Highly efficient and stereoselective biosynthesis of (2S,5S)-hexanediol with a dehydrogenase from Saccharomyces cerevisiae
Highly efficient and stereoselective biosynthesis of (2S,5S)-hexanediol with a dehydrogenase from Saccharomyces cerevisiae
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DOI：
10.1039/b920869k
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发表时间：
2010-01-01
影响因子：
3.2
通讯作者：
Hummel, Werner
中科院分区：
文献类型：
--
作者：
Mueller, Marion;Katzberg, Michael;Hummel, Werner
对映体纯的（2S，5S）-己二醇作为一种通用的结构单元用于生产各种精细化学品和药物。对于工业和商业规模，目前通过面包师酵母介导的2，5-己二酮还原获得二醇。然而，该方法的缺点是约4g L-1 d（-1）（2S，5S）-己二醇的时空产率不足。因此，需要允许更高体积生产率的新合成路线。出于这个原因，在纯化至均一性和随后的MALDI-TOF质谱分析后，鉴定了负责面包酵母中2，5-己二酮还原的酶。结果，与缺乏对2，5-己二酮的活性的Gre 2 p缺失菌株相比，脱氢酶Gre 2 p显示负责大部分二酮还原。利用重组酶进行生物还原，（2S，5S）-己二醇的转化率>99%，de和ee>99.9%，并且以70 g L-1 d（-1）（2S，5S）-己二醇的高体积生产率获得二醇。Michaelis-Menten动力学研究表明，Gre 2 p能够催化2，5-己二酮的还原以及（2S，5S）-己二醇的氧化，但还原的催化效率高三倍。此外，研究了酶还原其他酮化合物（包括进一步的二酮）的能力，揭示了该应用可以扩展到α-二酮和醛。
The enantiopure (2S,5S)-hexanediol serves as a versatile building block for the production of various fine chemicals and pharmaceuticals. For industrial and commercial scale, the diol is currently obtained through bakers' yeast-mediated reduction of 2,5-hexanedione. However, this process suffers from its insufficient space-time yield of about 4 g L-1 d(-1) (2S, 5S)-hexanediol. Thus, a new synthesis route is required that allows for higher volumetric productivity. For this reason, the enzyme which is responsible for 2,5-hexanedione reduction in bakers' yeast was identified after purification to homogeneity and subsequent MALDI-TOF mass spectroscopy analysis. As a result, the dehydrogenase Gre2p was shown to be responsible for the majority of the diketone reduction, by comparison to a Gre2p deletion strain lacking activity towards 2,5-hexanedione. Bioreduction using the recombinant enzyme afforded the (2S,5S)-hexanediol with >99% conversion yield and in >99.9% de and ee. Moreover, the diol was obtained with an unsurpassed high volumetric productivity of 70 g L-1 d(-1) (2S,5S)-hexanediol. Michaelis-Menten kinetic studies have shown that Gre2p is capable of catalysing both the reduction of 2,5-hexanedione as well as the oxidation of (2S,5S)-hexanediol, but the catalytic efficiency of the reduction is three times higher. Furthermore, the enzyme's ability to reduce other keto-compounds, including further diketones, was studied, revealing that the application can be extended to alpha-diketones and aldehydes.