Planktonic Growth of around a Dual-Species Biofilm Supports the Growth of within That Biofilm.

PURPOSE

The goal of this study was to understand the potential interaction between and within the middle ear.

METHODS

We examined the microbiota of ear fluid and tympanostomy tubes (TTs) obtained from patients with posttympanostomy tube otorrhea. We also examined biofilms formed by and , singly or together, under aerobic or anaerobic conditions.

RESULTS

While the facultative anaerobe dominated the bacterial population within the ear fluid, strict anaerobes, including dominated bacterial populations within the TTs. was able to grow under aerobic conditions only in the presence of , whose growth reduced the level of dissolved oxygen within the broth to nearly anoxic condition within 4 h after inoculation. The presence of allowed to maintain its growth for 72 h within the dual-species biofilm but not within the planktonic growth. Visualization of the biofilms revealed coaggregation of and .

CONCLUSION

Extrapolation of these results suggests that, within the middle ear fluid, the growth of produces the anaerobic conditions required for the growth of , both within effusion and within biofilms.