Affiliation:
1. From the Departments of Biophysics and Biochemistry, The Johns Hopkins University, Baltimore
Abstract
Hemophilus influenzae—transforming DNA, which has been inactivated by ultra-violet radiation, is reactivated by visible light in the presence of a cell-free extract of Escherichia coli B.
The time rate of reactivation is increased by increasing the E. coli extract concentration, the temperature, and the intensity of illumination.
Only DNA containing an ultraviolet-damaged genetic marker exhibits increased transforming activity after treatment with the photoreactivating system.
The reactivating capacity of the extract remains in the top supernatant after centrifugation at 110,000 x g for 1 hour and is not present in the pellet. This capacity is destroyed by heating to 90°C. for 1 minute.
The active system of the E. coli extract is separable into dialyzable, heat-stable and non-dialyzable, heat-labile fractions. The dialyzable fraction contains at least one component which limits the maximum degree of recovery attained.
Publisher
Rockefeller University Press
Cited by
192 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献