In:
FEBS Letters, Wiley, Vol. 299, No. 2 ( 1992-03-09), p. 163-165
Abstract:
Decarboxylation of pyruvate by pyruvate decarboxylase (EC 4.1.1.1) was performed in a reaction mixture containing 50% deuterium. The isolated product, acetaldehyde, was investigated directly by 1 H NMR and by mass spectrometry after conversion to the 2,4‐dinitrophenyl hydrazone. The protium content of 56% at acetaldehyde Cl demonstrate a specific protonation of the corresponding intermediate by the enzyme. Proton inventory studies and enzyme modification indicate the 4′ amino group of the coenzyme, thiamine pyrophosphate, in an immonium structure being a possible proton donor. A ‘partially concerted’ mechanism is suggested for the reaction steps following the decarboxylation.
Type of Medium:
Online Resource
ISSN:
0014-5793
,
1873-3468
DOI:
10.1016/0014-5793(92)80238-C
Language:
English
Publisher:
Wiley
Publication Date:
1992
detail.hit.zdb_id:
1460391-3
SSG:
12
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