Aspartic acid is prepared chemically or by the fermentation of carbohydrates. Currently, low molecular weight polyaspartic acids are prepared commercially by heating aspartic acid at high temperatures (>220 C) for several hours in the solid state. In an effort to develop a more rapid, continuous, melt polymerization scheme, aspartic acid was copolymerized with adipic, azelaic, sebacic, and dode...

塩屋 明利 ・倉石 弘一 ・柿本 守夫 ・玉真 洋子 In a healthy subject, ammonia produced in the body is excreted by the kidney in the form of urea, the product of the urea cycle (1), or converted into substances useful for the body. In cases of hepatic disorders, on the other hand, blood ammonia level is known to increase (2-6). It is likely that ammonia in high concentrations interferes with the TCA cycle (7) and th...

Aspartes and α-glutamates of the alkali (Li, Na, K) and alkaline earth metals (Mg, Ca) are important components for many preparations in the pharmaceutical industry [1]. L-aspartic and L-α-glutamic acid in particular, which are ubiquitous in nature, have been shown to form a large variety of salts and complexes with these metals both in aqueous solution and in the solid state depending on the p...

Strain is eliminated as a factor in hydrolysis of the scissile peptide bond by human immunodeficiency virus (HIV)-1 and simian immunodeficiency virus (SIV), based on the first eight complexes of products of hydrolysis with the enzymes. The carboxyl group generated at the scissile bond interacts with both catalytic aspartic acids. The structures directly suggest the interactions of the gemdiol i...

In the preceding paper (1) it was found that some strains of S. muscae required the addition of a substance found in certain acid-hydrolyzed proteins (AHPF) to liberate phage in Fildes' synthetic medium when singly infected with virus. Another strain required aspartic acid to liberate phage in Fildes' synthetic medium when singly infected. Experiments reported in this paper show that such strai...

Bone sialoprotein (BSP) is a bone-specific glycoprotein containing phosphoserine and sulphotyrosine residues and regions of contiguous glutamic acid residues. Recent studies in this laboratory have shown that BSP is capable of nucleating the bone mineral hydroxyapatite in a steady-state agarose gel system. We show here that chemical modification of carboxylate groups abolishes the nucleation ac...

The influence of four inhibitors of the high-affinity glutamate uptake system (DL-aspartic acid beta-hydroxymate, DL-AHM; L-aspartic acid beta-hydroxymate, L-AHM; threo-beta-methylaspartate, DLM; L-transpyrrolidine-2, 4-dicarboxylate, PDC) on potentials recorded from hippocampal slices was investigated. At low concentrations of DL-AHM, L-AHM and DLM (50-150 microM) the population spike was perm...