Ashizawa K, Kato H, McPhie P, Cheng S
Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
Biochem Biophys Res Commun. 1990 Mar 16;167(2):587-92. doi: 10.1016/0006-291x(90)92065-8.
The human cytosolic thyroid hormone binding protein (p58) was recently shown to be a monomer of pyruvate kinase, subtype PKM2, and have intrinsic pyruvate kinase activity. The present study evaluated the effect of L-alpha-alanine on the binding of 3,3',5-triiodo-L-thyronine (T3) and enzymatic activity of p58. Analysis of the competitive binding data indicated that alanine, at the physiological concentration, is a non-competitive inhibitor of T3 binding to p58. Furthermore, alanine was found to be a "mixed" inhibitor of the substrate phosphoenol pyruvate. However, binding of alanine to p58 did not block the association of p58 to form the tetrameric pyruvate kinase.
