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81.
Ogino C Negi Y Daido H Kanemasu M Kondo A Kuroda S Tanizawa K Shimizu N Fukuda H 《Biochimica et biophysica acta》2001,1530(1):23-31
A membrane-bound phospholipase D (PLD) has been identified and isolated in a soluble form from an actinomycete, Streptoverticillium cinnamoneum. The enzyme has a monomeric structure with a molecular size of about 37 kDa, being the smallest among the enzymes so far reported. The enzyme catalyzes the hydrolysis of phosphatidylethanolamine and phosphatidylserine as preferred substrates, but not the transphosphatidylation reaction of their phospholipid groups to ethanol. Together with the absence of immunochemical cross-reactivity, these enzymatic properties demonstrate that the membrane-bound enzyme is distinct from the extracellular enzyme recently characterized and cloned from the same bacterial strain [C. Ogino et al., J. Biochem. 125 (1999) 263-269] and is therefore regarded as a novel prokaryotic PLD. 相似文献
82.
Yamada K Senju S Nakatsura T Murata Y Ishihara M Nakamura S Ohno S Negi A Nishimura Y 《Biochemical and biophysical research communications》2001,280(4):1169-1176
To identify the target autoantigens in Vogt-Koyanagi-Harada disease, we made use of an immunoscreening of a bovine uveal cDNA expression library with serum samples obtained from patients with Vogt-Koyanagi-Harada disease. We identified a novel bovine antigen and homologous human autoantigen and designated it as UACA (uveal autoantigen with coiled coil domains and ankyrin repeats). mRNA of human UACA is expressed most abundantly in skeletal muscles and in various human tissues, including choroid, retina, and epidermal melanocytes. IgG autoantibodies were quantitated in an ELISA, using recombinant C-terminal 18.0% fragment of human UACA. The prevalence of IgG anti-UACA autoantibodies in patients with panuveitis (Vogt-Koyanagi-Harada disease, Beh?et's disease, sarcoidosis) was significantly higher than that in healthy controls (19.6-28.1% vs 0%, P < 0.05) indicating that autoimmunity directed against UACA is a common phenomenon in these diseases. 相似文献
83.
Jayaprakasha GK Negi PS Anandharamakrishnan C Sakariah KK 《Zeitschrift für Naturforschung. C, Journal of biosciences》2001,56(1-2):40-44
Curcumin, the yellow coloring pigment of turmeric is produced industrially from turmeric oleoresin. The mother liquor after isolation of curcumin from oleoresin known as curcumin removed turmeric oleoresin (CRTO) was extracted three times with n-hexane at room temperature for 30 min to obtain turmeric oil. The turmeric oil was subjected to fractional distillation under vacuum to get two fractions. These fractions were tested for antifugal activity against Aspergillus flavus, A. parasiticus, Fusarium moniliforme and Penicillium digitatum by spore germination method. Fraction II was found to be more active. The chemical constituents of turmeric oil, fraction I and fraction II were determined by GC and identified by GC-MS. Aromatic turmerone, turmerone and curlone were major compounds present in fraction II along with other oxygenated compounds. 相似文献
84.
Maneesh Kumar Roshan Kamal Topno Manas Ranjan Dikhit Bhawana Ganesh Chandra Sahoo Major Madhukar Krishna Pandey Pradeep Das 《Journal of cellular biochemistry》2019,120(10):18298-18308
The arthropod-transmitted chikungunya virus has emerged as an epidemic menace that causes debilitating polyarthritis. With this life-threatening impact on humans, the possible treatment requires to cure the viral infectivity. But, devoid of any vaccine against the chikungunya virus (CHIKV), there is a need to develop a novel chemotherapeutic strategy to treat this noxious infection. CHIKV carries highly compact P23pro-zbd structure that possesses potential RNA-binding surface domains which extremely influences the use of RNA template during genome replication at the time of infection and pathogenesis. Therefore, computational approaches were used to explore the novel small molecule inhibitors targeting P23pro-zbd domain. The tertiary structure was modeled and optimized using in silico approaches. The results obtained from PROCHECK (93.1% residues in favored regions), ERRAT (87.480 overall model quality) and ProSA (Z-score: −11.72) revealed the reliability of the proposed model. Interestingly, a previously reported inhibitor, chloroquine possesses good binding affinities with the target domain. In-depth analysis revealed that chloroquine derivatives such as didesethyl chloroquine hydroxyacetamide, cletoquine, hydroxychloroquine exhibited a better binding affinity. Notably, MD simulation analysis exhibited that Thr1312, Ala1355, Ala1356, Asn1357, Asp1364, Val1366, Cys1367, Ala1401, Gly1403, Ser1443, Tyr1444, Gly1445, Asn1459, and Thr1463 residues are the key amino acid responsible for stable ligand-protein interaction. The results obtained from this study provide new insights and advances the understanding to develop a new approach to consider effective and novel drug against chikungunya. However, a detailed in vivo study is required to explore its drug likeliness against this life-threatening disease. 相似文献
85.
