“I’m just telling you that we know nothing.” That’s how Rolf Thauer jokingly summed up the lecture he gave Wednesday morning to students in the MBL’s Microbial Diversity course. Thauer, however, knows a lot about microbes. A renowned scientist visiting from the Max Planck Institute for Terrestrial Microbiology in Germany, he is the author of a 1977 paper on energy conservation in bacterial growth that has been cited more than 1,600 times.

Thauer outlined the different strategies used by different species of microbes to break down nutrients into waste products. Microbes get the energy they need to live from a series of steps involved in nutrient breakdown. Scientists can theorize what those steps are for a given species, based on the known inputs (nutrients) and outputs (waste products). However, some strategies that are theoretically impossible may actually be used by certain species to obtain energy from nutrients. Thauer cautioned that theoretical nutrient breakdown strategies, while useful to explore, can be based on inaccurate assumptions and tell us “nothing” until they can be verified through experimentation.

Microbial Diversity is a six-and-a-half week course for graduate and post-doctoral students who wish to expand their repertoire of techniques for working with a broad range of microbial communities.

After Rolf Thauer’s lecture, Microbial Diversity students Harris Wang, Ali Ling, David Williams, and Esther Singer discuss their first step in an afternoon lab exploring the use of fluorescence microscopy in identifying different species of microbes.

After Rolf Thauer’s lecture, Microbial Diversity students Harris Wang, Ali Ling, David Williams, and Esther Singer discuss their first step in an afternoon lab exploring the use of fluorescence microscopy in identifying different species of microbes.