Biotransformation of R-2-hydroxy-4-phenylbutyric acid by D-lactate dehydrogenase and Candida boidinii cells containing formate dehydrogenase coimmobilized in a fibrous bed bioreactor
Biotransformation of R-2-hydroxy-4-phenylbutyric acid by D-lactate dehydrogenase and Candida boidinii cells containing formate dehydrogenase coimmobilized in a fibrous bed bioreactor
复制标题
DOI：
10.1002/bit.20582
复制
发表时间：
2005-10-20
影响因子：
3.8
通讯作者：
Yang, ST
中科院分区：
文献类型：
--
作者：
Bai, YL;Yang, ST
r -2-羟基-4-苯基丁酸（R-HPBA）是制造血管紧张素转换酶抑制剂的重要中间体。本研究利用重组d -乳酸脱氢酶（LDH）将2-氧-4-苯基丁酸（OPBA）转化为R-HPBA，同时将β -烟酰胺腺嘌呤clinucleotide （NADH）氧化为NAD（+）。用甲苯预处理假丝酵母细胞使其具有渗透性，利用假丝酵母细胞中存在的甲酸脱氢酶（FDH）再生辅助因子NADH。与分离的FDH相比，整个细胞更稳定，更容易制备。动力学研究表明，反应速率与辅因子NAD（+）的浓度有关，R-HPBA和OPBA均能抑制该反应。以聚乙烯亚胺（PEI）为原料，建立了全细胞与LDH酶在棉布上共固定的新方法，该方法诱导PEI-酶-细胞聚集体的形成及其在棉布上的吸附，从而实现了细胞与酶的多层共固定，具有高负载（0.5 g细胞和8 mg LDH / g棉布）和活性产率（> 95%）。实验结果表明，当OPBA和R-HPBA浓度均小于10 g/L时，反应器产率为9 g/L中心点h，产率为0.95 mol/mol OPBA。(c) 2005 Wiley期刊有限公司
R-2-hydroxy-4-phenylbutyric acid (R-HPBA) is an important intermediate in the manufacture of angiotensin converting enzyme inhibitors. In this work, a recombinant D-lactate dehydrogenase (LDH) was used to transform 2-oxo-4-phenylbutyric acid (OPBA) to R-HPBA, with concomitant oxidation of beta-nicotinamide adenine clinucleotide (NADH) to NAD(+). The cofactor NADH was regenerated by formate dehydrogenase (FDH) present in whole cells of Candida boidinii, which were pre-treated with toluene to make them permeable. The whole cells used in the process were more stable and easier to prepare as compared with the isolated FDH from the cells. Kinetic study showed that the reaction rate was dependent on the concentration of cofactor, NAD(+), and that both R-HPBA and OPBA inhibited the reaction. A novel method for co-immobilization of whole cells and LDH enzyme on cotton cloth was developed using polyethyleneimine (PEI), which induced the formation of PEI-enzyme-cell aggregates and their adsorption onto cotton cloth, leading to multilayer co-immobilization of cells and enzyme with high loading (0.5 g cell and 8 mg LDH per gram of cotton cloth) and activity yield (> 95%). A fibrous bed bioreactor with co-immobilized cells and enzyme on the cotton cloth was then evaluated for R-HPBA production in fed-batch and repeated batch modes, which gave relatively stable reactor productivity of 9 g/L center dot h and product yield of 0.95 mol/mol OPBA when the concentrations of OPBA and R-HPBA were less than 10 g/L. (c) 2005 Wiley Periodicals, Inc.