[gmt2027]

If the enzyme is produced by genetically altered microbes like bacteria or yeast, wouldn't that make it practically useful on some scale?

[congoe]

Yes, that drives cost down but even on the biggest scale, like insulin, enzymes are still orders of magnitude more expensive than inorganic catalysts (e.g. platinum for hydrogen fuel cells)

[messe]

Not necessarily. Where do they get the energy to produce that enzyme?

Is it more efficient than having them convert sugars to alcohol and burning it?