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981.
Chávez E Zazueta C García N Martínez-Abundis E Pavón N Hernández-Esquivel L 《Journal of bioenergetics and biomembranes》2008,40(2):77-84
Under the action of carboxyatractyloside or fatty acids, adenine nucleotide translocase switches its function from nucleotide
carrier to modulator of the opening of a non-specific pore. In addition to the effect of these agents, this modification in
activity is, in some way, dependent on the influence of the lipid milieu of the membrane. Cardiolipin is, among other membrane
phospholipids, the one that interacts the most with the translocase. This work shows that 10-N-nonyl acridine orange and acridine orange, probes for this phospholipid, modify the sensitivity of the translocase to carboxyatractyloside,
oleate, and palmitate to induce permeability transition. The results also show that these probes stimulate the release of
mitochondrial cytochrome c, and increase labeling of the carrier by eosin 5-maleimide. Based on the aforementioned it is proposed that the increase
in sensitivity is due to a conformational change in the translocase, induced by the binding of the probe to cardiolipin. 相似文献
982.
Tribouillard-Tanvier D Dos Reis S Gug F Voisset C Béringue V Sabate R Kikovska E Talarek N Bach S Huang C Desban N Saupe SJ Supattapone S Thuret JY Chédin S Vilette D Galons H Sanyal S Blondel M 《PloS one》2008,3(5):e2174
Background
6-Aminophenanthridine (6AP) and Guanabenz (GA, a drug currently in use for the treatment of hypertension) were isolated as antiprion drugs using a yeast-based assay. These structurally unrelated molecules are also active against mammalian prion in several cell-based assays and in vivo in a mouse model for prion-based diseases.Methodology/Principal Findings
Here we report the identification of cellular targets of these drugs. Using affinity chromatography matrices for both drugs, we demonstrate an RNA-dependent interaction of 6AP and GA with the ribosome. These specific interactions have no effect on the peptidyl transferase activity of the ribosome or on global translation. In contrast, 6AP and GA specifically inhibit the ribosomal RNA-mediated protein folding activity of the ribosome.Conclusion/Significance
6AP and GA are therefore the first compounds to selectively inhibit the protein folding activity of the ribosome. They thus constitute precious tools to study the yet largely unexplored biological role of this protein folding activity. 相似文献983.
Induction of stress response renders human tumor cell lines resistant to curcumin-mediated apoptosis: role of reactive oxygen intermediates 总被引:8,自引:0,他引:8
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Ashok Khar A. Mubarak Ali B. V. V. Pardhasaradhi Ch. Varalakshmi Rana Anjum A. Leela Kumari 《Cell stress & chaperones》2001,6(4):368-376
Curcumin, a well-known dietary pigment derived from Curcuma longa, has been shown to be a potent antiinflammatory, antioxidant, and anticarcinogenic compound. The present study was designed to investigate the cytotoxic potential of curcumin against a range of human tumor cell lines in an attempt to understand its mechanism of action, which may lead to its possible therapeutic applications. We have shown that different cancer cell lines differ in their sensitivity to curcumin. Cell lines established from malignancies like leukemia, breast, colon, hepatocellular, and ovarian carcinomas underwent apoptosis in the presence of curcumin, whereas cell lines from lung, kidney, prostate, cervix, CNS malignancies, and melanomas showed resistance to the cytotoxic effects of curcumin. Sensitivity of the cancer cell lines to curcumin correlated with the generation of superoxide radicals as determined by the reduction of ferricytochrome C. Curcumin-resistant tumor cell lines showed significantly higher production of Hsp70, thus mounting a stress response and protecting the cells from the apoptotic cell death. These observations yield clues toward understanding the regulation of the cell death machinery by the stress proteins. Interestingly, curcumin had no effect on nontransformed cell lines, which showed neither superoxide generation nor the induction of a stress response. These observations demonstrate that curcumin is an interesting molecule with varied actions, depending on the cell type. 相似文献
984.
Exploration of Phytoconstituents from Mussaenda roxburghii and Studies of Their Antibiofilm Effect
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Arpita Sarkar Antu Das Padmani Sandhu Biswanath Dinda Yusuf Akhter Surajit Bhattacharjee Utpal Ch. De 《化学与生物多样性》2017,14(10)
In the context of ethno botanical importance with no phytochemical investigations, Mussaenda roxburghii have been investigated to explore it's phytoconstituents and studies of their antibiofilm activity. Four compounds have been isolated from the aerial parts of this plant and were characterized as 2α,3β,19α,23‐tetrahydroxyurs‐12‐en‐28‐oic acid ( 1 ), β‐sitosterol glucoside ( 4 ), lupeol palmitate ( 5 ), and myoinositol ( 6 ). All these compounds were tested for antibacterial and antibiofilm activity against Pseudomonas aeruginosa. Compound 1 exhibited three times more antibiofilm activity with minimum inhibitory concentration (MIC) at 0.74 mm compared to that of streptomycin. Molecular docking studies exhibited a very high binding affinity of 1 with P. aeruginosa quorum sensing proteins and motility associated proteins viz. LasR and PilB, PilY1, PilT, respectively. Compound 1 was also found to be non‐cytotoxic against sheep RBC and murine peritoneal macrophages at selected sub‐MIC doses. 相似文献
985.
Indices of anti‐dengue immunoglobulin G subclasses in adult Mexican patients with febrile and hemorrhagic dengue in the acute phase
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Araceli Posadas‐Mondragón José Leopoldo Aguilar‐Faisal Adolfo Chávez‐Negrete Edith Guillén‐Salomón Verónica Alcántara‐Farfán Lucero Luna‐Rojas Amanda Marineth Ávila‐Trejo Judith del Carmen Pacheco‐Yépez 《Microbiology and immunology》2017,61(10):433-441
986.
Smita Kumari Raj Kumar Regar Abhay Bajaj Ratnasekhar Ch Gubbala Naga Venkata Satyanarayana Mohana Krishna Reddy Mudiam Natesan Manickam 《Indian journal of microbiology》2017,57(1):60-67
A polyaromatic hydrocarbon degrading bacterium was isolated from a petroleum contaminated site and designated as Stenotrophomonas sp. strain IITR87. It was found to utilize pyrene, phenanthrene and benzo(a)pyrene as sole carbon source, but not anthracene, chrysene and fluoranthene. Gas chromatography and mass spectroscopy analysis resulted in identification of pyrene metabolites namely monohydroxypyrene, 4-oxa-pyrene-5-one, dimethoxypyrene and monohydroxyphenanthrene. Southern hybridization using naphthalene dioxygenase gene (nidA) as probe against the DNA of strain IITR87 revealed the presence of nidA gene. PCR analysis suggests dispersed occurrence of nid genes in the genome instead of a cluster as reported in a PAH-degrading Mycobacterium vanbaalenii PYR-1. The nid genes in strain IITR87, dioxygenase large subunit (nidA), naphthalene dioxygenase small subunit (nidB) and aldehyde dehydrogenase gene (nidD) showed more than 97 % identity to the reported nid genes from Mycobacterium vanbaalenii PYR-1. Most significantly, the biodegradation of PAHs was enhanced 25–60 % in the presence of surfactants rhamnolipid and Triton X-100 due to increased solubilization and bioavailability. These results could be useful for the improved biodegradation of high-molecular-weight PAHs in contaminated habitats. 相似文献
987.
988.
SNPs selected by information content outperform randomly selected microsatellite loci for delineating genetic identification and introgression in the endangered dark European honeybee (Apis mellifera mellifera)
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Irene Muñoz Dora Henriques Laura Jara J. Spencer Johnston Julio Chávez‐Galarza Pilar De La Rúa M. Alice Pinto 《Molecular ecology resources》2017,17(4):783-795
The honeybee (Apis mellifera) has been threatened by multiple factors including pests and pathogens, pesticides and loss of locally adapted gene complexes due to replacement and introgression. In western Europe, the genetic integrity of the native A. m. mellifera (M‐lineage) is endangered due to trading and intensive queen breeding with commercial subspecies of eastern European ancestry (C‐lineage). Effective conservation actions require reliable molecular tools to identify pure‐bred A. m. mellifera colonies. Microsatellites have been preferred for identification of A. m. mellifera stocks across conservation centres. However, owing to high throughput, easy transferability between laboratories and low genotyping error, SNPs promise to become popular. Here, we compared the resolving power of a widely utilized microsatellite set to detect structure and introgression with that of different sets that combine a variable number of SNPs selected for their information content and genomic proximity to the microsatellite loci. Contrary to every SNP data set, microsatellites did not discriminate between the two lineages in the PCA space. Mean introgression proportions were identical across the two marker types, although at the individual level, microsatellites' performance was relatively poor at the upper range of Q‐values, a result reflected by their lower precision. Our results suggest that SNPs are more accurate and powerful than microsatellites for identification of A. m. mellifera colonies, especially when they are selected by information content. 相似文献
989.
B. B. Bazarova M. Ts. Itigilova A. Dulmaa P. V. Matafonov G. Ts. Tsybekmitova N. A. Tashlykova E. Yu. Afonina Ch. Ayushsuren 《Biology Bulletin》2017,44(2):193-202
The diversity of communities and the quantitative parameters of hydrobionts of 17 lakes of the Onon-Toreisk Plain in Northeastern Mongolia during the low-water period are analyzed. The organisms revealed in the lakes include 35 species of phytoplankton, 35 species of zoobenthos, 31 species of zooplankton, and 14 species of hydrophytes. Chara virgata, a representative of charophytes, was revealed in Mongolia for the first time. The greatest species diversity of the communities of hydrobionts is seen in oligohaline lakes. The highest quantitative parameters of communities of phytoplankton and zoobenthos are typical for Gurmiin Lake. 相似文献