Polypeptides poly

Figures 13.54 thru 13.56 have been singled for special mention because of the unusual nature of the applications presented. Because peptides are also polyamides and because we routinely run polyamides using hexafluoro-2-pro-panol (FIFIP) as solvent, a modified polypeptide, poly (leucine-comethyl glutamate), was run in FIFIP. Figure 13.54 shows the results and suggests that modified HFIP might well prove to be a good solvent for at least some polypeptide purifications/characterizations. Figure 13.55 demonstrates the use of modi-...

Shimokuri T, Kaneko T, Serizawa T et al (2004) Preparation and thermosensitivity of naturally occurring polypeptide poly(y-glutamic acid) derivatives modified by alkyl groups. Macromol Biosci 4 407-411... 

Capillary columns packed with polysulfoethyl A (prepared by chemical bonding of a polypeptide, poly (2-sulfoethyl aspartamide), to silica particles)... 

The behavior of rodlike polymers in poor solvents has received comparatively little attention. However, the phase boundaries of the rodlike polypeptide poly-Y benzyl-a, L-glutamate in dimethylformamide (PBLG/DMF) have been determined over a temperature range spanning both poor and good solvent limits.(5,6) As expected from the Flory... 

The synthetic polypeptides poly-L-alanine (—NH. CH(CH3). CO—)p (a form) and poly-y-methyl-L-glutamate... 

In fact, for random-coil conformations, b in Equation 41 is explicitly related to the exponent in the Mark-Houwink equation by 3b = a 1. In this way values of M may be determined directly from measurements of D° provided KD and b are known. Although both these parameters could in principle be calculated from a detailed knowledge of the geometry of the solute, it is usual to regard them as experimentally determinable parameters. A similar relationship has also been found to hold true for the polypeptide poly(y-benzyl L-glutamate) (PBLG) dissolved both in 1,2-dichloroethane and in dichloroacetic acid. These results are shown in Figures 6 and 7, respectively. 

X-ray diffraction played a major role in the discovery of the structure of fibrous proteins. In most cases the fibers under study are oriented in two dimensions by stretching. In this analysis we illustrate how the technique is used to study the a form of the synthetic polypeptide poly-L-alanine. 

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. 

Niven, R.W., F. Rypacek, and P.R. Byron. 1990. Solute absorption from the airways ofthe isolated rat lung. III. Absorption of several peptidase-resistant, synthetic polypeptides poly-(2-hydroxyethyl) -as-partamides. Pharm. Res. 7 990-994. Hoover, J.L., B.D. Rush, K.F. Wilkinson, J.S. Day, P.S. Burton,T.J. Vidmar, and M.J. Ruwart. 1992. Peptides are better absorbed from the lung than the gut in the rat. Pharm. Res. 9 1103-1106. 

The artificial polypeptide poly-L-glutamate forms a helices in solution at pH 2, but not at pH 7. Suggest an explanation. 

The polypeptide poly-L-proline is an interesting and special case because of the exclusively imino peptide linkages of the polymer. The properties of this macromolecule and its high and low molecular weight analogs are discussed in the review of Harrington and von Hippel (1961), and will only briefly be mentioned here. The polymer can exist in two forms of markedly different optical rotatory properties, and can be converted from one form... 

Branched-ehain polypeptides poly[Lys-(Z -DL-Alaj )], where X = Glu, Set, or Boc-Cys(Npys)Opfp, were produeed in our laboratory as deseribed. 

Synthesis of Chloroacetylated-Branched Polypeptide poly[Lys(ClAcfSerrDL-Alam)] (SAK(CIAc)- )... 

Fig. 2. Graphical treatment of dispersion data in Fig. 1 according to the simple Drude equation (11). The disordered forms of the synthetic polypeptides, poly-y-benzyl-L-glutamate (PBG, O — O) and poly-n-glutamio acid (PGA, A — A), give linear plots, which specify their dispersions as simple. The dispersions of bovine serum albumin (BSA) in both its native ( ---- ) and denatured ( — ) forms are...

Menard, L. Synthese de polypeptides poly(amide-urethane-uree)s a utilisation biologique , These Doctorat de I Univer-site du Maine, Le Mans, 1996... 

Classic examples of synthetic polymers exhibiting an aqueous LCST include poly-diethyl acrylamide), poly(dimethylaminoethyl methacrylate), poly(A -acryloylpyrrolidine), poly(2-isopropyl-2-oxazoline), elastin-like artificial polypeptides, poly(vinyl methyl ether) and poly(7V-isopropylacrylamide) (PNIPAM, Scheme 1). The latter has been by far the most studied and applied thermoresponsive polymer and therefore can be considered as the gold standard in this field of research. During the last decades, several thousands of research articles and patents described the synthesis, the properties and the applications of this fascinating macromolecule. 

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