Toxic shock protein

S. R. Monday G. A. Bohach, Properties ot Staphylococcus aureus Enterotoxins and Toxic Shock Syndrome Toxin-1. in The Comprehensive Sourcebook of Bacterial Protein Toxins, 2nd ed. J. E. Aiout, J. H. Freer, Eds. Academic Press London, 1999 pp 589-610. 

Boyle et al. (2001) used the Ciphergen SELDI protein chip to analyze the secretion and autoactivation of a cysteine protease (SpeB) from Streptococcus pyogenes that has been implicated in the onset of group A streptococcal infections and may contribute to toxic shock symptoms. SpeB could be detected at 0.75 ng protein in a 30-min assay based upon SELDI-TOF... 

Figure 7.21 The cascade of events in the liver following a toxic dose of paracetamol. Hsp10, Hsp 60 are heat shock proteins, which have a protective function, cyt c is ctyochrome c. TNF-a, EGR-1, and GM-CSF are all genes involved with apoptosis, c-fos, APAF-1, and c-myc are also genes.

The bacterial toxins responsible for toxic shock syndrome are proteins that are classified as superantigens. These proteins bypass some of the steps normally involved in antigen-mediated immune response, thereby activating 5 to 30% of the T cell population, compared to 0.01 to 0.1% activated by conventional antigens. The consequence of the huge numbers of activated T cells is release of cytokines that cause capillaries to leak, resulting in many of the symptoms of the syndrome. 

When organisms are confronted with sudden changes such as exposure to potentially toxic substances (heavy metal ions) or the onset of starvation, these stimulations induce the production of the so-called stress responsive proteins. The most thoroughly studied stress proteins include the heat-shock proteins (HSP), the induction of which is a highly conserved response across genera. 

Kohler, H.R., Triebskom, R., Stocker, W. and Kloetzal, P.M. (1992) The 70kD heat shock protein (HSP70) in soil invertebrates a possible tool for monitoring environmental toxicants. Archives of Environmental Toxicology and Chemistry, 22, 334-338. 

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