Kepes F, Kepes A
Ann Microbiol (Paris). 1980 Jan-Feb;131(1):3-16.
Growth of bacteria in a fermentor is limited by an essential nutrient here inorganic phosphate. After starvation, the culture is diluted by an automatic device in such a way that the limiting nutrient concentration allows exactly one doubling. After 10 to 16 automatic cycles, which can be achieved overnight, synchronous bacterial cycles can be observed to occur spontaneously in non-limiting culture conditions, i.e. open systems. The operating procedures of the prototype are outlined. This "Automatic Synchronizer" has a capacity of about 0.1 g dry bacterial weight per cycle. Synchrony and homogeneity index are suggested, and applied to concrete examples of synchronous growth in closed and open systems. The maintenance of good synchrony in an open system throughout 6 cell cycles allows one to consider microbial growth and metabolism in a culture as reflecting the time schedule of the individual cell instead of being related to the statistical mean of a random cell population. The contradiction between the generation time variability observed under the microscope for individual clones and the amazing maintenance of good synchrony in our culture, is also discussed.
发酵罐中细菌的生长受到一种必需营养物质（此处为无机磷酸盐）的限制。饥饿处理后，培养物由自动装置进行稀释，使得限制性营养物质的浓度恰好能让细菌数量翻倍一次。经过10到16个自动循环（这可以在一夜之间完成），可以观察到在非限制性培养条件下，即开放系统中，同步细菌循环会自发出现。文中概述了该原型的操作程序。这种“自动同步器”每个循环的处理能力约为0.1克干细菌重量。文中提出了同步性和同质性指数，并应用于封闭和开放系统中同步生长的具体实例。在开放系统中6个细胞周期内都能保持良好的同步性，这使得人们可以认为培养物中的微生物生长和代谢反映的是单个细胞的时间进程，而非与随机细胞群体的统计平均值相关。文中还讨论了在显微镜下观察到的单个克隆的世代时间变异性与我们培养物中惊人的良好同步性维持之间的矛盾。
