The acetylation of p-aminobenzoic acid (PAB) (2) and of sulfanilamide (3) by the rat has been shown to depend upon an adequate supply of pantothenic acid, a constituent of the coenzyme A molecule (4). In addition the extent of acetylation is decreased by giving large amounts of PAB with reference to the size of the animal (5, 6) and to a smaller extent by a deficiency of riboflavin (5). The pre...

The acetylation mechanisms of several selected typical substrates from experiments, including arylamines and arylhydrazines, are investigated with the density functional theory in this paper. The results indicate that all the transition states are characterized by a four-membered ring structure, and hydralazine (HDZ) is the most potent substrate. The bioactivity for all the compounds is increas...

The biological importance of p-aminobenzoic acid was recognized only in 1940 when Woods showed that the compound antagonized the bacteriostatic effects of sulfonamides (2). Later, p-aminobenzoic acid was found to be an essential part of the folic acid molecule (3, 4), and it now seems quite likely that the sole metabolic function of p-aminobenzoate is to serve as a precursor for the biosynthesi...

By means of radioactive iodine it was demonstrated in this laboratory that surviving slices of thyroid tissue can incorporate inorganic iodide into diiodotyrosine and thyroxine (1). When 300 mg. of thyroid slices were incubated for 2 hours in a Ringer’s medium containing radioactive inorganic iodide, as much as 60 per cent of the labeled iodine was organically bound, about 50 per cent as diiodo...

Differences in ionization efficiency among neutral and sialylated glycans prevent direct quantitative comparison by their respective mass spectrometric signals. To overcome this challenge, we developed an integrated chemical strategy, Dual Reactions for Analytical Glycomics (DRAG), to quantitatively compare neutral and sialylated glycans simultaneously by MALDI-MS. Initially, two glycan samples...