Summary
Exponential phase cultures ofE. coli 15 T- cells growing on glucosemineral medium were supplemented with 2 mM l-cysteine-HCl. The optical density, acid soluble SH (AS-SH) as well as the DNA, RNA, and protein synthesis of the cultures were examined during this treatment and after return to normal growth conditions. Similarly, the survival of cells irradiated by a standard X-ray dose in cysteine-free buffer was measured.
The development of radioresistance during the cysteine treatment as well as the loss of this acquired radioresistance after return to normal growth conditions could be divided into two phases: a) an instantaneous and b) a slow change of radioresistance. Phase “a” seems to be related to the changes occurring in the AS-SH content of the bacteria, while phase “b” is apparently dependent on the alterations in the synthesis of macromolecules.
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Nagy, Z., Kovács, P., Kari, C. et al. New data on the toxic and radioprotective effect of cysteine onEscherichia coli 15 T- cells. Archiv. Mikrobiol. 70, 65–71 (1970). https://doi.org/10.1007/BF00691060
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DOI: https://doi.org/10.1007/BF00691060