|MadSci Network: Biochemistry|
Thanks for the questions. This is an interesting problem. Take a look at the metabolic map on this web page:
What this shows you is that metabolically, pathways to and from methanol are rather limited. Basically it can be produced biologically in 2 ways; through the oxidation of methane by methane monooxygenase, or by the reduction of formaldehyde, by methanol dehydrogenase (and this reaction normally works in the reverse direction).
It's true that some methanol can be produced during fermentation, but this is not derived from the ethanol or by carbohydrate oxidation. It is produced in small amounts, either by non-enzymatic reactions or through the reduction of formaldehyde.
Furthermore, in a mixed culture of microorganisms you would probably find a number of methylotrophs-these are microbes that can actually oxidise methanol to gain energy, using methanol dehydrogenase. So it may be possible to use methanotrophic organisms to produce methanol from methane, but a lot of it would probably be consumed again. From this, you can probably see why most methanol production from biomass begins with biological conversion to methane and then continues as an inorganic chemistry process. Have a look at:
for some description of the process.
Having said that, there is always room for more microbiological research. At present, methane from natural gas or from methanogenic organisms is plentiful enough that the chemical production of methanol through gasification is economical. But in the future, biological routes will become more attractive. You might want to consider genetically modified microorganisms with altered biochemical pathways (eg the ability to produce methanol by fermentation). Another route for consideration might be a mixed culture of methanogens (to produce the methane) and organisms that synthesised methane monooxygenase (to oxidise it to methanol), but with no further metabolism.
I hope this answers your questions and gives a few ideas,
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