The aim of this course is to impart detailed knowledge about the energy metabolism of anaerobic microorganisms. Here, we will give a broad overview over the vast variety of metabolic pathways these organisms have evolved to solve the problem of energy conservation under nutrient limited conditions found in many natural habitats. The daily two-hour morning sessions include lectures about the biochemistry of anaerobic metabolic pathways as well as methodology lectures in biochemistry and genetics used in microbiology. Theoretical lectures will address, e.g., microbial fermentations, anaerobic respiration and degradation, symbiotic interactions of microorganisms, phototrophic bacteria, the physiology of microorganisms from extreme habitats like hot springs and deep sea vents and practical applications of anaerobic microorganisms. The course also includes literature seminars and presentations of invited guest speakers. During the practical part of the course, groups of two students will work on individual research projects and practically apply methods such as microbial cultivation and physiology, enzyme assays, metabolite analysis through analytical chemistry, protein purification and identification through proteomics and genomics.