1. Novartis Vaccines and Diagnostics S.r.l., Via Fiorentina 1, 53100 Siena, Italy.
2. Genomics Institute of Novartis Research Foundation, 10672 John Jay Hopkins Drive, San Diego, CA 92121, USA.
3. Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.