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：1972
卷号：69
期号：2
页码：515-519
DOI：10.1073/pnas.69.2.515
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Ordinarily, enzymes that catalyze bimolecular reactions involving DNA and nucleoside triphosphates are assayed in terms of the predicted changes in DNA. However, by assay of the enzymes by changes in nucleoside triphosphates, new enzymes may be sought without prior knowledge of the role of DNA in the reaction. This approach was used to isolate two new enzymes from Escherichia coli and one from T4 phage-infected E. coli. In this communication, the general application of this technique and its specific use in the isolation of two DNA-dependent ATPases from E. coli are described. Both enzymes catalyze a DNA-dependent cleavage of ATP to ADP and Pi. The two enzymes can be distinguished by their characteristic activities with different DNAs and synthetic polydeoxynucleotides. Neither of the enzymes shows endonuclease or exonuclease activity in conventional assays. These reactions were studied by isotope-exchange experiments. The discovery of these enzymes attests to the effectiveness of this method to seek new reactions involving nucleic acids. Moreover, our results suggest that other enzymes of nucleic acid metabolism may be found and purified by this new approach.
关键词：DNA-dependent ATPases ; purification ; properties ; E. coli
