Preparation of cross-linked aggregates of aminoacylase from Aspergillus melleus by using bovine serum albumin as an inert additive
Preparation of cross-linked aggregates of aminoacylase from Aspergillus melleus by using bovine serum albumin as an inert additive
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DOI：
10.1016/j.biortech.2010.03.061
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发表时间：
2010-08-01
影响因子：
11.4
通讯作者：
Tan, Xin
中科院分区：
文献类型：
--
作者：
Dong, Tao;Zhao, Lin;Tan, Xin
在不同戊二醛与酶的比例下，研究了添加牛血清白蛋白（BSA）对黑曲霉（EC 3.5.1.14）氨基酰化酶交联酶聚集体（CLEA）的影响。优化后，每100 mg酶中添加10 mg BSA制备的酶解酶活性回收率为82%（命名为CLEA- e -BSA），而不添加BSA制备的酶解酶活性回收率仅为24%（命名为CLEA- e），这是由于酶解酶胺残基含量低。与游离氨基酰化酶相比，CLEA-E-BSA的催化性能（k(cat)/ k -m）从0.357下降到0.270，而CLEA-E-BSA的热稳定性有了明显提高，在47℃孵育24 h后仍保持52%的剩余活性，而游离酶几乎失活。此外，CLEA-E-BSA失活曲线符合双指数失活模型。对CLEA-E-BSA在n -乙酰- dl -蛋氨酸水解中的可重用性进行了评价。即使重复使用10次，CLEA-E-BSA仍有82.4%的残留活性。(C) 2010 Elsevier Ltd.版权所有。
The effects of bovine serum albumin (BSA) addition on the cross-linked enzyme aggregates (CLEA) of aminoacylase from Aspergillus melleus (EC 3.5.1.14) were conducted at varying glutaraldehyde to enzyme ratio. After optimization, CLEA of aminoacylase prepared with 10 mg BSA per 100 mg enzyme retained 82% activity recovery (named CLEA-E-BSA) whereas CLEA prepared without BSA retained only 24% activity recovery (named CLEA-E) due to the low content of amine residues of aminoacylase. Compared with free aminoacylase, the catalytic performance of CLEA-E-BSA (k(cat)/K-m) decreased from 0.357 to 0.270, while the thermal stability of CLEA-E-BSA has improved considerably, maintaining 52% residual activity after 24 h of incubation at 47 degrees C whereas the free enzyme was almost inactivated. Additionally, the inactive curve of CLEA-E-BSA fitted a two-exponential deactivation model. The reusability of CLEA-E-BSA with respect to N-acetyl-DL-methionine hydrolysis was evaluated. CLEA-E-BSA showed 82.4% residual activity even after 10 cycles of repeated use. (C) 2010 Elsevier Ltd. All rights reserved.