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61.
Huntemann M Lu M Nolan M Lapidus A Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Ovchinikova G Pati A Chen A Palaniappan K Land M Hauser L Jeffries CD Detter JC Brambilla EM Rohde M Spring S Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Mavromatis K 《Standards in genomic sciences》2011,4(3):303-311
Hippea maritima (Miroshnichenko et al. 1999) is the type species of the genus Hippea, which belongs to the family Desulfurellaceae within the class Deltaproteobacteria. The anaerobic, moderately thermophilic marine sulfur-reducer was first isolated from shallow-water hot vents in Matipur Harbor, Papua New Guinea. H. maritima was of interest for genome sequencing because of its isolated phylogenetic location, as a distant next neighbor of the genus Desulfurella. Strain MH(2) (T) is the first type strain from the order Desulfurellales with a completely sequenced genome. The 1,694,430 bp long linear genome with its 1,723 protein-coding and 57 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
62.
Lang E Teshima H Lucas S Lapidus A Hammon N Deshpande S Nolan M Cheng JF Pitluck S Liolios K Pagani I Mikhailova N Ivanova N Mavromatis K Pati A Tapia R Han C Goodwin L Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Brambilla EM Kopitz M Rohde M Göker M Tindall BJ Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(1):81-90
63.
Pati A Zhang X Lapidus A Nolan M Lucas S Del Rio TG Tice H Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Chen A Palaniappan K Hauser L Jeffries CD Brambilla EM Röhl A Mwirichia R Rohde M Tindall BJ Sikorski J Wirth R Göker M Woyke T Detter JC Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Land M 《Standards in genomic sciences》2011,4(2):210-220
Oceanithermus profundus Miroshnichenko et al. 2003 is the type species of the genus Oceanithermus, which belongs to the family Thermaceae. The genus currently comprises two species whose members are thermophilic and are able to reduce sulfur compounds and nitrite. The organism is adapted to the salinity of sea water, is able to utilize a broad range of carbohydrates, some proteinaceous substrates, organic acids and alcohols. This is the first completed genome sequence of a member of the genus Oceanithermus and the fourth sequence from the family Thermaceae. The 2,439,291 bp long genome with its 2,391 protein-coding and 54 RNA genes consists of one chromosome and a 135,351 bp long plasmid, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
64.
65.
Minimal CK2 activity required for yeast growth 总被引:3,自引:0,他引:3
Protein kinase CK2 is essential for the growth of Saccharomyces cerevisiae. Yeast cells that lack the functional genes coding for both the catalytic subunits of protein kinase CK2 can grow only if they are complemented by exogenous cDNAs coding for this subunit. A series of deletion mutants of CK2α from Xenopus laevis was constructed. These mutants that have carboxyl end deletions yield a CK2α product that varies over four orders of magnitude in its capacity to phosphorylate casein in vitro. Complementation of yeast RPG41-1a, a mutant defective in CKA1 and CKA2 genes, with wild-type X. laevis CK2α and with cDNAs coding for truncated CK2α having amino acids 1–328 and 1–327 resulted in cells that grew in gal-minimal media at 30 ∘C as well as the cells harboring the yeast CKA2 gene. However, the growth was significantly diminished when cells were complemented with X. laevis CK2α containing 1–326 amido acids. This mutant has 0.6% of the catalytic activity of the wild-type enzyme. Yeast cells that expressed CK2α 1–324 and 1–323 which have 10-and 100-fold less activity, respectively, were not able to grow. The growth of cells containing the CK2α 1–326 mutant was very sensitive to temperature, and minimal growth was observed at 37 ∘C. This mutant was also more sensitive to UV radiation but was not significantly affected by 0.4 M NaCl.Both authors contributed equally to this work 相似文献
66.
Sarciron ME Terreux R Prieto Y Cortes M Cuellar MA Tapia RA Domard M Walchshofer N Pétavy AF 《Parasite (Paris, France)》2005,12(3):251-258
33 polycyclic derivatives have been studied and tested on Leishmania donovani and L. major promastigotes. Their antileishmanial activity was assessed in vitro and an assay of their cytotoxicity was realized on human myelomonocytic cell line. The reference molecules used in the assays were amphotericin B and pentamidine. Among the compounds tested, 29 possess an antileishmanial activity; 25 of those were more active against L. donovani than amphotericin B, and nine were as effective as amphotericin B against L. major. Many synthesized derivatives were more active against L. donovani than against L. major. The cytotoxicity studies have shown that among the thirty-three derivatives tested, 12 molecules have an IC50 towards THP-1 cells about equal than that reference drugs, the 21 other derivatives are much less toxic. A 3D QSAR study was undertaken and has permitted to predict activity against L. donovani and L. major and to highlight critical area to optimize activity against the two species. 相似文献
67.
Felipe?A.?Cisternas Gladys?Tapia Miguel?Arredondo Denise?Cartier-Ugarte Pamela?Romanque Walter?D.?Sierralta María?T.?Vial Luis?A.?Videla Magdalena?ArayaEmail author 《Biometals》2005,18(5):541-551
Cu is an essential trace element capable of producing toxic effects in animals and man when ingested acutely or chronically
in excess. Although chronic Cu exposure is increasingly recognized as a public health issue, its early effects remain largely
unknown. We approached the significance of a moderate chronic Cu load in young rats to correlate early hepatic histopathological
changes with functional alterations of liver cells. For this purpose, supplementation with 1200 ppm of Cu in rat food for
16 weeks was chosen. In these conditions, Cu load elicited a significant decrease in growth curves. There were mild light
microscopy alterations in Cu-treated rats, although increasing intracellular Cu storage was correlated with longer Cu exposure
both by histological and biochemical measurements. Ultrastructural alterations included lysosomal inclusions as well as mitochondrial
and nuclear changes. Liver perfusion studies revealed higher rates of basal O2 consumption and colloidal carbon-induced O2 uptake in Cu-treated rats, with enhanced carbon-induced O2/carbon uptake ratios and NF-κB DNA binding activity. These changes were time-dependent and returned to control values after
12 or16 weeks. It is concluded that subchronic Cu loading in young rats induces early hepatic morphological changes, with
enhancement in Küpffer cell-dependent respiratory burst activity and NF-κB DNA binding, cellular responses that may prevent
or alleviate the hepatotoxicity of the metal. 相似文献
68.
69.
Brain cells have a highly active oxidative metabolism, yet they contain only low to moderate superoxide dismutase and catalase activities. Thus, their antioxidant defenses rely mainly on cellular reduced glutathione levels. In this work, in cortical neurons we characterized viability and changes in reduced and oxidized glutathione levels in response to a protocol of iron accumulation. We found that massive death occurred after 2 days in culture with 10 microM Fe. Surviving cells developed an adaptative response that included increased synthesis of GSH and the maintenance of a glutathione-based reduction potential. These results highlight the fundamental role of glutathione homeostasis in the antioxidant response and provide novel insights into the adaptative mechanisms of neurons subjected to progressive iron loads. 相似文献
70.
Tapia G Fernández V Pino C Ardiles R Videla LA 《Free radical biology & medicine》2006,40(9):1628-1635
Recently, we reported that 3,3',5-triiodothyronine (T3) induces the expression of redox-sensitive genes as a nongenomic mechanism of T3 action. In this study, we show that T3 administration to rats (daily doses of 0.1 mg/kg ip for 3 consecutive days) induced a calorigenic response and liver glutathione depletion as an indication of oxidative stress, with higher levels of interleukin (IL)-6 in serum (ELISA) and hepatic STAT3 DNA binding (EMSA), which were maximal at 48-72 h after treatment. Under these conditions, the protein expression of the acute-phase proteins haptoglobin and beta-fibrinogen is significantly augmented, a change that is suppressed by pretreatment with alpha-tocopherol (100 mg/kg ip) or gadolinium chloride (10 mg/kg iv) before T3. It is concluded that T3 administration induces the acute-phase response in rat liver by a redox mechanism triggered at the Kupffer cell level, in association with IL-6 release and activation of the STAT3 cascade, a response that may contribute to reestablishing homeostasis in the liver and extrahepatic tissues exhibiting oxidative stress. 相似文献