Investigating microbial ecology at solid-air interfaces

Despite the ubiquity of biofilms in many environments, most microbiological study has focussed on their existence under aqueous conditions. The ecology of bacteria at solid-air interfaces is a significant concern in clinical settings, where prevention of nosocomial infection is a priority. Although multi-species communities are predominant in the environment, most laboratory research regarding bacterial survival at solid-air interfaces has focussed on pure culture survival. Therefore, the focus of this thesis was to determine whether community interactions affect the survival of bacteria after drying on exposed surfaces. It was determined that exogenous pathogens can exhibit enhanced survival after drying in the presence of members of the indoor bacterial flora. The enhanced survival of desiccation-sensitive species in communities is likely dependent on the density of cells on the surface and is thought to involve direct or close contact between community members, allowing poor-survivors to benefit from the desiccation-tolerance mechanisms of others. This project represents an exploratory study into bacterial ecology at solid-air interfaces within indoor environments.