Department of Bioinformatics, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 6, 166 10, Czech Republic.|Department of Bioinformatics, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 6, 166 10, Czech Republic.|European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Cambridge, UK.