1. S. N. Dedysh, Institute of Microbiology, Russian Academy of Sciences, Moscow 117811, Russia, and Center for Microbial Ecology, Michigan State University, East Lansing, MI 48824–1325, USA. N. S. Panikov, Institute of Microbiology, Russian Academy of Sciences, Moscow 117811, Russia. W. Liesack and R. Großkopf, Max-Planck-Institut für Terrestrische Mikrobiologie, D-35043 Marburg, Germany. J. Zhou and J. M. Tiedje, Center for Microbial Ecology, Michigan State University, East Lansing, MI 48824–1325, USA.