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71.
Niranjan Mishra Katherukamem Rajukumar Shruti Shrikant Pitale Anil Prakash Ram Kumar Nema Sthita Pragnya Behera Shiv Chandra Dubey 《Journal of biosciences》2010,35(1):79-86
Bovine viral diarrhoea virus (BVDV) is an economically important pathogen of cattle and sheep belonging to the genus Pestivirus of the family Flaviviridae. Although the BVDV non-structural N-terminal protease (Npro) acts as an interferon antagonist and subverts the host innate immunity, little is known about its immunogenicity. Hence,
we expressed a recombinant BVDV Npro-His fusion protein (28 kDa) in E. coli and determined the humoral immune response generated by it in rabbits. The antigenicity of the Npro protein was confirmed by western blot using anti-BVDV hyperimmune cattle, sheep and goat serum, and anti-Npro rabbit serum. When rabbits were immunized with the Npro protein, a humoral immune response was evident by 4 weeks and persisted till 10 weeks post immunization as detected by ELISA
and western blot. Despite Npro-specific antibodies remaining undetectable in 80 serum samples from BVDV-infected sheep and goats, BVDV hyperimmune sera
along with some of the field cattle, sheep and goat sera with high BVDV neutralizing antibody titres were found positive for
Npro antibodies. Our results provide evidence that despite the low immunogenicity of the BVDV Npro protein, a humoral immune response is induced in cattle, sheep and goats only with repeated BVDV exposure. 相似文献
72.
The site specific mutants of the thermophilic P450 (P450 175A1 or CYP175A1) were designed to introduce residues that could act as acid-base catalysts near the active site to enhance the peroxidases activity. The Leu80 in the distal heme pocket of CYP175A1 was located at a position almost equivalent to the Glu183 that is involved in stabilization of the ferryl heme intermediate in chloroperoxidase (CPO). The Leu80 residue of CYP175A1 was mutated with histidine (L80H) and glutamine (L80Q) that could potentially form hydrogen bond with hydrogen peroxide and facilitate formation and stabilization of the putative redox intermediate of the peroxidase cycle. The mutants L80H and L80Q of CYP175A1 showed higher peroxidase activity compared to that of the wild type (WT) CYP175A1 enzyme at 25 °C. The activity constants (kcat) for the L80H and L80Q mutants of CYP175A1 were higher than those of myoglobin and wild type cytochrome b562 at 25 °C. The optimum temperature for the peroxidase activity of the WT and mutants of CYP175A1 was ~ 70 °C. The rate of catalysis at temperatures above ~ 70 °C was higher for L80Q mutant of CYP175A1 compared to that of the well known natural peroxidase, horseradish peroxidase (HRP) that denatures at such high temperature. The peroxidase activities of the mutants of CYP175A1 were maximum at pH 9, unlike that of HRP which is at pH ~ 5. The results have been discussed in the light of understanding the structure-function relationship of the peroxidase properties of these thermostable heme proteins. 相似文献
73.
Floral composition and structural parameters of the herbaceous vegetation of four recovering tropical dry deciduous forest
stands protected for 2, 4, 6 and 10-year periods, on the Eastern Ghats of India, situated at Kandhamal district of Orissa,
India were investigated. More than 1 ha of recovering forest stands of each of the four stages was selected and fifteen sample
quadrats of 1 m × 1 m were randomly placed at each stand for vegetation analysis. Floristic analysis revealed highest number
of species (69) in 2-year recovering stand, which declined with increase in age. A total of 87 species, 71 genera and 32 families
were recorded in the forest stands. Total number of herbaceous species encountered in the stands was 44, 28, 30 and 24 in
2, 4, 6 and 10-year stands, respectively. Total individuals of all herb species were 114, 70, 88 and 68 plant m−2 in 2, 4, 6 and 10-year stands, respectively. Herbaceous stand basal areas were 7.84, 3.66, 4.77 and 5.23 cm2 m−2 in 2, 4, 6, and 10-year stands, respectively. Importance value index (IVI) revealed that Heteropogon contortus was predominant in 2 and 4-year stands, Andrographis paniculatus in 6-year stand and Elephantopus scaber in 10-year stand. Diversity-dominance curve revealed lognormal distribution in all the four stands. Simpson’s dominance index
(C) was highest in 2-year stand which decreased in other stands, while Shannon’s diversity index (H1) was almost the same in all the stands. Biomass of herbaceous vegetation was 83.2 g m−2 in 2 year, 62.2 g m−2 in 4 year, 58.0 g m−2 in 6 year and 64.0 g m−2 in 10-year stand. 相似文献
74.
Mandal EK Maity K Maity S Gantait SK Behera B Maiti TK Sikdar SR Islam SS 《Carbohydrate research》2012,347(1):172-177
An immunostimulating water-soluble glucan was isolated from hot aqueous extract of fruit bodies of an edible mushroom Calocybe indica. Structural investigation of the glucan was carried out using acid hydrolysis, methylation analysis, and NMR studies ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as [see figure in text]. This glucan stimulated the splenocytes and thymocytes. 相似文献
75.
