The method of Bruton and Hartley for the isolation of short NH2-terminal sequences of peptides has been applied to /3-galactosidase. Maleyl-P-galactosidase was hydrolyzed with thermolysin and the digest was acidified. After passage through Dowex 50, Thr-Met was obtained from the eluate. This procedure has been extended. For the isolation of a larger NH&erminal peptide, maleyl-protein was treate...

The N-chloroacetyl and N-acetyl derivatives of some thirty racemic amino acids have been employed as starting materials for the subsequent enzymatic separation of the compounds into their opt.ical enantiomorphs (l-3).’ The procedure was always conducted in the absence of added buffer salts, the pH being set at 7 to 8 by addition of alkali to the aqueous solutions of the substrates. At the concl...

In the title compound, C(20)H(22)O(8)S, the dihedral angle between the two benzene rings is 81.6 (3)°. The benzene-connected portions of the alk-oxy substituents are almost coplanar with their respective rings [C-C-O-C torsion angles of 174.77 (17) and -178.5 (4)°]. One of the butanoic acid groups is disordered over two conformations with a site-occupancy ratio 0.719 (6):0.281 (6). In the cryst...

Glycosylated p-hydroxybenzoic acid methyl esters and structurally related phenolphthiocerol glycolipids are important virulence factors of Mycobacterium tuberculosis. Although both types of molecules are thought to be derived from p-hydroxybenzoic acid, the origin of this putative biosynthetic precursor in mycobacteria remained to be established. We describe the characterization of a transposon...

According to the literature, p-aminobenzoic acid (PAB) is excreted in the urine mostly as the free acid and its N-acetyl derivative; the remaining part is eliminated conjugated with glucuronic acid and as p-aminohippuric acid (PAH) (Ellinger & Hensel, 1914'; Hensel, 1914; Cohen & McGilvery, 1946; Salassa, Bollman & Dry, 1948). There is no agreement concerning the formation of PAH. Thus, Beyer, ...