Centro Nacional de Análisis Genómico-Centre for Genomic Regulation, Barcelona Institute of Science and Technology (CNAG-CRG), Barcelona, Spain.|Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, IL, USA.|Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, IL, USA.|Institute of Informatics, Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology, Gliwice, Poland.