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151.
The biological activities of a sterile red fungus (SRF) capable of plant growth promotion and suppression of take-all disease
were investigated in soils collected from Lancelin, Newdegate and Mt. Barker regions of Western Australia. Further, the effects
of three wheat cultivars and the presence of two isolates ofStreptomyces on the biological activities of the SRF were tested using the Lancelin soil. The biological activities of the SRF were greatest
in the Lancelin and Newdegate (wheat field) soils and with the wheat cultivar Gutha. In in vitro studies the soil streptomycetes
tested showed either a significant increase in the exudate production by the SRF, which had antifungal and growth promoting
properties, or an inhibition of growth of the fungus. Streptomycete A63 which stimulated the exudate production by the SRF
in vitro, however, did not enhance disease protection in vivo. On the other hand, protection from root rot by the SRF in vivo
was reduced in the presence of the streptomycete isolate Ax which is capable of inhibiting the growth of the SRF in vitro. 相似文献
152.
153.
Gejjalagere S. Lingaraju Kyathegowdanadoddi S. Balaji Shankar Jayarama Seegehalli M. Anil Kuppalli R. Kiran Maralinganadoddi P. Sadashiva 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3606-3612
A series of new coumarin tethered isoxazolines (7a-l) were synthesized and evaluated for their cytotoxic potency against human melanoma cancer cell line (UACC 903) as well as fibroblast normal cell line (FF2441). Preliminary results revealed that some of these coumarin tethered isoxazolines 7b, 7c, 7f and 7j exhibited significant antiproliferative effect against human melanoma cancer (UACC 903) with IC50 values of 8.8, 10.5, 9.2 and 4.5?μM respectively. However, compound 7c was non-toxic to normal human cells at the tested concentration. Further, we have chosen compound 7c to check its efficacy in Ehrlich Ascites Carcinoma animal model in-vivo for its antitumor and antiangiogenic properties. Our lead compound significantly reduced the cell viability, body weight, ascites volume and downregulated the formation of neovasculature such as regression of tumor volume. The present study indicates the scope of developing into potent anticancer drug in near future. 相似文献
154.
Basavegowdanadoddi Marinaik Chandranaik Sonnahallipura Munivenkatappa Byregowda Mudalagiri Dasappagupta Venkatesha Kantharajapura Ramanna Ramesha Poojappa Nandini Poorvi Reddy Thushara Bindu KV Beechagondahalli Papanna Shivashankar Byadarahalli Puttaswamy Shankar Methuku Sobha Rani 《European Journal of Wildlife Research》2018,64(1):4
We report the molecular epidemiology of highly pathogenic avian influenza (HPAI) virus involved in an outbreak causing death in free-ranging wild birds at Mysore, Karnataka state of India. The virus was typed as HPAI A(H5N8) by conventional and TaqMan probe based real-time PCR assays. Six isolates of HPAI virus were recovered in 9-day-old embryonated chicken eggs. Haemagglutinin gene-based phylogeny of virus isolates showed >?99.9% nucleotide sequence identity with HPAI A(H5N8) isolates from migratory birds and domestic poultry from China and Korea indicating either these wild birds have routed their migration through Korea and/or eastern China or these dead birds must have directly or indirectly contacted with wild birds migrating from Eastern China and/or Korean regions. The study emphasises the role of migratory wild birds in spread of HPAI across the globe. 相似文献
155.
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157.
NMR reveals the absence of hydrogen bonding in adjacent UU and AG mismatches in an isolated internal loop from ribosomal RNA 总被引:2,自引:0,他引:2
NMR studies provide insights into structural features of internal loops. These insights can be combined with thermodynamic studies to generate models for predicting structure and energetics. The tandem mismatch internal loop, 5'GUGG3'(3'CUAC5'), has been studied by NMR. The NMR structure reveals an internal loop with no hydrogen bonding between the loop bases and with the G in the AG mismatch flipped out of the helix. The sequence of this internal loop is highly conserved in rRNA. The loop is located in the large ribosomal subunit and is part of a conserved 58-nt fragment that is the binding domain of ribosomal protein L11. Structural comparisons between variants of this internal loop in crystal structures of the 58-nt domain complexed with L11 protein and of the large ribosomal subunit (LSU) suggest that this thermodynamically destabilizing internal loop is partially preorganized for tertiary interactions and for binding L11. A model for predicting the base pairing and free energy of 2 x 2 nucleotide internal loops with a purine-purine mismatch next to a pyrimidine-pyrimidine mismatch is proposed on the basis of the present NMR structure and previously reported thermodynamics. 相似文献
158.
Chemical modification studies on purified RNase Rs revealed the involvement of a single histidine, lysine and carboxylate residue in the catalytic activity of the enzyme. RNA could not protect the enzyme against DEP- and TNBS-mediated inactivation whereas, substrate protection was observed in case of EDAC-mediated inactivation of the enzyme. K(m) and k(cat) values of the partially inactivated enzyme samples suggested that while histidine and lysine are involved in catalysis, carboxylate is involved in substrate binding. Active site nature of RNase Rs suggests that the inability of the enzyme to readily convert 2',3'-cyclic nucleotides to 3'-mononucleotides is probably due to the absence of catalytically active second histidine residue. 相似文献
159.
Gayoor Ali A. Arif Ibrahim Prem Shankar Srivastava Muhammad Iqbal 《Journal of Plant Biology》1999,42(3):222-225
Various concentrations of salt (NaCI) were shown to have an influence on the differentiation of tissues in the root and stem
ofBacopa monniera (L) Wettst. Higher concentrations induced drastic changes in roots grown on salt-supplemented media; epidermal and cortical
cells experienced changes in shape, size, and orientation and/or were got disintegrated. A low concentration of salt induced
a profuse development of root hairs which gradually disappeared at higher concentrations. Air spaces in the stem cortex were
enlarged and xylem cell walls in the vascular ring were thickened. 相似文献