Genetic Determinants Of The Superantigens

All known streptococcal SAgs with the exception of SMEZ, SPE G, and SPE J are encoded by bacteriophage genes integrated in the bacterial chromosome.[4,9,14] Four naturally occurring speA alleles have been found in strains recovered from patients with severe invasive diseases. Three of these speA 1, speA2, and speA3 encode toxins differing by a single amino acid. The toxin encoded by speA4 was 9% divergent from the other three ones with 26 amino acid changes. Strains expressing speA2 and speA3 have caused the majority of STSS episodes in the past 12 years, suggesting that the gene products, SPE A2 and SPE A3, may be the more bioactive toxic forms of the toxin. This may be due to higher affinity to HLA-DQ molecule. Four alleles of speC have been described and 24 for smez gene.[17] Detailed studies on SMEZ-2[19] and SMEZ-16[20] proteins showed that they are the most potent SAgs (in terms of mitogenic activity) discovered thus far.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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