Biophysical Methods in Virus Research

All viruses are composed at least of protein and nucleic acid, and certain viruses contain other biochemical constituents as integral parts of their structure. Thus the biophysical methods used in the isolation and characterization of viruses are the same as those used by biochemists generally. It would be impossible in a chapter of reasonable length to deal with all such methods exhaustively. For that reason, an attempt will be made to limit this discussion to those most extensively used by virologists. The approach will be to explain the underlying principles involved in each method and to illustrate its use by citing examples drawn more or less randomly from the literature, including previous volumes of Comprehensive Virology. The purpose of the present effort is to provide readers not familiar with these methods a basis for understanding them, and perhaps some appreciation of which methods are best adapted to the solution of specific problems. However, anyone desiring to make use of any of the methods must consult more detailed specific treatments available in the literature. Certain methods, like electron microscopy and X-ray crystallography, are either so widely used or so highly technical that they deserve chapters in their own right, written by experts in the particular field. These methods are dealt with in Chapters 2 and 3 of this volume.