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：1977
卷号：74
期号：1
页码：111-114
DOI：10.1073/pnas.74.1.111
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Low concentrations of the dye tetraiodofluorescein activate native aspartate transcarbamylase (aspartate carbomoyltransferase, carbomoylphosphate:L-aspartate carbomoyltransferase, EC 2.1.3.2 ), while high concentrations inhibit the enzyme's activity [Jacobsberg, L. B., Kantrowitz, E. R. & Lipscomb, W. N. (1975) J. Biol. Chem. 250, 9238-9249]. This dye is now shown to produce similar effects upon a modified form of aspartate transcarbamylase produced by Escherichia coli grown in a culture medium supplemented with thiouracil. Significantly, the ATP-induced activation is reduced in the modified form of the enzyme to the same extent as is the tetraiodofluorescein-induced activation. Thus, a relationship is demonstrated between the internal mechanisms by which ATP and tetraiodofluorescein activate aspartate transcarbamylase.
