In polypeptides

Shakhnovich E and Gutin A 1989 Formation of unique structure in polypeptide chains. Theoretical... 

Polypeptide Synthesis and Analysis. Sihca or controUed-pore glass supports treated with (chloromethyl)phenylethyltrimethoxysilane [68128-25-6] or its derivatives are replacing chloromethylated styrene—divinylbenzene (Merrifield resin) as supports in polypeptide synthesis. The sdylated support reacts with the triethyl ammonium salt of a protected amino acid. Once the initial amino acid residue has been coupled to the support, a variety of peptide synthesis methods can be used (34). At the completion of synthesis, the anchored peptide is separated from the support with hydrogen bromide in acetic acid (see Protein engineering Proteins). 

Fortunately, it was found that in polypeptide systems the effective dimensionality of conformational spaces is significantly smaller than the dimensionality of the full space, with only a few principal axes contributing to the projection [38-41]. In fact, in many cases a projection quality of 70-90% can be achieved in as few as tliree dimensions [42], opening the way for real 3D visualization of molecular conformational space. Figure 8... 

Figure 11.11 Schematic diagrams of the specificity pockets of chymotrypsin, trypsin and elastase, illustrating the preference for a side chain adjacent to the scisslle bond In polypeptide substrates. Chymotrypsin prefers aromatic side chains and trypsin prefers positively charged side chains that can interact with Asp 189 at the bottom of the specificity pocket. The pocket is blocked in elastase, which therefore prefers small uncharged side chains.

Fig. 7. Scheme of the intermolecular forces stabilizing ordered structures in polypeptides and proteins m... 

As it is the case in polypeptide folding, nonspecific or promiscuous RNA-binding proteins can prevent RNA mis-folding and resolve mis-foldedRNAs, thereby ensuring that RNA is accessible for its biological function [ 1 ]. Certain DEAD-box proteins as well as some proteins that are involved in the assembly of ribonuleoparticles were shown to act as RNA chaperones. 

Cong Y, Yang ZZ (2000) General atom-bond electronegativity equalization method and its application in prediction of charge distributions in polypeptide. Chem Phys Lett 316(3-4) 324-329... 

Although the ROA spectra of typical /1-sheet proteins share some of the features observed in /3-sheet poly-L-lysine, there are also some differences, especially in the amide I region. This is because the /1-sheet in proteins tends to be twisted and irregular, whereas that in polypeptides tends to be extended, multistranded and relatively flat. 

Minakuchi, H., Ishizuka, N., Nakanishi, K., Soga, N., Tanaka, N. (1998a). Performance of an octadecylsilylated continuous porous silica column in polypeptide separation. J. Chromatogr. A 828, 83-90. 

Tanaka, N., Kimata, K., Mikawa, Y., Hosoya, K., Araki, T., Ohtsu, Y., Shiojima, Y., Tsuboi, R., Tsuchiya, H. (1990). Performance of wide-pore silica- and polymer-based packing materials in polypeptide separation the effect of pore size and alkyl chain length. J. Chromatogr. 535, 13-31. 

Fig. 4.9 A synthesis resulting in polypeptides (or compounds similar to polypeptides using amino-malonitrile and further adding hydrogen cyanide. In this process, R 15 may represent different side chains of amino acids...

Suhai, S. 1985. Perturbation Theoretical Calculation of Optical Effects in Polypeptides. J. Mol. Struct. (Theochem) 123, 97-108. 

Lifson, S. Roig, A., Theory of helix-coil transition in polypeptides, J. Chem. Phys. 1961, 34, 1963-1974. 

Goss, D. J., Parkhurst, L. J., Mehta, H. B., Woodley, C. L., and Wahba, A.J. (1984). Studies on the role of eukaryotic nucleotide exchange factor in polypeptide chain initiation. 

The side chains do not participate in polypeptide formation and are thus free to interact and react with their environment. 

Typical examples are the conversion of the neutral form of an amino acid into its zwitterionic form, the helix-coil transitions in polypeptides and polynucleotides, and other conformational changes in biopolymers. Reactions of higher molecularity in which reactants and products have different dipole moments are subject to the same effect (association of the carboxylic acids to form hydrogen-bonded dimers). Equilibrium involving ions are often more sensitive to the application of an electric field ... 

Tomlinson, E., Site-Specific Proteins, in Polypeptide and Protein Drugs Production,... 

The future of LC-MS in polypeptide drug discovery lies in the increasing use of automated online sample clean-up and use of nano LC-MS, both of which greatly increase speed, sensitivity,... 

Local Dynamics in Polypeptides Studied by Solid State 2H NMR Side Chain Dynamics of Poly(Y-benzyl L-glutamate) and Racemic Poly(Y-benzyl glutamate)... 

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