Serine hydroxymethyltransferase. 31P nuclear magnetic resonance study of the enzyme-bound pyridoxal 5'-phosphate.

The environment of the phosphate group of pyridoxal-P bound at the active site of cytosolic serine hydroxymethyltransferase has been investigated by 31P NMR spectroscopy. In the holoenzyme, the pyridoxal-P chemical shift is pH-dependent with a pKa of 6.45.