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441.
From the rice leaf cDNA library, we have cloned a cDNA encoding rice chloroplast translational elongation factor EF-Tu (tufA). The rice tufA cDNA clone contains 1678 nucleotides and codes for a 467 amino acid protein including a putative chloroplast transit peptide of 59 amino acid residues. The predicted molecular mass of the mature protein is approximately 45 kDa. This cDNA clone contains the 61 nucleotides of the 5' untranslated region (UTR) and the 213 nucleotides of 3' UTR. Amino acid sequence identity of the rice tufA with the mature chloroplast EF-Tu proteins of tobacco, pea, arabidopsis, and soybean ranges from 83% to 86%. The deduced polypeptide of the rice tufA cDNA contains GTP binding domains in its N-terminal region and chloroplast EF-Tu signature regions in the C-terminal region. The rice tufA appears to exist as a single copy gene, although its homologues of maize and oat exist as multiple copy genes. The rice tufA gene is located in chromosome 1 and is more highly expressed in the leaf than in root tissue. 相似文献
442.
A cellular RNA-binding protein enhances internal ribosomal entry site-dependent translation through an interaction downstream of the hepatitis C virus polyprotein initiation codon 总被引:7,自引:0,他引:7 下载免费PDF全文
Kim JH Paek KY Ha SH Cho S Choi K Kim CS Ryu SH Jang SK 《Molecular and cellular biology》2004,24(18):7878-7890
Translational initiation of hepatitis C virus (HCV) mRNA occurs by internal entry of ribosomes into an internal ribosomal entry site (IRES) at the 5' nontranslated region. A region encoding the N-terminal part of the HCV polyprotein has been shown to augment the translation of HCV mRNA. Here we show that a cellular protein, NS1-associated protein 1 (NSAP1), augments HCV mRNA translation through a specific interaction with an adenosine-rich protein-coding region within the HCV mRNA. The overexpression of NSAP1 specifically enhanced HCV IRES-dependent translation, and knockdown of NSAP1 by use of a small interfering RNA specifically inhibited the translation of HCV mRNA. An HCV replicon RNA capable of mimicking the HCV proliferation process in host cells was further used to confirm that NSAP1 enhances the translation of HCV mRNA. These results suggest the existence of a novel mechanism of translational enhancement that acts through the interaction of an RNA-binding protein with a protein coding sequence. 相似文献
443.
Kim DS Jung MY Sin Y Kim DW Paek J Kim RN Park IS Kook JK Nam SH Kim A Kang A Park HS Choi SH Chang YH 《Journal of bacteriology》2012,194(10):2758
A new Clostridium species has been isolated from pear orchard soil in Daejeon, Republic of Korea. The isolate, Clostridium arbusti SL206(T) (KCTC 5449(T)), showed a nitrogenase activity as well as an organic acid production. Here we first report the draft genome sequence of a novel species in the genus Clostridium within the largest Gram-positive group. 相似文献
444.
445.
Jayoung Paek Mi-Hwa Lee Byung-Chun Kim Byoung-In Sang Woon Kee Paek Tae-Eun Jin Yeseul Shin In-Soon Park Young-Hyo Chang 《Antonie van Leeuwenhoek》2014,106(3):577-583
A Gram-stain positive, strict anaerobe, spore-forming, motile rod-shaped bacterial strain with peritrichous flagella, designated YMB-57T, was isolated from the intestine of a cinereous vulture (Aegypius monachus) in Korea. StrainYMB-57T was found to show optimal growth at 37 °C, pH 7.5 and 1.0 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain YMB-57T belongs to the genus Clostridium and is most closely related to the type strains of Clostridium subterminale (96.9 % sequence similarity), Clostridium thiosulfatireducens (96.7 %) and Clostridium sulfidigenes (96.6 %). The main fermentation end-products identified following growth in PYG medium were acetate, butyrate, ethanol, propanol, carbon dioxide and hydrogen. Peptone was converted to ethanol, and butanol, whereas glucose was fermented to ethanol. The major cellular fatty acids were identified as C16:0, C18:1 ω9c, and C18:1 ω9c DMA and the DNA G+C content was determined to be 34.0 mol%. Phenotypic and phylogenetic differences indicate that strain YMB-57T is distinct from other Clostridium species. It is proposed that strain YMB-57T be classified as the type strain of a novel species of the genus Clostridium, with the name Clostridium vulturis sp. nov. The type strain is YMB-57T (=KCTC 15114T = JCM 17998T). 相似文献
446.
Jayaraman Selvaraj Shazia Fathima JH Venkatacalam Sivabalan Umapathy Vidhya Rekha Rajagopal Ponnulakshmi Veeraraghavan Vishnupriya Malathi Kullappan Radhika Nalinakumari Sreekandan Surapaneni Krishna Mohan Periyasamy Vijayalakshmi 《Bioinformation》2021,17(1):200
Cornulin (CRNN) is linked with tumour progression. Therefore, it is of interest to document data on the molecular modeling of cornulin (CRNN) for docking with phytocompounds (Pyrazinamide, Anisotine, Vasicinone, Vasicoline) from Justicia adhatoda L. Thus, we document the optimal binding features of these compounds with the cornulin model for further consideration. 相似文献
447.
