Studies on Regeneration Media forBacillus subtilisProtoplasts

Abstract
Bacillus subtilis protoplasts regenerate on media containing horse serum, bovine serum or gelatin. These compounds could be replaced by polyvinyl pyrrolidone or dextran, and a medium which contained 30 g polyvinyl pyrrolidone and 20 mg casamino acids per liter with chemically defined ingredients was especially useful for selection of prototrophs, e.g., by protoplast fusion. Polyvinyl pyrrolidone and other plasma expanders stimulated protoplast division in liquid media and improved protoplast survival on agar media.