NAME: Kevin Cowtan

AFFILIATION: University of York, UK

CONTACT: cowtan@ysbl.york.ac.uk

TITLE: "Fitting small fragments into electron density"

ABSTRACT: There have been a number of applications of molecular-replacement-like and other techniques for placing atomic models or model fragments into electron density maps phased by experimental or other means. The fragments have varied in size from 4 atoms to a whole molecule. The 6-dimension rotation-translation search has been accomplished by brute force methods and by using Fourier methods for various combinations of the rotation and translation parts of the search. A survey of some these methods is presented, along with a recent application to the problem of protein chain tracing.