RIKEN Center for Sustainable Resource Science 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan, Department of Biotechnology and Life Science, Faculty of Technology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan and Research Center for Environmental Genomics, Kobe University, 1-1 Rokko dai, Nada, Kobe 657-8501, Japan RIKEN Center for Sustainable Resource Science 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan, Department of Biotechnology and Life Science, Faculty of Technology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan and Research Center for Environmental Genomics, Kobe University, 1-1 Rokko dai, Nada, Kobe 657-8501, Japan.