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71.
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Ilaria Guerini Nicola J Geisler Hengyao Niu Mareike Herzog Israel Salguero Bernardo Ochoa‐Montaño Emmanuelle Viré Patrick Sung David J Adams Thomas M Keane Stephen P Jackson 《The EMBO journal》2015,34(11):1509-1522
DNA double-strand break (DSB) repair by homologous recombination (HR) requires 3′ single-stranded DNA (ssDNA) generation by 5′ DNA-end resection. During meiosis, yeast Sae2 cooperates with the nuclease Mre11 to remove covalently bound Spo11 from DSB termini, allowing resection and HR to ensue. Mitotic roles of Sae2 and Mre11 nuclease have remained enigmatic, however, since cells lacking these display modest resection defects but marked DNA damage hypersensitivities. By combining classic genetic suppressor screening with high-throughput DNA sequencing, we identify Mre11 mutations that strongly suppress DNA damage sensitivities of sae2Δ cells. By assessing the impacts of these mutations at the cellular, biochemical and structural levels, we propose that, in addition to promoting resection, a crucial role for Sae2 and Mre11 nuclease activity in mitotic DSB repair is to facilitate the removal of Mre11 from ssDNA associated with DSB ends. Thus, without Sae2 or Mre11 nuclease activity, Mre11 bound to partly processed DSBs impairs strand invasion and HR. 相似文献
73.
Elvira Brunelli Ilaria Bernabò Francesca Coscarelli Daniele La Russa Sandro Tripepi 《Zoomorphology》2015,134(1):135-147
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75.
Streptococcus agalactiae Capsule Polymer Length and Attachment Is Determined by the Proteins CpsABCD
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Methyl jasmonate affects phenolic metabolism and gene expression in blueberry (Vaccinium corymbosum) 下载免费PDF全文
Giacomo Cocetta Mara Rossoni Claudio Gardana Ilaria Mignani Antonio Ferrante Anna Spinardi 《Physiologia plantarum》2015,153(2):269-283
Blueberry (Vaccinium corymbosum) is a fruit very much appreciated by consumers for its antioxidant potential and health‐promoting traits. Its beneficial potential properties are mainly due to a high content of anthocyanins and their amount can change after elicitation with methyl jasmonate. The aim of this work is to evaluate the changes in expression of several genes, accumulation of phenolic compounds and alterations in antioxidant potential in two different blueberry cultivars (‘Duke’ and ‘Blueray’) in response to methyl jasmonate (0.1 mM). Results showed that 9 h after treatment, the expression of phenylalanine ammonium lyase, chalcone synthase and anthocyanidin synthase genes was stimulated more in the ‘Blueray’ variety. Among the phenols measured an increase was recorded also for epicatechin and anthocyanin concentrations. ‘Duke’ is a richer sourche of anthocyanins compared to ‘Blueray’, treatment with methyl jasmonate promoted in ‘Blueray’ an increase in pigments as well as in the antioxidant potential, especially in fully ripe berries, but treated ‘Duke’ berries had greater levels, which were not induced by methyl jasmonate treatment. In conclusion, methyl jasmonate was, in some cases, an effective elicitor of phenolic metabolism and gene expression in blueberry, though with different intensity between cultivars. 相似文献
78.
Finore Ilaria Kasavi Ceyda Poli Annarita Romano Ida Oner Ebru Toksoy Kirdar Betul Dipasquale Laura Nicolaus Barbara Lama Licia 《World journal of microbiology & biotechnology》2011,27(10):2425-2433
This study reports the purification and biochemical characterization of a raw starch-digesting α-amylase from Geobacillus thermoleovorans subsp. stromboliensis subsp. nov. (strain PizzoT). The molecular weight was estimated to be 58 kDa by SDS–PAGE. The enzyme was highly active over a wide range of pH from
4.0–10.0. The optimum temperature of the enzyme was 70°C. It showed extreme thermostability in the presence of Ca2+, retaining 50% of its initial activity after 90 h at 70°C. The enzyme efficiently hydrolyzed 20% (w/v) of raw starches, concentration
normally used in starch industries. The α-amylase showed an high stability in presence of many organic solvents. In particular
the residual activity was of 73% in presence of 15% (v/v) ethyl alcohol, which corresponds to ethanol yield in yeast fermentation
process. By analyzing its complete amyA gene sequence (1,542 bp), the enzyme was proposed to be a new α-amylase. 相似文献
79.
Miles TJ Barfoot C Brooks G Brown P Chen D Dabbs S Davies DT Downie DL Eyrisch S Giordano I Gwynn MN Hennessy A Hoover J Huang J Jones G Markwell R Rittenhouse S Xiang H Pearson N 《Bioorganic & medicinal chemistry letters》2011,21(24):7483-7488
As part of our wider efforts to exploit novel mode of action antibacterials, we have discovered a series of cyclohexyl-amide compounds that has good Gram positive and Gram negative potency. The mechanism of action is via inhibition of bacterial topoisomerases II and IV. We have investigated various subunits in this series and report advanced studies on compound 7 which demonstrates good PK and in vivo efficacy properties. 相似文献
80.
Miles TJ Axten JM Barfoot C Brooks G Brown P Chen D Dabbs S Davies DT Downie DL Eyrisch S Gallagher T Giordano I Gwynn MN Hennessy A Hoover J Huang J Jones G Markwell R Miller WH Minthorn EA Rittenhouse S Seefeld M Pearson N 《Bioorganic & medicinal chemistry letters》2011,21(24):7489-7495
We have identified a series of amino-piperidine antibacterials with a good broad spectrum potency. We report the investigation of various subunits in this series and advanced studies on compound 8. Compound 8 possesses good pharmacokinetics, broad spectrum antibacterial activity and demonstrates oral efficacy in a rat lung infection model. 相似文献