Anukriti Sharma Naseer Sangwan Vivek Negi Puneet Kohli Jitendra Paul Khurana Desiraju Lakshmi Narsimha Rao Rup Lal 《BMC genomics》2015,16(1)
Background
Phylogenetic heterogeneity across Pseudomonas genus is complemented by its diverse genome architecture enriched by accessory genetic elements (plasmids, transposons, and integrons) conferring resistance across this genus. Here, we sequenced a stress tolerant genotype i.e. Pseudomonas sp. strain RL isolated from a hexachlorocyclohexane (HCH) contaminated pond (45 mg of total HCH g−1 sediment) and further compared its gene repertoire with 17 reference ecotypes belonging to P. stutzeri, P. mendocina, P. aeruginosa, P. psychrotolerans and P. denitrificans, representing metabolically diverse ecosystems (i.e. marine, clinical, and soil/sludge). Metagenomic data from HCH contaminated pond sediment and similar HCH contaminated sites were further used to analyze the pan-genome dynamics of Pseudomonas genotypes enriched across increasing HCH gradient.Results
Although strain RL demonstrated clear species demarcation (ANI ≤ 80.03%) from the rest of its phylogenetic relatives, it was found to be closest to P. stutzeri clade which was further complemented functionally. Comparative functional analysis elucidated strain specific enrichment of metabolic pathways like α-linoleic acid degradation and carbazole degradation in Pseudomonas sp. strain RL and P. stutzeri XLDN-R, respectively. Composition based methods (%codon bias and %G + C difference) further highlighted the significance of horizontal gene transfer (HGT) in evolution of nitrogen metabolism, two-component system (TCS) and methionine metabolism across the Pseudomonas genomes used in this study. An intact mobile class-I integron (3,552 bp) with a captured gene cassette encoding for dihydrofolate reductase (dhfra1) was detected in strain RL, distinctly demarcated from other integron harboring species (i.e. P. aeruginosa, P. stutzeri, and P. putida). Mobility of this integron was confirmed by its association with Tnp21-like transposon (95% identity) suggesting stress specific mobilization across HCH contaminated sites. Metagenomics data from pond sediment and recently surveyed HCH adulterated soils revealed the in situ enrichment of integron associated transposase gene (TnpA6100) across increasing HCH contamination (0.7 to 450 mg HCH g−1 of soil).Conclusions
Unlocking the potential of comparative genomics supplemented with metagenomics, we have attempted to resolve the environment and strain specific demarcations across 18 Pseudomonas gene complements. Pan-genome analyses of these strains indicate at astoundingly diverse metabolic strategies and provide genetic basis for the cosmopolitan existence of this taxon.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1488-2) contains supplementary material, which is available to authorized users. 相似文献86.
This communication describes for the first time an efficient and reproducible protocol for large-scale multiplication of Bambusa nutans. Nodal segments collected from field-grown clumps and cultured on Murashige and Skoog (MS) medium supplemented with 4.4 μM
benzylaminopurine (BA) and 2.32 μM kinetin (Kin) gelled with 0.2% gelrite yielded 80% aseptic cultures with 100% bud-break.
