| Abstract |
Induction conditions for autolysis and autoplast formation of thermophilic Clostridium thermohydrosulfuricum were studied. The cells in the initial exponential growth phase were well autolysed in Tris-HCl buffer or inorganic buffers containing univalents, such as K^+ and Na^+, and chemicals such as cysteine-HCl, sorbitol and glycerol. Meanwhile, autolysis induction was slightly inhibited by divalents, such as Mg^2+, Mn^2+, Ca^2+, Ni^2+, and strongly by divalents, such as Fe^2+, Cu^2+ and citric acid. The autolysis was stimulated when the cells were grown in the medium containing ampicillin that inhibites cell wall synthesis, meanwhile, it was slightly inhibited by nucleic acids and protein synthesis inhibitors. The optimal pH and temperature for the induction of autolysis were 7.5 and 60℃, respectively. On the other hand, the cells were autoplasted without lysozyme treatment during autolysis due to the stabilization of protoplasmic membrane in the presence of divalents such as Mg^2+, Ca^2+, Mn^2+ and Ni^2+. Autoplast formation was mostly induced at 37℃ in 50mM Tris-HCl buffer (pH 7.5) containing 20 mM MgCl_2 and 0.3 M glycerol, and in the late exponential growth phase growing cell. |
