1. Chemoautotrophic origin of life: the Iron-Sulfur World Hypothesis; Günter Wächtershäuser 2. Evolution of metabolic pathways and evolution of genomes; Giovanni Emiliani, Marco Fondi, Pietro Liò, and Renato Fani 3. Novel cultivation strategies for environmentally important microorganisms; Jörg Overmann 4. Environmental proteomics: Studying structure and function of microbial communities; Thomas Schneider and Kathrin Riedel 5. Analysis of microbial communities by functional gene arrays; Jizhong Zhou, Zhili He, and Joy D. Van Nostrand 6. Probing identity and physiology of uncultured microorganisms with isotope labeling techniques; Alexander Loy and Michael Pester 7. The geomicrobiology of arsenic; Rhesa N. Ledbetter and Timothy S. Magnuson 8. Bioinformatics and genomics of iron- and sulfur-oxidizing acidophiles; Violaine Bonnefoy 9. The geomicrobiology of catastrophe: a comparison of microbial colonization in post-volcanic and impact environments; Charles S. Cockell 10. Microbial diversity of cave ecosystems; Annette S. Engel 11. Statistical evaluation of bacterial 16S rRNA gene sequences in relation to travertine mineral precipitation and water chemistry at Mammoth Hot Springs, Yellowstone National Park, USA; Héctor García Martín, John Veysey, George T. Bonheyo, Nigel Goldenfeld and Bruce W. Fouke 12. Compositional, physiological and metabolic variability in microbial communities associated with geochemically diverse, deep-sea hydrothermal vent fluids; Ken Takai and Kentaro Nakamura 13. The molecular geomicrobiology of bacterial manganese(II) oxidation; Bradley M. Tebo, Kati Geszvain and Sung-Woo Lee 14. Role of microorganisms in banded iron formations; Inga Koehler, Kurt Konhauser and Andreas Kappler 15. Synergistic roles of microorganisms in mineral precipitates associated with deep sea methane seeps; Huifang Xu 16. Bacterial degradation of polychlorinated biphenyls; Martina Mackova, Ondrej Uhlik, Petra Lovecka, Jitka Viktorova, MartinaNovakova, Katerina Demnerova, Michel Sylvestre and Tomas Macek 17. Role of clay and organic matter in the biodegradation of organics in soil; Laura E. McAllister and Kirk T. Semple 18. Electrodes as electron acceptors, and the bacteria who love them; Daniel R. Bond 19. The biogeochemistry of biomining; Barrie D. Johnson