Synthesis peptide polymerization protein

There are still at least five reaction steps, but only three sequential steps and if each of these proceeds in 90% yield, the overall yield would be (0.90)3 X 100 = 73%. The parallel approach is especially important in the synthesis of polymeric substances such as peptides, proteins, and nucleic acids in which many subunits have to be linked. 

So far, peptide synthesis has mainly involved the preparation of biologically or pharmaceutically relevant substances, total chemical synthesis of natural proteins or protein engineering. The objective of this chapter is to show how the different methods that have been developed for peptide synthesis can be used to prepare biologically-inspired supramolecular architectures and polymeric materials, which might be of potential interest for a variety of advanced applications. 

The physicochemical incompatibility of the polystyrene supports with the peptides has been observed to be one of the problems associated with the original Merrifield method. This has been approached successfully by Sheppard and coworkers by the introduction of the polar polyacrylamide supports. Poly(JV-acrylylpyrrolidine) resin is another polar polymeric support developed on similar grounds. The use of these polar resin supports facilitated the solid phase synthesis of a number of peptides and protein sequences in higher yield and purity than with the polystyrene resins. However, the inadequate availability of these polar supports appears to be a limiting factor for a wider utilization at present. 

The thermal polymers are incapable of mimicing a peptide or protein to the exact extent that the product of a stepwise synthesis does. An exact duplication of a functional protein, however, does little to elucidate the reason for its activity modification and study of the effect on activity are necessary. Systematic synthetic modification of polymeric models is easily achieved in the case of thermal polyamino acids. They are prepared with much ease and in large numbers, and their quantitative compositions can be regulated and controlled simply. Examples are already at hand to illustrate the use of the thermal method to evaluate qualitatively the kinds of amino acid residue that are necessary for, contributory to, or detrimental to, activity. Such studies augment information from enzymes and from nonthermal models. 

Nicolas J, Mantovani G, Haddleton DM (2007) Living radical polymerization as a tool for the synthesis of polymer-protein/peptide bioconjugates. Macromol Rapid Commun 28 1083-1 111... 

Synthesis of Peptide. There is continual progress ia the improvement of instmments and reagents for peptide synthesis, especially "soHd phase polymerization" (90) (see Proteins). This method is suitable for the synthesis of peptides with 20 30 amino acid units. 

Some six hundred structures of naturally occurring carbogenic molecules appe on the pages which follow, together with the name of each compound and references to the original literature of successful chemical synthesis. Thus, Part Three of this book is effectively a key to the literature of chemical synthesis as applied to the complex molecules of nature. The survey does not include oligomeric or polymeric structures, such as peptides, proteins, carbohydrates and polynucleotides, which fall outside the scope of this book because they can be assembled by repetitive procedures. 

Proteins are informational macromolecules, the ultimate heirs of the genetic information encoded in the sequence of nucleotide bases within the chromosomes. Each protein is composed of one or more polypeptide chains, and each peptide chain is a linear polymer of amino acids. The order of the amino acids commonly found in the polypeptide chain is determined by the order of nucleotides in the corresponding messenger RNA template. In this chapter we examine four aspects of protein metabolism (fig. 29.1) (1) The process whereby amino acids are ordered and polymerized into polypeptide chains (2) posttranslational alterations in polypeptides, which occur after they are assembled on the ribosome (3) the targeting process whereby proteins move from their site of synthesis to their sites of function and (4) the proteolytic reactions that result in the return of proteins to their starting material, amino acids. 

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