CULTIVATION AND ISOLATION OF MOUTH SPIROCHETES

¹ Department of Pathology and Bacteriology, Johns Hopkins University, Baltimore, Mid.

Pure cultures of spirochetes have been obtained from fusospirochetal mouth lesions. The isolation of these strains was accomplished by filtration through Chamberland-Pasteur filters, by cultivation in deep agar shake tubes and by cultivation in the depth of blood agar plates.

Nineteen strains of mouth spirochetes may be divided into 3 groups on the basis of their morphology and their cultural characteristics:

Group A (S 26, S 58-1 and S 58-33): large, regularly coiled spirochetes which do not require blood for the maintenance of pure subcultures. These spirochetes ferment dextrose with the production of acid. Colonies in blood agar plates are surrounded by a zone of partial hemolysis.

Group B (S 84): irregularly coiled spirochetes which require the presence of blood for the maintenance of the strain. Their ability to attack carbohydrates has not yet been determined. These spirochetes have refused to grow in the depth of blood agar plates.

Group C (the remaining 15 strains): small, regularly coiled spirochetes which require the presence of blood in stock culture media. Eight spirochetes of this group do not ferment dextrose. The other 7 strains have not been studied sufficiently to report on their carbohydrate metabolism. Colonies in blood agar are surrounded by a zone of partial hemolysis.