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711.
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Induced synthesis of urease in Azotobacter vinelandii 总被引:2,自引:0,他引:2
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The regulation of nitrate assimilation in higher plants is reviewed in relation to the availability and accumulation of reduced nitrogen. The effects of light on these processes are also considered. 相似文献
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Kartik Vinodbhai Patel Jinal Hardik Naik Amaresan Natarajan 《Journal of Plant Growth Regulation》2021,40(4):1728-1740
Journal of Plant Growth Regulation - Salinity is one of the major abiotic stresses that cause retarded plant growth and crop production. It has been reported that harmful effects of salinity could... 相似文献
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Abani Kanta Naik Michael R. Lieber Sathees C. Raghavan 《The Journal of biological chemistry》2010,285(10):7587-7597
The sequence specificity of the recombination activating gene (RAG) complex during V(D)J recombination has been well studied. RAGs can also act as structure-specific nuclease; however, little is known about the mechanism of its action. Here, we show that in addition to DNA structure, sequence dictates the pattern and efficiency of RAG cleavage on altered DNA structures. Cytosine nucleotides are preferentially nicked by RAGs when present at single-stranded regions of heteroduplex DNA. Although unpaired thymine nucleotides are also nicked, the efficiency is many fold weaker. Induction of single- or double-strand breaks by RAGs depends on the position of cytosines and whether it is present on one or both of the strands. Interestingly, RAGs are unable to induce breaks when adenine or guanine nucleotides are present at single-strand regions. The nucleotide present immediately next to the bubble sequence could also affect RAG cleavage. Hence, we propose “C(d)C(S)C(S)” (d, double-stranded; s, single-stranded) as a consensus sequence for RAG-induced breaks at single-/double-strand DNA transitions. Such a consensus sequence motif is useful for explaining RAG cleavage on other types of DNA structures described in the literature. Therefore, the mechanism of RAG cleavage described here could explain facets of chromosomal rearrangements specific to lymphoid tissues leading to genomic instability. 相似文献
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Nitish Kumar K. G. Vijay Anand Muppala P. Reddy 《Journal of plant biochemistry and biotechnology.》2011,20(1):125-133
Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate. 相似文献
720.
Alkaline Phosphatase: An Appraisal of its Critical Role in C-Limited Deep-Sea Sediments of Central Indian Basin 总被引:1,自引:0,他引:1
Sushanta U. Biche Anindita Das M. B. L. Mascarenhas-Pereira B. Nagender Nath Sonali S. Naik Samita P. Helekar 《Geomicrobiology journal》2017,34(3):274-288
Alkaline phosphatase (ALP) is a hydrolase that releases phosphate, a crucial nutrient supporting formation of many macromolecules. The oligotrophic sediments of Central Indian Basin (CIB) were examined for the extent of ALP activity in 20 cores up to 20 cm depth along with other biogeochemical parameters. Northern and southern stations distinctly clustered based on pore water phosphorus (P) concentrations. ALP appeared more active in south due to more P and organic carbon (C) limitation. Central transition profiles revealed interesting mixed diagenetic and geothermal influence. Inter- and intrazonal differences suggest that broadly established paradigms applicable to water columns may deviate in space and time in sedimentary systems. Gross differences in redox status could govern differential response in ALP activity under similar hydrostatic pressure. Hydrothermal scavenging reactions striping soluble P from pore water might be widespread in CIB albeit at extreme low intensities. ALP might redissolve the precipitated P and make it reavailable to microbes. 相似文献