Rodenberg S, Steinberg W, Piper J, Nickerson K, Vary J, Epstein R, Halvorson H O
J Bacteriol. 1968 Aug;96(2):492-500. doi: 10.1128/jb.96.2.492-500.1968.
The rate of protein and ribonucleic acid (RNA) synthesis was examined during the outgrowth of spores of Bacillus cereus T in a chemically defined medium. RNA synthesis started 2.5 min after the initiation of germination, and protein synthesis after 4 min. Addition of a complete amino acid supplement and uracil supported high rates of RNA and protein synthesis throughout outgrowth. To determine the relationship between the rate of protein (k) and RNA synthesis, the kinetics of formation of various classes of RNA were followed during outgrowth. Ribosomal RNA (rRNA) comprised a relatively constant fraction of the total RNA throughout outgrowth (71 to 78%). The classes of RNA synthesized during this period were determined by germinating spores in radioactive uracil and then at intervals following their stability to actinomycin D. Initially, labile RNA comprised the largest fraction of newly formed RNA (DeltaRNA), and this proportion decreased during outgrowth. The ratio of k/rRNA or k/Delta stable RNA varied considerably during outgrowth, whereas the ratio of k/labile RNA remained constant. The data suggest that the rate of protein synthesis is not rigidly coupled to either total or newly synthesized rRNA (ribosomes) during the early stages of outgrowth.
在化学成分明确的培养基中，对蜡样芽孢杆菌T孢子萌发期的蛋白质和核糖核酸（RNA）合成速率进行了检测。RNA合成在萌发开始后2.5分钟启动，蛋白质合成在4分钟后启动。添加完整的氨基酸补充剂和尿嘧啶可在整个萌发期维持较高的RNA和蛋白质合成速率。为确定蛋白质合成速率（k）与RNA合成之间的关系，在萌发期跟踪了各类RNA形成的动力学过程。在整个萌发期，核糖体RNA（rRNA）在总RNA中所占比例相对恒定（71%至78%）。此期间合成的RNA种类通过在放射性尿嘧啶中萌发孢子，然后在对放线菌素D稳定后的不同时间间隔来确定。最初，不稳定RNA在新形成的RNA（ΔRNA）中占比最大，且这一比例在萌发期逐渐降低。k/rRNA或k/Δ稳定RNA的比值在萌发期变化很大，而k/不稳定RNA的比值保持恒定。数据表明，在萌发早期，蛋白质合成速率与总rRNA（核糖体）或新合成的rRNA并非严格偶联。
