1. Department of Biological Sciences, University of Calgary, Calgary, Alberta, T2N 1N4, Canada
2. Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, PO Box 59, 1790 AB Den Burg, The Netherlands
3. Faculty of Geosciences, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, The Netherlands
4. The Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany
5. Geological Survey of Canada, Natural Resources Canada, Calgary, AB T2L 2A7, Canada