Computer Averaging of Electron Micrographs of 40 <i>S</i> Ribosomal Subunits

Abstract

An enhanced lateral view of the 40S ribosomal subunit of HeLa cells has been obtained by computer averaging of single particles visualized in the electron microscope. Application of crystallographic criteria to independent averages shows that the reproducibility of the result is comparable to that obtained for thin, stained protein crystals by conventional Fourier filtration methods.