Genetic relationships of short and long anaerobic curved rods isolated from the vagina.

DNA from anaerobic curved rods (CR) isolated from the human vagina were analysed regarding sequence homology and guanine + cytosine content. Of the strains of CR tested, ten belonged to the short (SCR) (approximately 1 micron) and eight to the long (LCR) (approximately 2-4 micron) CR type. A low level of homology (5-10%) was found between SCR and LCR. The LCR were a fairly homogeneous group of bacteria, with homologies ranging from 70 to 100%. The SCR fell into three DNA homology groups: one with 85%, and another with approximately 60% homology, while two strains belonging to the latter group hybridized with only 33%.