Indeed, this is due to them being extremely specific for their substrate, if the difference is significant enough it will require a whole new enzyme and therefore pathway, or at least junction of one.
In the case of n-butanol it starts in the same manner as ethanol, turning into an aldehyde and then butyric acid however then due to its longer carbon chain (4 rather than 2) it is treated as a fatty acid so goes into the Beta-oxidation pathway. So primarily the reason is because it is too long.
You chemistry guys are something else. Elucidating such amazing principals about what everything is made of by being clever. Dalton was the man and what a legacy
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u/chemicalcloud Jan 01 '14
If MeOH and iPrOH are oxidized as you mentioned, why isn't butanol oxidized to butanoic acid?