Growth and Division of Protoplasts of Bacillus megaterium and Inhibition of Division by Penicillin

Abstract

Protoplasts of Bacillus megaterium grew well and divided in nutrient broth containing 0.5 M NaCl as the stabilizer. Protoplasts also grew when sucrose or succinate was used instead of NaCl; however, no division phenomena were observed. The sequence of growth and division was similar to the results obtained by McQuillen. Protoplasts enlarged from 1.8 to 3.5 ,u in diameter, and then a small protuberance formed in the enlarged cells. The nodules enlarged until eventually symmetrical dumbbell-shaped bodies were formed, which then separated into two daughter protoplasts having a diameter of about 2.5 ,. Deoxyribonucleic acid and ribonucleic acid were halved during division. Penicillin inhibited the division of protoplasts, though the growth was not influenced by the drug. Membrane-bound amino sugar content was considerably reduced when the cells were grown in the presence of penicillin. These results suggest that organized murein formed on the protoplasts membrane may play an important role in the septation process.

Balanced Macromolecular Biosynthesis in “Protoplasts” of Streptococcus faecalis

“…However, balanced growth has not been unequivocally established for cultures of osmotically fragile cells. On the contrary, many earlier investigations of macromolecular biosynthesis in "protoplast" cultures demonstrated unbalanced (3,5,11) linear, rather than exponential, growth (6), or a lag prior to the onset of growth (5,9). A previous study from this laboratory indicated that "protoplasts" of Streptococcusfaecalik (ATCC 9790) could be obtained by treatment with lysozyme in the presence of 0.5 M sucrose (8).…”

Magnesium‐Stimulated Resynthesis of Osmoresistant Layer by Candida albicans Spheroplasts

“…Organism and cultivation . Candida albicans IFO (0600) was maintained on Sabouraud's glucose (SG) agar slants and successively subcultured twice at 30 various stabilizers (MgSO4, CaCl2, MnSO4, KC1, MgCl2, NaC1 or sucrose) at various concentrations. The plates were incubated at 30 C for 7 hr (preincubation) and then washed twice with water for 15 min each by pouring sterilized water onto the agar layer.…”

“…Recent studies on those osmolabile spherical bodies had thrown much light on the mechanism of their regeneration [10,12,13,16,18,24,26,38,41,42,47,60] and on cellular physiology. On the other hand, studies on the lysis of cell wall structures by these lytic enzymes had provided information on cell wall structures of bacteria and fungi, the mode of action of lytic enzymes and the mechanism of action of antibacterial and antifungal antibiotics [4,11,29,30,31,34,36,39,48,51].…”

Induction and cultivation of a stable L‐form of Bacillus subtilis

“…Bacillus subtilis NCIB 8054, ATCC 6633 was used throughout this study. Protoplasts were induced with the method devised for Bacillus megaterium by Kusaka (1967). During induction, lysozyme (EC 3.2.1.17, Sigma, UK) was used at a final concentration of 2040 units/ml and conversion into spherical protoplasts was monitored with phase and interference contrast microscopy (Reichert-Jung Polyvar Microscope, Austria).…”