This super-extremophile, using genetic instructions from a few different microbes, would create a complex a molecule called Acetyl Coenzyme-A, or Acetyl Co-A for short.

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The fungus uses a common carbohydrate processing enzyme called acetyl co-A to form the building blocks of hydrocarbons--but its unique chemical pathways are not yet understood nor is the process by which the gases escape the fungal membrane into the air.

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From there, it's a relatively easy and well-known process to turn Acetyl Co-A into a fuel like butanol or ethanol.

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