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：1976
卷号：73
期号：2
页码：554-558
DOI：10.1073/pnas.73.2.554
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A soluble cell-free extract derived from stage 6 Xenopus laevis oocytes is described. From supercoiled simian virus 40 DNA the extract produces nicked circles (having a single-strand scission), linear molecules of full unit size, shorter length fragments, and various forms of complex DNA.
