1. School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, U.K.
2. School of Biology, The University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, U.K.
3. Department of Molecular Biology, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia