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101.
W L Sung C K Luk D M Zahab J R Barbier M Lafontaine G E Willick 《Biochemical and biophysical research communications》1991,181(1):481-485
Expression of the human parathyroid hormone (PTH) gene in E. coli yielded intact PTH and PTH-(8-84). To determine if PTH-(8-84) is the result of a competing translation initiated from methionine codon-8 or degradation of the intact PTH, twelve new gene constructs with or without an internal ribosome-binding site (iRBS) in the PTH-(1-5) region were prepared via substitution with degenerate codons. Expression of constructs without iRBS produced only intact PTH. Constructs with weak iRBS, including one that resembles the cDNA sequence, yielded PTH-(8-84) as a minor product. In contrast, constructs with strong iRBS produced predominantly or exclusively this shorter analogue. 相似文献
102.
Yveta Lhotáková Luká? Plí?til Alena Morávková Pavel Kubát Kamil Lang Jitka Forstová Ji?í Mosinger 《PloS one》2012,7(11)
Novel biomaterials based on hydrophilic polycaprolactone and polyurethane (Tecophilic®) nanofibers with an encapsulated 5,10,5,20-tetraphenylporphyrin photosensitizer were prepared by electrospinning. The doped nanofiber textiles efficiently photo-generate O2(1Δg), which oxidize external chemical and biological substrates/targets. Strong photo-virucidal effects toward non-enveloped polyomaviruses and enveloped baculoviruses were observed on the surface of these textiles. The photo-virucidal effect was confirmed by a decrease in virus infectivity. In contrast, no virucidal effect was detected in the absence of light and/or the encapsulated photosensitizer. 相似文献
103.
Production of cyclopiazonic acid by Aspergillus flavus is reported for the first time. A procedure for its production by agitated solid substrate fermentation on red wheat is described along with the isolation procedure and physical and chemical properties of this indole derivative. The compound has been found to exert antibacterial activity. 相似文献
104.
We have isolated a cDNA clone for chicken thioredoxin by differential screening of a cDNA library. The protein product which this clone encodes is very similar to other thioredoxins, and it displays thioredoxin activity when expressed in Escherichia coli. This clone represents the first metazoan thioredoxin for which the protein or nucleic acid sequence is known. Comparison of the chicken thioredoxin protein sequence with those from bacteria and plants indicates structural features that appear to be essential for activity. Transformation of chicken embryo fibroblasts by Rous sarcoma virus elevates the level of thioredoxin mRNA whereas the level of thioredoxin mRNA in a nonproliferative tissue (brain) is much lower than in chicken embryo fibroblasts. 相似文献
105.
Chak Hon Luk Camila Valenzuela Magdalena Gil La Swistak Perrine Bomme Yuen-Yan Chang Adeline Mallet Jost Enninga 《PLoS pathogens》2021,17(4)
Salmonella Typhimurium (S. Typhimurium) is an enteric bacterium capable of invading a wide range of hosts, including rodents and humans. It targets different host cell types showing different intracellular lifestyles. S. Typhimurium colonizes different intracellular niches and is able to either actively divide at various rates or remain dormant to persist. A comprehensive tool to determine these distinct S. Typhimurium lifestyles remains lacking. Here we developed a novel fluorescent reporter, Salmonella INtracellular Analyzer (SINA), compatible for fluorescence microscopy and flow cytometry in single-bacterium level quantification. This identified a S. Typhimurium subpopulation in infected epithelial cells that exhibits a unique phenotype in comparison to the previously documented vacuolar or cytosolic S. Typhimurium. This subpopulation entered a dormant state in a vesicular compartment distinct from the conventional Salmonella-containing vacuoles (SCV) as well as the previously reported niche of dormant S. Typhimurium in macrophages. The dormant S. Typhimurium inside enterocytes were viable and expressed Salmonella Pathogenicity Island 2 (SPI-2) virulence factors at later time points. We found that the formation of these dormant S. Typhimurium is not triggered by the loss of SPI-2 effector secretion but it is regulated by (p)ppGpp-mediated stringent response through RelA and SpoT. We predict that intraepithelial dormant S. Typhimurium represents an important pathogen niche and provides an alternative strategy for S. Typhimurium pathogenicity and its persistence. 相似文献
106.
107.
Biomechanics and Modeling in Mechanobiology - Digital models based on finite element (FE) analysis are widely used in orthopaedics to predict the stress or strain in the bone due to... 相似文献
108.
Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
109.
Marcel Karabín Lukáš Jelínek Pavel Kotrba Rudolf Cejnar Pavel Dostálek 《Biotechnology advances》2018,36(3):691-706
Beer production is one of the oldest known traditional biotechnological processes, but is nowadays facing increasing demands not only for enhanced product quality, but also for improved production economics. Targeted genetic modification of a yeast strain is one way to increase beer quality and to improve the economics of beer production. In this review we will present current knowledge on traditional approaches for improving brewing strains and for rational metabolic engineering. These research efforts will, in the near future, lead to the development of a wider range of industrial strains that should increase the diversity of commercial beers. 相似文献
110.