Cell division of penicillin-induced filaments ofEscherichia coli

Reversion of cell division of penicillin-induced filamentous forms ofEscherichia coli was studied from the aspect of the function of proteosynthesis in reversion and the renewal of intact mucopeptide, and from the aspect of the function of mucopeptide in reversion. Mucopeptide renewal is an, essential condition for the initiation of reversion. If proteosynthesis is inhibited immediately after removing the penicillin, the mucopeptide is not renewed. If inhibition is delayed, it is renewed in amounts proportional to the interval of proteosynthesis. Mucopeptide renewal is probably not sufficient for completing reversion under conditions of inhibition of proteosynthesis, however. The possible existence of a protein involved in cytokinesis, whose presence or activity is determined by an intact mucopeptide structure, is discussed. From direct observation of the formation of microcolonies from filaments, we found that septa which are formed later during normal division in the absence of penicillin were formed earlier during reversion.