A computational framework for the 3D structure determination of viruses with unknown symmetry

The protein shell of all virus structures resolved to this date exhibit some form of symmetry, most of them are spherical viruses with icosahedral symmetry; the study of viruses whose symmetry is not known, of structures which do not exhibit any symmetry, as well as the study of the genetic material of a virus are considerably more challenging. Increasing the resolution of the structure determination and solving structures with no symmetry represents a quantum leap in virus structure determination based upon electron microscopy. Computing is a major component of the structure determination process. Nowadays it is not feasible to increase the resolution of the structure determination of large macromolecules like viruses or to solve structures with no symmetry without novel parallel algorithms and environments enabling structural biologists to use parallel systems, clusters of workstations, or providing access to grid computing. (C) 2003 Elsevier Inc. All rights reserved.