Summary
Salt-free and 0.2 M NaCl oxygenated aqueous solutions of poly-L-glutamic acid were irradiated with60Co-γ-radiation at variouspH's to examine whether or not the changes caused by the exposure to ionizing radiation depend onpH, that is, the conformations of polypeptide.
TheG-values (the number of main-chain scissions per 100 eV of energy absorbed) in both salt-free and 0.2 M NaCl solutions of poly-L-glutamic acid were found to change sharply withpH. and to have a maximum value at thepH of a mid-point of helix-coil transition. The change ofG-values withpH was discussed in terms of the conformational change of poly-L-glutamic acid.
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Kunikane, M., Sugai, S. The effects of γ-rays on poly-L-glutamic acid in aqueous solution. Biophysik 10, 221–228 (1973). https://doi.org/10.1007/BF01190581
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DOI: https://doi.org/10.1007/BF01190581