Shift-down in growth rate rather than high cell density induces toxic shock syndrome toxin-1 gene expression in Staphylococcus aureus.
A luciferase-based reporter system for the expression of the toxic shock syndrome toxin-1 gene (tst) of Staphylococcus aureus FRI 1187 was used in continuous culture to determine whether high cell density on transient shift-down or shift-up of specific growth rate (mu) induced expression of tst. Little expression occurred at steady state at a low dilution rate (D) and in a transient period of increasing mu. However, a rapid and approximately 130-fold increase in expression occurred during a transient shift-down of mu. These findings suggest reduction of mu is a key element in the control of tst expression.
Timmins
B S
BS
Skin Research Centre, School of Biochemistry and Molecular Biology, Leeds University, UK.
Holland
K T
KT
D000942:Antigens, Bacterial / Q000235:genetics*; D001427:Bacterial Toxins; D015169:Colony Count, Microbial; D004768:Enterotoxins / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter / Q000235:genetics; D008156:Luciferases; D013211:Staphylococcus aureus / Q000235:genetics* / Q000254:growth & development* / Q000276:immunology / Q000472:pathogenicity; D018089:Superantigens; D013997:Time Factors; D014774:Virulence
D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D004768:Enterotoxins; D018089:Superantigens; C030107:enterotoxin F, Staphylococcal; D008156:Luciferases