31P NMR investigations on free and enzyme bound thiamine pyrophosphate

FEBS Letters

Schellenberger, Alfred²  Flatau, Sabine²  Kleinpeter, Erich¹  Fischer, Gunter² 

[1] Dept of Analytical Chemistry, University of Halle, Weinbergweg, 4020 Halle, GDR;Dept of Biochemistry, University of Halle, Domplatz 1, 4020 Halle GDR

关键词: Thiamine pyrophosphate mechanism;    Pyruvate decar☐ylase;    31P NMR;    PDC;    pyruvate decar☐ylase (EC 4.1.1.1);    TPP;    thiamine pyrophosphate;   

DOI  :  10.1016/0014-5793(88)80465-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Pyruvate decar☐ylase (PDC) contains thiamine pyrophosphate (TPP) and Mg²⁺ as cofactors. ³¹P NMR studies with PDC in the presence of added Mn²⁺ reveal the pyrophosphate moiety of TPP to be a nonaccessible area for the external Mn²⁺ and thus proving the Mg-P-complex (taking part in the binding of the coenzyme to the protein) to be a nonaccessible area for the medium. Glyoxylic acid, acting as an inhibitor of PDC by forming a noncleavable bond with the catalytic center of TPP causes a steric immobilization of the coenzyme indicated by a line broadening of the pyrophosphate moiety.

【 授权许可】

Unknown