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Hiroko K. Kitamoto Sadahiro Ohmomo Koichi Amaha Tomotaro Nishikawa Yuzuru Limura 《Biotechnology letters》1998,20(8):725-728
Killer strain of Kluyveromyces lactis was constructed to prevent the aerobic deterioration of silage by disruption of KlPCK1 gene encoding phosphoenolpyruvate carboxykinase (PEPCK). The disruptants are defective in their ability of growth on lactic acid as a sole carbon source. The PEPCK activity was also deficient in the disruptants. The growth rate on lactose medium and the killing activity were equal to those of the parental strain. © Rapid Science Ltd. 1998 相似文献
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An interplay among experimental studies of protein synthesis, evolutionary theory, and comparisons of DNA sequence data has shed light on the roles of natural selection and genetic drift in ‘silent’ DNA evolution. 相似文献
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Akiyoshi Taniguchi Koichi Matsuzaki Katsuya Nakano Mikio Kan Wallace L. Mckeehan 《In vitro cellular & developmental biology. Animal》1998,34(3):232-238
Summary The type III receptor for transforming growth factor beta (TGFβ), which exhibits no kinase activity, binds TGFβ1 and TGFβ2
and is involved in assembly and activity of the multi-subunit TGFβ signal transduction complex. Recently we showed that TGFβ
receptor type III (TβRIII) can participate in a complex composed of the dimeric TGFβ ligand and a type III, II, and I receptor
subunit. The interaction of the TβRIII subunit with TβRII is TGFβ-dependent, whereas interaction with TβRI is TGFβ-independent.
Here we use coexpression of the three types of TGFβ receptors in baculoviral-infected insect cells to determine which parts
of the unglycosylated TβRIII receptor participate in the binding of TGFβ, the TGFβ-dependent interaction with TβRII and the
TGFβ-independent interaction with TβRI. The results suggest that the first 500 amino acid residues in the aminoterminal portion
of TβRIII exhibit all three properties. 相似文献
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Involvement of Prolonged Ras Activation in Thrombopoietin-Induced Megakaryocytic Differentiation of a Human Factor-Dependent Hematopoietic Cell Line 总被引:9,自引:3,他引:6
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The grafting of l-phenylalanine onto low molecular weight chitosan is accomplished by using carbodiimide as a coupling agent. As increase in the amount of phenylalanine in feed, the grafting chain length increases, while a number of grafting chains hardly change. The obtained product, LMWCts-g-Phe, performs sphere with an average size of ~80 nm when the % grafting is less than 123. The complexes of the LMWCts-g-Phe and DNA (LMWCts-g-Phe/DNA) prepared by a complex coacervation method possess various shapes with an average size of ~50–150 nm and a negatively charged surface. The LMWCts-g-Phe and its complex show very reduced toxicity to fibroblast cells. The release of DNA from the complex is very fast in high pH media (tris buffer, pH 8.0 and carbonate buffer, pH 9.5), and relatively slow or more sustainable in neutral and low pH ones (PBS, pH 7.4 and citric acid/trisodium citrate buffer, pH 3.0). The results suggest that the LMWCts-g-Phe be an alternative promising carrier for negatively charged active molecules. 相似文献
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