Iodine complex protein effects

It is widely employed as a disinfectant in medicine (Povidone-iodine) because of its mildness, low toxicity, and water solubility. According to the U.S. Pharmacopeia, l ovidone-iodme is a free-flowing, brown powder dial contains from 9-12% available iodine. 11 is soluble in water and lower alcohols. When dissolved in water, the uncomplexed free iodine level is very low however, tine complexed iodine acts as a reservoir and by equilibrium replenishes the free iodine lo the equilibrium level. This prevents free iodine from being deactivated because the free form is continually available at effective biocidal levels from this large reservoir. PVP will interact with other small anions and resembles serum albumin and other proteins in this regard. It can be salted in with anions such as NaSC.N or out with NasSOa much like water-soluble proteins. 

Da. The toxins are made up of two polypeptide chains (A and B) connected by a disulfide bond. The cytotoxicity of ricin is due to inhibition of protein synthesis, caused when the B chain binds to cell-surface receptors and the toxin-receptor complex is taken into the cell, and the A chain that has endonuclease activity and, at extremely low concentrations, will inhibit DNA replication and protein synthesis (USAMRICD, 2005). Ricin is stable under ambient conditions and can be detoxified by heat at 80°C for 10 min, or 50°C for an hour at a pH of 7.8. Chlorine inactivates over 99.4% by 100 mg/L FAC in 20 min. Low chlorine concentrations, such as 10 mg/L FAC, as well as iodine at up to 16 mg/L will have no effect on ricin (USAMRICD, 2005). 

The effects of a number of other perturbations on the interaction of RBP with TTR (and on the interactions of these proteins with their ligands retinol and thyroxine, respectively) have been explored. The other manipulations that have been examined include effects of changes in temperature and urea concentration and the effects of reduction and alkylation of disulfide bonds and of iodination (Raz et al., 1970) the effects of modifications of tyrosine, lysine, and tryptophan residues were also examined (Heller and Horwitz, 197S Horwitz and Heller, 1974b). Addition of 6 Af urea completely disrupted the RBP-TTR complex, markedly reduced the affinity of TTR for thyroxine, but did not interfere with the association of RBP with retinol. Iodination of isolated RBP decreased its affinity for TTR (Raz et al., 1970 Vahlquist, 1972 Vahlquist et al., 1973). However, it was found (Vahlquist, 1972 Vahlquist et al., 1973) that iodination of the RBP-TTR complex, followed by the dissociation of the complex and separate isolation of the two proteins, yielded iodinated RBP with full affinity for... 

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