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51.
Irom?Harimala?Chanu Laishram?Ronibala?Devi Nonibala?Khumanthem N.?Irabanta?Singh Dalip?Kumar Okram?Mukherjee?SinghEmail author 《Russian Journal of Bioorganic Chemistry》2017,43(2):177-185
Knoevenagel cyclocondensations of α-hydroxy naphthaldehyde with β-oxodithioesters and ketene dithioacetals yielded 2H-benzo[f]chromene-2-thiones and 2H-benzo[f]chromen-2-ones, respectively, in high yields. The newly synthesized compounds were evaluated for antifungal and antibacterial activities. Among them, compounds (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone and phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone exhibited excellent antifungal activity against tested fungi Curvularia lunata and Fusarium moniliforme. The highest antibacterial activity against the tested bacteria Escherichia coli and Staphylococcus aureus was observed for (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone. The results of antimicrobial screening demonstrate that (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone, phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone, and (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone are promising as antimicrobial drugs. 相似文献
52.
Errol?Mathias Arati?Prabhu Evans?Coutinho Sudha?SrivastavaEmail author Uma?Halkar 《International journal of peptide research and therapeutics》2005,11(2):143-152
The conformation of a cyclic analog of neuropeptide Y [Tyr1--Lys--Gly--Arg--cyclo5/8-(Glu5--Tyr--Ile--Lys8)--Leu--Ile10--Thr--Arg--Pro--Arg--Tyr15--NH2; cEK-NPY] with high Y1 receptor affinity was studied using 1H, 13C and 15N 2D-NMR and CD in three diverse media-viz. DMSO-d6, water (pH 4.0) and 50% hexafluoroacetone (HFA). The conformation of cEK-NPY was interpreted based on chemical shift (1H, 13C and 15N), temperature coefficients of the NH chemical shifts, 3JNHα coupling constants and the pattern of intra and inter-residue NOE’s and the CD spectrum. In both DMSO and water, there is a preponderance of a β-strand structure, while HFA promotes an α-helical structure, which is discontinuous in the mid-region of the peptide, due to the constraints of the lactam ring. The solution structures were generated using Restrained Molecular Dynamics simulations and further refined by Mardigras to R factors between 0.55 and 0.65. The role of its conformations in its biological activity is discussed. 相似文献
53.
Deepak?PremEmail author Subhadra?Singh Padam?Prakash?Gupta Jaivir?Singh Sish?Pal?Singh?Kadyan 《Plant Cell, Tissue and Organ Culture》2005,80(2):209-214
Guar (Cyamopsis tetragonoloba L. Taub) is a drought tolerant and multipurpose grain legume cash crop grown primarily under rainfed conditions in several countries. The effect of various growth regulators and their combinations on a variety of explants, namely the embryo, cotyledons, cotyledonary nodes, shoot tip and hypocotyle, has been studied and an efficient system for callus induction and regeneration from callus has been developed. It was established that Murashige and Skoogs culture medium containing 2,4-dichlorophenoxyacetic acid (10.0M) in combination with 6-benzylaminopurine (5.0M) with embryo or cotyledon explants is most suitable for induction of green and friable morphogenic callus, with a range of 82.5–95% of cultured explants responding to callus induction. Efficient de novo shoot regeneration was achieved by culturing the callus obtained on this medium on Murashige and Skoogs medium containing 1-naphthlenacetic acid (13.0M) in combination with 6-benzylaminopurine (5.0M) with a range of 82.1–88.4% of callus clumps producing 20–25 shoots. In vitro rooting of cultured shoots was obtained on half-salt concentration of Murashige and Skoogs culture medium supplied with indole-3-butyric acid (5.0M) on which 82–90% of cultured shoots produced healthy roots. The in vitro regenerated plants were grown to pod setting and subsequent maturity under greenhouse conditions. 相似文献
54.
Quinn CF Prins CN Freeman JL Gross AM Hantzis LJ Reynolds RJ Yang S Covey PA Bañuelos GS Pickering IJ Fakra SC Marcus MA Arathi HS Pilon-Smits EA 《The New phytologist》2011,192(3):727-737
? Selenium (Se) hyperaccumulation has a profound effect on plant-arthropod interactions. Here, we investigated floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant-pollinator interactions. ? Floral Se distribution and speciation were compared in Stanleya pinnata, an Se hyperaccumulator, and Brassica juncea, a comparable nonhyperaccumulator. Pollen germination was measured from plants grown with varying concentrations of Se and floral visitation was compared between plants with high and low Se. ? Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-selenocysteine (MeSeCys). Brassica juncea had higher Se concentrations in leaves than flowers, and a lower fraction of MeSeCys. For B. juncea, high floral Se concentration impaired pollen germination; in S. pinnata Se had no effect on pollen germination. Floral visitors collected from Se-rich S. pinnata contained up to 270 μg g(-1), concentrations toxic to many herbivores. Indeed, floral visitors showed no visitation preference between high- and low-Se plants. Honey from seleniferous areas contained 0.4-1 μg Se g(-1), concentrations that could provide human health benefits. ? This study is the first to shed light on the possible evolutionary cost, through decreased pollen germination in B. juncea, of Se accumulation and has implications for the management of seleniferous areas. 相似文献
55.
