[Intracellular organisation of bacteriophage tail-like bacteriocins of group A in Serratia marcescens (author's transl)].

The biosynthesis of a phage tail-like Bacteriocin by cells of the group A-bacteriocinogenic (bA+) Serratia marcescens strain no. 16 after induction with mitomycin C (MC) was examined electron-microscopically. This bacteriocin (total length 117 nm) consists of a hollow core and a contractile sheath. At 60 min following induction, rod-like bacteriocin-particles were identifiable in ultrathin sections. The particles were found to comprise three morphologically different forms of aggregation: 1. hexagonal inclusions, 2. contiguous, band-like particles, and 3. staples of superimposed layers of bacteriocin particles. At 120 min after induction bA+ cells revealed maximally 450 bacteriocin particles. Similarly, the phage tail particles could be demonstrated with the "in situ lysis technique" at 60 min following induction. Occasionally, phage heads were demonstrable, but in no instance were complete phage particles discenible. Dividing cells of the bA+ strain of S. marcescens maintained their rod-form following induction with MC until intracellular phage tail bacteriocin particles were seen. However, at 120 min after induction, the swollen, sphaeroplast-like cells lysed, an event that could be correlated with fine structural alterations of the cell wall.