Recovery of Division Ability in Ultraviolet-irradiated Escherichia coli Induced by Photoreactivation, Photoprotection, and Liquid Holding Treatment

摘要

Small doses of ultraviolet light (UV, 265 mμ) cause Escherichia coli B to grow into long, multinucleate, nonseptate, filamentous cells. This UV-induced filament formation can be prevented by irradiating with photoprotecting light (335 mμ) prior to UV irradiation, and by irradiating with photoreactivating light (406 mμ), or by liquid holding treatment, after UV irradiation. It is concluded that UV-induced division inhibition in E. coli B is initially induced by repairable lesions in the deoxyribonucleic acid, probably pyrimidine dimers.