From Geocycles to Genomes and Back

This chapter discusses the ways a budding geomicrobiologist might embark on the quest to understand how microbial communities affect environment and to predict how they will respond in the face of environmental change. It introduces various methods geomicrobiologists have at their disposal to achieve this goal, including both traditional nonmolecular and molecular methods. It focuses on iron, which is one of the most ubiquitous and biogeochemically relevant metals in the environment. The chapter provides a brief review of the (bio)geochemistry of this element and describes Lake Matano, an iron-rich environment that is geochemically fascinating with respect to metal cycling. It presents the known-facts about Lake Matano and discusses how the traditional and the molecular microbiological approaches described can be used to gain insight into the manner in which microorganisms affect the biogeochemical cycling of iron and other elements in the environment. Once whole genomes of novel organisms from this environment would become available, bioinformatics provides powerful additional tools to search for metabolic key components that contribute to the biogeochemical cycling of iron and other elements in this environment.