Phosphoenolpyruvate and Mg2+ binding to pyruvate kinase monitored by infrared spectroscopy.

ABSTRACT: Structural changes in rabbit muscle pyruvate kinase (PK) induced by phosphoenolpyruvate (PEP) and Mg(2+) binding were studied by attenuated total reflection Fourier transform infrared spectroscopy in combination with a dialysis accessory. The experiments indicated a largely preserved secondary structure upon PEP and Mg(2+) binding but also revealed small backbone conformational changes of PK involving all types of secondary structure. To assess the effect of the protein environment on the bound PEP, we assigned and evaluated the infrared absorption bands of bound PEP. These were identified using 2,3-(13)C(2)-labeled PEP. We obtained the following assignments: 1589 cm(-1) (antisymmetric carboxylate stretching vibration); 1415 cm(-1) (symmetric carboxylate stretching vibration); 1214 cm(-1)

SUBMITTER: Kumar S 

PROVIDER: S-EPMC2862152 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature