1. Institute for Genome Research and Systems Biology, CeBiTec, Bielefeld University, PO Box 100131, D-33501 Bielefeld, Germany
2. Bruker Daltonik GmbH, Fahrenheitstr. 4, D-28359 Bremen, Germany
3. Proteome and Metabolome Research, Faculty of Biology, Bielefeld University, PO Box 100131, D-33501 Bielefeld, Germany
4. Department of Biological Sciences, Initiative for Bioinformatics and Evolutionary Studies, University of Idaho, Moscow, ID 83844-3051, USA