1. Department
of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Carretera
de Ajalvir km 4, Torrejón de Ardoz, 28850 Madrid, Spain
2. Department
of Biology, Universidad Autónoma de Madrid, Campus de
Cantoblanco, 28049 Madrid, Spain
3. Centro Nacional de Biotecnología (CSIC), c/Darwin 3, 28049 Madrid, Spain