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Eugen Fischer 《Molecular genetics and genomics : MGG》1913,10(1):280-280
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986.
Albert Fischer 《Protoplasma》1932,14(1):474-485
Ohne Zusammenfassung 相似文献
987.
Ohne Zusammenfassung 相似文献
988.
David L. Brautigam Balwant S. Khatra Thomas R. Soderling Edmond H. Fischer 《Archives of biochemistry and biophysics》1982,219(1):228-235
An Mn2+-activated phosphoprotein phosphatase of Mr = 80,000 from rabbit muscle catalyzes the dephosphorylation of skeletal muscle proteins that are phosphorylated by either phosphorylase kinase or cAMP-dependent protein kinase. Phosphorylase or glycogen synthase labeled by phosphorylase kinase at seryl residues 14 or 7, respectively, are both dephosphorylated by the phosphatase. Phosphorylase a and glycogen synthase compete with one another for the phosphatase. The phosphatase discriminates between different sites labeled by the cAMP-dependent protein kinase: glycogen synthase phosphorylated either to 1.0 or 1.8 mol phosphate/mol, or phosphorylase kinase phosphorylated on its β-subunit serve as substrates for the phosphatase, but the phosphorylase kinase α-subunit, the phosphorylated phosphatase inhibitor 1, or casein do not. Histone fraction IIA, phosphorylated by the catalytic subunit, was a poor substrate even at a concentration of 100 μm. Phosphorylation of the α-subunit of phosphorylase kinase had no influence on the kinetics of dephosphorylation of the β-subunit. Thus, the Mr = 80,000 phosphatase meets the functional definition of a protein phosphatase 1 [Cohen, P. (1978) Curr. Top. Cell. Regul.14, 117–196]. Furthermore, from a comparison of the known phosphorylated sites of these proteins, it appears that the phosphatase discriminates between different sites present in the phosphoproteins tested on the basis of the Km values for the reactions. It displays a preferential activity toward proteins with a primary structure wherein basic residues are two positions amino-terminal from the phosphoserine, AgrLysX-YSer(P) or LysArgX-YSer(P), rather and one residue away, ArgArgX-Ser(P). 相似文献
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The Early Devonian Rhynie chert has been critical in documenting early land plant-fungal interactions. However, complex associations involving several fungi that enter into qualitatively different relationships with a single host plant and even interact with one another have not yet been detailed. Here, we studied petrographic thin sections of the Rhynie chert plant Nothia aphylla. Three fungal endophytes (co)occur in prostrate axes of this plant: narrow hyphae producing clusters of small spores; large spherical spores/zoosporangia; and wide aseptate hyphae that form intercellular vesicles in the cortex. Host responses on attack include bulging of infected rhizoids, formation of encasement layers around intracellular hyphae, and separation of infected from uninfected tissues by secondarily thickened cell walls. A complex simultaneous interaction of N. aphylla with three endophytic fungi was discovered. The host responses indicate that some of the mechanisms causing host responses in extant plants were in place 400 million yr ago. Anatomical and life history features of N. aphylla suggest that this plant may have been particularly susceptible to colonization by fungi. 相似文献