The invention of freeze fracture EM and the determination of membrane structure

William A. Wells

doi:10.1083/jcb1682fta2

$<h2>The invention of freeze fracture EM and the determination of membrane structure</h2> William A. Wells wellsw@rockefeller.edu Plane through a crystal of tobacco ringspot virus (left) made using Steere's do-it-yourself cold operating box (middle). A later freeze fracture image is shown at right. STEERE/STAEHELIN Russell Steere believed that different was good. His new method of freeze fracture electron microscopy (EM) might not be perfect, but “if artifacts”—the bane of all EM work—“are produced by this type of fixation they should at least differ from those resulting from chemical fixation.” With this modest claim, Steere et al. (1957) introduced a method that has played “an absolutely critical role in the elucidation of membrane structure,” according to L. Andrew Staehelin (University of Colorado, Boulder, CO). Steere started with frozen samples and then combined a series of known methods—using an ultramicrotome for cutting, freeze drying to etch and expose surface features, and finally creating a replica with heavy metals. After Steere's initial demonstration of the method on virus particles, a group in Zurich converted Steere's rather home-made contraption into a more robust instrument (Moor et al., 1961; Moor and Mühlethaler, 1963). The Zurich group was most interested in nuclear and chromosomal structure—the$

The invention of freeze fracture EM and the determination of membrane structure

Wells, William A.

Follow The Journal of Cell Biology , Volume 168 (2): 174 Rockefeller University Press – Jan 17, 2005