A book that constitutes the first attempt to comprehensively assemble current knowledge of
different types of such elements highlight recent developments in the field and challenge the
distinction between viruses and linear plasmids. Linear plasmids of microbes represent a
heterogenous group of extrachromosomal genetic elements initially assumed to be rare and
peculiar. However we now know that they are fairly frequently occurring plasmids in bacterial
and eukaryotic species. Viral strategies to avoid shortening of the linear molecules during
replication imply a common ancestry.
