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71.
The production of recombinant proteins in plants is an active area of research and many different high-value proteins have
now been produced in plants. Tobacco leaves have many advantages for recombinant protein production particularly since they
allow field production without seeds, flowers or pollen and therefore provide for contained production. Despite these biosafety
advantages recombinant protein accumulation in leaves still needs to be improved. Elastin-like polypeptides are repeats of
the amino acids “VPGXG” that undergo a temperature dependant phase transition and have utility in the purification of recombinant
proteins but can also enhance the accumulation of recombinant proteins they are fused to. We have used a 11.3 kDa elastin-like
polypeptide as a fusion partner for three different target proteins, human interleukin-10, murine interleukin-4 and the native
major ampullate spidroin protein 2 gene from the spider Nephila clavipes. In both transient analyses and stable transformants the concentrations of the fusion proteins were at least an order of
magnitude higher for all of the fusion proteins when compared to the target protein alone. Therefore, fusions with a small
ELP tag can be used to significantly enhance the accumulation of a range of different recombinant proteins in plant leaves.
An erratum to this article can be found at 相似文献
72.
73.
Alex Paton 《BMJ (Clinical research ed.)》1983,286(6370):1030-1031
74.
Summary The authors show that in certain isolated tissues (cornea of frog, mouse cancer) the mitotic processes continue during at least one hour. They are very strongly stimulated by heat and also by mitogenetic radiation. In the case of the cancer cells new mitoses are promoted in considerable number. A detailed analysis of both energy factors leads to the conclusion that they effect a disturbance of the unstable constellations (structures) of the elementary particles in the cell-body. Thus a certain degree of disorganisation of its plasma seems to stimulate cell-division. This statement is, in the opinion of the authors a proof that cell-division is controlled by a field, the trajectories of the elementary particles of the cell-body being a function of their coordinates relative to the cell-axes.
Résumé Les auteurs démontrent que dans certains tissus survivants (la cornée des yeux de grenouille et le cancer de souris) les mitoses continuent leur processus d'évolution durant au moins une heure. Par l'application de chaleur aussi bien que par l'irradiation mitogénétique on peut accélérer beaucoup le rhythme des mitoses en cours d'évolution et provoquer (dans les cas de cancer seulement) l'apparition d'un nombre considérable de nouvelles mitoses. L'analyse de l'action de ces deux facteurs d'énergie aboutit à la conclusion qu'il ne peut s'agir que d'un dérangement des constellations instables des éléments du corps cellulaire. On peut en déduire qu'un certain degré de désorganisation du plasme est favorable aux divisions cellulaires. En poursuivant et en développant cette conception, les auteurs arrivent à la conception du champ cellulaire de division, définissant les trajectoires des particules élémentaires comme fonction de ses coordonnés relativement aux axes des cellules.相似文献
75.
A trypsin and chymotrypsin inhibitor was partially purified from Bauhenia purpurea seeds and separated from a second inhibitor by Ecteola cellulose chromatography. The factor inhibited bovine trypsin and chymotrypsin as well as pronase trypsin and elastase. It formed a complex with trypsin and with chymotrypsin, but a ternary complex could not be detected. Differences were detected in the effect on trypsin and on chymotrypsin, although one enzyme interfered with the inhibition of the other. The results obtained point to two active centers on the inhibitor for the trypsin and chymotrypsin inhibition such that the one cannot complex with the inhibitor after this inhibitor had complexed with the other. 相似文献
77.
78.
Effect of temperature on the integrity of Bacillus psychrophilus cell walls 总被引:3,自引:1,他引:2 下载免费PDF全文
Cell walls isolated from Bacillus psychrophilus autolyse at temperatures which support growth. At temperatures above the maximum growth temperature (28 C), a nonenzymatic lysis occurs. Removal of autolytic enzyme activity with 10 m LiCl had little effect on the rate or extent of lysis at elevated temperatures (37 and 45 C). Nonenzymatic lysis was characterized chemically by a decrease in the liberation of N-terminal groups, and the effects of pH, Ca(2+), and ethylenediaminetetraacetic acid suggest that ionic linkages are involved in much of the integrity of the cell wall of this psychrophile. The nonenzymatic absorbance decrease at 45 C can be reversed to the extent of 70 to 100% at 0 C. Centrifugation of a heat-lysed wall suspension separated a soluble protein component which is required for low-temperature reaggregation. Preliminary evidence indicates the insoluble residue which remains after temperature-mediated lysis is primarily peptidoglycan. 相似文献
79.
80.
Zhen Li Shengfan Wu Jie Zhang Ka Chun Lee Hang Lei Francis Lin Zilong Wang Zonglong Zhu Alex K. Y. Jen 《Liver Transplantation》2020,10(18)
Perovskite‐organic tandem solar cells are attracting more attention due to their potential for highly efficient and flexible photovoltaic device. In this work, efficient perovskite‐organic monolithic tandem solar cells integrating the wide bandgap perovskite (1.74 eV) and low bandgap organic active PBDB‐T:SN6IC‐4F (1.30 eV) layer, which serve as the top and bottom subcell, respectively, are developed. The resulting perovskite‐organic tandem solar cells with passivated wide‐bandgap perovskite show a remarkable power conversion efficiency (PCE) of 15.13%, with an open‐circuit voltage (Voc) of 1.85 V, a short‐circuit photocurrent (Jsc) of 11.52 mA cm?2, and a fill factor (FF) of 70.98%. Thanks to the advantages of low temperature fabrication processes and the flexibility properties of the device, a flexible tandem solar cell which obtain a PCE of 13.61%, with Voc of 1.80 V, Jsc of 11.07 mA cm?2, and FF of 68.31% is fabricated. Moreover, to demonstrate the achieved high Voc in the tandem solar cells for potential applications, a photovoltaic (PV)‐driven electrolysis system combing the tandem solar cell and water splitting electrocatalysis is assembled. The integrated device demonstrates a solar‐to‐hydrogen efficiency of 12.30% and 11.21% for rigid, and flexible perovskite‐organic tandem solar cell based PV‐driven electrolysis systems, respectively. 相似文献