1. Department of Biochemistry, University of Turku, SF-20500 Turku, Finland
2. Institute of Microbiology, Albert Szent-Györgyi Medical University, and Institute of Organic Chemistry, Szeged, Hungary
3. Blood Transfusion Centre, Albert Szent-Györgyi Medical University, and Institute of Organic Chemistry, Szeged, Hungary
4. JATE University of Science, Szeged, Hungary