The selectivity by (S)-OMAc is favored at low temperature (4 ☌) and buffer ionic strength (10 mM sodium phosphate). ShIE-Octyl is S-stereoselective in the bioconversion of chiral HPBEt and OMAc, and R-stereoselective in the hydrolysis of naproxen methyl ester in presence of 10 % methanol or acetonitrile. The immobilized biocatalyst is selective for esters with simple alcoholic and complex acid structures, but showing the infrequent ability to hydrolyze esters with heteroatomic or aromatic alcoholic substituents, such as phenylethyl butyrate and 7-aminocephalosporanic acid. The immobilized derivative catalyzes the hydrolysis of the pharmaco-logically relevant esters: naproxen methyl ester, 2-oxyranylmethyl acetate (OMAc), methyl-prostaglandin A2 and ethyl-2-hydroxy-4-phenyl butanoate (HPBEt) (determined by RP-HPLC or HPTLC) with 95-100 % conversion in 6240 min, and tolerates 20 % organic solvents. ShIE-Octyl shows 90 % residual activity after 6 days at 30 ☌, and maintains at least 85 % initial activity in presence of 10 % methanol or acetonitrile. In contrast, immobilization appreciably increases the stability toward temperature and organic solvents. The immobilized esterases are maximally stable at pH 7.0 for p-nitrophenylacetate hydrolysis (determined spec-trophotometrically at 348 nm) during 6 days, although immobilization does not enhance the stability of the soluble enzymes toward pH. ShIE-Octyl, synthesized by this simple method, contains semipurified interfacial esterases, including the isotoxins StI and StII. La Paz, Baja California Sur, México.ĥDepartamento de Biocatálisis, Instituto de Catálisis, Consejo Superior de Investigaciones Científicas (CSIC) Campus Cantoblanco, Código Postal 28049, Madrid, España.Īn immobilized biocatalyst (ShIE-Octyl) was obtained by interfacial adsorption on Octyl-Sepharose CL 4B support of all interfacial esterases from the aqueous extract of the sea anemone Stichodactyla helianthus. Calle 200 y 21, Playa, CP 11600, La Habana, Cuba.ģLaboratorio de Biotecnología, Departamento de Microbiología y Virología, Facultad de Biología, Universidad de La Habana, Cuba.ĤCentro de Investigaciones Biológicas del Noroeste, Consejo Nacional de Ciencia y Tecnología (CONACyT). Calle 25 #455 entre I y J, Vedado, CP 10400, La Habana, Cuba.ĢDepartamento de Síntesis Química, Centro de Química Biomolecular, CQB. Guisán 5ġLaboratorio de Tecnología Enzimática, Centro de Estudio de Proteínas, Facultad de Biología, Universidad de La Habana. Esters biotransformation by immobilized interfacial esterases from the Caribbean Sea anemone Stichodactyla helianthusīiotransformación de ésteres por esterasas interfaciales inmovilizadas a partir de la anémona marina Stichodactyla helianthusĪlberto del Monte-Martínez 1, Jorge González-Bacerio 1, Bessy Cutiño-Avila 1, Ritsie Ruiz 2, Rizette Avila 2, Miguel Ramos-Leal 3, Héctor Nolasco 4, Joaquín Díaz 1, José M.
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