Beneath the kelp beds off the coast of southern California, in an oxygen-free and carbon-monoxide rich environment, an obscure undersea microbe called Methanosarcina acetivorans is thriving, due to its unique metabolism.

While other microbes make methane from carbon monoxide, researchers have shown that this species also produces acetate—commonly known as vinegar—in a unique metabolic process that may shed new light on the evolution of life and lay the foundation for a new source of clean fuel.