1. Computational Science, University of Amsterdam1081 HV Amsterdam, The Netherlands
2. Centre for Computational Science (CCS), University College LondonLondon WC1H 0AJ, UK
3. Institute of Biology, Eötvös Loránd University1117 Budapest, Hungary
4. Department of Virology, Erasmus Medical Center Rotterdam3000 CA Rotterdam, The Netherlands
5. Institute of Computer Science AGH30-056 Krakow, Poland