1. Gilead Sciences and IOCB Research Center, Institute of Organic Chemistry and Biochemistry of the Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n. 2, 166 10 Prague 6, Czech Republic
2. Department of Biochemistry, Faculty of Science, Charles University, Hlavova 8, Prague 2, Czech Republic
3. Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic, v.v.i., Videnska 1083, 140 00 Prague 4, Czech Republic
4. Department of Infectious Diseases, Specialty Laboratories, Valencia, California 91355
5. Department of Infectious Diseases, Quest Diagnostics Inc., San Juan Capistrano, California 92675