Glutamic Acids and Glutamines

Glutamic Acid and Glutamine was a topic at the same symposium. This chapter s introduction stated that... 

The first example of a dynamic flux analysis was a study performed in the 1960s [269]. In the yeast Candida utilis, the authors determined metabolic fluxes via the amino acid synthesis network by applying a pulse with 15N-labeled ammonia and chasing the label with unlabeled ammonia. Differential equations were then used to calculate the isotope abundance of intermediates in these pathways, with unknown rate values fitted to experimental data. In this way, the authors could show that only glutamic acid and glutamine-amide receive their nitrogen atoms directly from ammonia, to then pass it on to the other amino acids. 

Fluorocitrate is therefore a pseudosubstrate. As well as inhibiting cellular respiration, inhibition of the TCA cycle will also reduce the supply of 2-oxoglutarate. This may decrease the removal of ammonia via formation of glutamic acid and glutamine, and this might account for the convulsions seen in some species after exposure to fluoroacetate. The toxicity is manifested as a malfunction of the CNS and heart, giving rise to nausea, apprehension, convulsions, and defects of cardiac rhythm, leading to ventricular fibrillation. Fluoroacetate and fluorocitrate do not appear to inhibit other enzymes involved in intermediary metabolism, and the di- and trifluoroacetic acids are not similarly incorporated and therefore do not produce the same toxic effects. 

Given the pKa values in the text, predict how the titration curves for glutamic acid and glutamine differ. 

Your liver is also a site for amino acid synthesis such as Serine, Glycine, Glutamic acid and Glutamine. This means that the liver will hang on to some amino acids for bio-synthesis while passing others onto the general circulation for transportation to other organs and tissue. 

Figure 1. Shortened chromatogram of amino acids in air-dried carrots. Peak C represents Amadori compounds formed by reaction between glucose and the amino acids threonine, serine, asparagine, glutamic acid, and glutamine.

Figure 9.40 Chromatograms of o-phthaldialdehyde, glutamic acid, and glutamine standards. Sample contained 5 nmol of glutamic acid and 10 nmol of glutamine. (From Martin et al., 1982.)...

Glutamic acid and Glutamine Proline Glycine Alanine Half-cystine Valine Methionine Isoleucine Leucine Tyrosine Phenylalanine Tryptophan... 

Cyclization of aspartic acid and asparagine to form aspartimides, and to a lesser extent of glutamic acid and glutamine to form glutarimide is an acid- and base-catalyzed common side reaction in peptide synthesis (see also Section 2.2.2). In SPPS it is particularly troublesome when Asp-Gly, Asp-Ala, and Asp-Ser sequences are present,but also with Asp-Asn.P P Piperidine-catalyzed aspartimide formation can be very rapid,and in this context DBU is even worse than piperidine.P The formation of aspartimide is reduced by the addition of HOBt or 2,4-dinitrophenol, but more efficiently it is reduced by protecting the aspartyl amide bond with the 2-hydroxy-4-methoxybenzyl (Hmb) group (see Section 2.3.2).P 1... 

Moroni F., Tanganelli S, Bianchi C., Moneti G, and Beam L (1980) A mass-fragmentographic approach to release studies of endogenous GABA, glutamic acid and glutamine in vitro Pharmacol. Res. Comm 12, 501-505... 

The proposed biosynthesis of piperazate residue of kutznerides, in analogy with monamycin and polyoxypeptin biosynthesis [213, 214], starts from the precursors glutamic acid and glutamine. The N—bond formation is achieved by the initial A-hydroxylation catalyzed by Ktzl, followed by the intramolecular displacement of the hydroxyl group by 5-amine as a nucleophile. The y,5-deidropiperazate is the common intermediate for all four piperazate moieties in kutznerides. Tautomerization of enamine to imine forms the -N unsaturated dehydropiperazate. Reduction of hydrazone leads to piperazate. The biosynthesis of y-chloro-substituted piperazate... 

Lammens TM, Le Notre J, Franssen MC, Scott EL, Sanders JP. (201 la). Synthesis of biobased succinonitrile from glutamic acid and glutamine. ChemSusChem, 4, 785-791. 

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