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77.
S. A. Nayak S. Kumar K. Satapathy A. Moharana B. Behera D. P. Barik L. Acharya P. K. Mohapatra P. K. Jena S. K. Naik 《Acta Physiologiae Plantarum》2013,35(1):195-203
An efficient large-scale clonal propagation protocol has been described for Withania somnifera (L.) Dunal, a valuable medicinal plant, using cotyledonary nodes derived from axenic seedlings. Murashige and Skoog’s (Physiol Plant 15:473–497, 1962) (MS) medium supplemented with 1.0 mg l?1 N 6-benzyladenine (BA) was found to be optimum for production of multiple shoots (100 % shoot proliferation frequency and 16.93 shoots per explant). Successive shoot cultures were established by repeatedly sub-culturing the original cotyledonary node on a fresh medium after each harvest of newly formed shoots. Multiple shoot proliferation was also achieved from nodal segments derived from in vitro raised shoots on MS medium augmented with 1.0 mg l?1 BA. Regenerated shoots were best rooted (95.2 %, 38.7 roots per shoot) in half-strength MS medium supplemented with 1.0 mg l?1 indole-3-butyric acid. The plantlets were successfully acclimated and established in soil. Random amplified polymorphic DNA and inter-simple sequence repeats analysis revealed a homogeneous amplification profile for all micropropagated plants analyzed validating the genetic fidelity of the in vitro regenerated plants. 相似文献
78.
Yukiko Sasaki‐Yamamoto Tomonari Akamatsu Tamaki Ura Harumi Sugimatsu Junichi Kojima Rajendar Bahl Sandeep Behera Shiro Kohshima 《Marine Mammal Science》2013,29(4):589-605
We monitored the underwater movements of Ganges River dolphins using stationed stereo acoustic data loggers. We estimated these movements using changes in the relative angle of the sound source direction (trajectory). Of the total acoustic recordings (66 h), 26.2% contained trajectories of dolphins, and 78.6% of these trajectories involved single animals, suggesting that dolphins tended to swim alone and were localized near the monitoring station. The observed trajectories were categorized as follows: staying type characterized by small changes in the sound source direction, moving type A (moving in the same direction), and moving type B (moving up and down the stream during recording). The average interpulse intervals of sounds in moving types A and B were significantly shorter than that of the staying type, suggesting that dolphins produce the former types of trajectories to echolocate across shorter distances during movement. The frequency of occurrence of moving type A increased during the night, whereas that of type B increased in the late afternoon and that of the staying type increased during the daytime. These results indicate that dolphins moving at night tended to use short‐range echolocation, whereas during the day, they remained in relatively small areas and used long‐range sonar. 相似文献
79.
Srivastava V Vashishta M Gupta S Singla R Singla N Behera D Natarajan K 《Immunology and cell biology》2011,89(7):786-791
Protective immune responses during Mycobacterium tuberculosis (M. tuberculosis) infection are regulated at multiple levels and critically dependent on the balance in the secretion of pro-inflammatory and regulatory cytokines. A key factor that governs this balance at the cellular level is suppressors of cytokine signaling (SOCS). We recently demonstrated that toll-like receptor 2 and dendritic cell (DC)-SIGNR1 differentially regulate SOCS1 expression in DCs during M. tuberculosis infection. This consecutively regulated IL-12 production and determined M. tuberculosis survival. In this study, we characterized the role of SOCS1 in regulating effector responses from CD4(+) and CD8(+) T cells during M. tuberculosis infection. Our data indicate that T cells from M. tuberculosis-infected mice show increased and differential association of SOCS1 with CD3 and CD28, when compared with uninfected mice. While SOCS1 displays increased association with CD3 than CD28 in CD4(+) T cells; SOCS1 is associated more with CD28 than CD3 in CD8(+) T cells. Further, SOCS1 shows increased association with IL-12 and IL-2 receptors in both CD4(+) and CD8(+) T cells from infected mice when compared with naive mice. Silencing SOCS1 in T cells increased signal transduction from T cell receptor (TCR) and CD28 with enhanced activation of key signaling molecules and proliferation. Significantly, SOCS1-silenced T cells mediated enhanced clearance of M. tuberculosis inside macrophages. Finally, adoptive transfer of SOCS1-silenced T cells in M. tuberculosis-infected mice mediated significant reduction in M. tuberculosis loads in spleen. These results exemplify the negative role played by SOCS1 during T cell priming and effector functions during M. tuberculosis infection. 相似文献
80.
Pradhan Biswajita Patra Srimanta Behera Chhandashree Nayak Rabindra Patil Shankargouda Bhutia Sujit K. Jena Mrutyunjay 《Molecular biology reports》2020,47(12):9567-9578
Molecular Biology Reports - Marine algae are an auspicious source of innovative bioactive compounds containing possible therapeutic agents against mammalian cancers. However, the mechanism by which... 相似文献