Role of Capsule in Resistance to Disinfectants, Host Antimicrobials, and Desiccation in Acinetobacter baumannii

Acinetobacter baumannii strain AB5075 forms two cell types distinguished by their opaque (VIR-O) or translucent (AV-T) colonies. VIR-O cells possess a thicker capsule and are more resistant to a variety of stressors than AV-T cells. However, the direct role of the capsule in these stressors was unknown. This study demonstrates that the capsule is required for resistance to disinfectants, lysozyme, and desiccation in Acinetobacter baumannii. In addition, the capsule is required for survival in a mouse lung model of infection.