Properties of protoplasts from the thermophile Bacillus coagulans and their significance for genetic studies

Regeneration of protoplasts of Bacillus coagulans was optimized by using low lysozyme concentrations and glycerol as the osmotic support. Protoplasts formed from cells grown at higher temperatures were thermostable and capable of regeneration at 55°C. Transfer of plasmids pAB224 and pUB110, using either whole cells or protoplast transformation was not achieved, despite using a variety of conditions. However, plasmid transfer was achieved by fusion with B. subtilis protoplasts containing plasmid pAB224.