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271.
B. stearothermophilus strain AG-49, when cultivated in mineral medium in the presence of silica (SA), adhered to SA. Adhesion depended on age of
culture, contact time and glucose concentration of the culture medium. Mid-exponential phase culture (5 h) required minimum
contact time (30 min) for maximum adhesion. 0.6% glucose concentration was optimum. Quantitative variation in protein and
saccharide extractable in sodium chloride and sodium dodecyl sulfate (SDS) was observed. Five % degradation of fenitrothion
by adherentB. stearothermophilus could be achieved in 4 d. 相似文献
272.
Ikuko Kakizaki Keiichi Takagaki Yasufumi Endo Daisuke Kudo Hitoshi Ikeya Teruzo Miyoshi Bruce A Baggenstoss Valarie L Tlapak-Simmons Kshama Kumari Akio Nakane Paul H Weigel Masahiko Endo 《European journal of biochemistry》2002,269(20):5066-5075
As observed previously in cultured human skin fibroblasts, a decrease of hyaluronan production was also observed in group C Streptococcus equi FM100 cells treated with 4-methylumbelliferone (MU), although there was no effect on their growth. In this study, the inhibition mechanism of hyaluronan synthesis by MU was examined using Streptococcus equi FM100, as a model. When MU was added to a reaction mixture containing the two sugar nucleotide donors and a membrane-rich fraction as an enzyme source in a cell-free hyaluronan synthesis experiment, there was no change in the production of hyaluronan. On the contrary, when MU was added to the culture medium of FM100 cells, hyaluronan production in the isolated membranes was decreased in a dose-dependent manner. However, when the effect of MU on the expression level of hyaluronan synthase was examined, MU did not decrease either the mRNA level of the has operon containing the hyaluronan synthase gene or the protein level of hyaluronan synthase. Solubilization of the enzyme from membranes of MU-treated cells and addition of the exogenous phospholipid, cardiolipin, rescued hyaluronan synthase activity. In the mass spectrometric analysis of the membrane phospholipids from FM100 cells treated with MU, changes were observed in the distribution of only cardiolipin species but not of the other major phospholipid, PtdGro. These results suggest that MU treatment may cause a decrease in hyaluronan synthase activity by altering the lipid environment of membranes, especially the distribution of different cardiolipin species, surrounding hyaluronan synthase. 相似文献
273.
Avni Mann Juhi Kumari Roshan Kumar Pawan Kumar Akshay K. Pradhan Deepak Pental Naveen C. Bisht 《Plant biotechnology journal》2023,21(11):2182-2195
Glucosinolate content in the two major oilseed Brassica crops—rapeseed and mustard has been reduced to the globally accepted Canola quality level (<30 μmoles/g of seed dry weight, DW), making the protein-rich seed meal useful as animal feed. However, the overall lower glucosinolate content in seeds as well as in the other parts of such plants renders them vulnerable to biotic challenges. We report CRISPR/Cas9-based editing of glucosinolate transporter (GTR) family genes in mustard (Brassica juncea) to develop ideal lines with the desired low seed glucosinolate content (SGC) while maintaining high glucosinolate levels in the other plant parts for uncompromised plant defence. Use of three gRNAs provided highly efficient and precise editing of four BjuGTR1 and six BjuGTR2 homologues leading to a reduction of SGC from 146.09 μmoles/g DW to as low as 6.21 μmoles/g DW. Detailed analysis of the GTR-edited lines showed higher accumulation and distributional changes of glucosinolates in the foliar parts. However, the changes did not affect the plant defence and yield parameters. When tested against the pathogen Sclerotinia sclerotiorum and generalist pest Spodoptera litura, the GTR-edited lines displayed a defence response at par or better than that of the wild-type line. The GTR-edited lines were equivalent to the wild-type line for various seed yield and seed quality traits. Our results demonstrate that simultaneous editing of multiple GTR1 and GTR2 homologues in mustard can provide the desired low-seed, high-leaf glucosinolate lines with an uncompromised defence and yield. 相似文献
274.
Neha Kumari Tripurari Kumar Harsh Arnab S. Bhattacharya Kumar Gaurav Ranjana Verma Sanjoy K. Samdarshi 《Luminescence》2023,38(7):1282-1286
Transition metal oxide has emerged as one of the most potential candidates for environment remediation by utilizing solar energy through photocatalysis. This study compares the optical characteristics of zinc oxide (ZnO) and ceria-doped zinc oxide (CeZnO) nanoparticles synthesized through a facile chemical precipitation method without using any assistant catalyst. The present work investigates the consequences of ceria (cerium dioxide, CeO2) intrusion on the photocatalytic activity of ZnO nanoparticles using methylene blue (MB) as a probe pollutant. The CeZnO showed an increase in photoactivity when compared to ZnO nanoparticles for degradation of MB in an aqueous solution under ultraviolet (UV) irradiance. The resulting heterojunction between ZnO and that of ceria enhances the charge separation efficiency showing a strong correlation between ZnO and CeO2 heterojunction on the charge transfer mechanism across the interface. 相似文献
275.
Ganesh Harini S. Shree Ganesh Ramprasad Anushikaa Ramanathan Bharathi Sankaranarayanan Aravind Kumari Vatsala Abinaya Shanmugavadivu Nagarajan Selvamurugan 《化学与生物多样性》2023,20(6):e202201006
Veratric acid (VA) is plant-derived phenolic acid known for its therapeutic potential, but its anticancer effect on highly invasive triple-negative breast cancer (TNBC) is yet to be evaluated. Polydopamine nanoparticles (nPDAs) were chosen as the drug carrier to overcome VA's hydrophobic nature and ensure a sustained release of VA. We prepared pH-sensitive nano-formulations of VA-loaded nPDAs and subjected them to physicochemical characterization and in vitro drug release studies, followed by cell viability and apoptotic assays on TNBC cells (MDA-MB-231 cells). The SEM and zeta analysis revealed spherical nPDAs were uniform size distribution and good colloidal stability. In vitro drug release from VA-nPDAs was sustained, prolonged and pH-sensitive, which could benefit tumor cell targeting. MTT and cell viability assays showed that VA-nPDAs (IC50=17.6 μM) are more antiproliferative towards MDA-MB-231 cells than free VA (IC50=437.89 μM). The induction of early and late apoptosis by VA-nPDAs in the cancer cells was identified using annexin V and dead cell assay. Thus, the pH response and sustained release of VA from nPDAs showed the potential to enter the cell, inhibit cell proliferation, and induce apoptosis in human breast cancer cells, indicating the anticancer potential of VA. 相似文献
276.
The regeneration of Saccharomyces cerevisiae, NCIM 3288, cells from its sphaeroplasts were found to be influenced by a number of factors. The most suitable conditions of regeneration were also dependent on growth medium, that is, using malt-extractglucose-yeast extract-peptone (MGYP) medium: mannitol 0.7 M, pH 6.5, 30 °C and using yeast extract-peptone-glucose (YPG) medium: sucrose 0.7 M, pH 5.0 and 30 °C. The maximum regeneration frequency was observed in YPG medium. 相似文献
277.
278.
S H Gregory H L Kumari M V Lakshmi S K Bose 《Archives of biochemistry and biophysics》1976,175(2):644-653
The effects of transformation by murine sarcoma virus and of increasing cell density on the activities of several key glycolytic enzymes in Balb 3T3 cells were tested. Hexokinase levels increased with culture density in the uninfected and in the two virus-transformed (HB2 and KA31) cells. Phosphofructokinase did not increase with culture density in the uninfected cells but rose dramatically in dense cultures of virus-transformed cells. 6-Phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase levels were high in sparse cultures of uninfected cells and decreased steadily with increased culture density. Pyruvate kinase levels increased with density only in KA31 cultures. A density-dependent decrease in the level of hexokinase type II with a concomitant increase in type I isozyme was seen in uninfected 3T3 cultures. This change was negligible in HB2 cells. 相似文献
279.
Degradation of Alpha-, Beta-, and Gamma-Hexachlorocyclohexane by a Soil Bacterium under Aerobic Conditions 总被引:6,自引:1,他引:5 下载免费PDF全文
Siddhartha K. Sahu Kamala Kumari Patnaik Manikonda Sharmila N. Sethunathan 《Applied microbiology》1990,56(11):3620-3622
A Pseudomonas sp., isolated from sugarcane rhizosphere soil, readily metabolized not only alpha and gamma isomers of hexachlorocyclohexane, but also the thermodynamically more stable beta isomer, under aerobic conditions. Bacterial degradation of the three isomers led to the accumulation of a transitory metabolite and eventual release of covalently linked chlorine as chloride in stoichiometric amounts. 相似文献
280.
Sunita Sharma Sibaji K. Sanyal Kumari Sushmita Manisha Chauhan Amit Sharma Gireesh Anirudhan Sindhu K. Veetil Suneel Kateriya 《Current Genomics》2021,22(3):181
Changes in environmental conditions like temperature and light critically influence crop production. To deal with these changes, plants possess various photoreceptors such as Phototropin (PHOT), Phytochrome (PHY), Cryptochrome (CRY), and UVR8 that work synergistically as sensor and stress sensing receptors to different external cues. PHOTs are capable of regulating several functions like growth and development, chloroplast relocation, thermomorphogenesis, metabolite accumulation, stomatal opening, and phototropism in plants. PHOT plays a pivotal role in overcoming the damage caused by excess light and other environmental stresses (heat, cold, and salinity) and biotic stress. The crosstalk between photoreceptors and phytohormones contributes to plant growth, seed germination, photo-protection, flowering, phototropism, and stomatal opening.Molecular genetic studies using gene targeting and synthetic biology approaches have revealed the potential role of different photoreceptor genes in the manipulation of various beneficial agronomic traits. Overexpression of PHOT2 in Fragaria ananassa leads to the increase in anthocyanin content in its leaves and fruits. Artificial illumination with blue light alone and in combination with red light influence the growth, yield, and secondary metabolite production in many plants, while in algal species, it affects growth, chlorophyll content, lipid production and also increases its bioremediation efficiency. Artificial illumination alters the morphological, developmental, and physiological characteristics of agronomic crops and algal species. This review focuses on PHOT modulated signalosome and artificial illumination-based photo-biotechnological approaches for the development of climate-smart crops. 相似文献