1. Department of Biotechnology, Yonsei University, Seoul 120-749, Korea
2. Bioinformatics and Molecular Design Research Center, Seoul 120-749, Korea
3. Gulf Ecology Division, U.S. Environmental Protection Agency, Gulf Breeze, Florida 32561, United States
4. Department of Chemistry, University of North Texas, 1155 Union Circle Drive #305070, Denton, Texas 76230-5017, United States