Enzyme-catalyzed ring-opening polymerization

Albertsson A-C, Srivastava RK (2008) Recent developments in enzyme-catalyzed ring-opening polymerization. Adv Drug Deliv Rev 60 1077-1093... 

Loeker EC, Duxbury CJ, Kumar R, Gao W, Gross RA, Howdle SM (2004) Enzyme-catalyzed ring-opening polymerization of e-caprolactone in supercritical carbon dioxide. Macromolecules 37 2450-2453... 

Feng Y, Kniifennann J, Klee D, Hdcker H (1999) Enzyme-catalyzed ring-opening polymerization of 3(S)-isopropylmorpholine-2,5-dione. Macromol Rapid Commun 20 88-90... 

Okumara et al. [10] were the first to attempt the enzyme-catalyzed synthesis of oligoesters from a reaction between dicarboxylic acids and diols. Gutman et al. [11] reported the first study on polyester synthesis by enzyme-catalyzed polymerization of A-B type monomers. Two independent groups in 1993 [12, 13] were first to report enzyme-catalyzed ring-opening polymerization (ROP). Their studies focused on 7- and 6-membered unsubstituted cyclic esters, e-caprolactone (e-CL) and 8-valerolactone (8-VL), respectively. 

Matsumura, S., Beppu, H., Tsukuda, K., and Toshima, K. (1996) Enzyme-catalyzed ring-opening polymerization of (3-propiolactone. Biotechnol. Lett., 18 (9), 1041-1046. 

Srivastava, R.K. (2005) High-molecular-weight poly(l,5-dioxepan-2-one) via enzyme-catalyzed ring-opening polymerization. J. Polym. Sci. Part. A Polym. Chem., 43 (18), 4206-4216. 

Schwab, L.W., Kroon, R., Schouten, A.J., and Loos, K. (2008) Enzyme-catalyzed ring-opening polymerization of unsubstituted (3-lactam. Macromol. Rapid Commun., 29, 794-797. 

Figure 12.2 Enantioselective enzyme-catalyzed ring-opening polymerization of caprolactone from PHB-diol [10].

Albertsson, A.-C. Srivastava, R.K. High molecular weight aliphatic polyesters from enzyme-catalyzed ring-opening polymerization and their use ACS Polymer Preprints, 2006, 7(2), 245. 

FIGURE 3.38 Mechanism of enzyme-catalyzed ring-opening polymerization (ROP). 

FIGURE 3.39 Examples of cyclic monomers for enzyme-catalyzed ring-opening polymerization reactions. 

In order to further verify the involvement of catalytic amino acid residues in enzyme-catalyzed ring-opening polymerization, catalytic amino acids of the catalytic domain of the PHB depolymerase were replaced and evaluated for their polymerization activities. PHB depolymerases have structures that consist of a catalytic domain, a putative linker region, and a substrate binding domain (SBD). Three strictly conserved amino acids, serine, aspartate, and histidine, constitute the catalytic triad at the active center of the catalytic domain. The conserved serine is part of the so-called lipase-box... 

Enzyme-catalyzed ring-opening polymerization should open a new frontier for more types of polyesters, such as structural and elemental variations. Such examples may be the enzyme-catalyzed preparation of thio- and phospho-polyesters. 

Srivastava, R.K. and Albertsson, A.-C. (2007) Micro-block copolymers as a result of transesterfication catalyzing behavior of lipase-CA in sequential ROP. Macromolecules, 40(13), 4464-9. Srivastava, R.K. and Albertsson, A.-C. (2006) Porous scaffolds from high molecular weight polyesters synthesized via enzyme-catalyzed ring-opening polymerization. Biomacromolecules, 7(9), 2531-8. 

R. A., Kaplan, D.L. and Swift, G, (1997) Enzyme catalyzed ring-opening polymerization of (o-pentadecalactone. Macromolecules, 30, 2705-11,... 

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