Fig 7. Interpreting the benefits of loss of flagellar function in laboratory biofilms and CF.

The classic interpretations for loss of the flagellum view evasion of the host immune system and a decreased doubling time as fitness benefits that could lead to the evolution of non-flagellated bacteria during infection. We propose that selection for gain-of-function phenotypes related to exopolysaccharide production offers a new way for interpreting the causes and consequences of flagellar gene mutation in biofilms and CF infection.