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101.
A protocol for plant regeneration from mesophyll and callus protoplasts of Robinia pseudoacacia L. was developed. For leaves from in vitro raised shoots, an enzyme combination of 2.0% cellulose and 0.3% macerozyme for
a digestion period of 20 h resulted in the best yield of protoplasts (9.45 × 105 protoplast/g fresh weight). Mesophyll-derived protoplasts started cell wall regeneration within 24 h of being embedded in
Nagata and Takebe (NT) medium supplemented with 5 μM NAA and 1 μM BAP followed by the first cell division on day three of
culture and micro-colony (32 cells) formation within day 7–10 in the same medium. However, using callus as the starting material,
a combination of 2.0% cellulose and 1.0% macerozyme for a digestion period of 24 h gave the highest protoplast yield (3.2 × 105 protoplast/g fresh weight). Cell wall regeneration in callus-derived protoplasts started within 24 h followed by the first
cell division on the day three (96 h) and the appearance of microcolonies of more than 32 cells by the end of first week (144 h)
of culture on solid WPM medium supplemented with 5 μM NAA and 1 μM BAP. Microcalli were visible to the naked eye after 45 days
on solid WPM medium. Proliferation of macro-calli was successfully accomplished on solid Murashige and Skoog (MS) medium with
5 μM NAA and 5 μM BAP. Both mesophyll and callus protoplast-derived calli produced shoots on MS medium with 0.5 μM NAA and
1 μM BAP within 25–30 days and multiplied on MS medium with 1.25 μM BAP. Excised microshoots were dipped in 1–2 ml of 2.0 μM
IBA for 24 h under dark aseptic conditions and transferred to double sterilized sand for rooting. The flasks containing sand
were inoculated with Rhizobium for in vitro nodulation. Forty-five plants transferred to pots in the glasshouse established well. 相似文献
102.
Deepika Dayal Mathur Sachin Deshmukh Himani Kaushik Lalit C. Garg 《Applied microbiology and biotechnology》2010,88(4):877-884
Clostridium perfringens types B and D are responsible for enterotoxaemia, one of the major causes of cattle mortality and is therefore of great economic
concern. The epsilon toxin produced by the organism is the major antigenic determinant and has been directly implicated for
the disease causation. In the present paper, we evaluated the biological activity of the recombinant epsilon toxin (rEtx)
produced as soluble protein in Escherichia coli. The rEtx was purified to near homogeneity by a one-step anion-exchange chromatography. The immunological identity of purified
rEtx was confirmed by Western blotting using a monoclonal antibody against the native toxin. The rEtx formed heptamer in the
Madin–Darby canine kidney (MDCK) cells and synaptosomal membrane of mouse brain and was cytotoxic to the MDCK cells with a
CT50 of 30 ng/ml. The rEtx was highly stable and its thermostability profile related well with its biological activity. The rEtx
was purified in large amounts and exhibited all the properties of native toxin and therefore can be used for the development
of vaccine against the pathogen. 相似文献
103.
Shaolin Wang Eric Peatman Jason Abernathy Geoff Waldbieser Erika Lindquist Paul Richardson Susan Lucas Mei Wang Ping Li Jyothi Thimmapuram Lei Liu Deepika Vullaganti Huseyin Kucuktas Christopher Murdock Brian C Small Melanie Wilson Hong Liu Yanliang Jiang Yoona Lee Fei Chen Jianguo Lu Wenqi Wang Peng Xu Benjaporn Somridhivej Puttharat Baoprasertkul Jonas Quilang Zhenxia Sha Baolong Bao Yaping Wang Qun Wang Tomokazu Takano Samiran Nandi Shikai Liu Lilian Wong Ludmilla Kaltenboeck Sylvie Quiniou Eva Bengten Norman Miller John Trant Daniel Rokhsar Zhanjiang Liu 《Genome biology》2010,11(1):1-14
104.
