Polymer amino acid

Amino acid polymers like poly(y-methyl-L-glutamate) [29967-97-3] h.a.ve been developed as raw materials for artificial leathers (see Leatherlike materials). Derivatives of amino acids are now finding new appHcations in industry and agriculture. 

Formation of N-Carboxy-(X-Amino AeidAnhydride (NCA) (85), NCAs are important as starting materials for amino acid polymers. They are prepared by the reaction of amino acids with phosgene in an aptotic solvent. 

Polypeptides (or more simply peptides) are amino acid polymers comprising up to approximately 50 units. 

Proteins and peptides are amino acid polymers in which the individual amino acids, called residues, are linked together by amide bonds, or peptide bonds. An amino group from one residue forms an amide bond with the carboxyl of a second residue, the amino group of the second forms an amide bond with the carboxyl of a third, and so on. For example, alanylserine is the dipeptide that... 

Peptide (Section 26.4) A short amino acid polymer in which the individual amino acid residues are linked by amide bonds. 

Recombinant DNA technology can also be used to design genes that encode for proteins with desired features [34]. The gene can be incorporated into a plasmid, which is then used to transform a bacterial host such as Escherichia coli. Finally, the production of the desired amino acid polymer is performed by the host with a precisely defined sequence and near absolute monodispersity [29, 35]. 

Long amino acid polymers or polypeptides constitute the basic structural unit of proteins, and the structure of a protein provides insight into how it fulfills its functions. 

Polymers of amino acids, like polymers of nucleic acids, have both ionic and hydrophobic character. Unlike the polymers of nucleic acids, amino acid polymers may carry either a negative or a positive (or zero) net charge, are far more subject to irreversible denaturation and oxidation, and are labile to... 

Biochemical tests are usually performed after pure cultures have been obtained. The standard indole, methyl red, Voges-Proskauer, citrate, and litmus milk tests may be used to show important physiological characteristics. To study the functional diversity of bacteria, the utilization of carbohydrates, amines, amides, carboxylic acids, amino acids, polymers, and other carbon and nitrogen sources can be tested.28 Dilution-based most-probable number (MPN) techniques with phospholipid fatty acids as biomarkers have been employed for studying different bacterial species in lakes.40 The patterns of antibiotic resistance in bacteria isolated from natural waters have been useful for identifying sources of water pollution.34... 

Stereosequences in polymers having the general formula — CHR—X—Y— [e.g., poly-a-amino acids, polymers derived from substituted oxiranes, thi-iranes, aziridines, lactones or lactams, and 1,4 polymers of 1- (or 4) monosub-stituted butadienes] are not affected by the degeneracy phenomena existing in vinyl polymers. Their number is indicated in the first column of Table 2. 

J.T. Davies, Some factors influencing the orientation of e-amino groups in monolayers of proteins and amino acid polymers, Biochem. J. 56 (1954) 509-513. 

The protein amino acids are the basic building blocks for all peptide chains (amino acid polymers and oligomers) and protein chains (a protein is a large polypeptide), which make up the structure of an enormous number of biological molecules including enzymes. The chains are held together by peptide links (amide... 

Poly-L-lysine (PLL) An amino acid polymer with many positively charged amino groups. Its cytotoxicity can be mitigated by shielding (56)... 

As mentioned in Chapter 1, Section 1.3.5, organic cations (tensides, amino acids, polymers, etc.) can be used to increase the size of the interlayer space (Fudala et al. 1999). In the increased interlayer space of metallic and metal oxides, nanolayers can be produced by cation exchange and heat treatment (Mogyorosi et al. 2003 Nemeth et al. 2003 Papp and Dekany 2002). The process is frequently carried out in organic media. 

A number of polymers of significant practical importance are polyamides. The most common group in this class is probably that of nylons. These compounds have a numbering system indicating how many carbon atoms are in the monomeric unit. The nylons designated by a single number are amino acid polymers with the structure [-NH-R-C(0)-]n, while those designated by two numbers are formed from a diamine and a dibasic acid and have the structure [-NH-R-NH-C(0)-R -C(0)-]n. 

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