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：11
页码：4017-4021
DOI：10.1073/pnas.73.11.4017
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The molecular mechanism of enzyme (phenylalanine ammonia-lyase; EC 4.3.1.5 ) formation mediated by phytochrome in mustard seedlings was investigated by labeling the enzyme with deuterium followed by high resolution CsCl density gradient analysis. A favorable relationship between induced rise of activity and turnover of this short-lived enzyme (half-life 3-4 hr) was achieved by labeling pre-irradiated seedlings. The time course of deuterium incorporation during the light-mediated rise in enzyme activity that can be derived independently from density shifts and bandwidth changes demonstrates a stimulation of synthesis and degradation by phytochrome. When synthesis is faster than degradation, enzyme accumulates.
关键词：enzyme synthesis versus activation ; density labeling
