title: Morphological and physiological study of autolytic-defective Streptococcus faecium strains.
abstract: Three autolytic-defective mutants of Streptococcus faecium (S. faecalis ATCC 9790) were isolated. All three autolytic-defective mutants exhibited the following properties relative to the parental strain: (i) slower growth rates, especially in chemically defined medium; (ii) decreased rates of cellular autolysis and increased survival after exposure to antibiotics which block cell wall biosynthesis; (iii) decreased rates of cellular autolysis when treated with detergents, suspended in autolysis buffers, or grown in medium lacking essential cell wall precursors; (iv) a reduction in the total level of cellular autolytic enzyme (active plus latent forms of the enzyme); (v) an increased ratio of latent to active forms of autolysin; and (vi) increased levels of both cellular lipoteichoic acid and lipids.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001433:Bacteriolysis; D002473:Cell Wall / Q000187:drug effects; D003470:Culture Media; D013293:Enterococcus faecalis / Q000235:genetics* / Q000502:physiology / Q000648:ultrastructure; D006867:Hydrolases / Q000235:genetics*; D008055:Lipids / Q000032:analysis; D009154:Mutation; D013501:Surface-Active Agents / Q000494:pharmacology; D013682:Teichoic Acids / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D008055:Lipids; D013501:Surface-Active Agents; D013682:Teichoic Acids; D006867:Hydrolases