4-HYDROXY-L-THREONINE, A COMMITTED PRECURSOR OF PYRIDOXOL (VITAMIN-B-6)

Having established in an earlier experiment that, in Escherichia coli, 4-hydroxy-L-threonine [(2S,3S)-2-amino-3,4-dihydroxybutanoic acid] lies on the route from glucose to vitamin B-6, it is now demonstrated that the amino acid serves as a precursor of pyridoxol, since C-13 NMR spectroscopy Shows that the intact C-2,3 bond of [2,3-C-13(2)]-4-hydroxy-L-threonine 2 becomes the C-5,6 bond of pyridoxol 1.