Wang C H, Koch A L
J Bacteriol. 1978 Dec;136(3):969-75. doi: 10.1128/jb.136.3.969-975.1978.
An apparatus has been developed in which bacterial growth can be measured very precisely over short intervals of time. Its precision is presented and used to assess the constancy of growth in batch culture. Under certain conditions, i.e., Luria broth or 0.2% glucose-M9 medium at very low cell densities, the specific growth rate of Escherichia coli appeared to be constant within the measurement limits of the method. In succinate minimal medium, the growth rate increased gradually over several days and never became constant. With nutrient broth and with Luria broth, growth slowed progressively at moderate cell densities within the range considered to be in the logarithmic phase of growth. In addition, temporary slowdown in growth rate occurred in these two complex media at characteristic cell densities. These gradual increases in succinate minimal medium and temporary slowdowns in the complex media would be undetectable without precise measurements and may have been a source of variability in many bacteriological studies.
已开发出一种装置，可在短时间间隔内非常精确地测量细菌生长。介绍了其精度，并用于评估分批培养中生长的稳定性。在某些条件下，即在极低细胞密度下的Luria肉汤或0.2%葡萄糖-M9培养基中，大肠杆菌的比生长速率在该方法的测量范围内似乎是恒定的。在琥珀酸盐基本培养基中，生长速率在几天内逐渐增加，且从未恒定。对于营养肉汤和Luria肉汤，在被认为处于对数生长期的中等细胞密度范围内，生长逐渐减慢。此外，在这两种复杂培养基中，在特征性细胞密度下会出现生长速率的暂时减慢。如果没有精确测量，琥珀酸盐基本培养基中的这些逐渐增加以及复杂培养基中的暂时减慢可能无法检测到，并且可能是许多细菌学研究中变异性的一个来源。
