Watson S W, Mandel M
J Bacteriol. 1971 Aug;107(2):563-9. doi: 10.1128/jb.107.2.563-569.1971.
The gross morphology, fine structure, and per cent guanine plus cytosine (GC) composition of deoxyribonucleic acid of 27 strains of nitrifying bacteria were compared. Based on morphological differences, the ammonia-oxidizing bacteria were separated into four genera. Nitrosomonas species and Nitrosocystis species formed one homogenous group, and Nitrosolobus species and Nitrosospira species formed a second homogenous group in respect to their deoxyribonucleic acid GC compositions. Similarly, the nitrite-oxidizing bacteria were separated into three genera based on their morphology. The members of two of these nitrite-oxidizing genera, Nitrobacter and Nitrococcus, had similar GC compositions, but Nitrospina gracilis had a significantly lower GC composition than the members of the other two genera.
对27株硝化细菌的脱氧核糖核酸的总体形态、精细结构以及鸟嘌呤加胞嘧啶（GC）的含量进行了比较。基于形态学差异，将氨氧化细菌分为四个属。亚硝化单胞菌属和亚硝化囊菌属在脱氧核糖核酸的GC含量方面形成一个同质组，而亚硝化螺菌属和亚硝化螺旋菌属形成第二个同质组。同样，根据形态学将亚硝酸盐氧化细菌分为三个属。其中两个亚硝酸盐氧化属的成员，硝化杆菌属和硝化球菌属，具有相似的GC含量，但纤细硝化刺菌的GC含量明显低于其他两个属的成员。