Atmospheric-pressure cold plasma (APCP) using helium/oxygen was developed and tested as a suitable sterilization method in a clinical environment. The sterilizing effect of this method is not due to UV light, which is known to be the major sterilization factor of APCP, but instead results from the action of reactive oxygen radicals. Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae deposited on a nitrocellulose filter membrane or Bacillus subtilis spores deposited on polypropylene plates were exposed to helium/oxygen plasma generated with AC input power at 10 kHz, 6 kV. After plasma treatment, nitrocellulose filter membranes were overlaid on fresh solid media and CFUs were counted after incubation overnight. D-values were 18 sec for E. coli, 19 sec for S. aureus, 1 min 55 sec for S. cerevisiae, and 14 min for B. subtilis spores. D-values of bacteria and yeast were dependent on the initial inoculation concentration, while the D-value of B. subtilis spores showed no correlation. When treated cells were observed with a scanning electron microscope, E. coli was more heavily damaged than S. aureus, S. cerevisiae exhibited peeling, and B. subtilis spores exhibited shrunken morphology. Results showed that APCP using helium/oxygen has many advantages as a sterilization method, especially in a clinical environment with conditions such as stable temperature, unlimited sample size, and no harmful gas production. 相似文献
448.
Y. H. Dewir D. Chakrabarty E. J. Hahn K. Y. Paek 《In vitro cellular & developmental biology. Plant》2006,42(3):291-297
Summary A method for the micropropagation of Spathiphyllum cannifolium is presented using shoot tip proliferation onto Murashige and Skoog (MS) medium supplemented with different plant growth
regulator concentrations and combinations. The proliferation responses were significantly influenced by the cytokinin type
and concentrations. Supplementation of the medium with benzyladenine (BA; 4.44–13.32 μM) increased the shoot proliferation rate significantly as compared to other treatments. When cytokinins were used with auxin
(indole-3-butyric acid, IBA and naphthalene acetic acid. NAA), the number of shoots per explant increased in comparison with
treatments with BA alone. The largest number of shoots, 9.3 per explant, was obtained with 13.32 μM BA and 4.9 μM IBA. Different MS medium strengths and sucrose concentrations were used with the aim to stimulate in vitro shoot proliferation. Full MS medium with 30 gl−1 sucrose was found to be suitable for shoot tip culture of Spathiphyllum. Comparative studies between gelled medium and bioreactor culture [continuous immersion (with or without net) and temporary
immersion in liquid media using ebb and flood] revealed that shoot multiplication and growth were more efficient in continuous
immersion (with net) bioreactor with low cytokinin-supplemented media. Plantlets from the bioreactor were cultured hydroponically
for 30 d and 100% of plants were rooted and acelimatized successfully. Rapid and efficient multiplication rate in bioreactor
and successful transfer to greenhouse makes this protocol suitable for large-scale multiplication of this important foliage
plant. 相似文献
449.
Stimulation of m1 and of m3 muscarinic receptors has previously been shown to increase intracellular cAMP levels in a variety of cells. Although the mechanism underlying this response is not fully understood, it has been hypothesized to be secondary to the IP3-mediated rise in intracellular calcium. In order to determine whether other means of elevating intracellular calcium also raise cAMP levels, we stimulated SK-N-SH human neuroblastoma cells with bradykinin or with maitotoxin. Both of these agents stimulated phospholipase C, stimulated inositol phosphate release and elevated cAMP levels, thus demonstrating that this cAMP response is not unique to muscarinic receptor stimulation. 相似文献
450.
Tidal volume measurements based on the sum of volume displacements of the rib cage (RC) and abdomen (Ab) are limited in accuracy when changes in posture occur. To elucidate the underlying sources of error, five subjects performed spinal flexion-extension isovolume maneuvers and then performed Konno-Mead isovolume maneuvers at different lung volumes while erect, with the spine fully flexed, and at intermediate degrees of spinal flexion. RC and Ab dimensions were measured with respiratory inductance plethysmograph belts, and spinal flexion was assessed by a pair of magnetometers measuring the xiphi-Ab distance (Xi). RC and Ab volume-motion coefficients (alpha and beta, respectively) were calculated from the slope (-beta/alpha) of the Konno-Mead isovolume lines. We found that 1) spinal flexion with constant lung volume mainly increases the RC dimension, thereby displacing the Konno-Mead isovolume lines, and 2) spinal flexion decreases the -beta/alpha by decreasing beta. The error related to displacement averaged 28.4 +/- 15% of vital capacity, whereas the error related to changes in beta averaged 14 +/- 6% (SD). The systematic relationship of these errors with the degree of spinal flexion provides a mechanism whereby the addition of Xi to RC and Ab displacements significantly (P less than 0.001) improves volume estimates. 相似文献