Asparatic acid

Aspartic acid decarboxylase cataly2es the decarboxylation of asparatic acid to yield P-alanine (10), a precursor for the biosynthesis of pantothenic acid (67). FiaaHy, (R)-pantothenic acid is obtaiaed by coupling P-alaniae (10) with (R)-pantoate (22) ia the presence of pantothenate synthetase ... 

Evidence based on site-directed mutagenesis studies and Pol I crystal structures show motifs A, B and C to be located near the incoming nucleotide triphosphate and constitute the polymerase active site [33 - 35]. Motif A structurally consists of an antiparallel /i-strand containing primarily hydrophobic residues continuing into a a-helix. The essentia] catalytic asparatic acid (Asp-705 of E. coli Pol I) is located within motif A, and forms the floor of the active site in the Palm . Motif B consists of the a-helix O, and comprises one wall of the active site. Motif B has been demonstrated to be... 

Stereocontrolled total syntheses of penicillanic acid S. S -dioxide and 6-aminopenicillanic add from (5)-asparatic add and (i ,i )-tartaric add, respectively, have been reported (Eq. 4.37).45... 

The FCGR3B gene containes another polymorphism site at amino acid position 266 resulting in a substitution of asparatate to alanine. However, its functional relevance has not been demonstrated (6). 

High concentrations of ammonia could increase the ratio of glutamate/a-ketoglutarate (glutamate dehydrogenase reaction) and increase the level of glutamate in the brain. Ammonia also could increase the ratio of asparatate/oxaloacetate the resulting lower level of oxaloacetate would decrease the availability of all citric acid cycle intermediates. 

The table also summarizes a set of information that may be useful when interpreting product ion spectra, mass differences produced by the loss of a small neutral molecule. These losses are observed for both the b- and y-ion series if that ion contains a particular amino acid. As a result, observation of these losses can be used as a general indicator of amino acid content of the peptide or product ion. The most common loses are water (18Da) and ammonia (17Da). Loss of water typically occurs from the alcohol-(serine and threonine) or carboxylic acid- (asparatate and glutamate) containing anfino... 

Amino acids alanine, asparagine, asparatate, cysteine, glutamate, glutamine, glutathione, histidine, iso-leucine, leucine, lysine, methionine, phenylalanine, sarcosine, serine, tryptophan, tyrosine, valine. 

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