FIG. 8.

Hemolysis, growth rates, and transmission electron microscopy of P. gingivalis W50, PG1051-KO, and PG1051⁺ strains. (A) P. gingivalis W50, PG1051-KO, and PG1051⁺ strains were grown anaerobically on a blood agar plate for 4 days. (B) Strains were grown in an anaerobic cabinet in BHI broth supplemented with hemin. Samples were withdrawn at different time points, and the optical density was measured at 540 nm for 6 days. ▴—▴, P. gingivalis W50; (▴—▴), PG1051-KO; ▪, PG1051⁺. (C and D) Electron micrographs of P. gingivalis W50 (C) and PG1051-KO mutant strains (D) grown in liquid culture (24 h). Arrows indicate the electron-dense region surrounding P. gingivalis W50 cells.