Detection of S-nitrosothiol and nitrosylated proteins in Arachis hypogaea functional nodule: response of the nitrogen fixing symbiont.

To detect the presence of NO, ROS and RNS in nodules of crack entry legumes, we used Arachis hypogaea functional nodule. The response of two cognate partner rhizobia was compared towards NO and GSNO using S. meliloti and Bradyrhizobium sp NC921001. ROS, NO, nitrosothiol and bacteroids were detected by fluorescence microscopy. Redox enzymes and thiol pools were detected biochemically. Nitrosothiols were found to be present but ROS and NO were absent in A. hypogaea nodule. A number of S-nitrosylated proteins were also detected. The total thiol pool and most of the redox enzymes were low in nodule cytosolic extract but these were found to be high in the partner microorganisms indicating partner rhizobia could protect the nodule environment against the nitrosothiols. Both S. meliloti and Bradyrhizobium sp NC921001 were found to contain GSNO reductase. Interestingly, there was a marked difference in growth pattern between S. meliloti and Bradyrhizobium sp in presence of sodium nitroprusside (SNP) and S-nitrosoglutathione (GSNO). Bradyrhizobium sp was found to be much more tolerant to NO donor compounds than the S. meliloti. In contrast, S. meliloti showed resistance to GSNO but was sensitive to SNP. Together our data indicate that nodule environment of crack entry legumes is different than the nodules of infection mode entry in terms of NO, ROS and RNS. Based on our biochemical characterization, we propose that exchange of redox molecules and reactive chemical species is possible between the bacteroid and nodule compartment

Effect of Aqueous Extract of Leaf of Aegle marmelos on Testicular Activities in Rats

The aqueous extract of leaf of Aegle marmelos (Bael) at the dose 50 mg/100 g body weight resulted a significant diminution in the activities of key testicular steroidogenic enzymes along with low levels of plasma testosterone and relative wet weights of sex organs in respect to control without any significant alteration in general body growth. Germ cells numbers in different generation at stage VII of seminiferous epithelial cell cycle were diminished significantly after the treatment of the above extract. The above mentioned dose did not exhibit any toxicity in liver and kidney. Therefore, it may be predicted that the aqueous extract of leaf of Aegle marmelos has a potent antitesticular effect at a specific dose

Future prediction of existing glacial lake’s size in the Himalaya by Markov model and glacial surface topography

ABSTRACTThe number and size of glacial lakes are increasing at a higher rate in the Himalaya because of rapid global warming. These lakes are the potential future zones of glacial lake outburst flood (GLOF) risks to the downstream; hence, regular monitoring along with future prediction in lake size must be done to find possible zones of future risks. This research focuses on the future prediction of regional-scale glacial lake size in the entire Himalayan mountain range. Here, we used Landsat TM and OLI images, Google Earth imageries, Cartosat DEM, and SRTM DEM, and used some techniques: average lake size change rate, Markov model and glacial surface topography to extract glacial lake size change and future prediction of lake size. A total of 9675 individual glacial lakes were noticed during the study period (1990-2020), out of which the lakes present constantly throughout the study period (with size >0.01 km2) were added in this study. Additionally, out of 1646 numbers of constantly present lake throughout the study period, 751 moraine dam lakes were taken for the future prediction of lake size change using the Markov model. A total of 191, 167 and 393 lakes were predicted as increase at a higher rate (Fast increase-FI), decrease at a lower rate (slow decrease-SD) and increase at a slower rate (slow increase-SI), respectively in Markov model. Besides, glacial topography was also used as an indicator of future lake size change taking a total of 457 number of lakes; thus, a total of 94, 123 and 240 lakes out of 457 were identified as lower, medium and higher prone to unconnected, respectively. Here, the common future predicted growth lakes from these two models were taken as critical lakes. The critical lakes are mostly concentrated in eastern Himalaya (227) followed by central (195) and western Himalaya (21)

Interaction of Thulium Fiber Laser with Urinary Stone: Effect of Laser Parameter on Fragmented Particle Size and Retropulsion

