Polyglutamate

Fig. XV-16. A schematic drawing of the arrangement of polyglutamates having alkyl side chains in an LB film. The circles represent the rodlike polyglutamate backbone oriented perpendicular to the page the wiggly lines are the alkyl sidechains. (From Ref. 182.)...

A unique but widely studied polymeric LB system are the polyglutamates or hairy rod polymers. These polymers have a hydrophilic rod of helical polyglutamate with hydrophobic alkyl side chains. Their rigidity and amphiphilic-ity imparts order (lyotropic and thermotropic) in LB films and they take on a F-type stmcture such as that illustrated in Fig. XV-16 [182]. These LB films are useful for waveguides, photoresists, and chemical sensors. LB films of these polymers are very thermally stable, as was indicated by the lack of interdiffusion up to 414 K shown by neutron reflectivity of alternating hydrogenated and deuterated layers [183]. AFM measurements have shown that these films take on different stmctures if directly deposited onto silicon or onto LB films of cadmium arachidate [184]. 

Ralitrexed is a folate analog with greater selectivity. It easily crosses the cell membrane and undergoes polyglutamation. Within tissues, ralitrexed may be stored up to 29 days. It directly inhibits thymidylate synthase, the key enzyme for synthesizing thymidine triphosphate (TTP). The drug has been described to induce apoptosis in tumor cells. Ralitrexed is used for the treatment of colon carcinomas. 

Hanby WE, Waley SG, Watson J (1948) Synthetic polyglutamic acid. Nature 161 132 Hanby WE, Waley SG,Watson J (1950) 632. Synthetic polypeptides. Part n. Polyglutamic acid. J Chem Soc 3239-3249... 

An interesting example of core shielding is represented by Pd porphyrins surrounded by polyglutamic dendrons up to the fourth generation (24-26) [57]. In... 

Bacillus anthracis, the causative organism of anthrax, possesses a capsule composed of polyglutamic acid the slime layers produced by other organisms are of a carbohydrate nature. 

Poly-L-lysine and polyglutamic acid Poly-L-aspartic acid Polypeptide-mustard conjugates HPMA... 

M 0004. (From Tiffany and Krimm, 1969, Biopolymers 8, 347-359, 1969. Reprinted by permission of John Wiley Sons, Inc.) (B) CD spectrum of poly-L-proline II (sigma, molecular weight 55,000) as a function of temperature. (C) CD spectrum of polyglutamic acid at pH 7 as a function of temperature. (D) CD spectrum of poly-L-lysine at pH 7 as a function of temperature. Parts (B-D) are from Tiffany and Krimm (1972). Biopolymers 11, 2309-2316, 1972. Reprinted by permission of John Wiley 8c Sons, Inc. 

Kurosaki T, Kitahara T, Fumoto S, Nishida K, Nakamura J, Niidome T, Kodama Y, Nakagawa H, To H, Sasaki H (2009) Ternary complexes of pDNA, polyethylenimine, and gamma-polyglutamic acid for gene delivery systems. Biomaterials 30 2846-2853... 

Kurosaki T, Kitahara T, Kawakami S, Higuchi Y, Yamaguchi A, Nakagawa H, Kodama Y, Hamamoto T, Hashida M, Sasaki H (2010) Gamma-polyglutamic acid-coated vectors for effective and safe gene therapy. J Control Release 142 404-4-10... 

Polyglutamic Acid Low Induced High Flexible Linear Side Chain Moderate... 

Chitosan/Polyglutamic Acid/ (No Coating) T P/R Chitosan is Cytotoxic... 

Most of the folates that occur naturally in man are polyglutamates,46 although they are transported as monoglutamates. 4 7... 

Because of the multiplicity of folic acid factors reported in whole blood (Ul), the microbiologic assay for folic acid in whole blood and serum was regarded as valueless (C2, L8, W9) results based on S. faecalis methods (C2, C3) did not contradict this view. Streptococcus faecalis is inferior to L. casei in its utilization of the PGA polyglutamates... 

H20, S7). In fact, the ability to utilize PGA polyglutamates may be responsible for the superiority of L. casei over S. faecalis. 

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