Enzymes, polynucleotide

The experiments were carried out using Ci4-phosphatidylcholine (PC) vesicles. The biochemical reaction which was planned to occur in the vesicles was the aforementioned RNA polymerisation reaction involving the enzyme polynucleotide phosphorylase (PNPase), which Oparin and co-workers had used many years ago in their work on coacervates. PNPase and added ADP then form oligonucleotides in the vesicles. 

In 1955, Marianne Grunberg-Manago and Severo Ochoa discovered the bacterial enzyme polynucleotide phosphorylase, which in vitro catalyzes the reaction... 

The Chemistry of Nucleic Acid Biosynthesis Describe three properties common to the reactions catalyzed by DNA polymerase, RNA polymerase, reverse transcriptase, and RNA replicase. How is the enzyme polynucleotide phos-phorylase similar to and different from these three enzymes ... 

Growing membrane systems have been used to obtain artificial infrabiological systems. Walde et al. [47] have carried out the synthesis of polyadenylic acid in self-reproducing vesicles [48], in which the enzyme polynucleotide phosphorylase carried out the synthesis of poly-A, and membrane vesicle multiplication was due to the hydrolysis of externally provided oleic anhydride to oleic acid. The snag is that the enzyme component is not auto-catalytic. Enzymatic RNA replication in vesicles [49] suffers from the same problem. It is also not known whether redistribution of the entrapped enzymes into newly formed vesicles occurs or not. An affirmative answer would be evidence for vesicle reproduction by fission. 

Freschauf GK, Karimi-Busheri F, Ulaczyk-Lesanko A et al (2009) Identification of a small molecule inhibitor of the human DNA repair enzyme polynucleotide kinase/phosphatase. Cancer Res 69 7739-7746... 

Fig. 6.9. labelling in the Maxam-Gilbert method The 5 -end reacts with [y- P]-ATP nnder catalysis of the enzyme polynucleotide kinase. If a phosphate group is present at the 5 -end, this must be removed first by treatment with alkaline phosphatase. 

Immobilization of enzymes, polynucleotide, and antibodies for sensing or catalysis... 

Synthetic polynucleotide complexes have been shown to be effective immune response modulators in animals and man (Braun et al. 1971, Johnson 1979). The polynucleotides are formed foUowing the action of an enzyme, polynucleotide phosphor-ylase on the synthetic mononucleotide diphosphates. Complexing takes place following the mixing of polymers composed of opposite base pairs. Two have been utilised, polyinosinic acid complexed with polycytidylic acid (poly I poly C) and polyad-enylic acid complexed with polyuridylic acid (poly A poly U). The single strands mononucleotides are ineffective. 

They named the enzyme polynucleotide phosphorylase. On the basis of this intelligence, we switched substrates from P-ATP to P-ADP. As a result, our activity increased many fold and we succeeded in purifying polynucleotide phosphorylase from E. coli instead of discovering RNA polymerase. What a blunder ... 

Remarkable progress has been made in the once formidable field of nucleic acid synthesis, since the discovery in 1955 of the enzyme polynucleotide phosphorylase in Azotc xicter vineUmdii (191, 192). The enzyme catalyzes the following reversible reaction ... 

A new generation of a directional, ligation-independent cloning strategy based on the 3 — 5 -exonuclease activity of T4 DNA Pol now provides the most efficient cloning methods which circumvent the use of restriction enzymes, polynucleotide kinase, phosphatase, or DNA ligase (see Fig. 6.3). 

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