1. Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Poznań 60-632, Poland
2. Mass Spectrometry Laboratory, Institute of Biochemistry and Biophysics, PAS, Warsaw 02-106, Poland
3. International Center for Public Health, Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School, Newark, New Jersey 07103, United States