1. Department of Computer and Data Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
2. Department of Computer Engineering, Bilkent University, Ankara 06800, Turkey
3. Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH 44106, USA
4. Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA 15213, USA
5. Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey