Poly-L-glutamic acid

Japanese have also shown interest in poly-(L-glutamic acid) for the manufacture of silk-like fibres. 

Polypeptides form various secondary structures (a-heUx, 3-sheet, etc.), depending on solution pHs. We have investigated end-anchored poly(L-glutamic acid) andpoly(L-lysine) in various secondary structures [11,29,35,36], using the analytical method for the steric force... 

Figure 11a shows a force-distance profile measnred for poly(L-glutamic acid) brushes (2C18PLGA(44)) in water (pH = 3.0, 10 M HNO3) deposited at 40 mN/m from the water subphase at pH = 3.0. The majority of peptides are in the forms of an a-helix (38% determined from the amide I band) and a random coil. Two major regions are clearly seen in... 

Fig. 3. Backscattered Raman (/R + /L) and ROA (/R — /L) spectra of poly-L-lysine in o -helical (top pair) and disordered (second pair) conformations, and of poly-L-glutamic acid in a-helical (third pair) and disordered (bottom pair) conformations in aqueous solution. Reprinted from Barron et al., 2000, Prog. Biophys. Mol. Biol. 73, 1-49, with permission from Elsevier Science.

Positive ROA bands in the range 1297-1312 cm-1 are also characteristic of a-helix. These are observed at 1300 cm-1 in human serum albumin (Fig. 4) and at 1297 cm-1 in a-helical poly-L-lysine (Fig. 3). These additional bands appear to be associated with a-helix in a more hydrophobic environment (Barron etal., 2000). The striking absence of a positive ROA band in the range 1297-1312 cm-1 in a-helical poly-L-glutamic acid would then suggest that only the hydrated form of a-helix is present, possibly due to the shorter side chains relative to poly-L-lysine,... 

More than 36 years ago, the pH-induced cooperative transitions in CD spectra and other physical properties of poly-L-glutamic acid (PGA) and poly-L-lysine (PL) were reported and taken to correspond to a... 

The most common carrier proteins in use today are keyhole limpet hemocyanin (KLH MW 4.5 X 105 to 1.3 X 107), BSA (MW 67,000), aminoethylated (or cationized) BSA (cBSA), thyroglobulin (MW 660,000), ovalbumin (OVA MW 43,000), and various toxoid proteins, including tetanus toxoid and diphtheria toxoid. Other proteins occasionally used include myoglobin, rabbit serum albumin, immunoglobulin molecules (particularly IgG) from bovine or mouse sera, tuberculin purified protein derivative, and synthetic polypeptides such as poly-L-lysine and poly-L-glutamic acid. 

Higashi N, Shosu T, Koga T, Niwa M, Tanigawa T (2006) pH-responsive, self-assembling nanoparticle from a fullerene-tagged poly(L-glutamic acid) and its superoxide dismutase mimetic property. J. Colloid Interface Sci. 298 118-123. 

Figure 8.1. Dependence of initial polymerization rate in the presence ofpoly(methaciylicacid)(l), poly(acrylic acid) (2), poly(l-glutamic acid) (3), at pH=6 and polsrphosphate (4) at pH=5.56 at 20°C tga =2. Reprinted from V. A. Kabanov, O. V. Kargina, and V. A. Petrovskaya, Vysokomol. Soed.,...

Application of classical type of kinetic equations to the template polymerization was demonstrated by Kabanov at al It was shown that 4-vinylpyridine, in the presence of poly(methacrylic acid), poly(acrylic acid), poly(l-glutamic acid), and polyphosphate, polymerizes according to the classical equation and the order of reaction with respect to the monomer is 2 as demonstrated in the Figure 8.1. In log-log coordinates, for the all sets of polymerizations, experimental points fit straight lines. In the same paper dependence of the initial rate on the molar ratio of acid to monomer was examined. This relationship is shown on the Figure 8.2. The rate of polymerization in the presence of the poly(acrylic acid) is much higher than that for the low molecular analogue (acetic acid). The polymerization rate riches its maximum for the molar ratio [acid]/[monomer] 2. The authors found kinetic equation for template polymerization of 4-vinylpyridine in the presence of different polyacids in the form ... 

---