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Biodegradation of chlorpyrifos by bacterial consortium isolated from agriculture soil 总被引:2,自引:0,他引:2
C Sasikala S Jiwal P Rout M Ramya 《World journal of microbiology & biotechnology》2012,28(3):1301-1308
Organophosphorous pesticides are widely used in agriculture to control major insect pests. Chlorpyrifos is one of the major
organophosphorous pesticides which is used to control insects including termites, beetles. The widespread use of these pesticides
is hazardous to the environment and also toxic to mammals, thus it is essential to remove the same from the environment. From
the chlorpyrifos contaminated soil nine morphologically different bacterial strains, one actinomycete and two fungal strains
were isolated. Among those isolates four bacterial strains which were more efficient were developed as consortium. The four
bacterial isolates namely Pseudomonas putida (NII 1117), Klebsiella sp., (NII 1118), Pseudomonas stutzeri (NII 1119), Pseudomonas aeruginosa (NII 1120) present in the consortia were identified on the basis of 16S rDNA analysis. The intracellular fractions of the
consortium exhibited more organophosphorus hydrolase activity (0.171 ± 0.003 U/mL/min). The degradation studies were carried
out at neutral pH and temperature 37°C with chlorpyrifos concentration 500 mg L−1. LC-mass spectral analysis showed the presence of metabolites chlopyrifos-oxon and Diethylphosphorothioate. These results
highlight an important potential use of this consortium for the cleanup of chlorpyrifos contaminated pesticide waste in the
environment. 相似文献
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Prabakaran Ravichandran Sudhakar Baluchamy Bindhu Sadanandan Ramya Gopikrishnan Santosh Biradar Vani Ramesh Joseph C. Hall Govindarajan T. Ramesh 《Apoptosis : an international journal on programmed cell death》2010,15(12):1507-1516
Our previous report on multiwall carbon nanotubes (MWCNT) has demonstrated the generation of reactive radicals and depletion
of intracellular antioxidants which in turn cause cell death through activation of caspases. The molecular mechanism of cellular
death due to MWCNT is not clear yet. In this study, we investigated the signaling pathways implicated in MWCNT-induced apoptosis
in rat lung epithelial cells. First, we assessed the DNA damage in response to MWCNT treatment and showed the significant
DNA damage as compared to control. The collapse of the mitochondrial membrane integrity, release of cytochrome c into the
cytosol, reduction in cellular ATP content, increased levels of mitochondrial apoptogenic factor and activation and nuclear
translocation of NF-κB were observed in MWCNT treated cells. In addition, a time-dependent induction of phosphorylated IκBα and its degradation
were detected in cells exposed to MWCNT. Furthermore, MWCNT activated several death related proteins including apoptosis inducing
factor, p53, p21 and bax. Together, our results suggest that signaling pathways such as NF-κB and AP-1 are activated upon MWCNT treatment for cellular cytotoxicity. 相似文献
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Joseph O. Ayeni Ramya Varadarajan Oindrila Mukherjee David T. Stuart Frank Sprenger Martin Srayko Shelagh D. Campbell 《Genetics》2014,196(1):197-210
Eukaryotic organisms use conserved checkpoint mechanisms that regulate Cdk1 by inhibitory phosphorylation to prevent mitosis from interfering with DNA replication or repair. In metazoans, this checkpoint mechanism is also used for coordinating mitosis with dynamic developmental processes. Inhibitory phosphorylation of Cdk1 is catalyzed by Wee1 kinases that phosphorylate tyrosine 15 (Y15) and dual-specificity Myt1 kinases found only in metazoans that phosphorylate Y15 and the adjacent threonine (T14) residue. Despite partially redundant roles in Cdk1 inhibitory phosphorylation, Wee1 and Myt1 serve specialized developmental functions that are not well understood. Here, we expressed wild-type and phospho-acceptor mutant Cdk1 proteins to investigate how biochemical differences in Cdk1 inhibitory phosphorylation influence Drosophila imaginal development. Phosphorylation of Cdk1 on Y15 appeared to be crucial for developmental and DNA damage-induced G2-phase checkpoint arrest, consistent with other evidence that Myt1 is the major Y15-directed Cdk1 inhibitory kinase at this stage of development. Expression of non-inhibitable Cdk1 also caused chromosome defects in larval neuroblasts that were not observed with Cdk1(Y15F) mutant proteins that were phosphorylated on T14, implicating Myt1 in a novel mechanism promoting genome stability. Collectively, these results suggest that dual inhibitory phosphorylation of Cdk1 by Myt1 serves at least two functions during development. Phosphorylation of Y15 is essential for the premitotic checkpoint mechanism, whereas T14 phosphorylation facilitates accumulation of dually inhibited Cdk1–Cyclin B complexes that can be rapidly activated once checkpoint-arrested G2-phase cells are ready for mitosis. 相似文献
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Beebe D Garcia C Wang X Rajagopal R Feldmeier M Kim JY Chytil A Moses H Ashery-Padan R Rauchman M 《The International journal of developmental biology》2004,48(8-9):845-856
Members of the TGFbeta superfamily of growth and differentiation factors, including the TGFbeta, BMP, activin and nodal families, play important signaling roles throughout development. This paper summarizes some of the functions of these ligands in lens development. Targeted deletion of the genes encoding one of the BMP receptors, Alk3 (BMP receptor-1A), showed that signaling through this receptor is essential for normal lens development. Lenses lacking Alk3 were smaller than normal, with thin epithelial layers. The fiber cells of Alk3 null lenses became vacuolated and degenerated within the first week after birth. Lenses lacking Alk3 function were surrounded by abnormal mesenchymal cells, suggesting that the lenses provided inappropriate signals to surrounding tissues. Lens epithelial and fiber cells contained endosomes that were associated with activated (phosphorylated) SMAD1 and SMAD2. Endosomal localization of pSMAD1 was reduced in the absence of Alk3 signaling. The presence of pSMAD2 in lens fiber cell nuclei and the observation that the activin antagonist follistatin inhibited lens cell elongation suggested that an activin-like molecule participates in lens fiber cell differentiation. Lenses deficient in type II TGFbeta receptors were clear and had fiber cells of normal morphology. This suggests that TGFbeta signaling is not essential for the normal differentiation of lens fiber cells. The targeted deletion of single or multiple receptors of the TGFbeta superfamily in the lens should further characterize the role of these signaling molecules in lens development. This approach may also provide a useful way to define the downstream pathways that are activated by these receptors during the development of the lens and other tissues. 相似文献
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Antonio B. Fernandez Gregory A. Panza Benjamin Cramer Saurav Chatterjee Ramya Jayaraman Wen-Chih Wu 《PloS one》2015,10(11)
Background
Age-related macular degeneration (AMD) is the leading cause of vision loss and blindness in people over 65 years old in the United States and has been associated with cardiovascular risk and decreased survival. There is conflicting data, however, regarding the contribution of AMD to the prediction of stroke.Aim
To determine whether AMD is a risk indicator for incident stroke in a meta-analysis of available prospective and retrospective cohort studies published in the English literature.Methods
We performed a systematic literature search of all studies published in English with Pub Med and other databases from 1966 to August 2014, reporting stroke incidence in patients with macular degeneration. Two investigators independently extracted the data. A random effects model was used to report Odds ratios (OR), with corresponding 95% confidence intervals (CI). Meta-regression using a mixed linear model was used to understand potential heterogeneity amongst studies.Results
We identified 9 studies that reported stroke incidence in patients with and without early AMD (N = 1,420,978). No significant association was found between early AMD with incident stroke. Combined, these 9 studies demonstrated random effects (OR, 1.12; CI, 0.86–1.47; I2 = 96%). Meta-regression on baseline covariates of age, sex, and year of publication did not significantly relate to heterogeneity.Conclusions
We found no significant relationship between AMD and incident stroke. Further studies are needed to clarify other causes of decreased survival in patients with AMD. 相似文献60.
Lavanya Joshi Meenakshi Ponnana Ramya Sivangala Lakshmi Kiran Chelluri Prathiba Nallari Sitaramaraju Penmetsa Vijayalakshmi Valluri Sumanlatha Gaddam 《PloS one》2015,10(9)