CHARACTERIZATION OF FIBRINOLYTIC-ACTIVITIES OF TREPONEMA-DENTICOLA

Several fibrinolytic activities of Treponema denticola, an oral spiroc hete associated with gingivitis and periodontal disease, were identifi ed and characterized following phase partitioning with the nonionic de tergent Triton X-114. The apparent molecular masses of the proteases r anged from 91 to 228 kDa when analyzed in sodium dodecyl sulfate-polya crylamide gels containing fibrinogen as the protease substrate. A qual itative analysis of zymograms showed that the proteases were highly en riched in the detergent phase, although the 91-, 173-, and 228-kDa pro teases were also found in the aqueous phase. Zymograms of crude outer sheaths prepared by repeated freezing-thawing revealed that the protea ses may be associated with this subcellular compartment. The proteases displayed substrate specificity towards fibrinogen, were susceptible to sulfhydryl group reagents, and had a pH optimum between 7 and 8. Th e similarities in their sensitivity to inhibitors, temperature stabili ty, pH optimum, and laddered protein profiles suggest that these hydro lytic enzymes may be part of a family of oligomeric proteases that may play an important role in the invasiveness of and tissue damage cause d by the spirochete.