期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1970
卷号：67
期号：1
页码：255-262
DOI：10.1073/pnas.67.1.255
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The pattern of new growing forks in the Escherichia coli genome after a period of inhibition of DNA synthesis has been examined. Synchronous cultures of E. coli B/r were treated with nalidixic acid to stop DNA synthesis for various lengths of time. After removal of the nalidixic acid the location of active growing forks was determined by measuring the reversion rate of a histidine requirement induced by the "growing-point mutagen," nitrosoguanidine. It was found that the ability to initiate a new round of DNA synthesis upon release from the nalidixic acid block was attained at the cell age at which a new round of replication would have been initiated had DNA synthesis not been blocked. However, if the nalidixic acid was removed before the normal initiation age, the initiation of the next round of synthesis was delayed past the normal time, which indicates that initiation of new rounds is not completely independent of DNA synthesis.
