Atomic Force Microscopy Characterization of Reconstituted Protein-DNA Complexes

Atomic force microscopy is a high-resolution imaging technique useful for observing the structures of biomolecular complexes. This approach provides a straightforward method to characterize the binding behavior of different chromatin architectural proteins and to analyze the increasingly complex structural units assembled on the DNA. The protocol describes the preparation, AFM imaging, and structural analysis of chromatin that is reconstituted in vitro using purified proteins and DNA. Here, we describe the successful application of the method on the chromatin architectural proteins of the archaeon Sulfolobus solfataricus.