1. Center for Genomic Sciences, Allegheny-Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212, United States
2. Department of Microbiology and Immunology, Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania 15212, United States
3. Department of Otolaryngology, Head and Neck Surgery, Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania 15212, United States
4. Bruker Daltonics, Billerica, Massachusetts 01821, United States
5. Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523