[Comparative study of E. coli strains producing amino acids].

Transduction of the locus of stability to high threonine concentrations (Thrr) into E. coli str M1 and C600 resulted in enhancements of the amino acid production and retardation of the culture development. Besides the mutation caused increase of the specific activity of glutamate synthase, aspartate kinase and homoserine dehydrogenase. The cells of the mutant strains had poorly developed walls and were smaller than those of the parent strains.