title: Stabilization of glucose-starved Escherichia coli K12 and Salmonella typhimurium LT2 by peptidase-deficient mutants.
abstract: Escherichia coli K12 and Salmonella typhimurium LT2 cells were stabilized during carbon starvation in the presence of peptidase-deficient mutant strains. The rate of loss of viability of the wild-type S. typhimurium strain was decreased an average of 2-fold, and the rate for the wild-type E. coli strain was decreased about 2.3-fold, when either was starved in the presence of the multiply peptidase-deficient S. typhimurium strain TN852; other peptidase-deficient strains exhibited similar stabilizing effects. Starving wild-type S. typhimurium LT2 cells utilized peptides excreted by the starving peptidase-deficient cells for protein synthesis, and, to a lesser extent, as respiratory substrates. Provision of free amino acids in steady-state levels to starving E. coli K12 cells in a cell recycle apparatus had a stabilizing effect similar to that of mixing with peptidase-deficient cells.
mesh_terms: D003470:Culture Media; D004926:Escherichia coli / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D009154:Mutation; D010447:Peptide Hydrolases / Q000172:deficiency*; D012486:Salmonella typhimurium / Q000201:enzymology / Q000378:metabolism*; D013997:Time Factors
chemical_list: D003470:Culture Media; D010447:Peptide Hydrolases; D005947:Glucose