Atomic force microscopy of bacterial communities

This chapter discusses atomic force microscopy (AFM) for the benefit of microbiologists who are interested in using this technique to examine the structures and dynamics of bacteria. AFM is a powerful technique for imaging biological samples at the nanometer to micrometer scale under nondestructive conditions. In order to be imaged with AFM, bacteria must be supported by a surface, which presents challenges because many laboratory strains of bacteria are planktonic. Still, in nature many bacteria live at surfaces and interfaces. This chapter discusses the benefits and difficulties of different methods that have been used to support bacteria on surfaces for AFM imaging and presents two methods in detail used to successfully grow and image bacteria at solid-liquid and solid-air interfaces. Using these methods it is possible to study bacterial morphology and interactions in a native state. These explorations by AFM have important applications to the study of different kinds of bacteria, interfacial bacterial communities, and biofilms.