L-2-aminoadipic acid

C6H10O3 ethylene glycol monomethacrylate 868-77-9 -12.00 1.2884 2 8171 C6H11N04 L-2-aminoadipic acid 1118-90-7 25.00 1.1410 2... 

Penicillins and cephalosporins contain a P-lactam ring, which is fused with a thiazolidine ring. These types of compounds are synthesized by both prokaryotic and eukaryotic microorganisms, including Streptomyces, Penicillium, Aspergillus, and Cephalosporium species (Luckner, 1990). Important precursors are L-2-aminoadipic acid, L-cysteine, and L-valine. An important intermediate is 6-(L-aminoadipyl)-L-cysteinyl-D-valine (Luckner, 1990). The valine unit with a d-configuration found in one portion of the molecule is labeled when radioactively labeled L-valine is added to the culture. The most important antibiotic of this group, penicillin G (3) from Penicillium spp., is derived from similar precursors. 

Following Scheme 4, L-a-aminosuberic acid can be obtained from iV-tosyI -L-gl utamic acid (5, n=2), upon protection of the a-carboxy and tosylamino groups as an oxazolidone 6, by extension of the side chain with the Amdt-Eistert method via the diazo ketone 7 by one methylene moiety in each cycle to produce in subsequent steps the L-a-aminoadipic acid [(5)-2-aminohexanedioic acid, 8, n = 2], L-a-aminopimelic acid [(5)-2-aminoheptanedioic acid, 8, n = 3] and finally L-a-aminosuberic acid [(5)-2-aminooctanedioic acid, 8, n = 4]J22 Treatment with HBr in AcOH was the method of choice for the acidolytic hydrolysis of the tosyl group. 23 ... 

I. 1-1) starts with the polymerization of L-a-aminoadipic acid, L-cysteine, and L-valine to the linear tripeptide L-a-aminoadipyl-L-cysteinyl-D-valine(ACV-peptide). This reaction is catalyzed by the ACV-synthase (MW about 420 kD) through the following steps (1) the ATP-dependent activation of these amino acids to bind them as thiolesters, (2) the epimerization of L-valine, and hnally (3) the condensation by a thiotemplate mechanism [99]. 

Fig.4. L-iysine. 2-Aminoadipic acid pathway of L-lysine biosynthesis.

A -(t-Butyloxycarbonyl)-L-a-aminoadipic acid 1-t-butyl 6-ethyl ester has been prepared from L-aspartic acid. Hypusine (274), a new amino-acid from bovine brain tissue, has been synthesized by a fairly standard sequence. N -Protected L-2,3-diaminopropanoic acids are prepared from N-protected l-aspartic acid by using a Curtius rearrangement. ... 

Side-chain precursors. The incorporation of isotope from deuterophenylacetyl-valine and from phenylacetic acid-1into benzylpenicilUn by P. chrysogenum showed that added phenylacetic acid and some of its derivatives were direct precursors of the penicillin side-chain (Behrens, 1949 Sebek, 1953 Halliday and Arnstein, 1956). The use of DL-a-amino-adipic acid-2- C and 6- C has indicated that free exogenous a-aminoadipic acid can be incorporated into the side-chain of penicillin N by the Cephalosporium sp. (Abraham et al., 1964). However, the isotope from added L-a-aminoadipic acid-6- C was incorporated into the antibiotic much more efficiently than that from the corresponding D-isomer. 

Weber, P. L. Buck, D. R. Capillary Electrophoresis A Past and Simple Method for the Determination of the Amino Acid Composition of Proteins, /. Chem. Educ. 1994, 71, 609-612. This experiment describes a method for determining the amino acid composition of cyctochrome c and lysozyme. The proteins are hydrolyzed in acid, and an internal standard of a-aminoadipic acid is added. Derivatization with naphthalene-2,3-dicarboxaldehyde gives derivatives that absorb at 420 nm. Separation is by MEKC using a buffer solution of 50 mM SDS in 20 mM sodium borate. 

