title: Use of resistant mutants to study the interaction of triton X-100 with Staphylococcus aureus.
abstract: Staphylococcus aureus mutants resistant to the nonionic detergent Triton X-100, isolated from the wild-type strain H and the autolysin-deficient strain RUS3, could grow and divide in broth containing 5% (vol/vol) Triton X-100, while growth of the parental strains was markedly inhibited above the critical micellar concentration (0.02%) of the detergent. Growth-inhibitory concentrations of Triton X-100 killed wild-type cells without demonstrable cellular lysis. Triton X-100 stimulated autolysin activity of S. aureus cells under nongrowing conditions, and this lytic response was markedly reduced in energy-poisoned cells. In contrast, the detergent had no effect on the activity of autolysins in cell-free systems, and growth in the presence of Triton X-100 did not alter either the cellular autolysin activity or the susceptibility of cell walls to exogenous lytic enzymes. Treatment with either Triton X-100 or penicillin G in the growth medium stimulated release of predominantly acylated intracellular lipoteichoic acid and sensitized staphylococci to Triton X-100-induced autolysis. There was no significant difference in the cell wall and membrane compositions or Triton X-100 binding between the parental strains and the resistant mutants. The resistant mutant TXR1, derived from S. aureus H, had a higher level of L-alpha-glycerophosphate dehydrogenase activity, and its oxygen uptake was more resistant to inhibition by a submicellar concentration (0.008%) of Triton X-100. Growth in the presence of subinhibitory concentrations of Triton X-100 rendered S. aureus H cells phenotypically resistant to the detergent and greatly stimulated the level of oxygen uptake. Membranes isolated from such cells exhibited enhanced activity of the respiratory enzymes succinic dehydrogenase and L-alpha-glycerophosphate dehydrogenase.
authors.forename: D
authors.initials: D
authors.lastname: Raychaudhuri
authors.forename: A N
authors.initials: AN
authors.lastname: Chatterjee
mesh_terms: D001386:Azides / Q000494:pharmacology; D002473:Cell Wall / Q000187:drug effects; D002850:Chromatography, Gel; D003470:Culture Media; D050356:Lipid Metabolism; D008070:Lipopolysaccharides; D009154:Mutation; D009238:N-Acetylmuramoyl-L-alanine Amidase / Q000172:deficiency; D017830:Octoxynol; D010101:Oxygen Consumption / Q000187:drug effects; D010400:Penicillin G / Q000494:pharmacology; D010403:Penicillin Resistance; D010539:Permeability; D010712:Phosphatidic Acids / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D011092:Polyethylene Glycols / Q000494:pharmacology*; D019810:Sodium Azide; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D013682:Teichoic Acids / Q000378:metabolism
chemical_list: D001386:Azides; D003470:Culture Media; D008070:Lipopolysaccharides; D010712:Phosphatidic Acids; D010743:Phospholipids; D013682:Teichoic Acids; D011092:Polyethylene Glycols; C009900:lipoteichoic acid; D017830:Octoxynol; D019810:Sodium Azide; D009238:N-Acetylmuramoyl-L-alanine Amidase; D010400:Penicillin G