Tb3+ and further enhance the efficiency of the sensor array so that it could discriminate six different phosphates at 200 μM concentration in aqueous as well as serum medium with a detection limit of 10 μM in aqueous medium. Therefore, the sensitivity of the TRF-based sensor array is rarely compromised in a complex mixture, which is advantageous over a fluorescence-based sensor array. 相似文献
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46.
S. K. Yasin Baksh Ravindra Donde Jitendra Kumar Mitadru Mukherjee Jitendriya Meher Lambodar Behera Sushanta Kumar Dash 《Physiology and Molecular Biology of Plants》2021,27(3):543
Rice is an important source of calorie for the growing world population. Its productivity, however is affected by climatic adversities, pest attacks, diseases of bacterial, viral and fungal origin and many other threats. Developing cultivars that are high yielding and stress resilient seems a better solution to tackle global food security issues. This study investigates the potential resistance of 24 rice cultivars against Xanthomonas oryzae pv. Oryzae (Xoo) infection that causes bacterial leaf blight disease and submergence stress. Bacterial leaf blight (BLB) resistance genes (Xa4, xa5, xa13, Xa21, Xa38) and submergence tolerance (Sub1) gene specific markers were used to determine the allelic status of genotypes. The results displayed presence of Xa4 resistance allele (78.95%), xa5 (15.79%) but xa13 and Sub1 tolerance allele were not found in any genotype. However, a new allele for Xa21 (84.21%) and Xa38 (10.52%) were identified in several genotypes. Phenotypic screening for both stress conditions was done to record the cultivars response. None of the genotypes showed resistance against Xoo, although varieties viz., Tapaswini and Konark showed moderate susceptibility. Likewise, survival percentage of genotypes under submergence stress varied from 0 to 100%. Tolerant checks FR13A (100%) and Swarna Sub1 (97.78%) exhibited high survival rate, whereas among genotypes, Gayatri (57.78%) recorded high survivability even though it lacked Sub1 tolerant its genetic background. A total of six trait specific STS and two SSR markers generated an average of 2.38 allele per locus. Polymorphism information content (PIC) value ranged from 0.08 to 0.42 with an average of 0.20. Structure analysis categorized 24 genotypes into two sub-populations, which was in correspondence with Nei’s genetic distance-based NJ tree and principal co-ordinate analysis (PCoA). Swarna Sub1 could be differentiated clearly from BLB resistant check, IRBB60 and other 22 genotypes without having Sub1 gene. Analysis of molecular variance (AMOVA) revealed more genetic variation within population than among population. Principal component analysis (PCA) showed that 9 morphological traits collectively explained 76.126% of total variation among all the genotypes studied. The information from this study would be useful in future breeding programs for pyramiding trait specific genes into high yielding cultivars that fall behind with respect to stress resilience. Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00951-1. 相似文献
47.
Performance of two dual chambered mediator-less microbial fuel cells (MFCs) was evaluated at different sludge loading rate (SLR) and feed pH. Optimum performance in terms of organic matter removal and power production was obtained at the SLR of 0.75 kg COD kg VSS−1 d−1. Maximum power density of 158 mW/m2 and 600 mW/m2 was obtained in MFC-1 (feed pH 6.0) and MFC-2 (feed pH 8.0), respectively. Internal resistance of the cell decreased with increase in SLR. When operated only with biofilm on anode, the maximum power density was 109.5 mW/m2 in MFC-1 and 459 mW/m2 in MFC-2, which was, respectively, 30% and 23.5% less than the value obtained in MFC-1 and MFC-2 at SLR of 0.75 kg COD kg VSS−1 d−1. Maximum volumetric power of 15.51 W/m3 and 36.72 W/m3 was obtained in MFC-1 and MFC-2, respectively, when permanganate was added as catholyte. Higher feed pH (8.0) favoured higher power production. 相似文献
48.
Respiratory syncytial virus infection activates STAT signaling in human epithelial cells 总被引:9,自引:0,他引:9
Kong X San Juan H Kumar M Behera AK Mohapatra A Hellermann GR Mane S Lockey RF Mohapatra SS 《Biochemical and biophysical research communications》2003,306(2):616-622
Acute respiratory syncytial virus (RSV) infection causes airway inflammation and exacerbates asthma, but the mechanism of inflammation is poorly understood. The role of the STAT-signaling pathway in RSV infection in epithelial cells was examined in this study. DNA microarray analyses of RSV-infected human alveolar type II (A549) epithelial cells identified several genes whose expression was altered from -5.5 to +56.4-fold. Four of the highly expressed genes contained STAT-binding elements. In A549 and normal human bronchial epithelial cells (NHBE), RSV induced phosphorylation and nuclear translocation of STAT-1alpha that was abrogated when RSV attachment was blocked. Treatment with a JAK-2 inhibitor or transfection with dominant-negative STAT-1alpha blocked STAT-1alpha activation and RSV infection. RSV also activated STAT-3 and IL-6 specific antibodies blocked this activation. Thus, activation of the STAT-1alpha and STAT-3 pathways play a role in RSV infection. 相似文献
49.
Qualitative and quantitative studies of atmospheric fungal spores at a chloralkali factory, Jayashree Chemicals. were made
during 1993 employing culture plate and rotorod methods. A total of 57 sporulating fungal types, including three sterile mycelial
forms, were recorded by the culture plate method and 51 spore types, including the hyphal fragments and unidentified spores,
were recorded by the rotorod method. As to the seasonal variation, winter was found to be the greatest contributor of fungal
spores as compared to the summer and rainy season. Instead, when considering the hour of the day, the peak number of fungal
propagules was recorded at noon (12.00 h) followed by evening and morning values, an exception being recorded in winter months,
when maximum CFUs ofCladosporium were monitored in the morning. The seasonal variation in fungal concentration and composition was found to be influenced
by temperature, rainfall and relative humidity, whereas diurnal incidence was the effect of varying temperature and relative
humidity during day time only. Moderate temperature and relative humidity favoured the maximum fungal spore load in the atmosphere.Cladosporium, Nigrospora, Alternaria, Lasiodiplodia, Drechslera, Pestalotia, Curvularia, Epicoccum, Aspergillus, Penicillium andChaetomium were the commonest fungal spores in the factory area. 相似文献
50.
Santosh Kumar Behera Prashant Kumar Modi Gayathree Karthikkeyan Sameera Krishna Pervaje Ravishankar Pervaje Rajesh Raju Thottethodi Subrahmanya Keshava Prasad Yashwanth Subbannayya 《Bioinformation》2021,17(11):911
Kanchanara Guggulu (KG) is an important traditional medicine that is prescribed by the Ayurveda physicians for the treatment of swellings in various organs such as the thyroid, and lymph nodes. High-resolution mass-spectrometry-based metabolomics found metabolites in KG. LC-MS/MS-based metabolomics analysis of KG identified 2,579 compounds including quercetin and kaempferol derivatives. The molecular docking and dynamics analysis of quercetin pentaacetate with aldose reductase is documented for further consideration in drug discovery. 相似文献