1. Department of Biochemistry, University of Utah School of Medicine, 15 North Medical Drive East, Room 4100, Salt Lake City, Utah 84112-5650, USA
2. Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, CA 94304, USA
3. Departamento de Microbiología, Universidad de Granada, Avda. Fuentenueva, s/n, 18071 Granada, Spain