14 research outputs found
Control of expression of the RNases J1 and J2 in bacillus subtilis
In Bacillus subtilis, the dual activity 5' exo- and endoribonucleases J1 and J2 are important players in mRNA and stable RNA maturation and degradation. Recent work has improved our understanding of their structure and mechanism of action and identified numerous RNA substrates. However, almost nothing is known about the expression of these enzymes. Here, we have identified the transcriptional and translational signals that control the expression of the rnjA (RNase J1) and rnjB (RNase J2) genes. While the rnjB gene is transcribed constitutively from a sigma A promoter, optimal expression of RNase J1 requires cotranscription and cotranslation with the upstream ykzG gene, encoding a protein of unknown function. In the absence of coupled translation, RNase J1 expression is decreased more than 5-fold. Transcription of the ykzG operon initiates at a sigma A promoter with a noncanonical -35 box that is required for optimal transcription. Biosynthesis of RNase J1 is autocontrolled within a small range (1.4-fold) and also slightly stimulated (1.4-fold) in the absence of RNase J2. These controls are weak but might be useful to maintain the overall RNase J level and possibly also equimolar amounts of the two nucleases in the cell that primarily act as a heterodimer in vivo. © 2014, American Society for Microbiology
Assessment of recent outbreaks of Dickeya sp (syn. Erwinia chrysanthemi) slow wilt in potato crops in Israel
Suspected Dickeya sp. strains were obtained from potato plants and tubers collected from commercial plots. The disease was observed on crops of various cultivars grown from seed tubers imported from the Netherlands during the spring seasons of 2004-2006, with disease incidence of 2-30% ( 10% in average). In addition to typical wilting symptoms on the foliage, in cases of severe infection, progeny tubers were rotten in the soil. Six strains were characterised by biochemical, serological and PCR amplification. All tests verified the strains as Dickeya sp. The repPCR and the biochemical assays showed that the strains isolated from blackleg diseased plants in Israel were very similar, if not identical to strains isolated from Dutch seed potatoes, suggesting that the infection in Israel originated from the Dutch seed. The strains were distantly related to D. dianthicola strains, typically found in potatoes in Western Europe, and were similar to biovar 3 D. dadanti or D. zeae. This is the first time that the presence of biovar 3 strains in potato in the Netherlands is described. One of the strains was used for pathogenicity assays on potato cvs Nicola and Mondial. Symptoms appeared 2 to 3 days after stem inoculation, and 7 to 10 days after soil inoculation. The control plants treated with water, or plants inoculated with Pectobacterium carotovorum, did not develop any symptoms with either method of inoculation. The identity of Dickeya sp. and P. carotovorum re- isolated from inoculated plants was confirmed by PCR and ELISA
Control of expression of the ribonucleases J1 and J2 in B. subtilis
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Assessment of recent outbreaks of Dickeya sp (syn. Erwinia chrysanthemi) slow wilt in potato crops in Israel
Suspected Dickeya sp. strains were obtained from potato plants and tubers collected from commercial plots. The disease was observed on crops of various cultivars grown from seed tubers imported from the Netherlands during the spring seasons of 2004-2006, with disease incidence of 2-30% ( 10% in average). In addition to typical wilting symptoms on the foliage, in cases of severe infection, progeny tubers were rotten in the soil. Six strains were characterised by biochemical, serological and PCR amplification. All tests verified the strains as Dickeya sp. The repPCR and the biochemical assays showed that the strains isolated from blackleg diseased plants in Israel were very similar, if not identical to strains isolated from Dutch seed potatoes, suggesting that the infection in Israel originated from the Dutch seed. The strains were distantly related to D. dianthicola strains, typically found in potatoes in Western Europe, and were similar to biovar 3 D. dadanti or D. zeae. This is the first time that the presence of biovar 3 strains in potato in the Netherlands is described. One of the strains was used for pathogenicity assays on potato cvs Nicola and Mondial. Symptoms appeared 2 to 3 days after stem inoculation, and 7 to 10 days after soil inoculation. The control plants treated with water, or plants inoculated with Pectobacterium carotovorum, did not develop any symptoms with either method of inoculation. The identity of Dickeya sp. and P. carotovorum re- isolated from inoculated plants was confirmed by PCR and ELISA
Promoting organ donation and transplantation among South Asians in the United Kingdom: the role of social networks in the South Asian community
The percentage of South Asians on the kidney transplant waiting list in the United Kingdom is 3 times their percentage in the general population. Obviously, organ donation and transplantation among South Asians in the United Kingdom needs improvement. In recent years, ethnically targeted campaigns in the mass media have specifically attempted to attract donors from the South Asian communities. A number of pilot studies have been done to evaluate the effectiveness of these initiatives in providing information about organ donation to South Asians. Results indicate that detailed information related to transplantation was learned mainly by people within the community receiving transplants and was transmitted through various informal community networks rather than through the resources provided by the Department of Health. This article provides an overview of who South Asians are and how these community networks were established. Transplant professionals must devise effective strategies to access these community networks, thereby raising the consciousness of transplantation among South Asians in the United Kingdom