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：1979
卷号：76
期号：12
页码：6289-6293
DOI：10.1073/pnas.76.12.6289
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A protein isolated from Escherichia coli complements the DNA gyrase A (NalA) protein to generate an activity that relaxes supercoiled DNA. Oxolinic acid, a known inhibitor of DNA gyrase, blocks this activity and causes double-strand cleavage of DNA at the same sites as are attacked by DNA gyrase. The protein, of molecular weight 50,000, appears to be fragment of the DNA gyrase B (Cou) protein (molecular weight, 90,000) as judged by the identical sizes of numerous peptides produced by partial proteolytic digestion. The complex of this fragment and the gyrase A protein lacks both the DNA-supercoiling and DNA-dependent ATPase activities of DNA gyrase.
