Effect of L-asparagine on growth of Mycobacterium tuberculosis and on utilization of other amino acids.

l-Asparagine controls the utilization of other amino acids by Mycobacterium tuberculosis (H37Ra) in aerated, liquid synthetic media. In a mixture containing asparagine and either l-alanine or l-glutamic acid, amino acid utilization is diphasic, with asparagine being utilized first. Short-term growth rates and cell yields are diminished and mimic those seen with asparagine alone. Catabolite repression is the probable regulatory mechanism responsible for this effect of asparagine. In contrast, in the presence of aspartic acid, asparagine stimulates growth and increases utilization of aspartic acid.