Detection of colonies of Bacteroides gingivalis by a rapid fluorescence assay for trypsinlike activity

The synthetic fluorogenic compound carbobenzoxy‐L‐arginine‐7‐amino‐4‐me‐thylcoumarin amide‐HC1 (CAAM) was evaluated for its ability to detect trypsin‐like activity in colonies of Bacteroides gingivalis. CAAM fluoresced with all B. gingivalis isolates tested and did not react with other human black‐pigmented bacteroides species. The utility of the CAAM test for rapid presumptive identification of B. gingivalis is discussed.