1. Bioelectrochemistry Laboratory, Water Environment & Remediation Research Center, Korea Institute of Science and Technology, Seoul 136-791, Korea, Agrotechnology and Biosciences Division, Malaysian Institute for Nuclear Technology Research (MINT), Bangi, 43000, Kajang, Selangor D.E., Malaysia, and Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea