Poly enzymatically synthesized

Ester-thioester copolymers were enzymatically synthesized (Scheme 7). ° The lipase CA-catalyzed copolymerization of e-caprolactone with 11-mercaptoundecanoic acid or 3-mercaptopropionic acid under reduced pressure produced the polymer with molecular weight higher than 2 x 10". The thioester unit of the resulting polymer was lower than the feed ratio. The transesterification between poly(8-caprolactone) and 11-mercaptoundecanoic acid or 3-mercaptopropionic acid also took place by lipase CA catalyst. Recently, aliphatic polythioesters were synthesized by lipase CA-catalyzed polycondensation of diesters with 1,6-hexanedithiol. ... 

Morphology of the enzymatically synthesized phenolic polymers was controlled under the selected reaction conditions. Monodisperse polymer particles in the sub-micron range were produced by HRP-catalyzed dispersion polymerization of phenol in 1,4-dioxane-phosphate buffer (3 2 v/v) using poly(vinyl methyl ether) as stabihzer. °° ° The particle size could be controlled by the stabilizer concentration and solvent composition. Thermal treatment of these particles afforded uniform carbon particles. The particles could be obtained from various phenol monomers such as m-cresol and p-phenylphenol. 

Blends of enzymatically synthesized poly(bisphenol-A) and poly(p-r-butylphenol) with poly(e-CL) were examined. FT-IR analysis showed the expected strong intermolecular hydrogen-bonding interaction between the phenolic polymer with poly(e-CL). A single 7 was observed for the blend, and the value increased as a function of the polymer content, indicating their good miscibility in the amorphous state. In the blend of enzymatically synthesized poly(4,4 -oxybisphenol) with poly(e-CL), both polymers were miscible in the amorphous phase also. The crystallinity of poly(e-CL) decreased by poly(4,4 -oxybisphenol). 

Superoxide anion scavenging activity of the enzymatically synthesized poly(catechin) was evaluated. Poly(catechin), synthesized by HRP catalyst, greatly scavenged superoxide anion in a concentration-dependent manner, and almost completely scavenged at 200 p.M of a catechin unit concentration. The laccase-catalyzed synthesized poly(catechin) also showed excellent antioxidant property. Catechin showed pro-oxidant property in concentrations lower than 300 jlM. These results demonstrated that the enzymatically synthesized poly(catechin) possessed much higher potential for superoxide anion scavenging, compared with intact catechin. 

Xanthine oxidase (XO) is not only an important biological source of ROS but also the enzyme responsible for the formation of uric acid associated with gout leading to painful inflammation in the joints. The XO inhibition effect by the enzymatically synthesized poly(catechin) increased as an increasing concentration of catechin units, while the monomeric catechin showed almost negligible inhibition effect in the same concentration range. ° This markedly amplified XO inhibition activity of poly(catechin) was considered to be due to effective multivalent interaction between XO and the condensed catechin units in the poly (catechin). 

The word "polymer" (first proposed by Berzelius in 1833) is made of "poly" from the ancient Greek word "mlvq" meaning "many" and "pepot " meaning "part". Polymers are molecules built up from numerous identical chemical "units" spatially repeated to form a chain. From the early times and still nowadays, a distinction is often made between "natural" and "synthetic" polymers, but it is somewhat artificial as natural polymers can now sometimes be synthesized (e.g., synthetic "natural rubber") and some synthetic polymers, which are never found in nature, can be synthesized by natural ways (enzymatic syntheses). 

Nagarajan R, Tripathy S, Kumar J, Bruno EE, Samuelson L (2000) An enzymatically synthesized conducting molecular complex of polyanUine and poly(vinyl phosphonic acid). Macromolecules 33(26) 9542-9547... 

Fig. 3 Chemoenzymatic routes to crosslinked macrolactones. Left enzymatic polymerization of a-methylenemacrolides and subsequent vinyl polymerization [10]. Right Enzymatically synthesized highly crystalline poly(ambrettolide) before and after thermal crosslinking [11]...

Enzymatically synthesized polyphenol derivatives are expected to have great potential for electronic applications. The surface resistivity of poly(p-phe-nylphenol) doped with nitrosylhexafluorophosphate was around 105 Q.4a The iodine-labeled poly(catechol) showed low electrical conductivity in the range from 10 6 to 10 9 S/cm.48 The iodine-doped thin film of poly (phenol- co- tetradecyloxyphenol) showed a conductivity of 10 2 S/cm, which was much larger than that obtained in aqueous 1,4-dioxane.24a The third-order optical nonlinearity (%3) of this film was 10 9 esu. An order of magnitude increase in the third-order nonlinear optical properties was observed in comparison with that prepared in the aqueous organic solution. 

Particles of the enzymatically synthesized phenolic polymers were also formed by reverse micellar polymerization. A thiol-containing polymer was synthesized by peroxidase-catalyzed copolymerization of p-hydroxythiophenol and p-ethylphenol in reverse micelles [70], CdS nanoparticles were attached to the copolymer to give polymer-CdS nanocomposites. The reverse micellar system was also effective for the enzymatic synthesis of poly(2-naphthol) consisting of qui-nonoid structure [71], which showed a fluorescence characteristic of the naphthol chromophore. Amphiphilic higher alkyl ester derivatives were enzymatically polymerized in a micellar solution to give surface-active polymers at the air-water interface [72, 73]. 

In the polymerization of catechin by using laccase (ML) as catalyst, the reaction conditions were examined in detail [112], A mixture of acetone and acetate buffer (pH 5) was suitable for the efficient synthesis of soluble poly(catechin) with high molecular weight. The mixed ratio of acetone greatly affected the yield, molecular weight, and solubility of the polymer. The polymer synthesized in 20% acetone showed low solubility toward DMF, whereas the polymer obtained in the acetone content less than 5% was completely soluble in DMF. In the UV-Vis spectrum of poly(catechin) in methanol, a broad peak centered at 370 nm was observed. In alkaline solution, this peak was red-shifted and the peak intensity became larger than that in methanol. In the ESR spectrum of the enzymatically synthesized poly (catechin), a singlet peak at g= 1.982 was detected, whereas the catechin monomer possessed no ESR peak. 

Superoxide anion scavenging activity of the enzymatically synthesized poly(catechin) was evaluated. Poly(catechin), synthesized by HRP catalyst, greatly... 

F.A. Troy, Chemistry and biosynthesis of the poly(-D-glutamyl) capsule in Bacillus licheniformis. n. Characterization and structural properties of the enzymatically synthesized polymer, J. Biol. Chem. 248 (1973)316-324. 

Enzymatic syntheses within the microfluidic platform were also reported. The construction and novel compound synthesis from a synthetic metabolic pathway consisting of a type III poly-ketide synthase (PKS) known as 1,3,6,8-tetrahydroxynaphthalene synthase (THNS) from Streptomyces coelicolor and soybean peroxidase (SBP) in a microreactor were performed (Fig. 5) [11]. THNS immobilized to Ni-NTA agarose... 

This enzymatically synthesized azophenol polymer has an extremely high dye content (nearly 100%) and is soluble in most polar organic solvents. It forms good optical quality thin films. Polymer solutions show reversible trans to cis photoisomerizations of the azobenzene groups with long relaxation time. The poly(azophenol) films also exhibit photoinduced absorption dichroism and large photoinduced birefringence with unusual relaxation behavior. 

R. Nagarajan, S. Tripathy, J. Kumar, F. F. Bruno, L. Samuelson, An enzymatically synthesized conducting molecular complex of polyaniline and poly(vinylphosphonic acid) Macromolecules 2000, 33, 9542. 

A phenol with an acetylenic substituent in the meta position was also chemos-electively polymerized to give the polyphenol having the acetylenic group (274). The resulting polymer was converted to carbonized polymer in a much higher yield than enzymatically synthesized poly(m-cresol). 

Enzymatically synthesized poly(l-hydroxypyrene). 1-Hydroxypyrene was enzymatically oxiized in a mixture of 50% ethanol and 50% buffer (O.OIM phosphate) at pH 6.0 at room temperature as shown in Scheme 3. 

Electronic and photo active polymers such as polyaniline, polyazophenols and poly(l-hydroxypyrene) were synthesized by peroxidase-catalyzed polymerization. These enzymatically synthesized polymers showed interesting electronic and photonic properties. Optical devices such as SRG can be fabricated on the izymatically synthesize polymer thin film. The enzymatic... 

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