Biosynthetic l‐Threonine Deaminase as the Origin of l‐Serine Sensitivity of Escherichia coli

Abstract

Bacteria of some Escherichia coli strains are inhibited temporarily by l‐serine in resuming growth at a minimal to minimal medium transfer when this amino acid is present in high enough concentrations in the new medium. The serine effect can be counteracted by l‐threonine in a competitive manner and by isoleucine and by 2‐oxobutyrate in a noncompetitive manner. It is demonstrated that l‐threonine deamination by the biosynthetic l‐threonine deaminase is inhibited in the presence of l‐serine. Copyright © 1971, Wiley Blackwell. All rights reserved