In the reaction, a carbanion at C-2 of TPP is first produced. This carbanion attacks the carbonyl carbon of the alpha -ketose to give an addition product. This image was produced from the PDB file 1TKA.pdb writen by S.Koenig, A. Schellenberger, H. Neef, and G. Schneider. It is evident from the neurological disorders caused by thiamine deficiency that this vitamin plays a vital role in nerve function. It is unclear, however, just what that role is.
Thiamine is found in both the nerves and brain.
The concentration of thiamine in the brain seems to be resistant to changes dietary concentration. This observation suggest that thiamine has a role in the nervous system independent of its coenzyme roles. I believe those, whom this same disease attacks, with their knees shaking and legs raised up, walk like sheep. Unfortunately beri-beri is still common in parts of southeast Asia where polished rice is a staple and thiamine enrichment programs are not fully in place. Dry beri-beri usually inflicts older adults and affects mainly the peripheral nerves with little cardiac involvement.