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71.
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73.
Gupta L Srivastava K Singh S Puri SK Chauhan PM 《Bioorganic & medicinal chemistry letters》2008,18(11):3306-3309
A series of hybrid molecules 2-[3-(7-Chloro-quinolin-4-ylamino)-alkyl]-1-(substituted phenyl)-2,3,4,9-tetrahydro-1H-beta-carbolines have been synthesized and screened for their in vitro antimalarial activity against chloroquine-sensitive strains of Plasmodium falciparum. Compounds 26, 32, and 34 have shown MIC in the range of 0.05-0.11 microM and are in vitro several folds more active than chloroquine. 相似文献
74.
Plant Cell, Tissue and Organ Culture (PCTOC) - 相似文献
75.
Aeroallergens and pollinosis: Molecular and immunological characteristics of cloned pollen allergens
Affecting almost twenty percent of thepopulation in industrialized countries,allergic diseases such as asthma and seasonalrhinitis result from the development ofimmediate hypersensitivity to otherwiseinnocuous components of the environment. Pollen, the male gametophyte of flowering plantspecies, is one of the most predominant sourcesof environmental allergens, and a significantcause of allergic diseases. This reviewdiscusses the nature of pollen proteins asallergens, their effect on the human immunesystem and their mode of environmentaltransmission, including effects of theinteraction between pollen aeroallergens andair pollution. The influence of cross-reactivepollen allergens to the incidence of foodsensitivities is also discussed. Floweringplant species that possess allergenic pollen,identified with allergens cloned from thesespecies, are also discussed. 相似文献
76.
Genetic variability and association of ISSR markers with some biochemical traits in mulberry (Morus spp.) genetic resources available in India 总被引:2,自引:0,他引:2
Prasanta K. Kar Prem P. Srivastava Arvind K. Awasthi S. Raje Urs 《Tree Genetics & Genomes》2008,4(1):75-83
Utilizing intersimple sequence repeat (ISSR) markers, 18 mulberry (Morus spp.) germplasm collections were studied for genetic variability, phylogenetic relationship, and association with protein
and sugar content. The genetic polymorphism exhibited by ISSR primers was 100%, and the genetic diversity recorded among the
mulberry accessions had an average of 0.263 ± 0.094. Dendrogram (unweighted pair group method analysis) clustered the mulberry
accessions into two major groups, one comprised the accessions collected from north or northeast regions of India, and the
other comprised three subclusters and one isolate, i.e., Assamjati, a collection from Assam. Another subcluster contained
accessions collected from Kerala, which belong to Morus indica. These accessions of M. indica from Kerala were found to be genetically diverse from north and northeast India. Multidimensional scaling of the ISSR data
clearly separated the mulberry accessions according to their genetic diversity and protein content. Mulberry accessions were
arbitrarily grouped into three classes viz. very low, moderate, and high in terms of protein and sugar content using standard
statistical programs. Stepwise multiple regression analysis identified four ISSR markers (8351,600, 8355,600, 8222,500, and 8072,500) associated with protein content with highly positive correlation (p < 0.001) with linear curves with high F values (18.055 to 48.674; p < 0.001). In case of sugar content, four ISSR markers viz. 812900, 8171,500, 8261,500, and 8108,000 showed negative correlation. Hence, DNA markers for proteins seem promising and may be used in marker-assisted breeding program. 相似文献
77.
Ilker Kudret Sariyer Nana Merabova Prem Kumer Patel Tijana Knezevic Alessandra Rosati Maria C. Turco Kamel Khalili 《PloS one》2012,7(9)
JC virus, JCV, is a human neurotropic polyomavirus whose replication in glial cells causes the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML). In addition, JCV possesses oncogenic activity and expression of its transforming protein, large T-antigen (T-Ag), in several experimental animals induces tumors of neural origin. Further, the presence of JCV DNA and T-Ag have been repeatedly observed in several human malignant tissues including primitive neuroectodermal tumors and glioblastomas. Earlier studies have demonstrated that Bag3, a member of the Bcl-2-associated athanogene (Bag) family of proteins, which is implicated in autophagy and apoptosis, is downregulated upon JCV infection of glial cells and that JCV T-Ag is responsible for suppressing the activity of the BAG3 promoter. Here, we investigated the possible impact of Bag3 on T-Ag expression in JCV-infected human primary glial cells as well as in cells derived from T-Ag-induced medulloblastoma in transgenic animals. Results from these studies revealed that overexpression of Bag3 drastically decreases the level of T-Ag expression by inducing the autophagic degradation of the viral protein. Interestingly, this event leads to the inhibition of JCV infection of glial cells, suggesting that the reduced levels of T-antigen seen upon the overexpression of Bag3 has a biological impact on the viral lytic cycle. Results from protein-protein interaction studies showed that T-Ag and Bag3 physically interact with each other through the zinc-finger of T-Ag and the proline rich domains of Bag3, and this interaction is important for the autophagic degradation of T-Ag. Our observations open a new avenue of research for better understanding of virus-host interaction by investigating the interplay between T-Ag and Bag3, and their impact on the development of JCV-associated diseases. 相似文献
78.
The kidney uses mixtures of five osmolytes to counter the stress induced by high urea and NaCl concentrations. The individual roles of most of the osmolytes are unclear, and three of the five have not yet been thermodynamically characterized. Here, we report partial molar volumes and activity coefficients of glycerophosphocholine (GPC), taurine, and myo-inositol. We derive their solvation behavior from the experimental data using Kirkwood-Buff theory. We also provide their solubility data, including solubility data for scyllo-inositol. It turns out that renal osmolytes fall into three distinct classes with respect to their solvation. Trimethyl-amines (GPC and glycine-betaine) are characterized by strong hard-sphere-like self-exclusion; urea, taurine, and myo-inositol have a tendency toward self-association; sorbitol and most other nonrenal osmolytes have a relatively constant, intermediate solvation that has components of both exclusion and association. The data presented here show that renal osmolytes are quite diverse with respect to their solvation patterns, and they can be further differentiated based on observations from experiments examining their effect on macromolecules. It is expected, based on the available surface groups, that each renal osmolyte has distinct effects on various classes of biomolecules. This likely allows the kidney to use specific combinations of osmolytes independently to fine-tune the chemical activities of several types of molecules. 相似文献
79.
Motoaki Sato Prem Kumar Sinha Jesus Torres-Bacete Akemi Matsuno-Yagi Takao Yagi 《The Journal of biological chemistry》2013,288(34):24705-24716
The proton-translocating NADH-quinone oxidoreductase (complex I/NDH-1) contains a peripheral and a membrane domain. Three antiporter-like subunits in the membrane domain, NuoL, NuoM, and NuoN (ND5, ND4 and ND2, respectively), are structurally similar. We analyzed the role of NuoN in Escherichia coli NDH-1. The lysine residue at position 395 in NuoN (NLys395) is conserved in NuoL (LLys399) but is replaced by glutamic acid (MGlu407) in NuoM. Our mutation study on NLys395 suggests that this residue participates in the proton translocation. Furthermore, we found that MGlu407 is also essential and most likely interacts with conserved LArg175. Glutamic acids, NGlu133, MGlu144, and LGlu144, are corresponding residues. Unlike mutants of MGlu144 and LGlu144, mutation of NGlu133 scarcely affected the energy-transducing activities. However, a double mutant of NGlu133 and nearby KGlu72 showed significant inhibition of these activities. This suggests that NGlu133 bears a functional role similar to LGlu144 and MGlu144 but its mutation can be partially compensated by the nearby carboxyl residue. Conserved prolines located at loops of discontinuous transmembrane helices of NuoL, NuoM, and NuoN were shown to play a similar role in the energy-transducing activity. It seems likely that NuoL, NuoM, and NuoN pump protons by a similar mechanism. Our data also revealed that NLys158 is one of the key interaction points with helix HL in NuoL. A truncation study indicated that the C-terminal amphipathic segments of NTM14 interacts with the Mβ sheet located on the opposite side of helix HL. Taken together, the mechanism of H+ translocation in NDH-1 is discussed. 相似文献
80.
Tissue-specific DNase I-sensitive sites of the maize P gene and their changes upon epimutation 总被引:1,自引:0,他引:1
Gertrud Lund O. Prem Das Joachim Messing 《The Plant journal : for cell and molecular biology》1995,7(5):797-807
A map has been developed of nuclease-hypersensitive sites of P-rr , the standard allele of the P -locus of Zea mays L. Using a traditional DNase I assay, eight such sites have been found that are specific for the expressing tissue and span a region of more than 25 kb of the P -locus, making it one of the largest plant genes yet described. The maps of the standard allele have also been compared with the recently described moderately stable P-pr allele, which arose from epimutation. Six of the eight sites exhibit the same tissue-specificity in P-pr plants, while two stay repressed as in non-expressing tissues of plants with the standard allele. Interestingly, the two repressed sites coincide with two hypermethylated restriction sites that have previously been correlated with the expression potential of the P-pr allele. On the other hand, four of the DNase I sites, coinciding with CpG islands that were not hypermethylated by the epimutation, also showed no differences in their sensitivity to DNase I between the standard allele and the P-pr allele. This suggests that the epimutation affects both site-specific methylation changes and a specific local chromatin structure of the P gene involved in its regulation. 相似文献