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Alpha-amino acids, polymer

Deming TJ (2000) Living polymerization of alpha-amino acid-N-carboxyanhydrides. J Polym Sci Polym Chem 38 3011-3018... [Pg.23]

The many different monodisperse polymers of amino acids, which are essential components of plants and animals, are called proteins. This word is derived from the Greek porteios meaning of chief importance. The 20 different alpha-amino acids are joined together by peptide linkages (Table 10.1). [Pg.302]

See for example Benoit, H., Freund, L. and Spach, G. in Fasman, G. ed. Poly-alpha-amino acids . Vol. 1, p. 105, Dekker, 1967 and Samulski, E. T. Liquid crystalline order in polypeptides, in A. Blumstein, ed., Liquid Crystalline Order in Polymers . Academic Press, New York, NY 1978... [Pg.54]

Maurer, P. H. Antigenicity of polypeptides (poly-alpha-amino acids). XVII. Immunologic studies in humans with polymers containing L or D and L-alpha-amino acids. J. Immunol. 95 1095-1099, 1965. [Pg.403]

Wool. Wool fibers are comprised mainly of proteins the polypeptide polymers in wool are produced from some 20 alpha-amino acids. The major chemical features of the polypeptide polymer are the amide links, which occur between the amino acids along the polymer chain, and the cystine (sulfur to sulfur) crosslinks, which occur in a random spacing between the polymer chains. The polymer contains many amine, carboxylic acid, and amide groups, which contribute in part to the water-absorbent nature of the fiber. [Pg.504]

Peptide Short, linear polymers of alpha-amino acids formed by covalent bonds... [Pg.254]

Arvanitoyannis, I., Nikolaou, E., and Yamamoto, N., 1994, Novel biodegradable copolyamides based on adipic acid, bis(p-aminocyclohexyl) methane and several alpha-amino acids - Synthesis, characterization and study of their degradability for food packaging applications - 4. Polymer 35 4678-4689. [Pg.280]

Wulff, G. Vietmeier, J. Enzyme-analogue built polymers. 25. Synthesis of macroporous copolymers from alpha.-amino acid-based vinyl compounds. Makromol. Chem. 1989,... [Pg.222]

J. M. Anderson, K. L. Spilizewski, A. Hiltner, Poly-alpha-amino acids as biomedical polymers, in Biocompatibility of Tissue Analogs (CRC Press, Boca Raton, 1985) pp 67-88. [Pg.950]

Kiniwa H, Doi Y, Nishikaji T, Ogata N (1987) Poly(alpha-amino acid)-immobilized polymer adsorbents for optical resolution.3. A total chromatographic optical resolution on poly(N-5-benzyl-L-glutamine)-immobilized resin. Makromol Chem 188 1851-1860... [Pg.412]

Szwarc, M. (1965) The kinetics and mechanism of N-carboxy-alpha-amino-acid anhydride (NCA) polymerization to poiy-amino acids. Advances in Polymer Science, 4,1-65. [Pg.488]

Alpha amino acids are organic acid molecules that also happen to contain an amino group (—NH2) on the second carbon atom of the acid s chain. Proteins are condensation polymers of such alpha amino acids. The reaction by which the long chain of the protein forms is very similar to the reaction by which nylon forms, resulting in the formation of the linkage... [Pg.617]

Armelin E, Paracuellos N, Rodriguez-Galan A, Puiggali J (2001), Study on the degradability of poly(ester amide)s derived from alpha-amino acids glycine, and L-alanine containing a variable amide/ester ratio . Polymer, 42 (19), 7923-7932. [Pg.133]

Proteins are also important nitrogen compounds. They constitute much of the cell materials, and are present in every type of organism known. In humans, muscle tissue, skin, and hair is mostly protein, about half of the dry weight of our bodies. From a chemical point of view, proteins are polymers of amino acids, alpha amine derivatives of carboxylic acids. Only about 20 different amino acids are actually found in proteins. It is the large number of variations in the protein chain, using only these... [Pg.325]

