Cunha Aline G, Fernández-Lorente Gloria, Gutarra Melissa L E, Bevilaqua Juliana V, Almeida Rodrigo V, Paiva Lúcia M C, Fernández-Lafuente Roberto, Guisán Jose M, Freire Denise M G
Instituto de Química, Centro de Tecnologia, Universidade Federal do Rio de Janeiro, lab. 549-1, Ilha do Fundão, CEP 21945-970 Rio de Janeiro, RJ, Brazil.
Appl Biochem Biotechnol. 2009 May;156(1-3):133-45. doi: 10.1007/s12010-008-8425-7. Epub 2008 Nov 28.
Lipases are an enzyme class of a great importance as biocatalysts applied to organic chemistry. However, it is still necessary to search for new enzymes with special characteristics such as good stability towards high temperatures, organic solvents, and high stereoselectivity presence. The present work's aim was to immobilize the lipases pool produced by Penicillium simplissicimum, a filamentous fungi strain isolated from Brazilian babassu cake residue. P. simplissicimum lipases were separated into three different fractions using selective adsorption method on different hydrophobic supports (butyl-, phenyl-, and octyl-agarose) at low ionic strength. After immobilization, it was observed that these fractions' hyperactivation is in the range of 131% to 1133%. This phenomenon probably occurs due to enzyme open form stabilization when immobilized onto hydrophobic supports. Those fractions showed different thermal stability, specificity, and enantioselectivity towards some substrates. Enantiomeric ratio for the hydrolysis of (R,S) 2-O-butyryl-2-phenylacetic acid ranged from 1 to 7.9 for different immobilized P. simplissicimum lipase fractions. Asymmetry factor for diethyl 2-phenylmalonate hydrolysis ranged from 11.8 to 16.4 according to the immobilized P. simplissicimum lipase fractions. Those results showed that sequential adsorption methodology was an efficient strategy to obtain new biocatalysts with different enantioselectivity degrees, thermostability, and specificity prepared with a crude extract produced by a simple and low-cost technology.
脂肪酶作为应用于有机化学的生物催化剂,是一类非常重要的酶。然而,仍有必要寻找具有特殊特性的新酶,如对高温、有机溶剂具有良好的稳定性以及具有高立体选择性。本研究的目的是固定由简单青霉产生的脂肪酶库,简单青霉是从巴西巴巴苏饼残渣中分离出的一种丝状真菌菌株。在低离子强度下,利用选择性吸附法将简单青霉脂肪酶在不同的疏水载体(丁基、苯基和辛基琼脂糖)上分离成三个不同的组分。固定化后,观察到这些组分的超活化率在131%至1133%之间。这种现象可能是由于酶固定在疏水载体上时开放形式的稳定化所致。这些组分对某些底物表现出不同的热稳定性、特异性和对映选择性。不同固定化简单青霉脂肪酶组分对(R,S)2-O-丁酰基-2-苯基乙酸水解的对映体比率在1至7.9之间。根据固定化简单青霉脂肪酶组分,2-苯基丙二酸二乙酯水解的不对称因子在11.8至16.4之间。这些结果表明,顺序吸附方法是一种有效的策略,可通过简单且低成本的技术从粗提物中获得具有不同对映选择性、热稳定性和特异性的新型生物催化剂。