The in vitro-formed shoots obtained after bud-break were successfully multiplied in MS liquid medium supplemented with 13.2 μM
BA, 2.32 μM Kin, and 0.98 μM indole-3-butyric acid (IBA). Sub-culturing of shoots every 3 weeks on fresh multiplication medium
yielded a consistent proliferation rate of 3.5-fold. Shoot clusters containing three to five shoots were successfully rooted
with 100% success on half-strength MS liquid medium supplemented with 9.8 μM IBA, 2.85 μM indole-3-acetic acid (IAA), 2.68 μM
naphthaleneacetic acid (NAA), and 3% sucrose. Plantlets grown in vitro were acclimatized and subsequently transferred to the
field. Inter-simple sequence repeat analysis has confirmed the genetic uniformity of the tissue-cultured plants up to 27 passages. 相似文献
87.
Sunil Bala Wesley Devendra Prasad Maurya Hari Sharan Goyal Sangeeta Negi 《World journal of microbiology & biotechnology》2013,29(12):2353-2357
In the current study, ferritic stainless grades AISI 439 and AISI 444 were investigated as possible construction materials for machinery and equipment in the cane-sugar industry. Their performance in corrosive cane-sugar juice environment was compared with the presently used low carbon steel AISI 1010 and austenitic stainless steel AISI 304. The Tafel plot electrochemical technique was used to evaluate general corrosion performance. Microbiologically influenced corrosion (MIC) behaviour in sugarcane juice environment was studied. Four microbial colonies were isolated from the biofilms on the metal coupon surfaces on the basis of their different morphology. These were characterized as Brevibacillus parabrevis, Bacillus azotoformans, Paenibacillus lautus and Micrococcus sp. The results of SEM micrographs showed that AISI 439 and AISI 304 grades had suffered maximum localized corrosion. MIC investigations revealed that AISI 444 steel had the best corrosion resistance among the tested materials. However from the Tafel plots it was evident that AISI 1010 had the least corrosion resistance and AISI 439 the best corrosion resistance. 相似文献
88.
89.
Mutagen sensitive strains (mus) in Drosophila are known for their hypersensitivity to mutagens and environmental carcinogens. Accordingly, these mutants were grouped in pre- and post-replication repair pathways. However, studying mutants belonging to one particular repair pathway may not be adequate for examining chemical-induced genotoxicity when other repair pathways may neutralize its effect. To test whether both pre-and post-replication pathways are involved and effect of Cr(III)- and Cr(VI)-induced genotoxicity in absence or presence of others, we used double mutant approach in D. melanogaster. We observed DNA damage as evident by changes in Comet assay DNA migration in cells of larvae of Oregon R(+) and single mutants of pre- (mei-9, mus201 and mus210) and post- (mei-41, mus209 and mus309) replication repair pathways and also in double mutants of different combinations (pre-pre, pre-post and post-post replication repair) exposed to increasing concentrations of Cr(VI) (0.0, 5.0, 10.0 and 20.0 μg/ml) for 48 h. The damage was greater in pre-replication repair mutants after exposure to 5.0 μg/ml Cr(VI), while effects on Oregon R(+) and post replication repair mutants were insignificant. Post-replication repair mutants revealed significant DNA damage after exposure to 20.0 μg/ml Cr(VI). Further, double mutants generated in the above repair categories were examined for DNA damage following Cr(VI) exposure and a comparison of damage was studied between single and double mutants. Combinations of double mutants generated in the pre-pre replication repair pathways showed an indifferent interaction between the two mutants after Cr(VI) exposure while a synergistic interaction was evident in exposed post-post replication repair double mutants. Cr(III) (20.0 μg/ml) exposure to these strains did not induce any significant DNA damage in their cells. The study suggests that both pre- and post-replication pathways are affected in Drosophila by Cr(VI) leading to genotoxicity, which may have consequences for metal-induced carcinogenesis. 相似文献
90.
A genomics approach reveals that aroma production in apple is controlled by ethylene predominantly at the final step in each biosynthetic pathway 总被引:6,自引:0,他引:6 下载免费PDF全文