guanosine-tetraphosphate and Autolysis

The soluble lytic transglycosylase (Slt) of Escherichia coli is known to be a powerful murein hydrolase in vitro. It is shown here to act as an autolysin in vivo as well. Rapid autolysis of Slt overproducing cells was induced by protein biosynthesis inhibitors, which also block the fomration of guanosine-5'-diphosphate-3'-diphosphate (ppGpp). When amino acid starvation was used to inhibit protein synthesis, autolysis was suppressed in relA+ but not in relA- cells. These findings indicate that the stringent control modulates the enzymatic activity of the soluble lytic transglycosylase in vivo.

Topics: Amino Acids; Anti-Bacterial Agents; Autolysis; Escherichia coli; Glycosyltransferases; Guanosine Tetraphosphate; N-Acetylmuramoyl-L-alanine Amidase; Protein Synthesis Inhibitors; Solubility; Transferases