Moiré Patterns in Electron Micrographs of a Bacterial Membrane

Abstract

A regular hexagonal array of morphological units is observed in negatively stained preparations of a membrane from the surface of the spherical bacterium Micrococcus radiodurans. Fragments of this membrane are frequently folded so that structural details from two or more layers are superimposed. The appearance of the resulting moiré patterns is illustrated and the need to be aware of the possibility of the formation of these patterns in similar biological specimens is stressed.