Function
Alpha-toxin has been shown to play a role in pathogenesis of disease, as hla knockout strains show reductions in invasiveness and virulence. Interestingly, the dosage of toxin can result in two different modes of activity. Low concentrations of toxin bind to specific, but unidentified, cell surface receptors and form the heptameric pores. This pore allows the exchange of monovalent ions, resulting in DNA fragmentation and eventually apoptosis. Higher concentrations result in the toxin absorbing nonspecifically to the lipid bilayer and forming large, Ca2+ permissive pores. This in turn results in massive necrosis and other secondary cellular reactions triggered by the uncontrolled Ca2+ influx.
Read more about this topic: Staphylococcus Aureus Alpha Toxin
Famous quotes containing the word function:
“Morality and its victim, the mother—what a terrible picture! Is there indeed anything more terrible, more criminal, than our glorified sacred function of motherhood?”
—Emma Goldman (1869–1940)
“It is not the function of our Government to keep the citizen from falling into error; it is the function of the citizen to keep the Government from falling into error.”
—Robert H. [Houghwout] Jackson (1892–1954)
“The information links are like nerves that pervade and help to animate the human organism. The sensors and monitors are analogous to the human senses that put us in touch with the world. Data bases correspond to memory; the information processors perform the function of human reasoning and comprehension. Once the postmodern infrastructure is reasonably integrated, it will greatly exceed human intelligence in reach, acuity, capacity, and precision.”
—Albert Borgman, U.S. educator, author. Crossing the Postmodern Divide, ch. 4, University of Chicago Press (1992)