L-3- -alanine

L Glutamic acid is not an essential ammo acid It need not be present m the diet because animals can biosynthesize it from sources of a ketoglutaric acid It is however a key intermediate m the biosynthesis of other ammo acids by a process known as transamination L Alanine for example is formed from pyruvic acid by transamination from L glutamic acid... 

Step 3 Hydrolysis of the rearranged mine gives l alanine and a ketoglutarate O2CCH3CH2 COj" "OjCCHjCHj... 

Crystalline Structures. Crystal shape of amino acids varies widely, for example, monoclinic prisms in glycine and orthorhombic needles in L-alanine. X-ray crystallographic analyses of 23 amino acids have been described (31). L-Glutamic acid crystallizes in two polymorphic forms (a and P) (32), and the a-form is mote facdely handled in industrial processes. The crystal stmeture has been determined (33) and is shown in Figure 1. 

L-alanine L-aspartic acid Asp artic- P - decarb oxylase Pseud. dacunhae tQ 192... 

The existence of protein receptors in the tongues of mice and cows have been shown. Monosodium L-glutamate MSG [142-47-2] is utilized as a food flavor enhancer in various seasonings and processed foods. D-Glutamate is tasteless. L-Aspartic acid salt has a weaker taste of umami. Glycine and L-alanine are slightly sweet. The relationship between taste and amino acid stmcture has been discussed (222). 

The ansatrienins ate produced by Streptomjces collinus Tb 1982. The stmctures (Fig. 12) were assigned on the basis of spectral data of the intact antibiotics as well as several derivatives. Acid hydrolysis of the ansatrienins yields L-alanine. The stmctures of ansatrienins A and B ate the same as those for mycotrienins 1 and 11, respectively, except for the configuration of the alanine moiety. The ansatrienins ate active against fungi (45,46). 

L-jS-Pyrazolylalanine (755) and y-L-glutamyl-/8-pyrazol-L-alanine are found in the seeds of many speeies of Cucurbitaceae (65P933). It was subsequently demonstrated that free pyrazole oeeurs in watermelon seeds in eoneentrations of 280 to 410 jLg g depending on the variety (75P2512). Biosynthetic studies implieate 1,3-diaminopropane as a precursor of the pyrazole moiety of (755) (82P863). 

Alanine, ( )- -(2-amino-1,3-selenazol-4-yl)-synthesis, 6, 343 Alanine, phenyl-p-hydroxylation, 7, 565 Alanine, selenienyl-synthesis, 4, 964 Alanine, y3-2-selenienyl-applications, 4, 970 Alanine, y3-3-selenienyl-applications, 4, 970 Alanine, y3-2-thienyl-biological activity, 4, 911 Alanine, -3-thienyl-biological activity, 4, 912 L-Alanine, y-L-glutamyl-y3-pyrazolyl-occurrence, 5, 303 L-Alanine, -pyrazolyl-occurrence, 5, 303 Alanine raeemase inhibition, 1, 266 Albendazole... 

Zwitterionic L-alanine ( HjN—CfCHj)—CO2—) is a dipolar molecule that forms large well-ordered crystals in which the molecules form hydrogen-bonded columns. The strong interactions lead to the presence of well-defined intra- and intermolecular vibrations that can usefully be described using hannonic theory. 

Figure 5 (a) Dispersion curves for crystalline zwitterionic L-alanine at room temperature along... 

These polymers, typical of polyamides with fewer than four main chain carbon atoms in the repeating unit, decompose before melting and have to be processed from solution. Several of the polymers may, however, be spun into fibres. Over thirty years ago Courtaulds produced silk-like fibres on an experimental commercial scale from poly-(L-alanine) and from poly-(a-methyl-L-glutamate). The latter material is also said to be in use as a synthetic leather in Japan. The... 

N-Phthalyl-L-phenylalanine has been prepared by the fusion of L-alanine with phthalic anhydride. 

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