1. Departments of Physiology and Biophysics and
2. Department of Biophysics, Federal University of Sao Paulo, 04023-062 Sao Paulo;
3. Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, 31270 Minas Gerais;
4. University of Mogi das Cruzes, 087890-911 Mogi das Cruzes, Brazil; and
5. Max-Delbruck Center for Molecular Medicine, 13092 Berlin, Germany