Lundegårdh, H & Larkum, AWD 1965, 'The action of ionizing radiation on the respiratory mechanism of baker's yeast', BBA - General Subjects, vol. 97, no. 3, pp. 422-433.
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1. 1. The effect of ionizing radiation on the cytochrome chain and associated systems in baker's yeast was studied by means of a specially constructed scanning spectrophotometer and by tracer technique. 2. 2. The basic mechanism for electron transport through the respiratory system was resistant to irradiation up to 200 000 R. 3. 3. An inhibition of phosphorylation was observed from 10 000 R onwards, but even the highest doses produced only 33% inhibition. 4. 4. Respiration was stimulated increasingly from low intensities of irradiation upwards, but irregular oxidations bypassing the important step cytochrome b-cytochromec interfered at intensities above approx. 10 000 R. 5. 5. Salts (NaCl, KCl) and ADP counteracted the effects of moderate radiation on all processes, and helped counteract the irregular oxidations. At higher intensities of irradiation, some beneficial and some deleterious effects of salts and ADP were observed. The beneficial effect of ADP at moderate radiation reinforces the other observations that radiation has a greater effect on the energy converting systems than on the basic mechanism of electron transport. © 1965.