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41.
42.
Jagesh K. Tiwari Poonam D. Sarkar SK. Pandey Jai Gopal S. Raj Kumar 《Plant Cell, Tissue and Organ Culture》2010,103(2):175-187
Interspecific potato somatic hybrids between Solanum tuberosum L. (di)haploid C-13 and 1 endosperm balance number non-tuberous wild species S. etuberosum Lindl. were produced by protoplasts electrofusion. The objective was to transfer virus resistance from this wild species
into the cultivated potatoes. Post-fusion products were cultured in VKM medium followed by regeneration of calli in MS13 K medium at 20°C under a 16-h photoperiod, and regenerants were multiplied on MS medium. Twenty-one somatic hybrids were
confirmed by RAPD, SSR and cytoplasm (chloroplast/mitochondria) type analysis possessing species-specific diagnostic bands
of corresponding parents. Tetraploid nature of these somatic hybrids was determined through flow cytometry analysis. Somatic
hybrids showed intermediate phenotypes (plant, leaves and floral morphology) to their parents in glass-house grown plants.
All the somatic hybrids were male-fertile. ELISA assay of somatic hybrids after artificial inoculation of Potato virus Y (PVY)
infection reveals high PVY resistance. 相似文献
43.
Dalal Subhamita Adhikary Jayashree Roy Anup Biswas Shampa Sarkar Mukhopadhyay Prabir Kumar Acharya Sagar Ghosh Amlan 《Molecular biology reports》2022,49(9):8369-8380
Molecular Biology Reports - On the background of the epidemiological link between diabetes and oral cancer, the present study aimed to analyze the potential involvement of selected glucose... 相似文献
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45.
Dayanidhi Sarkar Masahiro Yabusaki Yuta Hasebe Pei Yee Ho Shuji Kohmoto Takayuki Kaga Kazuyuki Shimizu 《Applied microbiology and biotechnology》2010,87(1):127-136
The metabolism of Gluconacetobacter oboediens was investigated in relation to different carbon sources for the continuous cultures at the dilution rate of 0.05 h−1. The 13C-flux result implies the formation of metabolic recycles for the case of using glucose and acetate as carbon sources. When
glucose and ethanol were used as carbon sources, the specific ethanol uptake rate and the specific acetate production rate
increased as the feed ethanol concentration was increased from 40 to 60 g/l, while the specific CO2 production rate and the biomass concentration decreased, where the 13C-metabolic flux result indicates that the glycolysis, oxidative PP pathway, and the tricarboxylic acid (TCA) cycle were less
active, resulting in less biomass concentration. The flux result also implies that oxaloacetate decarboxylase flux became
negative, so that oxaloacetate is backed up by this pathway, resulting in less activity of glyoxylate pathway. When gluconate
was added for the case of using glucose and ethanol as carbon sources, the acetate and cell concentrations as well as gluconate
concentrations increased. The glucose and ethanol concentrations decreased concomitantly with the increased feed gluconate
concentration. In accordance with these fermentation characteristics, the enzyme activity result indicates that glucose dehydrogenase
and glucose-6-phosphate dehydrogenase pathways became less active, while the glycolysis and the TCA cycle was activated as
the feed gluconate concentration was increased. 相似文献
46.
Inflammation and glucocorticoids stimulate hepatic glycoprotein synthesis, resulting in an increased secretion of serum glycoproteins. We now present evidence that the synthesis of dolichol and dolichol phosphate from mevalonate is increased in hepatocytes from inflamed rats. Also, in inflamed rats, the levels of dolichol and dolichol phosphate are increased in liver homogenates and microsomes. Dexamethasone treatment of the cells, however, does not increase the synthesis of dolichol and dolichol phosphate from mevalonate. The results suggest that the inflammation-induced dolichol-linked saccharide and glycoprotein synthesis is possibly mediated through an increase in the level of dolichol and dolichol phosphate in the liver. Since dexamethasone treatment does not increase the synthesis of dolichol and dolichol phosphate, its action on glycoprotein synthesis appears to be different and to affect the induction of enzymes in mannosyl phosphoryl dolichol- and dolichol-linked oligosaccharide synthesis. 相似文献
47.