Single-mode thulium fiber laser (TFL) at 1.94 mu m with optimal energy and pulse settings has potential benefits for lithotripsy over the presently used Ho:YAG laser. A fiber Bragg grating-based, all-fiber, continuous-wave and modulated TFL at 1.94 mu m is configured to deliver up to 30 W of laser power with efficiency of 50%. The TFL operating in the range of repetition rate 10 Hz-1 kHz and corresponding pulse energy 2 J-1.05 mJ is irradiated on urinary stone for in-vitro evaluation of fragmented particle size and retropulsion. TFL irradiation at higher repetition rate fragments the stones into smaller particle size (average size of few hundreds microns) resulting reduced retropulsion

Measurement of total thiol, Glutathione reductase (GR), Catalase, Ascorbate Peroxidase and Superoxide dismutase (SOD) activity in different days’ nodule extracts of <i>A. hypogaea</i>.

<p>Total thiol content was measured in 20, 40 and 80 day nodule extracts as described by Akerboom and Sies, (1981). Glutathione Reductase activity was measured spectrophotometrically at 340 nm over 2 minute by following NADPH oxidation whereas Catalase and Ascorbate Peroxidase activity was measured by following the H₂O₂ oxidation spectrophotometrically at 240 nm for 2 min in 20, 40, 80 day nodule extracts of <i>A. hypogaea.</i> SOD activity was measured in the same samples using xanthine oxidase and NBT and absorption was measured at 560 nm. Results are expressed as mean ± SD, for n = 3 experiments. P≤0.01, using one-way ANOVA.</p

Representation of maintenance of Redox Cycle in nodules and bacteroid compartments.

<p>Scheme represents the nodule redox environment, and transport of redox molecules in plant cell compartment and bacteroid compartment. Based on the biochemical analysis of thiols, RSNO and redox active enzymes of plant cell and rhizobia, the exchange of molecules between the compartments has been shown. Upward arrow head indicates upregulation, downward arrowhead indicates downregulation. RSNO could be produced in the nodule compartment by several routes. Reduced glutathiones (GSH) take part in transnitrosylation reaction in nodule compartment. GSNO produced in nodule compartment may diffuse to the bacteroid cell where GSNO reductase could convert it to GSSG and NH₃; GSSG is recycled by GR and GPx. High basal level GR present in the bacteroid could recycle GSSG to GSH. GSH from the bacteroid may be transported to the nodule compartment to take part in the trans nitrosylation reaction. H₂O₂ produced in nodule compartment could be detoxified by nodule catalase, and APx and the excess H₂O₂ might be diffused to the bacteroid compartment where <i>Bradyrhizobium</i> could detoxify it with high level of catalase and GPx.</p

Quantification of thiol pool in <i>S. meliloti</i> 1021 and <i>Bradyrhizobium sp</i> after 30 minute stress with SNP in media.

<p><i>S. meliloti</i> cells were grown to mid log phase at 30°C in TY media whereas <i>Bradyrhizobium sp</i> cells were grown similarly in YEM media. Sodium nitroprusside (SNP) was added to mid log phase cell in the final concentration of 1.0 and 3.0 mM and incubated at 30°C for 30 minute. Cells were harvested, lysed and cell free crude extracts were subjected to quantification of total thiol, oxidized glutathione, reduced glutathione and ratio for reduced to oxidized glutathione. Results are expressed as mean ± SD, for n = 3 experiments. P≤0.01, using one-way ANOVA.</p

NO detection in <i>A. hypogaea</i> JL 24 and <i>M. sativa</i> nodules.

<p>All nodule sections were incubated with 10 µM DAF-2DA at 25°C for 1 hour in darkness. Photographs are representative of results obtained from the analysis of nodules in five independent experiments. Images of <i>A. hypogaea</i> nodule sections show absence of NO dependent DAF-2DA fluorescence (green colour) in (A) 20 day, (C) 40 day and (E) 80 day old nodules. (B), (D) and (F) show the corresponding bright field images. Scale bar = 200 µm. Whereas DAF-2DA dependent green colour fluorescence was observed in (G) 143 day old <i>M. sativa</i> nodule section. (H) represents the corresponding bright field image. Scale bar = 100 µm. The images of the sections were captured using excitation at 485 nm and emission at 530 nm.</p