Amino acids tables

Many kinds of amino acids (eg, L-lysine, L-omithine, t-phenylalanine, L-threonine, L-tyrosine, L-valine) are accumulated by auxotrophic mutant strains (which are altered to require some growth factors such as vitamins and amino acids) (Table 6, Primary mutation) (22). In these mutants, the formation of regulatory effector(s) on the amino acid biosynthesis is genetically blocked and the concentration of the effector(s) is kept low enough to release the regulation and iaduce the overproduction of the corresponding amino acid and its accumulation outside the cells (22). 

Bond Distances, Bond Angles, and Bond Energies in Ethane, Ethene, and Ethyne (Table 9.1, p. 342) Stmctures of a-Amino Acids (Table 27.1, pp. 1054-1055)... 

First, they compared CSPs 1 and 3 prepared by the two-step solid-phase methodology with their commercially available counterparts (CSPs 2 and 4) obtained by direct reaction of the preformed selector with a silica support. Although no exact data characterizing the surface coverage density for these phases were reported, all of the CSPs separated all four racemates tested equally. These results shown in Table 3-3 subsequently led to the preparation of a series of dipeptide and tripeptide CSPs 5-10 using a similar synthetic approach. Although the majority of these phases exhibited selectivities lower or similar to those of selectors built around a single amino acid (Table 3-3), this study demonstrated that the solid-phase synthesis was a... 

Physicochemical Aspects. Other than toxicity toward insects, the protein of the crystals has no unique characteristics not shared by other protein molecules. It contains between 17.5 (15) and 18% (1) nitrogen, present in 17 to 19 amino acids (Table I), none of which are unusual or present in any unusual concentration. The protein is sensitive to heat and when dissolved (0.01N hydroxide) absorbs characteristically at the 280-m/ maximum displayed by aromatic amino acids. 

The AB polyamides are made from either >-amino acids or cyclic lactams, derivatives of the oj-amino acids (Table 3.1). In these polymers, the amino and acid groups are inherently balanced and the polymer also contains one amino and one acid endgroup. There are a number of different routes available for polymerizing these AB-type polyamides ... 

In the rearrangement of divinylaziridines 289, the participation of a boat-like transition state 290 explained the stereochemical outcome of the reactions to give the azepinones 291 in 73 to 85% yield. The divinylaziridines 289 were synthesized via ex-chiral pool sequences starting from optically active a-amino acids. Table 16, Eq. (26) [55]. 

Pseudopoly (amino acids) TABLE 1 Poly (N-acylhydroxyproline esters) 203... 

An aminoaciduria usually results from the congenital absence of an enzyme needed for metabolism of an amino acid. Aminoacidopathies typically involve an inherited deficiency of an enzyme that is important for the metabolism of a particular amino acid (Table 40-1). The concentration of that amino acid and its metabolites consequently rise sharply in blood, urine and body tissues, including the brain. When the enzymatic deficiency is nearly complete, the onset of disease tends to occur in infancy, even in the neonatal period. Partial enzyme deficiencies may not become apparent until later in life [1,2]. 

The basic assembly kit of 20 amino acids (Table 4.1) can be divided notionally into those which have non-polar, uncharged and generally hydrophobic side chains those which have polar, but uncharged side chains and those which have polar, charged side chains. 

Derivatives of amino acids (Table 9.10) are required because amino acids are not themselves sufficiently volatile for gas-liquid chromatography and difficulties may be encountered in the choice and method of derivatization. In the past no single column was normally capable of resolving the derivatives of such a diverse group of compounds but the introduction of fused silica capillary columns has resulted in considerably improved resolution. 

Twenty amino acids are constituents of the peptide chains found in nature. These are generally referred to as the common amino acids (Table 6.1). Less-common amino acids are listed in Table 6.2, including selenocysteine, often called the 21st natural amino acid . Although of little relevance here, we note that the 22nd amino acid , pyrrolysine, was discovered in 2002 in the genetic code of certain Archea and eubacteria [1],... 

In addition to esters of a-amino acids, Table 8.9 also lists four prodrugs of metronidazole where the pro-moieties are longer-chain amino acids, namely... 

Most of the E. coli ribosomal proteins are rather basic with high isoelectric points (Kaltschmidt, 1971) and a high content of basic amino acids (Tables I and II). The complete primary structures of all . coli ribosomal proteins have been determined by Wittmann-Liebold and coworkers (see Table III and Appendix). 

Table 1-17-5 identifies some important products formed from amino acids. Table 1-17-5. Products of Amino Adds...

There are ten transporters so that some transport more than one amino acid (Table 8.8). 

This combination of reactions is known as transdeamination and is the mechanism for deamination of a number of amino acids (Table 8.9). The role of this process in catabolism is shown in Figure 8.10. The ammonia that is prodnced is converted, almost exclnsively, to urea for excretion. Becanse of the biochemical and clinical significance of ammonia, a whole chapter is devoted to it and to urea formation. 

The transport of amino acids into the brain (i.e. across the blood-brain barrier) requires a specific transporter, as for transport of amino acids in other tissues. The transporter that transports tyrosine and tryptophan into the brain also transports the branched-chain amino acids (Table 8.8). Hence, the branched-chain amino acids can compete with... 

Alternatively, cleavage can be done chemically, but here specificity of cleavage at a single defined position is complicated, since most chemical cleavage methods react with single amino acids (Table 5.13). For instance, chemical cleavage at the C-terminal side of methionine residue can be effected using CNBr, but the use of this method is limited, since most proteins are likely to contain internal methionine residues. 

The Silurian Wills Creek, Tonoloway and Keyser Formations were tested for residual amino acids (Table V). The following were found cystine( ), histidine(P), arginine, glycine(P), aspartic acid(P), glutamic acid(P), threonine, alanine, valine, leucine. 

Table 5-5 shows the codon assignments, as we now know them, for each of the 20 amino acids. Table 5-6 shows the same 64 codons in a rectangular array. 

Although this reaction is useful for preparing a-amino acids (Table 22.3, fifth entry), it is not a general method for the synthesis of amines. Its major limitation is that the expected primary amine product is itself a nucleophile and competes with ammonia for the alkyl halide. 

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