Putative Virulence Traits and Pathogenicity of Vibrio cholerae Non-O1, Non-O139 Isolates from Surface Waters in Kolkata, India 下载免费PDF全文
Prasanta K. Bag Poulami Bhowmik Tapas K. Hajra T. Ramamurthy Pradipta Sarkar Mrinmoyee Majumder Goutam Chowdhury Suresh C. Das 《Applied microbiology》2008,74(18):5635-5644
Vibrio cholerae non-O1, non-O139 was isolated from natural surface waters from different sites sampled in diarrhea endemic zones in Kolkata, India. Twenty-one of these isolates were randomly selected and included in the characterization. The multiserogroup isolates were compared by their virulence traits with a group of clinical non-O1, non-O139 isolates from the same geographic area. Of the 21 environmental isolates, 6 and 14 strains belonged to Heiberg groups I and II, respectively. Three of the environmental isolates showed resistance to 2,2-diamine-6,7-diisopropylpteridine phosphate. All of the non-O1, non-O139 strains were positive for toxR, and except for one environmental isolate, none of them were positive for tcpA in the PCR assay. None of the isolates were positive for genes encoding cholera toxin (ctxA), heat-stable toxin (est), heat-labile toxin (elt), and Shiga toxin variants (stx) of Escherichia coli. Additionally, except for one environmental isolate (PC32), all were positive for the gene encoding El Tor hemolysin (hly). The culture supernatants of 86% (18 of 21) of the environmental isolates showed a distinct cytotoxic effect on HeLa cells, and some of these strains also produced cell-rounding factor. The lipase, protease, and cell-associated hemagglutination activities and serum resistance properties of the environmental and clinical isolates did not differ much. However, seven environmental isolates exhibited very high hemolytic activities (80 to 100%), while none of the clinical strains belonged to this group. The environmental isolates manifested three adherence patterns, namely, carpet-like, diffuse, and aggregative adherence, and the clinical isolates showed diffuse adherence on HeLa cells. Of the 11 environmental isolates tested for enteropathogenic potential, 8 (73%) induced positive fluid accumulation (≥100) in a mouse model, and the reactivities of these isolates were comparable to those of clinical strains of non-O1, non-O139 and toxigenic O139 V. cholerae. Comparison of the counts of the colonized environmental and clinical strains in the mouse intestine showed that the organisms of both groups had similar colonizing efficiencies. These findings indicate the presence of potentially pathogenic V. cholerae non-O1, non-O139 strains in surface waters of the studied sites in Kolkata. 相似文献
48.
Two saponins, designated as bacopaside I and II, have been isolated from Bacopa monniera Wettst. and their structures have been elucidated as 3-O-alpha-L-arabinofuranosyl-(1-->2)-[6-O-sulphonyl-beta-D-glucopyranosyl-(1-->3)]-alpha-L-arabinopyranosyl pseudojujubogenin (1) and 3-O-alpha-L-arabinofuranosyl-(1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl pseudojujubogenin (2) mainly on the basis of 2D NMR and other spectral analyses. 相似文献
49.
Wilson disease is an autosomal recessive disorder of copper metabolism. The gene for this disorder has been cloned and identified to encode a copper-transporting ATPase (ATP7B), a member of a large family of cation transporters, the P-type ATPases. In addition to the core elements common to all P-type ATPases, the Wilson copper-transporting ATPase has a large cytoplasmic N-terminus comprised six heavy metal associated (HMA) domains, each of which contains the copper-binding sequence motif GMT/HCXXC. Extensive studies addressing the functional, regulatory, and structural aspects of heavy metal transport by heavy metal transporters in general, have offered great insights into copper transport by Wilson copper-transporting ATPase. The findings from these studies have been used together with homology modeling of the Wilson disease copper-transporting ATPases based on the X-ray structure of the sarcoplasmic reticulum (SR) calcium-ATPase, to present a hypothetical model of the mechanism of copper transport by copper-transporting ATPases. 相似文献
50.