Uniformly C-13 labeled glucose was fed to a lactic acid bacterium growing on a defined medium supplemented with all proteinogenic amino acids except glutamate. Aspartate stemming from the protein pool and from the extracellular medium was enriched with C-13 disclosing a substantial de novo biosynthesis of this amino acid simultaneous to its uptake from the growth medium and a rapid exchange flux of aspartate over the cellular membrane. Phenylalanine, alanine, and threonine were also synthesized de novo in spite of their presence in the growth medium.
|Journal||Biotechnology and Bioengineering|
|Publication status||Published - 2002|
Jensen, N. B. S., Christensen, B., Nielsen, J., & Villadsen, J. (2002). The simultaneous biosynthesis and uptake of amino acids by Lactococcus lactis studied by C-13-labeling experiments. Biotechnology and Bioengineering, 78(1), 11-16.