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:1974
卷号:71
期号:5
页码:2136-2140
DOI:10.1073/pnas.71.5.2136
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The relative content in ribosomes of L7 and L12, the two forms of a protein in the 50S subunit specifically involved in GTP hydrolysis, is found to undergo a striking shift with the growth phase of E. coli. The content of L12 (nonacetylated form) increases during early logarithmic phase, becoming about 85% of the total before midlogarithmic phase. Thereafter, L7 (N-acetylated form) content begins to increase, eventually becoming 75-80% in stationary phase. The L7 + L12 content per ribosome, however, remained constant during this shift. Our evidence suggests that the shift did not occur through modification of preexisting ribosomes. The data further indicate that the E. coli cell may contain more than one structurally distinct (with regard to L7 or L12 content) 50S subunit population.
关键词:ribosome heterogeneity ; regulation of acetylation ; stationary phase adaptation