Scanning electron micrographs of a P Scanning electron micrographs of a P. acnes strain ATCC 11827 biofilm on solid soda lime glass beads (Walter Stern Inc., Port Washington, NY), incubated with P. acnes for 2 days anaerobically at 37°C under static conditions (magnifications, ×2,000 [A] and ×20,000 [B]; beam accelerating voltage, 1 kV; working distance, 3 mm) (Zeiss Supra 55VP field emission scanning electron microscope). Scanning electron micrographs of a P. acnes strain ATCC 11827 biofilm on solid soda lime glass beads (Walter Stern Inc., Port Washington, NY), incubated with P. acnes for 2 days anaerobically at 37°C under static conditions (magnifications, ×2,000 [A] and ×20,000 [B]; beam accelerating voltage, 1 kV; working distance, 3 mm) (Zeiss Supra 55VP field emission scanning electron microscope). Yvonne Achermann et al. Clin. Microbiol. Rev. 2014; doi:10.1128/CMR.00092-13