The essential distinction between the approaches used to formulate and evaluate proteins, compared with conventional low molecular weight drugs, lies in the need to maintain several levels of protein structure and the unique chemical and physical properties that these higher-order structures convey. Proteins are condensation polymers of amino acids, joined by peptide bonds. The levels of protein architecture are typically described in terms of the four orders of structure [23,24] depicted in Fig. 2. The primary structure refers to the sequence of amino acids and the location of any disulfide bonds. Secondary structure is derived from the steric relations of amino acid residues that are close to one another. The alpha-helix and beta-pleated sheet are examples of periodic secondary structure. Tertiary... [Pg.697]

The choice of a matrix tailored for a particular kind of polymer sample is cmcial for successful characterization of the sample. Therefore, it is useful to discuss the properties of some common matrices [4—6], 3-Amino-4-hydroxybenzoic acid and POPOP need high laser power, since they possess a high threshold. Alpha-cyanocynnamic acid is... [Pg.300]

Kempe M, Mosbach K. Chiral recognition of N alpha-protected amino acids and derivatives in non-covalently molecularly imprinted polymers. Int J Peptide Protein Res 1994 44 603 -606. [Pg.424]

The life that we know also uses proteins for the majority of structural and catalytic functions. Proteins are particularly suited for these functions because of the structural properties of polymers of amino acids. The polyamide backbone of proteins is neutral, unlike that of nucleic acids. Further, the backbone has a repeating dipole able to make hydrogen bonds. These structural features are exploited as proteins fold into globular structures, as they promote the formation of stable secondary structures such as alpha helices and beta sheets. [Pg.40]

Alternative amino acids are easily conceived, both in theory and from experiment. Many alternative amino acids are known in meteorites (Figure 4.5). Several classes, including alpha-methylamino acids, form secondary structures more easily than do standard terran amino acids. Little is known, however, about the ability of polymers built from them to support catalysis. [Pg.67]

Given the planarity of the amide linkage between amino acids, the distance between all of the alpha-carbons is 3.8 A. A second simplification is to maintain a constant distance of 3.8 A between the alpha-carbons (denoted aC in Figure 5)and to remove the amide (denoted as HN) and carbonyl (denoted as C -O ) functionalities. The combination of these two simplifications reduces the peptide chain to two points per amino acid. It is not a great leap to reduce the polymer chain to one point with a distance of 3.8 A between each point. The problem with this second simplification is the loss of the hydrogen bonding capability... [Pg.647]

Optical isomer separations that are carried out on a chiral layer produced from C-18 modified silica gel impregnated with a Cu(II) salt and an optically active enantiomerically pure hydroxyproline derivative, on a silica layer impregnated with a chiral selector such as brucine,on molecularly imprinted polymers of alpha-agonists,or on cellulose with mobile phases having added chiral selectors such as cyclodextrins have been reported mostly for amino acids and their derivatives. Mixtures of sorbents have been used to prepare layers with special selectivity properties. [Pg.539]

Figure 14.2. The biochemistry of protein. Protein is another linear polymer in which each building block is an amino acid. Amino acids have a central ( alpha ) carbon to which an amino group, a carboxyl group, and a variable side chain are joined. Twenty amino acids are encoded within the standard genetic code. Figure 14.2. The biochemistry of protein. Protein is another linear polymer in which each building block is an amino acid. Amino acids have a central ( alpha ) carbon to which an amino group, a carboxyl group, and a variable side chain are joined. Twenty amino acids are encoded within the standard genetic code.
Proteins are polymers comprised exclnsively of L-amino acids. When the alpha carbon (C ) is viewed from the hydrogen atom, rotation from C=0 (C ) to R to N is clock-... [Pg.109]


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See also in sourсe #XX -- [ Pg.2717 ]




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