Premium
Binding of pyridoxal‐5′‐phosphate and pyridoxamine‐5′‐phosphate: Electrochemical characterization
Author(s) -
Eraso F.,
Pineda T.,
Blazquez M.,
GarciaBlanco F.,
Dominguez M.
Publication year - 1989
Publication title -
journal of physical organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.325
H-Index - 66
eISSN - 1099-1395
pISSN - 0894-3230
DOI - 10.1002/poc.610020603
Subject(s) - chemistry , pyridoxamine , polarography , pyridoxal 5 phosphate , pyridoxal , ionic strength , phosphate , electrochemistry , pyridoxal phosphate , adduct , inorganic chemistry , electrode , organic chemistry , enzyme , cofactor , aqueous solution
Abstract The interaction between pyridoxal‐5′‐phosphate (PLP) and pyridoxamine‐5′‐phosphate (PMP) was studied by d.c. and differential pulse polarography. Two reduction waves (or two peaks) were observed. The first wave corresponds to the reduction of the adduct and the second to the reduction of free PLP. The behaviour was similar in analogous Schiff bases. The effects of pH, PMP concentration and the capillary characteristics were studied. The apparent formation constant as a function of the pH was calculated. Thermodynamic parameters were estimated at pH 7 and 0 · 1 M ionic strength. The polarographic and kinetic results show that the overall electrode process appears to be irreversible in a basic medium.