Microorganisms and their roles in fundamental biogeochemical cycles.

Biogeochemistry is the discipline that strives to understand intricate processes, often microbially mediated ones, that transform and recycle both organic and inorganic substances in soils, sediments, and waters. These processes, manifestations of diverse and highly evolved cellular mechanisms catalyzed by Bacteria and Archaea, maintain the biosphere. Progress in biogeochemistry relies upon the underlying science of environmental microbiology. Over the last 2 years, important discoveries have advanced the ecological, physiological, biochemical, and genomic bases for a variety of microbiological processes including anaerobic methane oxidation, photosynthesis, phosphorous uptake, biodegradation of organic pollutants, and numerous aspects of the nitrogen and sulfur cycles. Here recent literature is assessed and placed within a five-stage paradigm for making scientific progress in environmental microbiology, biogeochemistry, and biotechnology.