Ozaltin F Ibsirlioglu T Taskiran EZ Baydar DE Kaymaz F Buyukcelik M Kilic BD Balat A Iatropoulos P Asan E Akarsu NA Schaefer F Yilmaz E Bakkaloglu A;PodoNet Consortium 《American journal of human genetics》2011,(1):139-147
Idiopathic nephrotic syndrome (INS) is a genetically heterogeneous group of disorders characterized by proteinuria, hypoalbuminemia, and edema. Because it typically results in end-stage kidney disease, the steroid-resistant subtype (SRNS) of INS is especially important when it occurs in children. The present study included 29 affected and 22 normal individuals from 17 SRNS families; genome-wide analysis was performed with Affymetrix 250K SNP arrays followed by homozygosity mapping. A large homozygous stretch on chromosomal region 12p12 was identified in one consanguineous family with two affected siblings. Direct sequencing of protein tyrosine phosphatase receptor type O (PTPRO; also known as glomerular epithelial protein-1 [GLEPP1]) showed homozygous c.2627+1G>T donor splice-site mutation. This mutation causes skipping of the evolutionarily conserved exon 16 (p.Glu854_Trp876del) at the RNA level. Immunohistochemistry with GLEPP1 antibody showed a similar staining pattern in the podocytes of the diseased and control kidney tissues. We used a highly polymorphic intragenic DNA marker-D12S1303-to search for homozygosity in 120 Turkish and 13 non-Turkish individuals in the PodoNet registry. This analysis yielded 17 candidate families, and a distinct homozygous c.2745+1G>A donor splice-site mutation in PTPRO was further identified via DNA sequencing in a second Turkish family. This mutation causes skipping of exon 19, and this introduces a premature stop codon at the very beginning of exon 20 (p.Asn888Lysfs*3) and causes degradation of mRNA via nonsense-mediated decay. Immunohistochemical analysis showed complete absence of immunoreactive PTPRO. Ultrastructural alterations, such as diffuse foot process fusion and extensive microvillus transformation of podocytes, were observed via electron microscopy in both families. The present study introduces mutations in PTPRO as another cause of autosomal-recessive nephrotic syndrome. 相似文献
56.
鲤鱼肥胖基因的分子克隆及在大肠杆菌中的表达 总被引:2,自引:0,他引:2
为了研究鲤鱼肥胖基因的结构特点和体外表达产物的生物学活性 ,利用RT PCR技术从鲤鱼肠系膜脂肪组织中扩增出鲤鱼肥胖基因的cDNA编码序列 ,分析表明该cDNA序列由 4 38个核苷酸组成 ,编码 14 6个氨基酸组成的多肽 ,鲤鱼肥胖基因与人、猪、鼠的相比 ,核苷酸同源性分别为 :84 %、 86 %、 95 % ;氨基酸的同源性分别为 84 %、 82 %、 96 %。构建了原核表达载体 pET 2 8a li,利用IPTG在大肠杆菌中进行了诱导表达 ,并对表达产物进行了初步纯化和生物活性检测 ,结果表明 ,鲤鱼肥胖基因在大肠杆菌中进行了高效特异性融合表达 ,融合蛋白质分子量约为 2 0kD ,经薄层扫描分析 ,目的蛋白占菌体总蛋白的 2 0 3%。表达产物经过纯化和复性能够明显抑制小鼠的摄食和生长 ,说明表达产物Leptin具有明显的生物学活性 相似文献
57.
58.
59.
Hosakatte?Niranjana?MurthyEmail author Vijayalaxmi?S.?Dandin Kee-Yoeup?PaekEmail author 《Phytochemistry Reviews》2016,15(1):129-145
Adventitious roots are natural roots which develop from the differentiated cells of any organ such as leaf, root or stem. These roots are attractive source of phytochemicals due to their genetic and biosynthetic stability. Their stability offers new scope for the in vitro production of valuable secondary metabolites. In the past two decades, adventitious roots have been induced from different plant systems and the suspension cultures have been established. However, the special morphology of adventitious roots hampers the scale-up processes, which needs modifications with the existing bioreactors to facilitate proper mixing, aeration and which can overcome shear stress. Various modifications have been done with the stirred tank and air-lift bioreactors and successfully used for the cultivation of adventitious roots. The progress made in this area is tremendous, in few cases adventitious root cultures are succeeded up to commercial scale with step-wise viz. small scale to large-scale by establishing the standards with various parameters which affect the biomass accumulation and metabolite productivity. This review addresses the recent progresses made in this area and discusses the potential applications and limitations. 相似文献
60.
Kousik?Chandra Venkatesh?Ramakrishnan Yogendra?Sharma K.?V.?R.?CharyEmail author 《Journal of biological inorganic chemistry》2011,16(1):81-95
Neuronal calcium sensor-1 (NCS-1) interacts with many membranes and cytosolic proteins, both in a Ca2+-dependent and in a Ca2+-independent manner, and its physiological role is governed by its N-terminal myristoylation. To understand the role of myristoylation
in altering Ca2+ response and other basic biophysical properties, we have characterized the Ca2+ filling pathways in both myristoylated (myr) and non-myristoylated (non-myr) forms of NCS-1. We have observed that Ca2+ binds simultaneously to all three active EF-hands in non-myr NCS-1, whereas in the case of myr NCS-1, the process is sequential,
where the second EF-hand is filled first, followed by the third and fourth EF-hands. In the case of myr NCS-1, the observed
sequential Ca2+ binding process becomes more prominent in the presence of Mg2+. Besides, the analysis of 15N-relaxation data reveals that non-myr NCS-1 is more dynamic than myr NCS-1. The overall molecular tumbling correlation time
increases by approximately 20% upon myristoylation. Comparing the apo forms of non-myr NCS-1 and myr NCS-1, we found the possibility
of existence of some substates, which are structurally closer to the holo form of the protein. There are more such substates
in the case of non-myr NCS-1 than in the case of the myr NCS-1, suggesting that the former accesses larger volumes of conformational
substates compared with the latter. Further, the study reveals that the possibility of Ca2+ binding simultaneously to different parts of the protein is more favourable in non-myr NCS-1 than in myr NCS-1. 相似文献