Roth G S, Shockman G D, Daneo-Moore L
J Bacteriol. 1971 Mar;105(3):710-7. doi: 10.1128/jb.105.3.710-717.1971.
Osmotically fragile forms of Streptococcus faecalis 9790 were grown in 0.5 m sucrose- or 0.5 m NH(4)Cl-stabilized medium. The "protoplast" cultures exhibit an average growth rate constant of 0.66 to 0.94 mass doublings/hr. In a variety of experiments, turbidity and the net content of protein, ribonucleic acid (RNA) and deoxyribonucleic acid increase at the same rate, indicating balanced macromolecular biosynthesis. A total of two to three mass doublings was obtained, with no evidence of cell division. After osmotic shock, "protoplast" cultures released 93 to 94% of their RNA content in a form not sedimentable at 12,800 x g for 15 min, in contrast to streptococci, which released 7% of their RNA content after the same treatment.
粪肠球菌9790的渗透脆性形态在0.5m蔗糖或0.5m氯化铵稳定的培养基中生长。“原生质体”培养物的平均生长速率常数为每小时0.66至0.94次质量加倍。在各种实验中，浊度以及蛋白质、核糖核酸（RNA）和脱氧核糖核酸的净含量以相同速率增加，表明大分子生物合成是平衡的。总共获得了两到三次质量加倍，没有细胞分裂的迹象。渗透休克后，“原生质体”培养物以在12,800×g下15分钟不可沉淀的形式释放其RNA含量的93%至94%，相比之下，链球菌在相同处理后释放其RNA含量的7%。
