Pyridine nucleotide cycle of Salmonella typhimurium: in vitro demonstration of nicotinamide mononucleotide deamidase and characterization of pnuA mutants defective in nicotinamide mononucleotide transport

Pyridine nucleotide cycle of Salmonella typhimurium: regulation of nicotinic acid phosphoribosyltransferase and nicotinamide deamidase.

Nicotinic acid phosphoribosyl transferase (NAPRTase) and nicotinamide deamidase activities from Salmonella typhimurium were examined regarding their regulation by either feedback inhibition or repression mechanisms. The results indicate that neither enzyme is subject to feedback inhbition. Nicotinamide deamidase does not appear to be under repression control. NAPRTase, however, is repressed whe...

Enzymatic synthesis of polymers containing nicotinamide mononucleotide.

Nicotinamide mononucleoside 5'-diphosphate in its reduced form is an excellent substrate for polynucleotide phosphorylase from Micrococcus luteus both in de novo polymerization reactions and in primer extension reactions. The oxidized form of the diphosphate is a much less efficient substrate; it can be used to extend primers but does not oligomerize in the absence of a primer. The cyanide addu...

Nicotinamide mononucleotide pyrophosphorylase activity in animal tissues.

An enzyme which catalyzes the formation of nicotinamide mononucleotide in the presence of nicotinamide, S-phosphoribosylpyrophosphate, adenosine triphosphate, and Mgff has been purified from rat liver. The reaction is highly specific for ATP and is not substituted for by a variety of nucleotides. Enzymic activity has been found in all of the tissues studied, and in the crude homogenate it is ap...

Characterization of nicotinamide mononucleotide adenylyltransferase from thermophilic archaea.

The enzyme nicotinamide mononucleotide (NMN) adenylyltransferase (EC 2.7.7.1) catalyzes the synthesis of NAD+ and nicotinic acid adenine dinucleotide. It has been purified to homogeneity from cellular extracts of the thermophilic archaeon Sulfolobus solfataricus. Through a database search, a highly significant match was found between its N-terminal sequence and a hypothetical protein coded by t...

Nicotinamide mononucleotide adenylyltransferase of pig-liver nuclei. The effects of nicotinamide mononucleotide concentration and pH on dinucleotide synthesis.