Growth-phase associated changes in the reproductive capacity, intracellular polyamines, and antilysozyme activity in Escherichia coli batch culture

Growth-phase associated changes in and relationships between the specific g rowth rate (mu) characterizing the reproductive capacity of the cells, the contents of intracellular biogenic polyamines (BPA), such as putrescine (P) , cadaverine (C), and spermidine (S), and antilysozyme activity (ALA) were studied in 37 strains of Escherichia coil grown in batch culture on solid m edium. A decrease in mu upon the transition of the culture to the stationar y growth phase was accompanied by a decrease in the pool of free BPA, mainl y P and C, and by the appearance of ALA. The interrelations between the par ameters studied were described as a complex of direct and negative correlat ions; the combination of low initial P and C contents, reduced P/S and C/S ratios, and a high level of ALA was designated as a factor of slight inhibi tion of E. coil reproduction. It is argued that BPA and ALA are integrated in a system controlling both the metabolism and stability of peptidoglycan in E. coil.