Katie J. Porter Babu Gonipeta Sitaram Parvataneni Daniel M. Appledorn Sonika Patial Deepika Sharma Venugopal Gangur Andrea Amalfitano Narayanan Parameswaran 《Journal of cellular physiology》2010,225(2):406-416
β‐Arrestins are scaffolding proteins implicated as negative regulators of TLR4 signaling in macrophages and fibroblasts. Unexpectedly, we found that β‐arrestin‐1 (β‐arr‐1) and ‐2 knockout (KO) mice are protected from TLR4‐mediated endotoxic shock and lethality. To identify the potential mechanisms involved, we examined the plasma levels of inflammatory cytokines/chemokines in the wild‐type (WT) and β‐arr‐1 and ‐2 KO mice after lipopolysaccharide (LPS, a TLR4 ligand) injection. Consistent with lethality, LPS‐induced inflammatory cytokine levels in the plasma were markedly decreased in both β‐arr‐1 and ‐2 KO, compared to WT mice. To further explore the cellular mechanisms, we obtained splenocytes (separated into CD11b+ and CD11b? populations) from WT, β‐arr‐1, and ‐2 KO mice and examined the effect of LPS on cytokine production. Similar to the in vivo observations, LPS‐induced inflammatory cytokines were significantly blocked in both splenocyte populations from the β‐arr‐2 KO compared to the WT mice. This effect in the β‐arr‐1 KO mice, however, was restricted to the CD11b? splenocytes. Our studies further indicate that regulation of cytokine production by β‐arrestins is likely independent of MAPK and IκBα‐NFκB pathways. Our results, however, suggest that LPS‐induced chromatin modification is dependent on β‐arrestin levels and may be the underlying mechanistic basis for regulation of cytokine levels by β‐arrestins in vivo. Taken together, these results indicate that β‐arr‐1 and ‐2 mediate LPS‐induced cytokine secretion in a cell‐type specific manner and that both β‐arrestins have overlapping but non‐redundant roles in regulating inflammatory cytokine production and endotoxic shock in mice. J. Cell. Physiol. 225: 406–416, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
105.
Soni Mishra Deepika Chaturvedi Naresh Kumar Poonam Tandon H.W. Siesler 《Chemistry and physics of lipids》2010,163(2):207-217
Oleic acid (cis-9-octadecenoic acid) is the most abundant cis-unsaturated fatty acid in nature; it is distributed in almost all organisms. In this work, we present a detailed vibrational spectroscopy investigation of Oleic acid by using infrared and Raman spectroscopies. These data are supported by quantum mechanical calculations, which allow us to characterize completely the vibrational spectra of this compound. The equilibrium geometry, harmonic vibrational frequencies, infrared intensities and activities of Raman scattering were calculated by ab initio Hartree-Fock (HF) and density functional theory (DFT) employing B3LYP with complete relaxation in the potential energy surface using 6-311G(d, p) basis set. After a proper scaling the calculated wavenumbers show a very good agreement with the observed values. A complete vibrational assignment is provided for the observed Raman and infrared spectra of Oleic acid. In this work, we also investigate the deviation of vibrational wavenumbers computed with two quantum chemical methods (HF and B3LYP). 相似文献
106.
Santosh Kumar Sharma Deepika Rawat Shrawan Kumar Arun Kumar Suman Kumaria Rama Rao Satyawada 《Trees - Structure and Function》2010,24(5):855-864
Prosopis cineraria, an important multipurpose tree and vital component of the otherwise fragile ecosystem of arid and semiarid regions of India.
It is highly drought tolerant and sprouts profusely during the extreme dry summer months when most other trees are leafless.
P. cineraria is known to exhibit comparable genetic variations at intra-specific and inter-population levels reflected through morphological
and cytogenetical diversity in regions, where this plant grows naturally. In the present study, single primer amplification
reaction (SPAR) methods have been used for determination of diversity at DNA level in 30 accessions of P. cineraria collected from different districts of Rajasthan. The analyses include the use of six minisatellite core sequence primers
for direct amplification of minisatellite DNA (DAMD), eight inter simple sequence repeats (ISSR) and 20 arbitrary primed decamer
sequences for random amplification (RAPD) reactions. Upon analysis of the data generated, all the three SPAR methods, either
independently and/or in combination, revealed wide range of genetic variation among accessions. Comparison of matrix of individual
SPAR method using MxComp component of NTSYS-pc 2.02 K software proving that analysis of natural genetic variation using combination
of SPAR methods particularly ISSR and DAMD, rather than an isolated approach, is very effective. Such an approach also yields
better information and reflection of the relatedness and affinities at intra-species and inter-population levels. Therefore,
it is opined that in order to reveal the intrinsic intra-specific variation, SPAR approaches involving more than one DNA marker
may reveal more authentic genetic variation in tropical tree species like P. cineraria. 相似文献
107.
