Recent studies have found that certain urinary proteins can efficiently inhibit stone formation. These discoveries are significant for developing effective therapies for stone disease, but the inhibition mechanism of crystallization remains elusive. In the present study, polyaspartic acid (PASP) was employed as a model peptide to investigate the effect of urinary proteins on the crystallization...

We report a new method for the catalytic, asymmetric synthesis of beta-substituted aspartic acid derivatives in which the nucleophilic catalyst serves up to four discrete roles in a one-pot procedure: catalytic dehydrohalogenation of acid chlorides to form ketenes; catalytic dehydrohalogenation of alpha-chloroamines to form the corresponding imines; catalyzed [2 + 2]-cycloaddition to produce in...

A polypeptide of Mr 4400 was isolated from soybean (Glycine max) seeds by extraction with 60% ethanol followed by ion-exchange and reverse-phase chromatography. The peptide contains an unusually high amount of aspartic acid residues (approximately 25%, and hence is designated as soybean aspartic acid-rich peptide). Its complete primary structure was determined by conventional methods to be the ...

The growth of the eucaryotic microorganism Dictyostelium discoideum in liquid culture was completely inhibited by the aspartic acid analog hadacidin (N-formylhydroxyamino-acetic acid). Growth arrest occurred both in chemically defined medium and in complex growth medium containing aspartic acid and AMP precursors such as adenine and adenosine. Although these compounds could not overcome the eff...

The cell wall compositions of 41 strains of oral filamentous bacteria belonging to the genera Fusobacterium, Leptotrichia and Bacterionema were examined by paper chromatography. Leptotrichia walls showed principally alanine, glutamic acid, DAP, glycine and aspartic acid. The genus Bacterionema had the same amino acids but aspartic acid appeared to be a minor component and was not detected in th...

The occurrence of free D-amino acids and aspartate racemases in several hyperthermophilic archaea was investigated. Aspartic acid in all the hyperthermophilic archaea was highly racemized. The ratio of D-aspartic acid to total aspartic acid was in the range of 43.0 to 49.1%. The crude extracts of the hyperthermophiles exhibited aspartate racemase activity at 70 degrees C, and aspartate racemase...

Studies of the biochemical mechanisms evoked by conventional treatments for neoplastic diseases point to apoptosis as a key process for elimination of unwanted cells. Although the pathways through which chemotherapeutics promote cell death remain largely unknown, caspase proteases play a central role in the induction of apoptosis in response to a variety of stimuli including tumor necrosis fact...

In urea synthesis, according to the Krebs-Henseleit ornithine cycle (l), the transfer of nitrogen to citrulline to form arginine (Step II) was thought to occur from NH$. It was not until Cohen and Hayano (2) succeeded in demonstrating rapid arginine synthesis in liver homogenates from glutamic acid and citrulline that the transfer from an amino acid rather than from NH, was recognized as a main...

The l-amino acid ligase RizA from B. subtilis selectively synthesizes dipeptides containing an N-terminal arginine. Many arginyl have salt-taste enhancing properties while Arg-Phe has been found to antihypertensive effect. A total of 21 variants were created by site-directed mutagenesis eight amino acids in the substrate binding pocket. recombinantly produced E. coli and purified affinity chrom...