Results 191 to 200 of about 6,571 (231)

Human polynucleotide phosphorylase: location matters

Trends in Cell Biology, 2007
Human polynucleotide phosphorylase (hPNPase) is an RNA-processing enzyme induced in response to type I interferons and during terminal differentiation and cellular senescence. hPNPase was thought to contribute to cellular senescence through its RNA-degrading activity in the cytosol; however, recent studies show that hPNPase localizes to the ...
Hsiao-Wen, Chen, Carla M, Koehler, Michael A, Teitell   +2 more
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Conserved domains in polynucleotide phosphorylase among eubacteria

Biochimie, 2005
Polynucleotide phosphorylase (PNPase) is a polynucleotide nucleotidyl transferase (E. C. 2.7.7.8) that is involved in mRNA degradation in prokaryotes. PNPase structure analysis has been performed in Streptomyces antibioticus; this revealed the presence of five domains: two ribonuclease PH (RPH)-like (pnp1 and pnp2), one alpha helical, one KH, and one ...
Rosa María, Bermúdez-Cruz, Fernando, Fernández-Ramírez, Fernando, Ramírez, Luis, Kameyama-Kawabe, Cecilia, Montañez   +4 more
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Activation of Polynucleotide Phosphorylase by Salts

Nature, 1957
IN the course of purification studies of polynucleotide phosphorylase (polyase) from M. lysodeikticus we have on several occasions noticed that, after dialysis against buffers at low ionic strength or distilled water, considerable loss of enzyme activity occurred.
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Mechanism of polynucleotide phosphorylase

Biochemistry, 1989
The de novo polymerization of RNA initiated by polynucleotide phosphorylase from nucleoside diphosphates was examined. End group analysis performed under conditions designed to specifically end label the polymer revealed no evidence for a 5'-pyrophosphate-terminated polymer.
M, Sulewski, S P, Marchese-Ragona, K A, Johnson, S J, Benkovic   +3 more
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Photometric Assay for Polynucleotide Phosphorylase

Analytical Biochemistry, 1999
Polynucleotide phosphorylase (PNPase) is a prokaryotic enzyme that catalyzes phosphorolysis of polynucleotides with release of NDPs. It is also believed to play a key role in turnover of prokaryotic transcripts, thus regulating gene expression. At the moment, only radioisotopic methods are available for assaying PNPase in crude extracts; these involve ...
L, Fontanella, S, Pozzuolo, A, Costanzo, R, Favaro, G, Dehò, P, Tortora   +5 more
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Polynucleotide phosphorylase from plant cells

Plant Cell Reports, 1984
The isolation of polynucleotide phosphorylase (EC 2. 7. 7. 8) from suspension cultured plant cells of parsley (Petroselinum sativum) and from tomato seedlings (Lycopersicon esculentum) is described. The procedure includes an ultracentrifugation step, a glycerol density gradient centrifugation and preparative gel electrophoresis under nondenaturing ...
E, Schumacher-Wittkopf, G, Richter, S, Schulze   +2 more
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Polynucleotide Phosphorylase and the T3SS

2007
Low temperatures as well as encounters with host phagocytes are two stresses that have been relatively well studied in many species of bacteria. The exoribonuclease polynucleotide phosphorylase (PNPase) has previously been shown to be required by several species of bacteria, including Yersinia, for low-temperature growth. We have shown that PNPase also
Jason A, Rosenzweig, Kurt, Schesser
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The origin of polynucleotide phosphorylase domains

Molecular Phylogenetics and Evolution, 2004
In this report, we document the presence of polynucleotide phosphorylase (PNPase) in the animal eukaryotes. These proteins contain several domains, including 2 RNase PH domains (PNPase 1 and PNPase 2) which are closely related functionally and in sequence similarity to ribonuclease PH (RPH) protein.
Magdalena, Leszczyniecka, Rob, DeSalle, Dong-Chul, Kang, Paul B, Fisher   +3 more
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Enzymic synthesis of polynucleotides I. polynucleotide phosphorylase of Azotobacter vinelandii

Biochimica et Biophysica Acta, 1956
The isolation, partial purification and some properties of polynucleotide phosphorylase of Azotobacter vinelandii are described. The enzyme catalyzes the synthesis of highly polymerized ribonucleic acid-like polynucleotides from 5′-nucleoside diphosphates with release of orthophosphate. The reaction requires magnesium ions and is reversible.
M, GRUNBERG-MANAGO, P J, ORTIZ, S, OCHOA
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Model for the elongation of polynucleotide chains by polynucleotide phosphorylase

Journal of Molecular Biology, 1970
Abstract The experiments described in this paper were designed to elucidate the mechanism of elongation of a polynucleotide chain catalysed by polynucleotide phosphorylase. The problem has been approached in three different ways, essentially: (1) examination of the size distribution of the end products isolated during the course of the reaction; (2 ...
M N, Thang, R A, Harvey, M, Grunberg-Manago   +2 more
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