Proteolytic Activities of Some Oral Spirochetes

¹ National Institute of Dental Research, National Institutes of Health Bethesda, Maryland

The proteolytic activities during the growth phase of two strains of B. vincentii and two of a small oral treponeme were demonstrated. The parent strain of B. vincentii (N9) and the adapted variant (N9-G), which was adapted to grow in the absence of ascitic fluid, grew equally well in their respective media and showed evidence of significant proteolytic activity. Cultures of the two strains of the small oral treponeme (FM and FM-G) showed greater proteolytic activity than did the B. vincentii strains.

The greatest degree of proteolysis by all strains was observed to coincide with the logarithmic growth phases, occurring during the second through the seventh days. During the stationary phases, there were diminished activities, especially with the Borrelia strains.