The use of EM and image analysis techniques, particularly the single particle methodology, has opened the door to the structural characterization of large protein complexes in the megadalton range. This review covers the basic principles of single particle EM and recent examples of its application to the study of large molecular machines in the eukaryotic cell. These examples will give the read...

Molecular machines are tiny energy conversion devices on the molecular-size scale. Whether naturally occurring or synthetic, these machines are generally more efficient than their macroscale counterparts. They have their own mechanochemistry, dynamics, workspace, and usability and are composed of nature's building blocks: namely proteins, DNA, and other compounds, built atom by atom. With moder...

some organic molecules can be isomerized upon photoirradiation and when accompanied by a change in the visible absorption spectrum, it is called photochromism. azobenzenes are important part of molecular machines and nanotechnology, which are this phenomenon is called photoisomerization azobenzene (azo) chromophores , and have been incorporated into a wide variety of materials and molecular arc...