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：1973
卷号：70
期号：1
页码：164-168
DOI：10.1073/pnas.70.1.164
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The RNA-dependent DNA polymerase of Rous sarcoma virus is inhibited by N-methyl isatin {beta}-thiosemicarbazone and by thiosemicarbazide, but not by semicarbazide. These inhibitors also inactivate, upon contact with the virion, the transforming ability of Rous sarcoma virus. Sulfhydryl donors, such as 2-mercapto-ethanol, can prevent these effects. The RNA-directed activity of the purified polymerase is inhibited to a greater degree than is the DNA-directed activity. Two cations, Cu++ and Hg++, can inhibit RNA-dependent DNA polymerase and inactivate the transforming ability of the virus. Synergism between N-methyl isatin {beta}-thiosemicarbazone and Cu++ occurs, since treatment of the virus with a low dose of either N-methyl isatin {beta}-thiosemicarbazone or Cu++ has little effect; however, when the two compounds are mixed together, significant inactivation occurs. This observation supports the hypothesis that the antiviral action of thiosemicarbazones is a function of their ability to act as a ligand for metallic ions. Several cations (Ag+, Co++, Zn++, Cd++, and Ni++) significantly inactivate the RNA-dependent DNA polymerase, but have little effect on the transforming ability. In view of this result, the conclusion that the enzyme activity is required for transformation remains open to question.
