Methane-producing archaea, known as methanoarchaea, are strictly anaerobic microbes that grow by making methane gas. To do so, they seemingly “bend the rules” of thermodynamics by using a reversible energy conservation pathway. This seminar will share examples of how the Buan lab uses interdisciplinary approaches to study and manipulate energy metabolism in methanoarchaea to control whether metabolic flux is directed towards biomass synthesis and/or methane production. Recently the Buan lab has engineered methanoarchaea to produce the high-value chemical isoprene as a byproduct in addition to methane. As methane is both a potent greenhouse gas as well as a renewable fuel, understanding methanoarcheal biochemistry and physiology is important for predicting or controlling methane emissions from natural sources, and for potentially using these organisms to supply society’s energy and transportation needs.