6 research outputs found

    A single methyltransferase YefA (RlmCD) catalyses both m5U747 and m5U1939 modifications in Bacillus subtilis 23S rRNA

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    Methyltransferases that use S-adenosylmethionine (AdoMet) as a cofactor to catalyse 5-methyl uridine (m5U) formation in tRNAs and rRNAs are widespread in Bacteria and Eukaryota, and are also found in certain Archaea. These enzymes belong to the COG2265 cluster, and the Gram-negative bacterium Escherichia coli possesses three paralogues. These comprise the methyltransferases TrmA that targets U54 in tRNAs, RlmC that modifies U747 in 23S rRNA and RlmD that is specific for U1939 in 23S rRNA. The tRNAs and rRNAs of the Gram-positive bacterium Bacillus subtilis have the same three m5U modifications. However, as previously shown, the m5U54 modification in B. subtilis tRNAs is catalysed in a fundamentally different manner by the folate-dependent enzyme TrmFO, which is unrelated to the E. coli TrmA. Here, we show that methylation of U747 and U1939 in B. subtilis rRNA is catalysed by a single enzyme, YefA that is a COG2265 member. A recombinant version of YefA functions in an E. coli m5U-null mutant adding the same two rRNA methylations. The findings suggest that during evolution, COG2265 enzymes have undergone a series of changes in target specificity and that YefA is closer to an archetypical m5U methyltransferase. To reflect its dual specificity, YefA is renamed RlmCD

    clinicopathologic and survival characteristics of 282 patients

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    Malignant pleural mesothelioma (MPM) is a relatively rare, but aggressive tumor that causes high mortality. The major risk factor involved in the etiology is environmental and occupational exposure to asbestos. The optimal modality of therapy is controversial. The present study retrospectively evaluated the data pertinent to 282 patients who were examined and treated in 11 different medical oncology centers in Turkey. There were 161 males (57.1 %) and 121 females (42.9 %), with a mean age of 56.38 +/- A 12.07 years. Surgery was used in 74 patients, 21 patients (28.4 %) received only chemotherapy and 28 patients (37.8 %) received chemoradiotherapy after surgery. The median survival in patients who were administered adjuvant therapy after surgery was 24 months, while the median survival in patients who had only surgery was 6 months (p = 0.029). 106 patients were administered pemetrexed-platinum combination and 35 patients were administered gemcitabine-platinum combination as front-line chemotherapy. Median survival, 1- and 2-year survival rates in patients who received platinum analogues and pemetrexed or gemcitabine combinations were found statistically similar (p = 0.15). The median survival for all patients with MPM in our study was 18 months. The main factors influencing the overall survival were stage of the disease (p = 0.020), performance status (p < 0.001), asbestos exposure (p = 0.030) and mesothelioma histological subtypes (p < 0.001). Results of our study suggest that multi-modality treatment regimens consisting of surgery, radiotherapy and chemotherapy prolong overall survival. Survival rates in patients who received combining platinum analogues with pemetrexed or gemcitabine as front-line chemotherapy were found similar

    Miscible Polymer Blends

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