Patel Ashok Kumar Lodha Deepika Shekhawat Narpat S. 《In vitro cellular & developmental biology. Plant》2020,56(6):817-826
In Vitro Cellular & Developmental Biology - Plant - Mitragyna parvifolia (Roxb.) Korth., commonly known as “Kadam,” is an endangered and pharmaceutically valued tree of the family... 相似文献
108.
Deepika Sharma Pradeep Kumar Vikramjeet Judge Rakesh Narang Erik De Clercq 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1161-1168
In the present study we have synthesized (4-nitrophenyl)-[2-(substituted phenyl)-benzoimidazol-1-yl]-methanones, (2-bromophenyl)-[2-(substituted phenyl)-benzoimidazol-1-yl]-methanone analogues (1–14) and evaluated them for their antimicrobial and antiviral potential. The results of antimicrobial screening indicated that none of the synthesized compounds were effective against the tested bacterial strains. Compounds 3, 11, 13 and compounds 5, 11, 12 were found to be active against Aspergillus niger and Candida albicans respectively, and may be further developed as antifungal agents. Furthermore, evaluation against a panel of different viruses pointed out the selective activity of compounds 5 and 6 against vaccinia virus and Coxsackie virus B4. 相似文献
109.
Sigrun M. Gustafsdottir Vebjorn Ljosa Katherine L. Sokolnicki J. Anthony Wilson Deepika Walpita Melissa M. Kemp Kathleen Petri Seiler Hyman A. Carrel Todd R. Golub Stuart L. Schreiber Paul A. Clemons Anne E. Carpenter Alykhan F. Shamji 《PloS one》2013,8(12)
Computational methods for image-based profiling are under active development, but their success hinges on assays that can capture a wide range of phenotypes. We have developed a multiplex cytological profiling assay that “paints the cell” with as many fluorescent markers as possible without compromising our ability to extract rich, quantitative profiles in high throughput. The assay detects seven major cellular components. In a pilot screen of bioactive compounds, the assay detected a range of cellular phenotypes and it clustered compounds with similar annotated protein targets or chemical structure based on cytological profiles. The results demonstrate that the assay captures subtle patterns in the combination of morphological labels, thereby detecting the effects of chemical compounds even though their targets are not stained directly. This image-based assay provides an unbiased approach to characterize compound- and disease-associated cell states to support future probe discovery. 相似文献
110.
Karunanidhi Kanchana Devi Sharma Deepika Asani Bhaduri David Kothamasi 《Geomicrobiology journal》2013,30(2):131-139
Bacterial HCN production is catalyzed by the membrane-bound enzyme HCN synthase. HCN synthase is encoded by a cluster of three genes, hcnABC, which form an operon. Polymorphism in the three genes may affect the catalytic efficiency of the enzyme and influence HCN production. In this study, we selected a ~570 bp portion of hcnAB gene consisting of a cysteine cluster at the 3′ end of hcnA that matches the iron-sulfur binding signature of 2[Fe–S] ferredoxins and the ADP binding-fold in the 5′ end of hcnB from 50 strains of HCN producing bacteria to analyze polymorphism in the gene. Both motifs have been credited to have a role in bacterial HCN synthesis. Analysis of the partial hcnAB gene showed that the bacteria grouped into four groups. Pairwise comparison of the distinctness ratios revealed that the HCN groups identified in this study were ecologically distinct populations and distinctness between the groups was reflected in HCN production by the bacteria. Supplementary materials are available for this article. Go to the publisher's online edition of Geomicrobiology Journal to view the supplemental file. 相似文献