Naturalproductman’s Blog

Hey, is that a natural product?!

Alcohol to carboxylic acid by an enzyme

Posted by naturalproductman on May 7, 2014

Marco Fraaije and co-workers from the University of Groningen in the Netherlands have reported in ACIE on an enzyme catalyzed oxidation of an alcohol to carboxylic acid.


They did a mechanistic study, which caught my attention. They wanted to test if the carboxylic acid arises from the gem-diol of the aldehyde intermediate or directly from the aldehyde. The experiment was run under 18O-labeled water with 4-nitrobenzaldehyde. They state that if the reaction is spontaneous then the aldehyde will directly give the carboxylic acid with no 18O incorporated in the product, but if it is from the gem-diol, you will have 18O-atoms.

I have a problem with this part because the reaction can still come from the aldehyde if the carboxylic acid had an 18O-atom. The way this would occur is that the aldehyde can get hydrated to the gem-diol then it would be in equilibrium with the aldehyde and give back the aldehyde but this time it has an 18O-atom (STEP 2 product of below). This aldehyde, if oxidized by the enzyme, would yield the carboxylic acid with 18O-atom.

Anyway, interesting paper.
ACIE paper

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: