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141.
Friedrich von der Haar 《Biochemical and biophysical research communications》1976,70(3):1009-1013
Proteins can be precipitated onto the surface of unsubstituted agarose at an ammonium sulfate concentration about 10% lower than needed for precipitation out of solution. The protein is fractionally redissolved by developing agarose columns with a linear, decreasing gradient of ammonium sulfate. The method is characterized by high reproducibility, good purification factors and high recovery of enzymatic activity. As an example the method is applied to the purification of aminoacyl-tRNA synthetases (E.C. 6.1.1.-) specific for phenylalanine, isoleucine and valine. 相似文献
142.
Friedrich Brock 《Development genes and evolution》1927,112(1):204-238
Ohne ZusammenfassungHerr C.Vrieslander zeichnete in uneigennütziger Weise alle Abbildungen dieser Arbeit, welche durch Herrn Dr.Schulz von der Kulturabteilung der Universum-Filmgesellschaft nach meinen Angaben kinematographiert worden waren. 相似文献
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Staphylococcus aureus Lpl protein triggers human host cell invasion via activation of Hsp90 receptor
Paula M. Tribelli Arif Luqman Minh‐Thu Nguyen Johannes Madlung Sook‐Ha Fan Boris Macek Peter Sass Katharina Bitschar Birgit Schittek Dorothee Kretschmer Friedrich Gtz 《Cellular microbiology》2020,22(1)
Staphylococcus aureus is a facultative intracellular pathogen. Recently, it has been shown that the protein part of the lipoprotein‐like lipoproteins (Lpls), encoded by the lpl cluster comprising of 10 lpls paralogue genes, increases pathogenicity, delays the G2/M phase transition, and also triggers host cell invasion. Here, we show that a recombinant Lpl1 protein without the lipid moiety binds directly to the isoforms of the human heat shock proteins Hsp90α and Hsp90ß. Synthetic peptides covering the Lpl1 sequence caused a twofold to fivefold increase of S. aureus invasion in HaCaT cells. Antibodies against Hsp90 decrease S. aureus invasion in HaCaT cells and in primary human keratinocytes. Additionally, inhibition of ATPase function of Hsp90 or silencing Hsp90α expression by siRNA also decreased the S. aureus invasion in HaCaT cells. Although the Hsp90ß is constitutively expressed, the Hsp90α isoform is heat‐inducible and appears to play a major role in Lpl1 interaction. Pre‐incubation of HaCaT cells at 39°C increased both the Hsp90α expression and S. aureus invasion. Lpl1‐Hsp90 interaction induces F‐actin formation, thus, triggering an endocytosis‐like internalisation. Here, we uncovered a new host cell invasion principle on the basis of Lpl‐Hsp90 interaction. 相似文献
150.
Bojana Radoman Clemens Grünwald-Gruber Bernhard Schmelzer Domen Zavec Brigitte Gasser Friedrich Altmann Diethard Mattanovich 《Biotechnology journal》2021,16(3):2000266
The methylotrophic yeast Pichia pastoris is known as an efficient host for the production of heterologous proteins. While N-linked protein glycosylation is well characterized in P. pastoris there is less knowledge of the patterns of O-glycosylation. O-glycans produced by P. pastoris consist of short linear mannose chains, which in the case of recombinant biopharmaceuticals can trigger an immune response in humans. This study aims to reveal the influence of different cultivation strategies on O-mannosylation profiles in P. pastoris. Sixteen different model proteins, produced by different P. pastoris strains, are analyzed for their O-glycosylation profile. Based on the obtained data, human serum albumin (HSA) is chosen to be produced in fast and slow growth fed batch fermentations by using common promoters, PGAP and PAOX1. After purification and protein digestion, glycopeptides are analyzed by LC/ESI-MS. In the samples expressed with PGAP it is found that the degree of glycosylation is slightly higher when a slow growth rate is used, regardless of the efficiency of the producing strain. The highest glycosylation intensity is observed in HSA produced with PAOX1. The results indicate that the O-glycosylation level is markedly higher when the protein is produced in a methanol-based expression system. 相似文献