We investigate viruses containing protein, nucleic acid and lipid constituents that infect prokaryotic (bacterial and archaeal) hosts. These viruses are used as model organisms in understanding structure, assembly and function of biological macromolecular complexes. These studies have also shed light on the evolution and origin of viruses. We propose that seemingly unrelated viruses infecting hosts in all three domains of life may have a common origin.
Viruses currently under study include enveloped dsRNA phages in the Cystoviridae family (phi6–phi14), icosahedral dsDNA viruses: tectivirus PRD1, corticovirus PM2, and an archaeal virus SH1. We also screen for novel viruses from various natural environments for detailed structural and functional studies. These studies have resulted in the isolation of a novel group of pleomorphic viruses infecting archaea.
Furthermore, we have a keen interest in elucidating the structure and function of RNA-dependent RNA polymerases originating from dsRNA bacteriophages. Such polymerases, in addition to providing insight into the mechanisms of initiation, elongation and termination of the polymerization reaction, are valuable tools in biotechnology due to their capacity to produce dsRNA of practically unlimited length or amount for gene silencing.