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Synergohymenotropic toxin

Venkata Meka, M.D.


               Synergohymenotropic toxins are a family of bicomponent toxins that act thru the synergistic activity of 2 non-associated secretory proteins. In the case of PVL, these two components are designated protein class S and F, on the basis of their slow or fast elution in cation-exchange carboxy-methyl cellulose chromatography. These proteins are encoded by two contiguous and cotranscribed genes, lukS-PV and lukF-PV. In S. aureus, gamma-hemolysin is another bicomponent toxin that is encoded by three genes HlgA and HlgC (belonging to class S) and HlgB (belonging to class F). This results in 2 pairs of class S and F components- HlgA and HlgB, HlgC and HlgB. This is an important characteristic of this class of toxins; various combinations of class S and F components result in different bicomponent toxins. These toxins create lytic pores sensitive to monovalent cations and are assembled from the two components secreted separately by the organism as water-soluble molecules.



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