1. Department of Biotechnology, Chemistry and Pharmacy; University of Siena; Via A. Moro 2 I-53100 Siena Italy
2. Department of Life Sciences; University of Siena; Via Aldo Moro 2 I-53100 Siena Italy
3. National Research Council (CNR); Institute of Biology and Agricultural Biotechnology, Research Area of Pisa; Via Moruzzi 1 I-56124 Pisa Italy