title: Balanced macromolecular biosynthesis in "protoplasts" of Streptococcus faecalis.
abstract: 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.
mesh_terms: D000643:Ammonium Chloride; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002247:Carbon Isotopes; D003470:Culture Media; D004269:DNA, Bacterial / Q000096:biosynthesis*; D003720:Densitometry; D013293:Enterococcus faecalis / Q000254:growth & development / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism; D009113:Muramidase; D009996:Osmotic Fragility; D011523:Protoplasts / Q000254:growth & development / Q000378:metabolism*; D012329:RNA, Bacterial / Q000096:biosynthesis*; D013395:Sucrose; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014498:Uracil / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002247:Carbon Isotopes; D003470:Culture Media; D004269:DNA, Bacterial; D012329:RNA, Bacterial; D000643:Ammonium Chloride; D014316:Tritium; D014498:Uracil; D013395:Sucrose; D009113:Muramidase; D007930:Leucine; D013936:Thymidine