Bremer H, Dalbow D G
Biochem J. 1975 Jul;150(1):9-12. doi: 10.1042/bj1500009.
The concept of promoter efficiency is introduced as frequency of RNA chain initiation at a given promoter normalized to the intracellular concentration of free (but functional) RNA polymerase. Previous observations from this laboratory on the synthesis of ribosomes and beta-galactosidase are used to show that during a nutritional shift-up from succinate minimal to glucose-amino acids medium (3-fold increase in steady-state growth rate) the concentration of free (active) RNA polymerase decreases to one-quarter of the pre-shift value and the promoter efficiencies of the genes for ribosomal RNA and ribosomal proteins increase 9- and 6-fold respectively. This extent of control of ribosomal genes is much greater than expected on the basis of the increase in the rate of ribosome synthesis (3-fold).
启动子效率的概念是指在给定启动子处RNA链起始的频率,该频率已根据细胞内游离(但有功能)RNA聚合酶的浓度进行了归一化处理。本实验室先前关于核糖体和β-半乳糖苷酶合成的观察结果表明,在从琥珀酸最低培养基向葡萄糖-氨基酸培养基的营养上调过程中(稳态生长速率增加3倍),游离(活性)RNA聚合酶的浓度降至上调前值的四分之一,核糖体RNA和核糖体蛋白基因的启动子效率分别提高了9倍和6倍。核糖体基因的这种调控程度远高于基于核糖体合成速率增加(3倍)所预期的程度。