The L-aminoadipic acid 2 side chain fits into subsite -F 1 in roughly the same way as one side of the GlcNAc + 1 pyranosyl ring. Its carboxylate group does not hydrogen bond to the protein, but rather to the arginyl tail these two long side chains extend into subsite + 2. 

Scheme 4 Synthesis of L-a-Aminosuberic Acid from A-Tosyl-i.-glutamic Acid (n = 2) via L-a-Aminoadipic (n = 3) and L-a-Aminopimelic Acid (n = 4) 22 ...

Fig. 10. Structures of nonribosomally synthesized peptides of bacterial origin (1-6) and fungal origin (7-9). Me, N-methylated peptide boni Orn, ornithine 4-MHA, 4-methyl-3-hydroxyanthranilic acid Aad, aminoadipic acid Aeo, 2-amino-9,10-epoxy-8-oxodecanoic acid D-Hiv, D-hydroxyisovaleric acid Bmt, (4i )-4-[( )-2-butenyl]-4-methyl-L-threonine Abu, a-aminoisobutyric acid Sar, sarcosine. The boxes signify gene products for peptide synthetases composed of modules which activate and process the indicated amino acids...

The elucidation of the mechanism of biosynthesis of penicillin stemmed from the discovery that isotopically labelled cysteine and valine were used in the assembly of penicillin by Penicillium chrysogenum (Amstein and Grant, 1954 Amstein and Clubb, 1957). Cysteine and valine together with a-aminoadipic acid are used by Cephalosporium acremonium to synthesise penicillin N (8.27) and cephalosporin C (8.28). Evidence was accumulated that a tripeptide, h-(f.-a-aminoadipoyl)-L-cysteinyl-D-valine (ACV) was formed as an intermediate. Since this tripeptide is not transported into mycelial cells, it must be synthesised intracellularly and synthesis of penicillin from the isotopically labelled tripeptide was demonstrated using a cell-free system. Clearly, ACV is not produced by a ribosomal synthesis of a protein followed by proteolytic processing. The enzyme involved, ACV synthetase, not only forms the two peptide bonds but also epimerises the valine residue. Thus, incubation of [2-2H]-valine with purified ACV synthetase completely removed deuterium... 

L-a-amino-/3-phenylbutyric acid, a, /3-diaminobutyric acid L-a, jJ-diaminopropionic acid, / -aminopropionic acid d-aminovaleric acid, 2-aminohexenoic acid, 6-diazo-5-oxo-amino-hexanoic acid D-a-aminoadipic acid... 

Indolizidine alkaloids contain the indolizidine nucleus with two different cycles. The structural development of this kind of alkaloid is presented in Figure 2.33. The a is L-lysine, as in the case of piperidine, but the p is different. The p is a-aminoadipic acid 5-semialdehyde. The (p is L-pipecolic acid, which is synthesized in plants from piperideine-6-carboxylic acid. In the case of many other organisms, the obligatory intermedia (q>) is derived from the p. The q> retains one ring structure. The indolizidine nucleus is formed only in the synthesis of the /. The deep structural change occurs when cp is transformed by a chain of reactions the formation of CoA ester (CoAe), the Claisen reaction with acetyl or malonyl CoA (Cra/mCoA) and the ring closure process (by amide or imine) to 1-indolizidinone, which... 

In rat liver, Lys degradation (Fig.l) occurs primarily in the mitochondria. Some features of the degradation pathway appear to be a reversal of the reactions of Lys synthesis (Figs. 4 5). Saccharopine is formed, offering a direct route to 2-aminoadipic-6-semialdehyde, and bypassing the cyclic piperideine and piperidine intermediates. The semialdehyde is also produced by a second pathway, initiated by L-amino acid oxidase. The resulting oxoacid cyclizes spontaneously to A -piperideine 2-carboxylic acid. 

L-PIpecolic acid piperidine-2-carboxylic acid, a nonproteogenic amino acid. It is formed from L-ly-sine, either by a-deamination followed by cyclization and reduction, or as a normal intermediate in the degradation of lysine to a-aminoadipic acid. The 4- and 5-hydroxy derivatives of L-P.a. are found especially in mimosas and palms. 

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