The process of L-threonine production using Escherichia coli TRFC was investigated, and the result showed that there was a large amount of acetic acid in the broth. The effects of acetic acid, which is a known inhibitory metabolite in E. coli cultivation, on L-threonine production by recombinant E. coli TRFC were evaluated, and the result indicated that the growth of E. coli TRFC and L-threonin...

L-threonine dehydrogenase (E.C.1.1.1.103) catalyzes the NAD+-dependent transformation of Lthreonine to 2-amino 3-0x0-butyric acid, which spontaneously loses CO2 with the final production of aminoacetone ( 1) The enzyme is present in several microorganisms as well as in the liver of vertebrates (2-6). We studied some properties of the rat liver enzyme, showing that the activity was strongly inhi...

Concerted feedback inhibition of aspartokinase activity from Pseudomonasfluorescens by the combination of L-threonine and r.-lysine, or by L-threonine and L-methionine was freely and rapidly reversible. Inhibition by L-threonine, or by the concerted pairs of amino acids was kinetically “mixed” with respect to L-aspartate and noncompetitive with regard to ATP. In the presence of L-threonine the ...

Concerted feedback inhibition of aspartokinase activity from Pseudomonasfluorescens by the combination of L-threonine and r.-lysine, or by L-threonine and L-methionine was freely and rapidly reversible. Inhibition by L-threonine, or by the concerted pairs of amino acids was kinetically “mixed” with respect to L-aspartate and noncompetitive with regard to ATP. In the presence of L-threonine the ...

Although amino acids can function as signaling molecules in the regulation of many cellular processes, mechanisms surrounding L-threonine involvement in embryonic stem cell (ESC) functions have not been explored. Thus, we investigated the effect of L-threonine on regulation of mouse (m)ESC self-renewal and related signaling pathways. In L-threonine-depleted mESC culture media mRNA of self-renew...

In pigs the extensive threonine utilization by the splanchnic tissues explains the relative inefficiency of dietary threonine conversion for body protein accretion. Two experiments were conducted to estimate the contribution of the portal drained viscera (PDV) and the liver to threonine metabolism and especially catabolism in growing pigs. In the first experiment, four pigs were surgically prep...

L-Threonine dehydrogenase (L-threonine:NAD+ oxidoreductase (EC 1.1.1.103) has been purified to apparent homogeneity from chicken liver mitochondria. The presence of 2-mercaptoethanol and glycerol is necessary for stabilizing the enzyme during purification and storage. The enzyme is a monomer and has Mr approximately equal to 88,000. The pH optimum is 8.6 to 8.7, and the isoelectric point of the...

A mixture of threonine dehydrogenase and aminoacetone synthetase will catalyze the conversion of L-threonine to glycine. The overall reaction likely involves the conversion of L-threonine, NAD+, and CoA to glycine, NADH, and acetyl-CoA. Physical separation of L-threonine dehydrogenase from aminoacetone synthetase results in the formation of aminoacetone and CO2 from their substrates. A physical...