Immobilization of Escherichia coli containing ω-transaminase activity in LentiKats®
Immobilization of Escherichia coli containing ω-transaminase activity in LentiKats®
复制标题
DOI：
10.1002/btpr.1538
复制
发表时间：
2012-05-01
影响因子：
2.9
通讯作者：
Woodley, John M.
中科院分区：
文献类型：
--
作者：
Cardenas-Fernandez, Max;Neto, Watson;Woodley, John M.
整个大肠杆菌细胞过表达？转氨酶(?用LentiKats (R)包裹的固定化细胞和-TA作为生物催化剂，催化了芳香手性胺1-苯乙胺（PEA）和3-氨基-1-苯基丁烷（APB）的不对称合成。用不同浓度的西曲溴铵（CTAB）和乙醇使全细胞通透；当CTAB浓度为0.1%时，反应速率比全细胞提高40%，效果最好。以异丙胺（IPA）和l -丙氨酸（Ala）为氨基给体合成了PEA。采用全细胞生物催化，IPA的反应速度比Ala快一个数量级。当渗透性大肠杆菌细胞含有？-TA以Ala为氨基给体。此外，还研究了4-苯基-2-丁酮与异丙酸合成APB的方法。完整细胞和渗透细胞含有？-TA及其固定化LentiKats (R)对应物在反应体系中表现出相似的初始反应速率和产率，表明固定化效率为100%（观察活性/固定化活性），并且没有扩散限制（由于固定化）。全细胞和渗透细胞的固定化LentiKats (R)中的-TA提高了生物催化剂的稳定性，因为该生物催化剂被证明可以有效地重复使用5个反应周期，保留了大约80%的原始活性。(C) 2012美国化学工程师学会。掠夺。, 2012年
Whole Escherichia coli cells overexpressing ?-transaminase (?-TA) and immobilized cells entrapped in LentiKats (R) were used as biocatalysts in the asymmetric synthesis of the aromatic chiral amines 1-phenylethylamine (PEA) and 3-amino-1-phenylbutane (APB). Whole cells were permeabilized with different concentrations of cetrimonium bromide (CTAB) and ethanol; the best results were obtained with CTAB 0.1% which resulted in an increase in reaction rate by 40% compared to the whole cells. The synthesis of PEA was carried out using isopropyl amine (IPA) and L-alanine (Ala) as amino donors. Using whole cell biocatalysis, the reaction with IPA was one order of magnitude faster than with Ala. No reaction was detected when permeabilized E. coli cells containing ?-TA were employed using Ala as the amino donor. Additionally, the synthesis of APB from 4-phenyl-2-butanone and IPA was studied. Whole and permeabilized cells containing ?-TA and their immobilized LentiKats (R) counterparts showed similar initial reactions rates and yields in the reaction systems, indicating 100% of immobilization efficiency (observed activity/activity immobilized) and absence of diffusional limitations (due to the immobilization). Immobilization of whole and permeabilized cells containing ?-TA in LentiKats (R) allowed improved stability as the biocatalyst was shown to be efficiently reused for five reaction cycles, retaining around 80% of original activity. (C) 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012