title: Effect of the composition of reversion medium on change of Staphylococcus aureus lysostaphin protoplasts to coccal forms and L-forms.
abstract: The experimental conditions under which protoplasts of Staphylococcus aureus strain MS353 (pCp) are converted to the coccal or L-form were investigated. Protoplasts prepared by treating coccal MS353 (pCp) strain with Lysostaphin formed various types of colonies (coccal form, L-form and mixed types) in about 50% yield when they were plated on reversion (R) medium consisting of 2% brain heart infusion, 0.5M sodium succinate, 0.01% bovine serum albumin, 20 mM MgCl2 and 0.6% agar. The L-form type colonies with a typical fried-egg appearance that developed on the R medium at an early stage gradually reverted to the coccal form through a mixed type stage in which a high density area first appeared in the periphery of the colony and then spread throughout the colony. The use of modified R medium without MgCl2 or R medium in which 0.5M sodium succinate as an osmotic stabilizer was replaced by 7.5% NaCl resulted in marked delay in the appearance of reverted cells. R medium without bovine serum albumin yielded atypical L-form type colonies, which contained masses of coccal cells with very irregular margins. On the other hand, R medium without MgCl2 but with penicillin G supported development of L-form type colonies at high rate (13-15%) from the inoculated protoplasts.
mesh_terms: D003470:Culture Media; D007740:L Forms / Q000166:cytology* / Q000254:growth & development; D008248:Lysostaphin / Q000494:pharmacology*; D008274:Magnesium / Q000378:metabolism; D015636:Magnesium Chloride; D011523:Protoplasts / Q000502:physiology*; D012710:Serum Albumin, Bovine / Q000378:metabolism; D013211:Staphylococcus aureus / Q000166:cytology* / Q000254:growth & development
chemical_list: D003470:Culture Media; D015636:Magnesium Chloride; D012710:Serum Albumin, Bovine; D008248:Lysostaphin; D008274:Magnesium