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Biomedical subjects

E F Brunngraber

Publications and source records attributed to E F Brunngraber.

8 recordsLinked to original sources
PubMed1977

Action of nucleotide phosphotransferase of Escherichia coli on nicotinamide riboside and nicotinamide mononucleotide.

The action of the nucleotide phosphotransferase of Escherichia coli on nicotinamide riboside and on its 5'-phosphate results in the addition of one phosphate moiety to each of the substrates. Although the proof is not conclusive, it is likely that the phosphate group is transferred to the 3'-hydroxyl of the ribose. This is in contrast to the behavior of the enzyme toward NAD in which only the adenylic acid portion is phosphorylated enzymically.

Chemical Phenomena↗
PubMed1977

Nucleotide phosphotransferase of Escherichia coli: purification by affinity chromatography.

Improved extraction and purification procedures permit the isolation from Escherichia coli W cells of much larger quantities and of more highly purified preparations of nucleotide phosphotransferase. Of various affinity resins tested for efficiency of purification, columns of agarose/5'-AMP (AGAMP), type 3, proved the best. In this way a 300- to 450-fold purification of the enzyme was achieved in a few steps. The enzyme, which, as reported before, transfers organically bound phosphate to the 2' or 3' hydroxyls of nucleosides and nucleotides, was tested in its behavior toward a series of ribonucleosidonucleotides, namely, CpC, ApA, CpA, and ApC. All were phosphate acceptors, but a detailed comparative study of adenosine and cytidine, 5'-AMP and 5'-CMP, and ApA and ApC revealed peculiar specificities in the relative distribution of the phosphorylated products.

Chromatography, Affinity↗
PubMed1970

Transferase from Escherichia coli effecting low-energy phosphate transfer to nucleosides and nucleotides.

This communication describes the partial purification of an enzyme in Escherichia coli that is capable of a low-energy transfer of organically bound phosphate to nucleosides, nucleoside 5'-phosphates, and deoxyribonucleoside 5'-triphosphates. With the exception of adenosine, the nucleosides give rise almost exclusively to 2'- and 3'-nucleotides. Thymidine and its derivatives are the best acceptors of phosphate groups. Since 5'-nucleotides are converted in high yields to the nucleoside 3',5'- or 2',5'-diphosphates, the enzyme may be regarded as a nucleotide phosphotransferase. In the ribonucleotide series, the aglycone affects the relative amounts of 2' and 3' derivatives. The noteworthy formation of nucleoside tetraphosphates suggests several regulatory functions of this enzyme which are discussed briefly.

Chromatography, DEAE-Cellulose↗