Bayer E A, Rosenberg E, Gutnick D
J Gen Microbiol. 1981 Dec;127(2):295-300. doi: 10.1099/00221287-127-2-295.
The isolation of cell surface mutants of Acinetobacter calcoaceticus RAG-1 was demonstrated by a method based on the differential immunoprecipitating properties of wild-type cells and mutants. In the presence of antiserum, about 99% of wild-type cells in suspension sedimented following overnight agglutination. The kinetics of antiserum-induced agglutination was quantified by measuring the time-dependent decrease in turbidity. For mutant isolation, a sample of the cells remaining in the supernatant fluid served as inoculum for a fresh culture. This enrichment procedure of sequential growth and agglutination was repeated until the supernatant fluid following the overnight agglutination step remained turbid. Of the 40 colonies isolated in this manner, 34 exhibited altered agglutination properties. The agglutinability of wild-type cells varied with the phase of growth - cells harvested during the exponential phase were agglutinated better than those in stationary phase. In contrast, the antiserum-induced agglutination of most mutants was poor during the early phases of growth, but improved during late-stationary phase. One mutant failed to agglutinate in the presence of antiserum irrespective of the phase of growth.
通过一种基于野生型细胞和突变体的差异免疫沉淀特性的方法，证明了醋酸钙不动杆菌RAG-1细胞表面突变体的分离。在抗血清存在的情况下，过夜凝集后，悬浮液中约99%的野生型细胞沉淀。通过测量随时间变化的浊度降低来量化抗血清诱导凝集的动力学。为了分离突变体，将上清液中剩余的细胞样品用作新鲜培养物的接种物。重复这种连续生长和凝集的富集程序，直到过夜凝集步骤后的上清液保持浑浊。以这种方式分离的40个菌落中，34个表现出改变的凝集特性。野生型细胞的凝集性随生长阶段而变化——指数生长期收获的细胞比稳定期收获的细胞凝集性更好。相比之下，大多数突变体在生长早期抗血清诱导的凝集较差，但在稳定期末期有所改善。一个突变体在抗血清存在下无论生长阶段如何都不凝集。
