Studies on virus-host relationships and genome organisation of viruses infecting hyperthermophilic acidophilic archaea of the genus Acidianus

• Applicant: Dr. David Prangishvili
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2002 to 2004
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5378118

Studies of the extent and distribution of viral diversity on the planet should help to understand the role of viruses in microbial ecology and the entire ecosystem. A comprehensive picture of viral diversity could also contribute to understanding the orgin and evolution of viruses, and probably very early stages of cellular evolution. Because of the remarkable diversity of their morphologies suggesting a broad phylogenetic span, viruses of the archaea, mainly of those thriving in hot habitats, are especially promising objects of evolutionary studies. Such viruses also offer comprehensible model systems for understanding the biochemistry of life at high temperatures, as well as possibilities to establish transformation and expression systems for hyperthermophilic archaea. The aim of the project is to study 9 novel viruses and virus-like particles produced by strains of the hyperthermophilic archaeal genus Acidianus, which we have discovered in enrichment cultures from a sample from an acidic hot spring (pH 2, 85°C) in Yellowstone National Park, Wyoming, USA. Four types of particles morphologically resemble known viruses of the hyperthermophilic archaea Sulfolobus and Thermoproteus. Morphologies of other particles are unique, not observed previously in nature. We plan to isolate a natural host for each of the viruses and virus-like particles, study particle structures and relationships with hosts, and determine and analyse nucleotide sequences of the genomes.

• DFG Programme: Research Grants