%0 Journal Article %A Watanabe, K. %A Takesue, S. %T Preparation of Sphaeroplasts from Lactobacillus casei by Growth with Low Concentration of Benzylpenicillin %D 1973 %J Microbiology, %V 79 %N 1 %P 151-153 %@ 1465-2080 %R https://doi.org/10.1099/00221287-79-1-151 %I Microbiology Society, %X A strain of Lactobacillus casei used for the production of a lactic acid beverage is susceptible to phage infections. Calcium ions were required for the formation of PL-i phage-infected bacteria (Watanabe & Takesue, 1972). Further studies on the role of calcium ions in phage infection required the use of protoplasts or sphaeroplasts of the host bacteria. Early trials using egg-white lysozyme, EDTA or glycine to form sphaeroplasts were unsuccessful. However, a simple procedure to produce sphaeroplasts using a low concentration of benzylpenicillin has been successfully developed and is described here together with information on some factors affecting the stability of the sphaeroplasts. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-79-1-151